Major Graphic Engine revision. Now most of the math functions are broken

due to their outdated rendering methods.

.classpath

@@ -3,6 +3,7 @@
 	<classpathentry excluding="org/warp/picalculator/deprecatedmath/" kind="src" path="src"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
 	<classpathentry kind="src" path="res"/>
+	<classpathentry exported="true" kind="con" path="org.eclipse.jdt.USER_LIBRARY/JOGL"/>
 	<classpathentry kind="lib" path="libs/pi4j-1.1/pi4j-core.jar" sourcepath="libs/pi4j-1.1/pi4j-core-sources.jar">
 		<attributes>
 			<attribute name="javadoc_location" value="jar:platform:/resource/PICalculator/libs/pi4j-1.1/pi4j-core-javadoc.jar!/"/>
@@ -28,6 +29,5 @@
 			<attribute name="javadoc_location" value="jar:platform:/resource/PICalculator/libs/objenesis-2.4/objenesis-2.4-javadoc.jar!/"/>
 		</attributes>
 	</classpathentry>
-	<classpathentry kind="con" path="org.eclipse.jdt.USER_LIBRARY/JOGL"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>

.settings/org.eclipse.jdt.core.prefs

@@ -1,12 +1,2 @@
 eclipse.preferences.version=1
-org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
+org.eclipse.jdt.core.javaFormatter=org.eclipse.jdt.core.defaultJavaFormatter
-org.eclipse.jdt.core.compiler.codegen.methodParameters=do not generate
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.8
-org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
-org.eclipse.jdt.core.compiler.compliance=1.8
-org.eclipse.jdt.core.compiler.debug.lineNumber=generate
-org.eclipse.jdt.core.compiler.debug.localVariable=generate
-org.eclipse.jdt.core.compiler.debug.sourceFile=generate
-org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
-org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
-org.eclipse.jdt.core.compiler.source=1.8

.settings/org.eclipse.jdt.ui.prefs

@@ -0,0 +1,60 @@
+cleanup.add_default_serial_version_id=false
+cleanup.add_generated_serial_version_id=true
+cleanup.add_missing_annotations=true
+cleanup.add_missing_deprecated_annotations=true
+cleanup.add_missing_methods=true
+cleanup.add_missing_nls_tags=false
+cleanup.add_missing_override_annotations=true
+cleanup.add_missing_override_annotations_interface_methods=true
+cleanup.add_serial_version_id=true
+cleanup.always_use_blocks=true
+cleanup.always_use_parentheses_in_expressions=true
+cleanup.always_use_this_for_non_static_field_access=false
+cleanup.always_use_this_for_non_static_method_access=false
+cleanup.convert_functional_interfaces=true
+cleanup.convert_to_enhanced_for_loop=true
+cleanup.correct_indentation=true
+cleanup.format_source_code=true
+cleanup.format_source_code_changes_only=false
+cleanup.insert_inferred_type_arguments=false
+cleanup.make_local_variable_final=true
+cleanup.make_parameters_final=false
+cleanup.make_private_fields_final=true
+cleanup.make_type_abstract_if_missing_method=false
+cleanup.make_variable_declarations_final=true
+cleanup.never_use_blocks=false
+cleanup.never_use_parentheses_in_expressions=false
+cleanup.organize_imports=false
+cleanup.qualify_static_field_accesses_with_declaring_class=false
+cleanup.qualify_static_member_accesses_through_instances_with_declaring_class=true
+cleanup.qualify_static_member_accesses_through_subtypes_with_declaring_class=true
+cleanup.qualify_static_member_accesses_with_declaring_class=true
+cleanup.qualify_static_method_accesses_with_declaring_class=false
+cleanup.remove_private_constructors=true
+cleanup.remove_redundant_type_arguments=true
+cleanup.remove_trailing_whitespaces=false
+cleanup.remove_trailing_whitespaces_all=true
+cleanup.remove_trailing_whitespaces_ignore_empty=false
+cleanup.remove_unnecessary_casts=true
+cleanup.remove_unnecessary_nls_tags=true
+cleanup.remove_unused_imports=true
+cleanup.remove_unused_local_variables=false
+cleanup.remove_unused_private_fields=true
+cleanup.remove_unused_private_members=false
+cleanup.remove_unused_private_methods=true
+cleanup.remove_unused_private_types=true
+cleanup.sort_members=false
+cleanup.sort_members_all=false
+cleanup.use_anonymous_class_creation=false
+cleanup.use_blocks=true
+cleanup.use_blocks_only_for_return_and_throw=false
+cleanup.use_lambda=true
+cleanup.use_parentheses_in_expressions=false
+cleanup.use_this_for_non_static_field_access=true
+cleanup.use_this_for_non_static_field_access_only_if_necessary=true
+cleanup.use_this_for_non_static_method_access=true
+cleanup.use_this_for_non_static_method_access_only_if_necessary=true
+cleanup_profile=_Drake's Cleanup
+cleanup_settings_version=2
+eclipse.preferences.version=1
+formatter_settings_version=12

src/com/rits/cloning/Cloner.java

@@ -64,7 +64,7 @@ public class Cloner {
 	private boolean cloneSynthetics = true;
 
 	public Cloner() {
-		this.instantiationStrategy = ObjenesisInstantiationStrategy.getInstance();
+		instantiationStrategy = ObjenesisInstantiationStrategy.getInstance();
 		init();
 	}
 
@@ -113,12 +113,12 @@ public class Cloner {
 		fastCloners.put(ConcurrentHashMap.class, new FastClonerConcurrentHashMap());
 	}
 
-	private IDeepCloner deepCloner = new IDeepCloner() {
+	private final IDeepCloner deepCloner = new IDeepCloner() {
 		@Override
 		public <T> T deepClone(T o, Map<Object, Object> clones) {
 			try {
 				return cloneInternal(o, clones);
-			} catch (IllegalAccessException e) {
+			} catch (final IllegalAccessException e) {
 				// just rethrow unchecked
 				throw new IllegalStateException(e);
 			}
@@ -128,8 +128,9 @@ public class Cloner {
 	protected Object fastClone(final Object o, final Map<Object, Object> clones) throws IllegalAccessException {
 		final Class<? extends Object> c = o.getClass();
 		final IFastCloner fastCloner = fastCloners.get(c);
-		if (fastCloner != null)
+		if (fastCloner != null) {
 			return fastCloner.clone(o, deepCloner, clones);
+		}
 		return null;
 	}
 
@@ -281,8 +282,9 @@ public class Cloner {
 	}
 
 	public void registerFastCloner(final Class<?> c, final IFastCloner fastCloner) {
-		if (fastCloners.containsKey(c))
+		if (fastCloners.containsKey(c)) {
 			throw new IllegalArgumentException(c + " already fast-cloned!");
+		}
 		fastCloners.put(c, fastCloner);
 	}
 
@@ -307,8 +309,9 @@ public class Cloner {
 	public <T> T fastCloneOrNewInstance(final Class<T> c) {
 		try {
 			final T fastClone = (T) fastClone(c, null);
-			if (fastClone != null)
+			if (fastClone != null) {
 				return fastClone;
+			}
 		} catch (final IllegalAccessException e) {
 			throw new RuntimeException(e);
 		}
@@ -326,10 +329,12 @@ public class Cloner {
 	 * @return a deep-clone of "o".
 	 */
 	public <T> T deepClone(final T o) {
-		if (o == null)
+		if (o == null) {
 			return null;
-		if (!cloningEnabled)
+		}
+		if (!cloningEnabled) {
 			return o;
+		}
 		if (dumpCloned != null) {
 			dumpCloned.startCloning(o.getClass());
 		}
@@ -342,10 +347,12 @@ public class Cloner {
 	}
 
 	public <T> T deepCloneDontCloneInstances(final T o, final Object... dontCloneThese) {
-		if (o == null)
+		if (o == null) {
 			return null;
-		if (!cloningEnabled)
+		}
+		if (!cloningEnabled) {
 			return o;
+		}
 		if (dumpCloned != null) {
 			dumpCloned.startCloning(o.getClass());
 		}
@@ -371,10 +378,12 @@ public class Cloner {
 	 * @return a shallow clone of "o"
 	 */
 	public <T> T shallowClone(final T o) {
-		if (o == null)
+		if (o == null) {
 			return null;
-		if (!cloningEnabled)
+		}
+		if (!cloningEnabled) {
 			return o;
+		}
 		try {
 			return cloneInternal(o, null);
 		} catch (final IllegalAccessException e) {
@@ -411,10 +420,12 @@ public class Cloner {
 	 */
 	private boolean isImmutable(final Class<?> clz) {
 		final Boolean isIm = immutables.get(clz);
-		if (isIm != null)
+		if (isIm != null) {
 			return isIm;
-		if (considerImmutable(clz))
+		}
+		if (considerImmutable(clz)) {
 			return true;
+		}
 
 		final Class<?> immutableAnnotation = getImmutableAnnotation();
 		for (final Annotation annotation : clz.getDeclaredAnnotations()) {
@@ -442,34 +453,45 @@ public class Cloner {
 
 	@SuppressWarnings("unchecked")
 	protected <T> T cloneInternal(final T o, final Map<Object, Object> clones) throws IllegalAccessException {
-		if (o == null)
+		if (o == null) {
 			return null;
+		}
 		if (o == this)
+		 {
 			return null; // don't clone the cloner!
-		if (ignoredInstances.containsKey(o))
+		}
+		if (ignoredInstances.containsKey(o)) {
 			return o;
-		if (o instanceof Enum)
+		}
+		if (o instanceof Enum) {
 			return o;
+		}
 		final Class<T> clz = (Class<T>) o.getClass();
 		// skip cloning ignored classes
-		if (nullInstead.contains(clz))
+		if (nullInstead.contains(clz)) {
 			return null;
-		if (ignored.contains(clz))
-			return o;
-		for (final Class<?> iClz : ignoredInstanceOf) {
-			if (iClz.isAssignableFrom(clz))
-				return o;
 		}
-		if (isImmutable(clz))
+		if (ignored.contains(clz)) {
 			return o;
+		}
+		for (final Class<?> iClz : ignoredInstanceOf) {
+			if (iClz.isAssignableFrom(clz)) {
+				return o;
+			}
+		}
+		if (isImmutable(clz)) {
+			return o;
+		}
 		if (o instanceof IFreezable) {
 			final IFreezable f = (IFreezable) o;
-			if (f.isFrozen())
+			if (f.isFrozen()) {
 				return o;
+			}
 		}
 		final Object clonedPreviously = clones != null ? clones.get(o) : null;
-		if (clonedPreviously != null)
+		if (clonedPreviously != null) {
 			return (T) clonedPreviously;
+		}
 
 		final Object fastClone = fastClone(o, clones);
 		if (fastClone != null) {
@@ -549,15 +571,18 @@ public class Cloner {
 	 *            fields of src
 	 */
 	public <T, E extends T> void copyPropertiesOfInheritedClass(final T src, final E dest) {
-		if (src == null)
+		if (src == null) {
 			throw new IllegalArgumentException("src can't be null");
-		if (dest == null)
+		}
+		if (dest == null) {
 			throw new IllegalArgumentException("dest can't be null");
+		}
 		final Class<? extends Object> srcClz = src.getClass();
 		final Class<? extends Object> destClz = dest.getClass();
 		if (srcClz.isArray()) {
-			if (!destClz.isArray())
+			if (!destClz.isArray()) {
 				throw new IllegalArgumentException("can't copy from array to non-array class " + destClz);
+			}
 			final int length = Array.getLength(src);
 			for (int i = 0; i < length; i++) {
 				final Object v = Array.get(src, i);
@@ -639,8 +664,9 @@ public class Cloner {
 					System.out.println("cloned field>" + field + "  -- of class " + clz);
 				}
 			};
-		} else
+		} else {
 			dumpCloned = null;
+		}
 	}
 
 	public boolean isCloningEnabled() {

src/com/rits/cloning/FastClonerCalendar.java

@@ -14,7 +14,7 @@ public class FastClonerCalendar implements IFastCloner {
 	@Override
 	public Object clone(final Object t, final IDeepCloner cloner, final Map<Object, Object> clones) {
 		final GregorianCalendar gc = new GregorianCalendar();
-		Calendar c = (Calendar) t;
+		final Calendar c = (Calendar) t;
 		gc.setTimeInMillis(c.getTimeInMillis());
 		gc.setTimeZone((TimeZone) c.getTimeZone().clone());
 		return gc;

src/com/rits/perspectives/Perspectives.java

@@ -43,10 +43,12 @@ public class Perspectives {
 	 * @return the E perspective of o
 	 */
 	public <T, E extends T> E viewAs(final Class<E> c, final T o) {
-		if (o == null)
+		if (o == null) {
 			return null;
-		if (o instanceof Collection<?>)
+		}
+		if (o instanceof Collection<?>) {
 			throw new IllegalArgumentException("for collections please use viewCollectionAs() method. Invalid object " + o);
+		}
 		final E newInstance = cloner.fastCloneOrNewInstance(c);
 		cloner.copyPropertiesOfInheritedClass(o, newInstance);
 		return newInstance;
@@ -81,8 +83,9 @@ public class Perspectives {
 	 */
 	public <I, NI extends I, T extends Collection<I>, E extends Collection<NI>> E viewCollectionAs(
 			final E newCollection, final Class<NI> perspectiveCollectionItemClass, final T currentCollection) {
-		if (currentCollection == null)
+		if (currentCollection == null) {
 			return null;
+		}
 		for (final I item : currentCollection) {
 			final NI newItem = viewAs(perspectiveCollectionItemClass, item);
 			newCollection.add(newItem);

src/org/nevec/rjm/Bernoulli.java

@@ -35,11 +35,12 @@ public class Bernoulli {
 	 */
 	protected void set(final int n, final Rational value) {
 		final int nindx = n / 2;
-		if (nindx < a.size())
+		if (nindx < a.size()) {
 			a.set(nindx, value);
-		else {
+		} else {
-			while (a.size() < nindx)
+			while (a.size() < nindx) {
 				a.add(Rational.ZERO);
+			}
 			a.add(value);
 		}
 	}
@@ -53,15 +54,16 @@ public class Bernoulli {
 	 * @throws Error
 	 */
 	public Rational at(int n) throws Error {
-		if (n == 1)
+		if (n == 1) {
 			return (new Rational(-1, 2));
-		else if (n % 2 != 0)
+		} else if (n % 2 != 0) {
 			return Rational.ZERO;
-		else {
+		} else {
 			final int nindx = n / 2;
 			if (a.size() <= nindx) {
-				for (int i = 2 * a.size(); i <= n; i += 2)
+				for (int i = 2 * a.size(); i <= n; i += 2) {
 					set(i, doubleSum(i));
+				}
 			}
 			return a.elementAt(nindx);
 		}
@@ -80,11 +82,12 @@ public class Bernoulli {
 			Rational jsum = Rational.ZERO;
 			BigInteger bin = BigInteger.ONE;
 			for (int j = 0; j <= k; j++) {
-				BigInteger jpown = (new BigInteger("" + j)).pow(n);
+				final BigInteger jpown = (new BigInteger("" + j)).pow(n);
-				if (j % 2 == 0)
+				if (j % 2 == 0) {
 					jsum = jsum.add(bin.multiply(jpown));
-				else
+				} else {
 					jsum = jsum.subtract(bin.multiply(jpown));
+				}
 
 				/*
 				 * update binomial(k,j) recursively

src/org/nevec/rjm/BigComplex.java

@@ -165,14 +165,16 @@ public class BigComplex {
 		 * and v= +- sqrt((l-re)/2 as the new real and imaginary parts.
 		 */
 		final BigDecimal l = abs(mc);
-		if (l.compareTo(BigDecimal.ZERO) == 0)
+		if (l.compareTo(BigDecimal.ZERO) == 0) {
 			return new BigComplex(BigDecimalMath.scalePrec(BigDecimal.ZERO, mc), BigDecimalMath.scalePrec(BigDecimal.ZERO, mc));
+		}
 		final BigDecimal u = BigDecimalMath.sqrt(l.add(re).divide(half, mc), mc);
 		final BigDecimal v = BigDecimalMath.sqrt(l.subtract(re).divide(half, mc), mc);
-		if (im.compareTo(BigDecimal.ZERO) >= 0)
+		if (im.compareTo(BigDecimal.ZERO) >= 0) {
 			return new BigComplex(u, v);
-		else
+		} else {
 			return new BigComplex(u, v.negate());
+		}
 	}
 
 	/**

src/org/nevec/rjm/BigIntegerMath.java

@@ -23,14 +23,17 @@ public class BigIntegerMath {
 	 * @return The binomial coefficient
 	 */
 	static public BigInteger binomial(final int n, final int k) {
-		if (k == 0)
+		if (k == 0) {
 			return (BigInteger.ONE);
+		}
 		BigInteger bin = new BigInteger("" + n);
-		BigInteger n2 = bin;
+		final BigInteger n2 = bin;
-		for (BigInteger i = new BigInteger("" + (k - 1)); i.compareTo(BigInteger.ONE) >= 0; i = i.subtract(BigInteger.ONE))
+		for (BigInteger i = new BigInteger("" + (k - 1)); i.compareTo(BigInteger.ONE) >= 0; i = i.subtract(BigInteger.ONE)) {
 			bin = bin.multiply(n2.subtract(i));
-		for (BigInteger i = new BigInteger("" + k); i.compareTo(BigInteger.ONE) == 1; i = i.subtract(BigInteger.ONE))
+		}
+		for (BigInteger i = new BigInteger("" + k); i.compareTo(BigInteger.ONE) == 1; i = i.subtract(BigInteger.ONE)) {
 			bin = bin.divide(i);
+		}
 		return (bin);
 	} /* binomial */
 
@@ -48,8 +51,9 @@ public class BigIntegerMath {
 		/*
 		 * binomial(n,0) =1
 		 */
-		if (k.compareTo(BigInteger.ZERO) == 0)
+		if (k.compareTo(BigInteger.ZERO) == 0) {
 			return (BigInteger.ONE);
+		}
 
 		BigInteger bin = new BigInteger("" + n);
 
@@ -78,8 +82,9 @@ public class BigIntegerMath {
 		 * and in the integer domain. First replace C(n,k) by C(n,n-k) if n-k<k.
 		 */
 		BigInteger truek = new BigInteger(k.toString());
-		if (n.subtract(k).compareTo(k) < 0)
+		if (n.subtract(k).compareTo(k) < 0) {
 			truek = n.subtract(k);
+		}
 
 		/*
 		 * Calculate C(num,truek) where num=n and truek is the smaller of n-k
@@ -168,8 +173,9 @@ public class BigIntegerMath {
 	 * @author Richard J. Mathar
 	 */
 	static public int isqrt(final int n) {
-		if (n < 0)
+		if (n < 0) {
 			throw new ArithmeticException("Negative argument " + n);
+		}
 		final double resul = Math.sqrt(n);
 		return (int) Math.round(resul);
 	}
@@ -185,8 +191,9 @@ public class BigIntegerMath {
 	 * @author Richard J. Mathar
 	 */
 	static public long isqrt(final long n) {
-		if (n < 0)
+		if (n < 0) {
 			throw new ArithmeticException("Negative argument " + n);
+		}
 		final double resul = Math.sqrt(n);
 		return Math.round(resul);
 	}
@@ -202,16 +209,17 @@ public class BigIntegerMath {
 	 * @author Richard J. Mathar
 	 */
 	static public BigInteger isqrt(final BigInteger n) {
-		if (n.compareTo(BigInteger.ZERO) < 0)
+		if (n.compareTo(BigInteger.ZERO) < 0) {
 			throw new ArithmeticException("Negative argument " + n.toString());
+		}
 		/*
 		 * Start with an estimate from a floating point reduction.
 		 */
 		BigInteger x;
 		final int bl = n.bitLength();
-		if (bl > 120)
+		if (bl > 120) {
 			x = n.shiftRight(bl / 2 - 1);
-		else {
+		} else {
 			final double resul = Math.sqrt(n.doubleValue());
 			x = new BigInteger("" + Math.round(resul));
 		}
@@ -221,13 +229,15 @@ public class BigIntegerMath {
 			/*
 			 * check whether the result is accurate, x^2 =n
 			 */
-			BigInteger x2 = x.pow(2);
+			final BigInteger x2 = x.pow(2);
 			BigInteger xplus2 = x.add(BigInteger.ONE).pow(2);
-			if (x2.compareTo(n) <= 0 && xplus2.compareTo(n) > 0)
+			if (x2.compareTo(n) <= 0 && xplus2.compareTo(n) > 0) {
 				return x;
+			}
 			xplus2 = xplus2.subtract(x.shiftLeft(2));
-			if (xplus2.compareTo(n) <= 0 && x2.compareTo(n) > 0)
+			if (xplus2.compareTo(n) <= 0 && x2.compareTo(n) > 0) {
 				return x.subtract(BigInteger.ONE);
+			}
 			/*
 			 * Newton algorithm. This correction is on the
 			 * low side caused by the integer divisions. So the value required
@@ -251,8 +261,9 @@ public class BigIntegerMath {
 	 * @author Richard J. Mathar
 	 */
 	static public BigInteger core(final BigInteger n) {
-		if (n.compareTo(BigInteger.ZERO) < 0)
+		if (n.compareTo(BigInteger.ZERO) < 0) {
 			throw new ArithmeticException("Negative argument " + n);
+		}
 		final Ifactor i = new Ifactor(n);
 		return i.core();
 	}
@@ -278,17 +289,21 @@ public class BigIntegerMath {
 	static public BigInteger[][] minor(final BigInteger[][] A, final int r, final int c) throws ArithmeticException {
 		/* original row count */
 		final int rL = A.length;
-		if (rL == 0)
+		if (rL == 0) {
 			throw new ArithmeticException("zero row count in matrix");
-		if (r < 0 || r >= rL)
+		}
+		if (r < 0 || r >= rL) {
 			throw new ArithmeticException("row number " + r + " out of range 0.." + (rL - 1));
+		}
 		/* original column count */
 		final int cL = A[0].length;
-		if (cL == 0)
+		if (cL == 0) {
 			throw new ArithmeticException("zero column count in matrix");
-		if (c < 0 || c >= cL)
+		}
+		if (c < 0 || c >= cL) {
 			throw new ArithmeticException("column number " + c + " out of range 0.." + (cL - 1));
-		BigInteger M[][] = new BigInteger[rL - 1][cL - 1];
+		}
+		final BigInteger M[][] = new BigInteger[rL - 1][cL - 1];
 		int imrow = 0;
 		for (int row = 0; row < rL; row++) {
 			if (row != r) {
@@ -327,15 +342,18 @@ public class BigIntegerMath {
 			throws ArithmeticException {
 		/* original row count */
 		final int rL = A.length;
-		if (rL == 0)
+		if (rL == 0) {
 			throw new ArithmeticException("zero row count in matrix");
+		}
 		/* original column count */
 		final int cL = A[0].length;
-		if (cL == 0)
+		if (cL == 0) {
 			throw new ArithmeticException("zero column count in matrix");
-		if (c < 0 || c >= cL)
+		}
+		if (c < 0 || c >= cL) {
 			throw new ArithmeticException("column number " + c + " out of range 0.." + (cL - 1));
-		BigInteger M[][] = new BigInteger[rL][cL];
+		}
+		final BigInteger M[][] = new BigInteger[rL][cL];
 		for (int row = 0; row < rL; row++) {
 			for (int col = 0; col < cL; col++) {
 				/*
@@ -343,10 +361,11 @@ public class BigIntegerMath {
 				 * surplus
 				 * elements will be ignored. Shorter v lead to an exception.
 				 */
-				if (col != c)
+				if (col != c) {
 					M[row][col] = A[row][col];
-				else
+				} else {
 					M[row][col] = v[row];
+				}
 			}
 		}
 		return M;
@@ -367,20 +386,21 @@ public class BigIntegerMath {
 		BigInteger d = BigInteger.ZERO;
 		/* row size */
 		final int rL = A.length;
-		if (rL == 0)
+		if (rL == 0) {
 			throw new ArithmeticException("zero row count in matrix");
+		}
 		/* column size */
 		final int cL = A[0].length;
-		if (cL != rL)
+		if (cL != rL) {
 			throw new ArithmeticException("Non-square matrix dim " + rL + " by " + cL);
+		}
 
 		/*
 		 * Compute the low-order cases directly.
 		 */
-		if (rL == 1)
+		if (rL == 1) {
 			return A[0][0];
-
+		} else if (rL == 2) {
-		else if (rL == 2) {
 			d = A[0][0].multiply(A[1][1]);
 			return d.subtract(A[0][1].multiply(A[1][0]));
 		} else {
@@ -393,10 +413,11 @@ public class BigIntegerMath {
 					final BigInteger M[][] = minor(A, r, 0);
 					final BigInteger m = A[r][0].multiply(det(M));
 					/* recursive call */
-					if (r % 2 == 0)
+					if (r % 2 == 0) {
 						d = d.add(m);
-					else
+					} else {
 						d = d.subtract(m);
+					}
 				}
 			}
 		}
@@ -421,26 +442,30 @@ public class BigIntegerMath {
 	static public Rational[] solve(final BigInteger[][] A, final BigInteger[] rhs) throws ArithmeticException, Error {
 
 		final int rL = A.length;
-		if (rL == 0)
+		if (rL == 0) {
 			throw new ArithmeticException("zero row count in matrix");
+		}
 
 		/* column size */
 		final int cL = A[0].length;
-		if (cL != rL)
+		if (cL != rL) {
 			throw new ArithmeticException("Non-square matrix dim " + rL + " by " + cL);
-		if (rhs.length != rL)
+		}
+		if (rhs.length != rL) {
 			throw new ArithmeticException("Right hand side dim " + rhs.length + " unequal matrix dim " + rL);
+		}
 
 		/*
 		 * Gauss elimination
 		 */
-		Rational x[] = new Rational[rL];
+		final Rational x[] = new Rational[rL];
 
 		/*
 		 * copy of r.h.s ito a mutable Rationalright hand side
 		 */
-		for (int c = 0; c < cL; c++)
+		for (int c = 0; c < cL; c++) {
 			x[c] = new Rational(rhs[c]);
+		}
 
 		/*
 		 * Create zeros downwards column c by linear combination of row c and
@@ -456,11 +481,11 @@ public class BigIntegerMath {
 				for (int r = c + 1; r < rL; r++) {
 					if (A[r][c].compareTo(BigInteger.ZERO) != 0) {
 						for (int cpr = c; cpr < cL; cpr++) {
-							BigInteger tmp = A[c][cpr];
+							final BigInteger tmp = A[c][cpr];
 							A[c][cpr] = A[r][cpr];
 							A[r][cpr] = tmp;
 						}
-						Rational tmp = x[c];
+						final Rational tmp = x[c];
 						x[c] = x[r];
 						x[r] = tmp;
 						swpd = true;
@@ -471,8 +496,9 @@ public class BigIntegerMath {
 				 * not swapped with a non-zero row: determinant zero and no
 				 * solution
 				 */
-				if (!swpd)
+				if (!swpd) {
 					throw new ArithmeticException("Zero determinant of main matrix");
+				}
 			}
 			/* create zero at A[c+1..cL-1][c] */
 			for (int r = c + 1; r < rL; r++) {
@@ -481,20 +507,22 @@ public class BigIntegerMath {
 				 * not visited again
 				 */
 				for (int cpr = c + 1; cpr < cL; cpr++) {
-					BigInteger tmp = A[c][c].multiply(A[r][cpr]).subtract(A[c][cpr].multiply(A[r][c]));
+					final BigInteger tmp = A[c][c].multiply(A[r][cpr]).subtract(A[c][cpr].multiply(A[r][c]));
 					A[r][cpr] = tmp;
 				}
-				Rational tmp = x[r].multiply(A[c][c]).subtract(x[c].multiply(A[r][c]));
+				final Rational tmp = x[r].multiply(A[c][c]).subtract(x[c].multiply(A[r][c]));
 				x[r] = tmp;
 			}
 		}
-		if (A[cL - 1][cL - 1].compareTo(BigInteger.ZERO) == 0)
+		if (A[cL - 1][cL - 1].compareTo(BigInteger.ZERO) == 0) {
 			throw new ArithmeticException("Zero determinant of main matrix");
+		}
 		/* backward elimination */
 		for (int r = cL - 1; r >= 0; r--) {
 			x[r] = x[r].divide(A[r][r]);
-			for (int rpr = r - 1; rpr >= 0; rpr--)
+			for (int rpr = r - 1; rpr >= 0; rpr--) {
 				x[rpr] = x[rpr].subtract(x[r].multiply(A[rpr][r]));
+			}
 		}
 
 		return x;
@@ -512,7 +540,7 @@ public class BigIntegerMath {
 	 * @author Richard J. Mathar
 	 */
 	static public BigInteger lcm(final BigInteger a, final BigInteger b) {
-		BigInteger g = a.gcd(b);
+		final BigInteger g = a.gcd(b);
 		return a.multiply(b).abs().divide(g);
 	}
 
@@ -529,11 +557,13 @@ public class BigIntegerMath {
 	 * @author Richard J. Mathar
 	 */
 	static public BigInteger valueOf(final Vector<BigInteger> c, final BigInteger x) {
-		if (c.size() == 0)
+		if (c.size() == 0) {
 			return BigInteger.ZERO;
+		}
 		BigInteger res = c.lastElement();
-		for (int i = c.size() - 2; i >= 0; i--)
+		for (int i = c.size() - 2; i >= 0; i--) {
 			res = res.multiply(x).add(c.elementAt(i));
+		}
 		return res;
 	}
 
@@ -552,32 +582,34 @@ public class BigIntegerMath {
 	 *      et al, Num. Funct. Anal. Opt. 10 (5)( 1989) 419-488</a>
 	 */
 	static public Rational centrlFactNumt(int n, int k) throws Error {
-		if (k > n || k < 0 || (k % 2) != (n % 2))
+		if (k > n || k < 0 || (k % 2) != (n % 2)) {
 			return Rational.ZERO;
-		else if (k == n)
+		} else if (k == n) {
 			return Rational.ONE;
-		else {
+		} else {
 			/* Proposition 6.2.6 */
-			Factorial f = new Factorial();
+			final Factorial f = new Factorial();
 			Rational jsum = new Rational(0, 1);
-			int kprime = n - k;
+			final int kprime = n - k;
 			for (int j = 0; j <= kprime; j++) {
 				Rational nusum = new Rational(0, 1);
 				for (int nu = 0; nu <= j; nu++) {
 					Rational t = new Rational(j - 2 * nu, 2);
 					t = t.pow(kprime + j);
 					t = t.multiply(binomial(j, nu));
-					if (nu % 2 != 0)
+					if (nu % 2 != 0) {
 						nusum = nusum.subtract(t);
-					else
+					} else {
 						nusum = nusum.add(t);
+					}
 				}
 				nusum = nusum.divide(f.at(j)).divide(n + j);
 				nusum = nusum.multiply(binomial(2 * kprime, kprime - j));
-				if (j % 2 != 0)
+				if (j % 2 != 0) {
 					jsum = jsum.subtract(nusum);
-				else
+				} else {
 					jsum = jsum.add(nusum);
+				}
 			}
 			return jsum.multiply(k).multiply(binomial(n + kprime, k));
 		}
@@ -597,11 +629,11 @@ public class BigIntegerMath {
 	 *      et al, Num. Funct. Anal. Opt. 10 (5)( 1989) 419-488</a>
 	 */
 	static public Rational centrlFactNumT(int n, int k) {
-		if (k > n || k < 0 || (k % 2) != (n % 2))
+		if (k > n || k < 0 || (k % 2) != (n % 2)) {
 			return Rational.ZERO;
-		else if (k == n)
+		} else if (k == n) {
 			return Rational.ONE;
-		else {
+		} else {
 			/* Proposition 2.1 */
 			return centrlFactNumT(n - 2, k - 2).add(centrlFactNumT(n - 2, k).multiply(new Rational(k * k, 4)));
 		}

src/org/nevec/rjm/BigIntegerPoly.java

@@ -39,10 +39,11 @@ public class BigIntegerPoly implements Cloneable {
 	 */
 	public BigIntegerPoly(final String L) throws NumberFormatException {
 		a = new Vector<>();
-		Scanner sc = new Scanner(L);
+		final Scanner sc = new Scanner(L);
 		sc.useDelimiter(",");
-		while (sc.hasNextBigInteger())
+		while (sc.hasNextBigInteger()) {
 			a.add(sc.nextBigInteger());
+		}
 		simplify();
 		sc.close();
 	} /* ctor */
@@ -66,8 +67,9 @@ public class BigIntegerPoly implements Cloneable {
 	 *            The coefficients a0, a1, a2 etc in a0+a1*x+a2*x^2+...
 	 */
 	public BigIntegerPoly(final BigInteger[] c) {
-		for (int i = 0; i < c.length; i++)
+		for (final BigInteger element : c) {
-			a.add(c[i].add(BigInteger.ZERO));
+			a.add(element.add(BigInteger.ZERO));
+		}
 		simplify();
 	} /* ctor */
 
@@ -87,9 +89,10 @@ public class BigIntegerPoly implements Cloneable {
 	 * @since 2012-03-02
 	 */
 	public RatPoly toRatPoly() {
-		RatPoly bd = new RatPoly();
+		final RatPoly bd = new RatPoly();
-		for (int i = 0; i < a.size(); i++)
+		for (int i = 0; i < a.size(); i++) {
 			bd.set(i, a.elementAt(i));
+		}
 		return bd;
 	} /* toRatPoly */
 
@@ -102,10 +105,11 @@ public class BigIntegerPoly implements Cloneable {
 	 * @return the polynomial coefficient in front of x^n.
 	 */
 	public BigInteger at(final int n) {
-		if (n < a.size())
+		if (n < a.size()) {
 			return (a.elementAt(n));
-		else
+		} else {
 			return (BigInteger.ZERO);
+		}
 	} /* at */
 
 	/**
@@ -118,14 +122,16 @@ public class BigIntegerPoly implements Cloneable {
 	 * @author Richard J. Mathar
 	 */
 	public BigInteger valueOf(final BigInteger x) {
-		if (a.size() == 0)
+		if (a.size() == 0) {
 			return BigInteger.ZERO;
+		}
 		BigInteger res = a.lastElement();
 		/*
 		 * Heron casted form
 		 */
-		for (int i = a.size() - 2; i >= 0; i--)
+		for (int i = a.size() - 2; i >= 0; i--) {
 			res = res.multiply(x).add(a.elementAt(i));
+		}
 		return res;
 	} /* valueOf */
 
@@ -154,9 +160,9 @@ public class BigIntegerPoly implements Cloneable {
 	 *            the new value of the coefficient.
 	 */
 	public void set(final int n, final BigInteger value) {
-		if (n < a.size())
+		if (n < a.size()) {
 			a.set(n, value);
-		else {
+		} else {
 			/*
 			 * fill intermediate powers with coefficients of zero
 			 */
@@ -180,7 +186,7 @@ public class BigIntegerPoly implements Cloneable {
 	 *            the new value of the coefficient.
 	 */
 	public void set(final int n, final int value) {
-		BigInteger val2 = new BigInteger("" + value);
+		final BigInteger val2 = new BigInteger("" + value);
 		set(n, val2);
 	} /* set */
 
@@ -210,9 +216,11 @@ public class BigIntegerPoly implements Cloneable {
 	 *         If the polynomial is identical to 0, 0 is returned.
 	 */
 	public int ldegree() {
-		for (int n = 0; n < a.size(); n++)
+		for (int n = 0; n < a.size(); n++) {
-			if (a.elementAt(n).compareTo(BigInteger.ZERO) != 0)
+			if (a.elementAt(n).compareTo(BigInteger.ZERO) != 0) {
 				return n;
+			}
+		}
 		return 0;
 	} /* ldegree */
 
@@ -227,10 +235,12 @@ public class BigIntegerPoly implements Cloneable {
 	 * @since 2010-08-27
 	 */
 	public BigIntegerPoly multiply(final BigInteger val) {
-		BigIntegerPoly resul = new BigIntegerPoly();
+		final BigIntegerPoly resul = new BigIntegerPoly();
-		if (val.compareTo(BigInteger.ZERO) != 0)
+		if (val.compareTo(BigInteger.ZERO) != 0) {
-			for (int n = 0; n < a.size(); n++)
+			for (int n = 0; n < a.size(); n++) {
 				resul.set(n, a.elementAt(n).multiply(val));
+			}
+		}
 		return resul;
 	} /* multiply */
 
@@ -242,15 +252,16 @@ public class BigIntegerPoly implements Cloneable {
 	 * @return the product of this with the other polynomial
 	 */
 	public BigIntegerPoly multiply(final BigIntegerPoly val) {
-		BigIntegerPoly resul = new BigIntegerPoly();
+		final BigIntegerPoly resul = new BigIntegerPoly();
 		/*
 		 * the degree of the result is the sum of the two degrees.
 		 */
 		final int nmax = degree() + val.degree();
 		for (int n = 0; n <= nmax; n++) {
 			BigInteger coef = BigInteger.ZERO;
-			for (int nleft = 0; nleft <= n; nleft++)
+			for (int nleft = 0; nleft <= n; nleft++) {
 				coef = coef.add(at(nleft).multiply(val.at(n - nleft)));
+			}
 			resul.set(n, coef);
 		}
 		resul.simplify();
@@ -266,11 +277,12 @@ public class BigIntegerPoly implements Cloneable {
 	 */
 	public BigIntegerPoly pow(final int n) throws ArithmeticException {
 		BigIntegerPoly resul = new BigIntegerPoly("1");
-		if (n < 0)
+		if (n < 0) {
 			throw new ArithmeticException("negative polynomial power " + n);
-		else {
+		} else {
-			for (int i = 1; i <= n; i++)
+			for (int i = 1; i <= n; i++) {
 				resul = resul.multiply(this);
+			}
 			resul.simplify();
 			return resul;
 		}
@@ -285,14 +297,14 @@ public class BigIntegerPoly implements Cloneable {
 	 * @since 2010-08-27
 	 */
 	public BigIntegerPoly add(final BigIntegerPoly val) {
-		BigIntegerPoly resul = new BigIntegerPoly();
+		final BigIntegerPoly resul = new BigIntegerPoly();
 		/*
 		 * the degree of the result is the larger of the two degrees (before
 		 * simplify() at least).
 		 */
 		final int nmax = (degree() > val.degree()) ? degree() : val.degree();
 		for (int n = 0; n <= nmax; n++) {
-			BigInteger coef = at(n).add(val.at(n));
+			final BigInteger coef = at(n).add(val.at(n));
 			resul.set(n, coef);
 		}
 		resul.simplify();
@@ -308,14 +320,14 @@ public class BigIntegerPoly implements Cloneable {
 	 * @since 2008-10-25
 	 */
 	public BigIntegerPoly subtract(final BigIntegerPoly val) {
-		BigIntegerPoly resul = new BigIntegerPoly();
+		final BigIntegerPoly resul = new BigIntegerPoly();
 		/*
 		 * the degree of the result is the larger of the two degrees (before
 		 * simplify() at least).
 		 */
 		final int nmax = (degree() > val.degree()) ? degree() : val.degree();
 		for (int n = 0; n <= nmax; n++) {
-			BigInteger coef = at(n).subtract(val.at(n));
+			final BigInteger coef = at(n).subtract(val.at(n));
 			resul.set(n, coef);
 		}
 		resul.simplify();
@@ -334,19 +346,20 @@ public class BigIntegerPoly implements Cloneable {
 	 * @since 2012-03-01
 	 */
 	public BigIntegerPoly[] divideAndRemainder(final BigIntegerPoly val) {
-		BigIntegerPoly[] ret = new BigIntegerPoly[2];
+		final BigIntegerPoly[] ret = new BigIntegerPoly[2];
 		/*
 		 * remove any high-order zeros. note that the clone() operation calls
 		 * simplify().
 		 */
-		BigIntegerPoly valSimpl = val.clone();
+		final BigIntegerPoly valSimpl = val.clone();
-		BigIntegerPoly thisSimpl = clone();
+		final BigIntegerPoly thisSimpl = clone();
 
 		/*
 		 * catch the case with val equal to zero
 		 */
-		if (valSimpl.degree() == 0 && valSimpl.a.firstElement().compareTo(BigInteger.ZERO) == 0)
+		if (valSimpl.degree() == 0 && valSimpl.a.firstElement().compareTo(BigInteger.ZERO) == 0) {
 			throw new ArithmeticException("Division through zero polynomial");
+		}
 		/*
 		 * degree of this smaller than degree of val: remainder is this
 		 */
@@ -363,9 +376,10 @@ public class BigIntegerPoly implements Cloneable {
 			 * polynomial division cannot be done with integer coefficients.
 			 */
 			ret[0] = new BigIntegerPoly();
-			BigInteger[] newc = thisSimpl.a.lastElement().divideAndRemainder(valSimpl.a.lastElement());
+			final BigInteger[] newc = thisSimpl.a.lastElement().divideAndRemainder(valSimpl.a.lastElement());
-			if (newc[1].compareTo(BigInteger.ZERO) != 0)
+			if (newc[1].compareTo(BigInteger.ZERO) != 0) {
 				throw new ArithmeticException("Incompatible leading term in " + this + " / " + val);
+			}
 			ret[0].set(thisSimpl.degree() - valSimpl.degree(), newc[0]);
 
 			/*
@@ -378,10 +392,10 @@ public class BigIntegerPoly implements Cloneable {
 			/*
 			 * any remainder left ?
 			 */
-			if (ret[1].degree() < valSimpl.degree())
+			if (ret[1].degree() < valSimpl.degree()) {
 				;
-			else {
+			} else {
-				BigIntegerPoly rem[] = ret[1].divideAndRemainder(val);
+				final BigIntegerPoly rem[] = ret[1].divideAndRemainder(val);
 				ret[0] = ret[0].add(rem[0]);
 				ret[1] = rem[1];
 			}
@@ -399,13 +413,15 @@ public class BigIntegerPoly implements Cloneable {
 	public String toString() {
 		String str = new String();
 		for (int n = 0; n < a.size(); n++) {
-			if (n == 0)
+			if (n == 0) {
 				str += a.elementAt(n).toString();
-			else
+			} else {
 				str += "," + a.elementAt(n).toString();
+			}
 		}
-		if (str.length() == 0)
+		if (str.length() == 0) {
 			str = "0";
+		}
 		return str;
 	} /* toString */
 
@@ -422,18 +438,21 @@ public class BigIntegerPoly implements Cloneable {
 			final BigInteger num = a.elementAt(n);
 			if (num.compareTo(BigInteger.ZERO) != 0) {
 				str += " ";
-				if (num.compareTo(BigInteger.ZERO) > 0 && n > 0)
+				if (num.compareTo(BigInteger.ZERO) > 0 && n > 0) {
 					str += "+";
+				}
 				str += a.elementAt(n).toString();
 				if (n > 0) {
 					str += "*x";
-					if (n > 1)
+					if (n > 1) {
 						str += "^" + n;
+					}
 				}
 			}
 		}
-		if (str.length() == 0)
+		if (str.length() == 0) {
 			str = "0";
+		}
 		return str;
 	} /* toPString */
 
@@ -443,12 +462,14 @@ public class BigIntegerPoly implements Cloneable {
 	 */
 	protected void simplify() {
 		int n = a.size() - 1;
-		if (n >= 0)
+		if (n >= 0) {
 			while (a.elementAt(n).compareTo(BigInteger.ZERO) == 0) {
 				a.removeElementAt(n);
-				if (--n < 0)
+				if (--n < 0) {
 					break;
+				}
 			}
+		}
 	} /* simplify */
 
 	/**
@@ -464,7 +485,7 @@ public class BigIntegerPoly implements Cloneable {
 			 */
 			return new BigIntegerPoly();
 		} else {
-			BigIntegerPoly d = new BigIntegerPoly();
+			final BigIntegerPoly d = new BigIntegerPoly();
 			for (int i = 1; i <= degree(); i++) {
 				final BigInteger c = a.elementAt(i).multiply(new BigInteger("" + i));
 				d.set(i - 1, c);
@@ -480,9 +501,10 @@ public class BigIntegerPoly implements Cloneable {
 	 * @since 2010-08-27
 	 */
 	public BigIntegerPoly trunc(int newdeg) {
-		BigIntegerPoly t = new BigIntegerPoly();
+		final BigIntegerPoly t = new BigIntegerPoly();
-		for (int i = 0; i <= newdeg; i++)
+		for (int i = 0; i <= newdeg; i++) {
 			t.set(i, at(i));
+		}
 		t.simplify();
 		return t;
 	} /* trunc */
@@ -497,14 +519,16 @@ public class BigIntegerPoly implements Cloneable {
 	 * @since 2010-08-29
 	 */
 	public BigIntegerPoly binomialTInv(int maxdeg) {
-		BigIntegerPoly r = new BigIntegerPoly();
+		final BigIntegerPoly r = new BigIntegerPoly();
 		for (int i = 0; i <= maxdeg; i++) {
 			BigInteger c = BigInteger.ZERO;
-			for (int j = 0; j <= i && j < a.size(); j++)
+			for (int j = 0; j <= i && j < a.size(); j++) {
-				if ((j + i) % 2 != 0)
+				if ((j + i) % 2 != 0) {
 					c = c.subtract(a.elementAt(j).multiply(BigIntegerMath.binomial(i, j)));
-				else
+				} else {
 					c = c.add(a.elementAt(j).multiply(BigIntegerMath.binomial(i, j)));
+				}
+			}
 			r.set(i, c);
 		}
 		r.simplify();
@@ -537,31 +561,34 @@ public class BigIntegerPoly implements Cloneable {
 	 */
 	public Vector<BigInteger> iroots() {
 		/* The vector of the roots */
-		Vector<BigInteger> res = new Vector<>();
+		final Vector<BigInteger> res = new Vector<>();
 
 		/*
 		 * collect the zero
 		 */
-		if (a.firstElement().compareTo(BigInteger.ZERO) == 0)
+		if (a.firstElement().compareTo(BigInteger.ZERO) == 0) {
 			res.add(BigInteger.ZERO);
+		}
 
 		/*
 		 * collect the divisors of the constant element (or the reduced
 		 * polynomial)
 		 */
-		int l = ldegree();
+		final int l = ldegree();
 		if (a.elementAt(l).compareTo(BigInteger.ZERO) != 0) {
-			Vector<BigInteger> cand = BigIntegerMath.divisors(a.elementAt(l).abs());
+			final Vector<BigInteger> cand = BigIntegerMath.divisors(a.elementAt(l).abs());
 
 			/* check the divisors (both signs) */
 			for (int i = 0; i < cand.size(); i++) {
 				BigInteger roo = valueOf(cand.elementAt(i));
-				if (roo.compareTo(BigInteger.ZERO) == 0)
+				if (roo.compareTo(BigInteger.ZERO) == 0) {
 					/* found a root cand[i] */
 					res.add(cand.elementAt(i));
+				}
 				roo = valueOf(cand.elementAt(i).negate());
-				if (roo.compareTo(BigInteger.ZERO) == 0)
+				if (roo.compareTo(BigInteger.ZERO) == 0) {
 					res.add(cand.elementAt(i).negate());
+				}
 			}
 		}
 		return res;
@@ -581,15 +608,16 @@ public class BigIntegerPoly implements Cloneable {
 		/*
 		 * The vector of the factors to be returned
 		 */
-		Vector<BigIntegerPoly> res = new Vector<>();
+		final Vector<BigIntegerPoly> res = new Vector<>();
 
-		if (degree() < 2)
+		if (degree() < 2) {
 			return res;
+		}
 
-		BigInteger bsco = a.firstElement().abs();
+		final BigInteger bsco = a.firstElement().abs();
-		Vector<BigInteger> b = BigIntegerMath.divisors(bsco);
+		final Vector<BigInteger> b = BigIntegerMath.divisors(bsco);
-		BigInteger csco = a.lastElement().abs();
+		final BigInteger csco = a.lastElement().abs();
-		Vector<BigInteger> c = BigIntegerMath.divisors(csco);
+		final Vector<BigInteger> c = BigIntegerMath.divisors(csco);
 
 		/*
 		 * Generate the floating point values of roots. To have some reasonable
@@ -601,8 +629,8 @@ public class BigIntegerPoly implements Cloneable {
 		 * estimate
 		 * and adding 6 safety digits
 		 */
-		RatPoly thisDec = toRatPoly();
+		final RatPoly thisDec = toRatPoly();
-		Vector<BigComplex> roo = thisDec.roots(6 + (int) (0.3 * bsco.bitCount()));
+		final Vector<BigComplex> roo = thisDec.roots(6 + (int) (0.3 * bsco.bitCount()));
 
 		final BigDecimal half = new BigDecimal("0.5");
 
@@ -613,9 +641,9 @@ public class BigIntegerPoly implements Cloneable {
 		 * coefficient.
 		 * Solve z*(c*z+a)=-b or c*z+a = -b/z or -b/z-c*z = some integer a.
 		 */
-		for (BigComplex z : roo) {
+		for (final BigComplex z : roo) {
-			for (BigInteger bco : b)
+			for (final BigInteger bco : b) {
-				for (BigInteger cco : c) {
+				for (final BigInteger cco : c) {
 					/*
 					 * the major reason to avoid the case b=0 is that this would
 					 * require precaution of double counting below. Note that
@@ -624,7 +652,7 @@ public class BigIntegerPoly implements Cloneable {
 					 */
 					if (bco.signum() != 0) {
 						for (int sig = -1; sig <= 1; sig += 2) {
-							BigInteger bcosig = (sig > 0) ? bco : bco.negate();
+							final BigInteger bcosig = (sig > 0) ? bco : bco.negate();
 							/*
 							 * -a = b/z+c*z has real part b*Re(z)/|z|^2+c*Re(z)
 							 * = Re z *( b/|z|^2+c)
@@ -634,22 +662,24 @@ public class BigIntegerPoly implements Cloneable {
 							/*
 							 * convert to a with round-to-nearest
 							 */
-							BigInteger a = negA.negate().add(half).toBigInteger();
+							final BigInteger a = negA.negate().add(half).toBigInteger();
 
 							/*
 							 * test the polynomial remainder. if zero, add the
 							 * term
 							 * to the results.
 							 */
-							BigIntegerPoly dtst = new BigIntegerPoly("" + bcosig + "," + a + "," + cco);
+							final BigIntegerPoly dtst = new BigIntegerPoly("" + bcosig + "," + a + "," + cco);
 							try {
-								BigIntegerPoly[] rm = divideAndRemainder(dtst);
+								final BigIntegerPoly[] rm = divideAndRemainder(dtst);
-								if (rm[1].isZero())
+								if (rm[1].isZero()) {
 									res.add(dtst);
-							} catch (ArithmeticException ex) {}
+								}
+							} catch (final ArithmeticException ex) {}
 						}
 					}
 				}
+			}
 		}
 
 		return res;
@@ -679,16 +709,16 @@ public class BigIntegerPoly implements Cloneable {
 		/*
 		 * this ought be entirely rewritten in terms of the LLL algorithm
 		 */
-		Vector<BigIntegerPoly> fac = new Vector<>();
+		final Vector<BigIntegerPoly> fac = new Vector<>();
 
 		/* collect integer roots (polynomial factors of degree 1) */
-		Vector<BigInteger> r = iroots();
+		final Vector<BigInteger> r = iroots();
 		BigIntegerPoly[] res = new BigIntegerPoly[2];
 		res[0] = this;
-		for (BigInteger i : r) {
+		for (final BigInteger i : r) {
-			int deg = rootDeg(i);
+			final int deg = rootDeg(i);
 			/* construct the factor x-i */
-			BigIntegerPoly f = new BigIntegerPoly("" + i.negate() + ",1");
+			final BigIntegerPoly f = new BigIntegerPoly("" + i.negate() + ",1");
 			for (int mu = 0; mu < deg; mu++) {
 				fac.add(f);
 				res = res[0].divideAndRemainder(f);
@@ -698,21 +728,22 @@ public class BigIntegerPoly implements Cloneable {
 		/*
 		 * collect factors which are polynomials of degree 2
 		 */
-		Vector<BigIntegerPoly> pol2 = i2roots();
+		final Vector<BigIntegerPoly> pol2 = i2roots();
-		for (BigIntegerPoly i : pol2) {
+		for (final BigIntegerPoly i : pol2) {
 			/*
 			 * the internal loop catches cases with higher
 			 * powers of individual polynomials (of actual degree 2 or 4...)
 			 */
 			while (res[0].degree() >= 2) {
 				try {
-					BigIntegerPoly[] dtst = res[0].divideAndRemainder(i);
+					final BigIntegerPoly[] dtst = res[0].divideAndRemainder(i);
 					if (dtst[1].isZero()) {
 						fac.add(i);
 						res = dtst;
-					} else
+					} else {
 						break;
-				} catch (ArithmeticException ex) {
+					}
+				} catch (final ArithmeticException ex) {
 					break;
 				}
 			}
@@ -721,8 +752,9 @@ public class BigIntegerPoly implements Cloneable {
 		/*
 		 * add remaining factor, if not equal to 1
 		 */
-		if (res[0].degree() > 0 || res[0].a.firstElement().compareTo(BigInteger.ONE) != 0)
+		if (res[0].degree() > 0 || res[0].a.firstElement().compareTo(BigInteger.ONE) != 0) {
 			fac.add(res[0]);
+		}
 		return fac;
 	} /* ifactor */
 

src/org/nevec/rjm/BigSurd.java

@@ -60,17 +60,18 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 * @since 2011-02-12
 	 */
 	public BigSurd(Rational a, Rational b) {
-		this.pref = a;
+		pref = a;
 		/*
 		 * reject attempts to use a negative b
 		 */
-		if (b.signum() < 0)
+		if (b.signum() < 0) {
 			throw new ProviderException("Not implemented: imaginary surds");
-		this.disc = b;
+		}
+		disc = b;
 		try {
 			normalize();
 			normalizeG();
-		} catch (Error e) {
+		} catch (final Error e) {
 			e.printStackTrace();
 		}
 	}
@@ -112,8 +113,8 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 */
 	@Override
 	public BigSurd clone() {
-		Rational fclon = pref.clone();
+		final Rational fclon = pref.clone();
-		Rational dclon = disc.clone();
+		final Rational dclon = disc.clone();
 		/*
 		 * the main intent here is to bypass any attempt to reduce the
 		 * discriminant
@@ -121,7 +122,7 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 		 * already done
 		 * in the current copy of the number.
 		 */
-		BigSurd cl = new BigSurd();
+		final BigSurd cl = new BigSurd();
 		cl.pref = fclon;
 		cl.disc = dclon;
 		return cl;
@@ -136,13 +137,14 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 
 	public BigSurdVec add(final BigSurd val) {
 		// zero plus somethings yields something
-		if (signum() == 0)
+		if (signum() == 0) {
 			return new BigSurdVec(val);
-		else if (val.signum() == 0)
+		} else if (val.signum() == 0) {
 			return new BigSurdVec(this);
-		else
+		} else {
 			// let the ctor of BigSurdVec to the work
 			return new BigSurdVec(this, val);
+		}
 	} /* BigSurd.add */
 
 	/**
@@ -190,7 +192,7 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 * @since 2011-02-12
 	 */
 	public BigSurd multiply(final int val) {
-		BigInteger tmp = new BigInteger("" + val);
+		final BigInteger tmp = new BigInteger("" + val);
 		return multiply(tmp);
 	} /* BigSurd.multiply */
 
@@ -216,14 +218,15 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 * @since 2011-02-12
 	 */
 	public BigSurd divide(final BigSurd val) throws Error {
-		if (val.signum() == 0)
+		if (val.signum() == 0) {
 			throw new ArithmeticException("Dividing " + toFancyString() + " through zero.");
+		}
 		return new BigSurd(pref.divide(val.pref), disc.divide(val.disc));
 	} /* BigSurd.divide */
 
 	private String toFancyString() {
-		BigSurd bs = this;
+		final BigSurd bs = this;
-		BigInteger denominator = pref.b;
+		final BigInteger denominator = pref.b;
 		String s = "";
 		if (denominator.compareTo(BigInteger.ONE) != 0) {
 			s += "(";
@@ -233,7 +236,7 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 		} else if (bs.isRational()) {
 			s += bs.toRational().toString();
 		} else {
-			BigInteger numerator = bs.pref.a;
+			final BigInteger numerator = bs.pref.a;
 			if (numerator.compareTo(BigInteger.ONE) != 0) {
 				s += numerator.toString();
 				s += "*";
@@ -262,8 +265,9 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 * @since 2011-02-12
 	 */
 	public BigSurd divide(final BigInteger val) throws Error {
-		if (val.signum() == 0)
+		if (val.signum() == 0) {
 			throw new ArithmeticException("Dividing " + toFancyString() + " through zero.");
+		}
 		return new BigSurd(pref.divide(val), disc);
 	} /* BigSurd.divide */
 
@@ -277,8 +281,9 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 * @since 2011-02-12
 	 */
 	public BigSurd divide(int val) throws Error {
-		if (val == 0)
+		if (val == 0) {
 			throw new ArithmeticException("Dividing " + toFancyString() + " through zero.");
+		}
 		return new BigSurd(pref.divide(val), disc);
 	} /* BigSurd.divide */
 
@@ -293,7 +298,7 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 		 * This is trying to be quick, avoiding normalize(), by toggling
 		 * the sign in a clone()
 		 */
-		BigSurd n = clone();
+		final BigSurd n = clone();
 		n.pref = n.pref.negate();
 		return n;
 	} /* BigSurd.negate */
@@ -325,16 +330,21 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 		 */
 		final int sig = signum();
 		final int sigv = val.signum();
-		if (sig < 0 && sigv >= 0)
+		if (sig < 0 && sigv >= 0) {
 			return -1;
-		if (sig > 0 && sigv <= 0)
+		}
+		if (sig > 0 && sigv <= 0) {
 			return 1;
-		if (sig == 0 && sigv == 0)
+		}
+		if (sig == 0 && sigv == 0) {
 			return 0;
-		if (sig == 0 && sigv > 0)
+		}
+		if (sig == 0 && sigv > 0) {
 			return -1;
-		if (sig == 0 && sigv < 0)
+		}
+		if (sig == 0 && sigv < 0) {
 			return 1;
+		}
 
 		/*
 		 * Work out the cases of equal sign. Compare absolute values by
@@ -345,16 +355,13 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 		final Rational this2 = sqr();
 		final Rational val2 = val.sqr();
 		final int c = this2.compareTo(val2);
-		if (c == 0)
+		if (c == 0) {
 			return 0;
-		/*
+		} else if (sig > 0 && c > 0 || sig < 0 && c < 0) {
-		 * If both values have negative sign, the one with the smaller square is
-		 * the larger number.
-		 */
-		else if (sig > 0 && c > 0 || sig < 0 && c < 0)
 			return 1;
-		else
+		} else {
 			return -1;
+		}
 	} /* BigSurd.compareTo */
 
 	/**
@@ -366,10 +373,11 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 */
 	@Override
 	public String toString() {
-		if (disc.compareTo(Rational.ONE) != 0 && disc.compareTo(Rational.ZERO) != 0)
+		if (disc.compareTo(Rational.ONE) != 0 && disc.compareTo(Rational.ZERO) != 0) {
 			return ("(" + pref.toString() + ")*(" + disc.toString() + ")^(1/2)");
-		else
+		} else {
 			return pref.toString();
+		}
 	} /* BigSurd.toString */
 
 	/**
@@ -383,9 +391,9 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 		 * First compute the square to prevent overflows if the two pieces of
 		 * the prefactor and the discriminant are of very different magnitude.
 		 */
-		Rational p2 = pref.pow(2).multiply(disc);
+		final Rational p2 = pref.pow(2).multiply(disc);
 		System.out.println("dv sq " + p2.toString());
-		double res = p2.doubleValue();
+		final double res = p2.doubleValue();
 		System.out.println("dv sq " + res);
 		return (pref.signum() >= 0) ? Math.sqrt(res) : -Math.sqrt(res);
 	} /* BigSurd.doubleValue */
@@ -428,10 +436,11 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 	 * @since 2012-02-15
 	 */
 	public Rational toRational() {
-		if (isRational())
+		if (isRational()) {
 			return pref;
-		else
+		} else {
 			throw new ArithmeticException("Undefined conversion " + toFancyString() + " to Rational.");
+		}
 	} /* BigSurd.toRational */
 
 	/**
@@ -463,7 +472,7 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 			/*
 			 * square-free part of the numerator: numer = numC*some^2
 			 */
-			BigInteger numC = BigIntegerMath.core(disc.numer());
+			final BigInteger numC = BigIntegerMath.core(disc.numer());
 			/*
 			 * extract the perfect square of the numerator
 			 */
@@ -478,14 +487,15 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 			 */
 			pref = pref.multiply(sqf);
 
-			BigInteger denC = BigIntegerMath.core(disc.denom());
+			final BigInteger denC = BigIntegerMath.core(disc.denom());
 			sq = disc.denom().divide(denC);
 			sqf = BigIntegerMath.isqrt(sq);
 			pref = pref.divide(sqf);
 
 			disc = new Rational(numC, denC);
-		} else
+		} else {
 			pref = Rational.ZERO;
+		}
 	} /* BigSurd.normalize */
 
 	/**
@@ -544,13 +554,13 @@ public class BigSurd implements Cloneable, Comparable<BigSurd> {
 		/*
 		 * first the square root of the discriminant
 		 */
-		BigDecimal sqrdis = BigDecimalMath.sqrt(disc.BigDecimalValue(locmc), locmc);
+		final BigDecimal sqrdis = BigDecimalMath.sqrt(disc.BigDecimalValue(locmc), locmc);
 		/*
 		 * Then multiply by the prefactor. If sqrdis is a terminating decimal
 		 * fraction,
 		 * we prevent early truncation of the result by truncating later.
 		 */
-		BigDecimal res = sqrdis.multiply(pref.BigDecimalValue(mc));
+		final BigDecimal res = sqrdis.multiply(pref.BigDecimalValue(mc));
 		return BigDecimalMath.scalePrec(res, mc);
 	} /* BigDecimalValue */
 

src/org/nevec/rjm/BigSurdVec.java

@@ -69,7 +69,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		terms.add(b);
 		try {
 			normalize();
-		} catch (Error e) {
+		} catch (final Error e) {
 			// TODO Auto-generated catch block
 			e.printStackTrace();
 		}
@@ -87,16 +87,17 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		/*
 		 * nothing to be done if at most one term
 		 */
-		if (terms.size() <= 1)
+		if (terms.size() <= 1) {
 			return;
+		}
 
-		Vector<BigSurd> newter = new Vector<>();
+		final Vector<BigSurd> newter = new Vector<>();
 		newter.add(terms.firstElement());
 		/*
 		 * add j-th element to the existing vector and combine were possible
 		 */
 		for (int j = 1; j < terms.size(); j++) {
-			BigSurd todo = terms.elementAt(j);
+			final BigSurd todo = terms.elementAt(j);
 			boolean merged = false;
 			for (int ex = 0; ex < newter.size(); ex++) {
 				BigSurd v = newter.elementAt(ex);
@@ -105,16 +106,16 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 				 * rational number is needed. Replaces v with v+todo = v*(1+r)
 				 * if this reduction works.
 				 */
-				BigSurd r = todo.divide(v);
+				final BigSurd r = todo.divide(v);
 				if (r.isRational()) {
 					/* compute r+1 */
-					Rational newpref = r.toRational().add(1);
+					final Rational newpref = r.toRational().add(1);
 					/*
 					 * eliminate accidental zeros; overwrite with v*(1+r).
 					 */
-					if (newpref.compareTo(Rational.ZERO) == 0)
+					if (newpref.compareTo(Rational.ZERO) == 0) {
 						newter.removeElementAt(ex);
-					else {
+					} else {
 						v = v.multiply(newpref);
 						newter.setElementAt(v, ex);
 					}
@@ -125,8 +126,9 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 			/*
 			 * append if none of the existing elements matched
 			 */
-			if (!merged)
+			if (!merged) {
 				newter.add(todo);
+			}
 		}
 
 		/* overwrite old version */
@@ -148,7 +150,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		try {
 			diff = this.subtract(oth);
 			return diff.signum();
-		} catch (Error e) {
+		} catch (final Error e) {
 			// TODO Auto-generated catch block
 			e.printStackTrace();
 			return 0;
@@ -168,34 +170,40 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		 * the case of zero is unique, because no (reduced) vector of surds
 		 * other than the one element 0 itself can add/subtract to zero.
 		 */
-		if (terms.size() == 0)
+		if (terms.size() == 0) {
 			return 0;
+		}
 
 		/*
 		 * if there is one term: forward to the signum function of BigSurd
 		 */
-		if (terms.size() == 1)
+		if (terms.size() == 1) {
 			return terms.firstElement().signum();
+		}
 
 		/*
 		 * if all terms have a common sign: take that one offsig is the index of
 		 * the first "offending" term in the sense that its sign doese not agree
 		 * with the term[0].
 		 */
-		int sig0 = terms.elementAt(0).signum();
+		final int sig0 = terms.elementAt(0).signum();
 		int offsig = 1;
-		for (; offsig < terms.size(); offsig++)
+		for (; offsig < terms.size(); offsig++) {
-			if (terms.elementAt(offsig).signum() != sig0)
+			if (terms.elementAt(offsig).signum() != sig0) {
 				break;
-		if (offsig >= terms.size())
+			}
+		}
+		if (offsig >= terms.size()) {
 			return sig0;
+		}
 
 		/*
 		 * if there are two terms (now known to have different sign): forward to
 		 * the comparison of the two elements as BigSurds
 		 */
-		if (terms.size() == 2)
+		if (terms.size() == 2) {
 			return terms.elementAt(0).compareTo(terms.elementAt(1).negate());
+		}
 
 		/*
 		 * if there are three terms, move the one with the offending sign to the
@@ -206,10 +214,11 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		 */
 		if (terms.size() == 3) {
 			BigSurdVec lhs;
-			if (offsig == 2)
+			if (offsig == 2) {
 				lhs = new BigSurdVec(terms.elementAt(0), terms.elementAt(1));
-			else
+			} else {
 				lhs = new BigSurdVec(terms.elementAt(0), terms.elementAt(2));
+			}
 			lhs = lhs.sqr();
 			/*
 			 * Strange line: this line isn't used, but it's present in this
@@ -223,13 +232,14 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 			 * 
 			 * 
 			 */
-			if (lhs.compareTo(lhs) > 0)
+			if (lhs.compareTo(lhs) > 0) {
 				/*
 				 * dominating sign was t(0)+t(offbar)
 				 */
 				return terms.elementAt(0).signum();
-			else
+			} else {
 				return terms.elementAt(offsig).signum();
+			}
 		}
 
 		/*
@@ -252,9 +262,9 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		/*
 		 * simple cases with one term forwarded to the BigSurd class
 		 */
-		if (terms.size() == 0)
+		if (terms.size() == 0) {
 			return BigDecimal.ZERO;
-		else if (terms.size() == 1) {
+		} else if (terms.size() == 1) {
 			return terms.firstElement().BigDecimalValue(mc);
 		}
 
@@ -263,18 +273,20 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		 * until we are stable to the required result. Keep the old (less
 		 * precise) estimate in res[0], and the newer, more precise in res[1].
 		 */
-		BigDecimal[] res = new BigDecimal[2];
+		final BigDecimal[] res = new BigDecimal[2];
 		res[0] = BigDecimal.ZERO;
 		for (int addpr = 1;; addpr += 3) {
-			MathContext locmc = new MathContext(mc.getPrecision() + addpr, mc.getRoundingMode());
+			final MathContext locmc = new MathContext(mc.getPrecision() + addpr, mc.getRoundingMode());
 			res[1] = BigDecimal.ZERO;
-			for (BigSurd j : terms)
+			for (final BigSurd j : terms) {
 				res[1] = BigDecimalMath.addRound(res[1], j.BigDecimalValue(locmc));
+			}
 			if (addpr > 1) {
-				BigDecimal err = res[1].subtract(res[0]).abs();
+				final BigDecimal err = res[1].subtract(res[0]).abs();
-				int prec = BigDecimalMath.err2prec(res[1], err);
+				final int prec = BigDecimalMath.err2prec(res[1], err);
-				if (prec > mc.getPrecision())
+				if (prec > mc.getPrecision()) {
 					break;
+				}
 			}
 			res[0] = res[1];
 		}
@@ -288,7 +300,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 * @return A truncated version with the precision described by mc
 	 */
 	public double doubleValue() {
-		BigDecimal bd = BigDecimalValue(MathContext.DECIMAL128);
+		final BigDecimal bd = BigDecimalValue(MathContext.DECIMAL128);
 		return bd.doubleValue();
 	} /* doubleValue */
 
@@ -298,7 +310,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 * @return A truncated version with the precision described by mc
 	 */
 	public double floatValue() {
-		BigDecimal bd = BigDecimalValue(MathContext.DECIMAL64);
+		final BigDecimal bd = BigDecimalValue(MathContext.DECIMAL64);
 		return bd.floatValue();
 	} /* floatValue */
 
@@ -311,16 +323,16 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 * @throws Error
 	 */
 	public BigSurdVec add(final BigSurdVec val) throws Error {
-		BigSurdVec sum = new BigSurdVec();
+		final BigSurdVec sum = new BigSurdVec();
 		/*
 		 * concatenate the vectors and eliminate common overlaps
 		 */
-		for (BigSurd term : terms) {
+		for (final BigSurd term : terms) {
 			if (term.compareTo(BigSurd.ZERO) != 0) {
 				sum.terms.add(term);
 			}
 		}
-		for (BigSurd term : val.terms) {
+		for (final BigSurd term : val.terms) {
 			if (term.compareTo(BigSurd.ZERO) != 0) {
 				sum.terms.add(term);
 			}
@@ -338,7 +350,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 * @throws Error
 	 */
 	public BigSurdVec add(final BigSurd val) throws Error {
-		BigSurdVec sum = new BigSurdVec();
+		final BigSurdVec sum = new BigSurdVec();
 		/*
 		 * concatenate the vectors and eliminate common overlaps
 		 */
@@ -357,13 +369,14 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 * @throws Error
 	 */
 	public BigSurdVec subtract(final BigSurdVec val) throws Error {
-		BigSurdVec sum = new BigSurdVec();
+		final BigSurdVec sum = new BigSurdVec();
 		/*
 		 * concatenate the vectors and eliminate common overlaps
 		 */
 		sum.terms.addAll(terms);
-		for (BigSurd s : val.terms)
+		for (final BigSurd s : val.terms) {
 			sum.terms.add(s.negate());
+		}
 		sum.normalize();
 		return sum;
 	} /* subtract */
@@ -377,7 +390,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 * @throws Error
 	 */
 	public BigSurdVec subtract(final BigSurd val) throws Error {
-		BigSurdVec sum = new BigSurdVec();
+		final BigSurdVec sum = new BigSurdVec();
 		/*
 		 * concatenate the vectors and eliminate common overlaps
 		 */
@@ -397,9 +410,10 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		/*
 		 * accumulate the negated elements of term one by one
 		 */
-		BigSurdVec resul = new BigSurdVec();
+		final BigSurdVec resul = new BigSurdVec();
-		for (BigSurd s : terms)
+		for (final BigSurd s : terms) {
 			resul.terms.add(s.negate());
+		}
 		/*
 		 * no normalization step here, because the negation of all terms does
 		 * not introduce new common factors
@@ -419,12 +433,15 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		 * Binomial expansion. First the sum of the terms squared, then 2 times
 		 * the mixed products.
 		 */
-		BigSurdVec resul = new BigSurdVec();
+		final BigSurdVec resul = new BigSurdVec();
-		for (int i = 0; i < terms.size(); i++)
+		for (int i = 0; i < terms.size(); i++) {
 			resul.terms.add(new BigSurd(terms.elementAt(i).sqr(), Rational.ONE));
-		for (int i = 0; i < terms.size() - 1; i++)
+		}
-			for (int j = i + 1; j < terms.size(); j++)
+		for (int i = 0; i < terms.size() - 1; i++) {
+			for (int j = i + 1; j < terms.size(); j++) {
 				resul.terms.add(terms.elementAt(i).multiply(terms.elementAt(j)).multiply(2));
+			}
+		}
 		resul.normalize();
 		return resul;
 	} /* sqr */
@@ -439,28 +456,30 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 * @since 2011-02-12
 	 */
 	public BigSurdVec multiply(final BigSurd val) throws Error {
-		BigSurdVec resul = new BigSurdVec();
+		final BigSurdVec resul = new BigSurdVec();
-		for (BigSurd s : terms)
+		for (final BigSurd s : terms) {
 			resul.terms.add(s.multiply(val));
+		}
 		resul.normalize();
 		return resul;
 	} /* multiply */
 
 	public BigSurdVec multiply(final BigSurdVec val) throws Error {
 		BigSurdVec resul = new BigSurdVec();
-		for (BigSurd s : terms) {
+		for (final BigSurd s : terms) {
 			resul.terms.add(s);
 		}
-		for (BigSurd s : val.terms) {
+		for (final BigSurd s : val.terms) {
 			resul = resul.multiply(s);
 		}
 		return resul;
 	} /* multiply */
 
 	public BigSurdVec divide(final BigSurd val) throws Error {
-		BigSurdVec resul = new BigSurdVec();
+		final BigSurdVec resul = new BigSurdVec();
-		for (BigSurd s : terms)
+		for (final BigSurd s : terms) {
 			resul.terms.add(s.divide(val));
+		}
 		resul.normalize();
 		return resul;
 	} /* multiply */
@@ -468,7 +487,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	public BigSurdVec divide(final BigSurdVec val) throws Error {
 		BigSurdVec resul = new BigSurdVec();
 		resul.terms = terms;
-		for (BigSurd s : val.terms) {
+		for (final BigSurd s : val.terms) {
 			resul = resul.divide(s);
 		}
 		return resul;
@@ -482,7 +501,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 */
 	public boolean isRational() {
 		boolean val = false;
-		for (BigSurd s : terms) {
+		for (final BigSurd s : terms) {
 			val = s.isRational();
 			if (val == false) {
 				break;
@@ -499,7 +518,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 */
 	public boolean isBigInteger() {
 		boolean val = false;
-		for (BigSurd s : terms) {
+		for (final BigSurd s : terms) {
 			val = s.isBigInteger();
 			if (val == false) {
 				break;
@@ -515,9 +534,10 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 */
 	public Rational toRational() {
 		Rational rat = Rational.ZERO;
-		if (isRational() == false)
+		if (isRational() == false) {
 			throw new ArithmeticException("Undefined conversion " + toString() + " to Rational.");
-		for (BigSurd s : terms) {
+		}
+		for (final BigSurd s : terms) {
 			rat = rat.add(s.pref);
 		}
 		return rat;
@@ -530,9 +550,10 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 */
 	public BigInteger toBigInteger() {
 		BigDecimal tmp = BigDecimal.ZERO.setScale(Utils.scale, Utils.scaleMode);
-		if (isBigInteger() == false)
+		if (isBigInteger() == false) {
 			throw new ArithmeticException("Undefined conversion " + toString() + " to Rational.");
-		for (BigSurd s : terms) {
+		}
+		for (final BigSurd s : terms) {
 			tmp = BigDecimalMath.addRound(tmp, s.pref.BigDecimalValue(new MathContext(Utils.scale, Utils.scaleMode2)));
 		}
 		return tmp.toBigInteger();
@@ -545,7 +566,7 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	 */
 	public BigDecimal toBigDecimal() {
 		BigDecimal tmp = BigDecimal.ZERO.setScale(Utils.scale, Utils.scaleMode);
-		for (BigSurd s : terms) {
+		for (final BigSurd s : terms) {
 			tmp = BigDecimalMath.addRound(tmp, s.BigDecimalValue(new MathContext(Utils.scale, Utils.scaleMode2)));
 		}
 		return tmp;
@@ -563,14 +584,15 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 		/*
 		 * simple cases with one term forwarded to the BigSurd class
 		 */
-		if (terms.size() == 0)
+		if (terms.size() == 0) {
 			return new String("0");
-		else {
+		} else {
 			String s = new String();
 			for (int t = 0; t < terms.size(); t++) {
-				BigSurd bs = terms.elementAt(t);
+				final BigSurd bs = terms.elementAt(t);
-				if (bs.signum() > 0)
+				if (bs.signum() > 0) {
 					s += "+";
+				}
 				s += bs.toString();
 			}
 			return s;
@@ -578,9 +600,9 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 	} /* toString */
 
 	public String toFancyString() {
-		if (terms.size() == 0)
+		if (terms.size() == 0) {
 			return new String("0");
-		else {
+		} else {
 			BigInteger denominator = BigInteger.ONE;
 			for (int i = 0; i < terms.size(); i++) {
 				denominator = denominator.multiply(terms.elementAt(i).pref.b);
@@ -590,15 +612,16 @@ public class BigSurdVec implements Comparable<BigSurdVec> {
 				s += "(";
 			}
 			for (int t = 0; t < terms.size(); t++) {
-				BigSurd bs = terms.elementAt(t);
+				final BigSurd bs = terms.elementAt(t);
-				if (bs.signum() > 0 && t > 0)
+				if (bs.signum() > 0 && t > 0) {
 					s += "+";
+				}
 				if (bs.isBigInteger()) {
 					s += bs.BigDecimalValue(new MathContext(Utils.scale, Utils.scaleMode2)).toBigInteger().toString();
 				} else if (bs.isRational()) {
 					s += bs.toRational().toString();
 				} else {
-					BigInteger numerator = bs.pref.multiply(denominator).numer();
+					final BigInteger numerator = bs.pref.multiply(denominator).numer();
 					if (numerator.compareTo(BigInteger.ONE) != 0) {
 						s += numerator.toString();
 						s += "*";

src/org/nevec/rjm/Euler.java

@@ -38,20 +38,22 @@ public class Euler {
 		while (n >= a.size()) {
 			BigInteger val = BigInteger.ZERO;
 			boolean sigPos = true;
-			int thisn = a.size();
+			final int thisn = a.size();
 			for (int i = thisn - 1; i > 0; i--) {
 				BigInteger f = new BigInteger("" + a.elementAt(i).toString());
 				f = f.multiply(BigIntegerMath.binomial(2 * thisn, 2 * i));
-				if (sigPos)
+				if (sigPos) {
 					val = val.add(f);
-				else
+				} else {
 					val = val.subtract(f);
+				}
 				sigPos = !sigPos;
 			}
-			if (thisn % 2 == 0)
+			if (thisn % 2 == 0) {
 				val = val.subtract(BigInteger.ONE);
-			else
+			} else {
 				val = val.add(BigInteger.ONE);
+			}
 			a.add(val);
 		}
 	}

src/org/nevec/rjm/EulerPhi.java

@@ -36,16 +36,18 @@ public class EulerPhi {
 	 * @return phi(n)
 	 */
 	public BigInteger at(BigInteger n) {
-		if (n.compareTo(BigInteger.ZERO) <= 0)
+		if (n.compareTo(BigInteger.ZERO) <= 0) {
 			throw new ArithmeticException("negative argument " + n + " of EulerPhi");
-		Ifactor prFact = new Ifactor(n);
+		}
+		final Ifactor prFact = new Ifactor(n);
 		BigInteger phi = n;
-		if (n.compareTo(BigInteger.ONE) > 0)
+		if (n.compareTo(BigInteger.ONE) > 0) {
 			for (int i = 0; i < prFact.primeexp.size(); i += 2) {
-				BigInteger p = new BigInteger(prFact.primeexp.elementAt(i).toString());
+				final BigInteger p = new BigInteger(prFact.primeexp.elementAt(i).toString());
-				BigInteger p_1 = p.subtract(BigInteger.ONE);
+				final BigInteger p_1 = p.subtract(BigInteger.ONE);
 				phi = phi.multiply(p_1).divide(p);
 			}
+		}
 		return phi;
 	} /* at */
 
@@ -57,8 +59,8 @@ public class EulerPhi {
 	 * @since 2006-08-14
 	 */
 	public static void main(String[] args) throws ArithmeticException {
-		EulerPhi a = new EulerPhi();
+		final EulerPhi a = new EulerPhi();
-		int n = (new Integer(args[0])).intValue();
+		final int n = (new Integer(args[0])).intValue();
 		System.out.println("phi(" + n + ") = " + a.at(n));
 	}
 } /* EulerPhi */

src/org/nevec/rjm/Harmonic.java

@@ -23,9 +23,9 @@ public class Harmonic {
 	 *         For values of n less than 1, zero is returned.
 	 */
 	public Rational at(int n) {
-		if (n < 1)
+		if (n < 1) {
 			return (new Rational(0, 1));
-		else {
+		} else {
 			/*
 			 * start with 1 as the result
 			 */
@@ -34,8 +34,9 @@ public class Harmonic {
 			/*
 			 * add 1/i for i=2..n
 			 */
-			for (int i = 2; i <= n; i++)
+			for (int i = 2; i <= n; i++) {
 				a = a.add(new Rational(1, i));
+			}
 			return a;
 		}
 	}

src/org/nevec/rjm/Ifactor.java

@@ -48,7 +48,7 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		primeexp = new Vector<>();
 		if (number > 1) {
 			int primindx = 0;
-			Prime primes = new Prime();
+			final Prime primes = new Prime();
 			/*
 			 * Test division against all primes.
 			 */
@@ -57,12 +57,13 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 				/*
 				 * primindx=0 refers to 2, =1 to 3, =2 to 5, =3 to 7 etc
 				 */
-				int p = primes.at(primindx).intValue();
+				final int p = primes.at(primindx).intValue();
 				while (number % p == 0) {
 					ex++;
 					number /= p;
-					if (number == 1)
+					if (number == 1) {
 						break;
+					}
 				}
 				if (ex > 0) {
 					primeexp.add(new Integer(p));
@@ -92,18 +93,19 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 			primeexp.add(new Integer(0));
 		} else {
 			int primindx = 0;
-			Prime primes = new Prime();
+			final Prime primes = new Prime();
 			/*
 			 * Test for division against all primes.
 			 */
 			while (number.compareTo(BigInteger.ONE) == 1) {
 				int ex = 0;
-				BigInteger p = primes.at(primindx);
+				final BigInteger p = primes.at(primindx);
 				while (number.remainder(p).compareTo(BigInteger.ZERO) == 0) {
 					ex++;
 					number = number.divide(p);
-					if (number.compareTo(BigInteger.ONE) == 0)
+					if (number.compareTo(BigInteger.ONE) == 0) {
 						break;
+					}
 				}
 				if (ex > 0) {
 					primeexp.add(new Integer(p.intValue()));
@@ -128,19 +130,20 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		primeexp = new Vector<>(2 * pows.size());
 		if (pows.size() > 0) {
 			n = BigInteger.ONE;
-			Prime primes = new Prime();
+			final Prime primes = new Prime();
 			/*
 			 * Build the full number by the product of all powers of the primes.
 			 */
 			for (int primindx = 0; primindx < pows.size(); primindx++) {
-				int ex = pows.elementAt(primindx).intValue();
+				final int ex = pows.elementAt(primindx).intValue();
 				final BigInteger p = primes.at(primindx);
 				n = n.multiply(p.pow(ex));
 				primeexp.add(new Integer(p.intValue()));
 				primeexp.add(new Integer(ex));
 			}
-		} else
+		} else {
 			n = BigInteger.ZERO;
+		}
 	} /* Ifactor */
 
 	/**
@@ -167,7 +170,7 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		 * Vector<Integer> p = (Vector<Integer>)primeexp.clone();
 		 *
 		 */
-		Ifactor cl = new Ifactor(0);
+		final Ifactor cl = new Ifactor(0);
 		cl.n = new BigInteger("" + n);
 		return cl;
 	} /* Ifactor.clone */
@@ -267,7 +270,7 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 * @return the product, gcd or lcm of both numbers.
 	 */
 	protected Ifactor multGcdLcm(final Ifactor oth, int type) {
-		Ifactor prod = new Ifactor(0);
+		final Ifactor prod = new Ifactor(0);
 		/*
 		 * skip the case where 0*something =0, falling thru to the empty
 		 * representation for 0
@@ -278,19 +281,19 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 			 * Cases of lcm(1, something) return something.
 			 * Cases of gcd(1, something) return 1.
 			 */
-			if (primeexp.firstElement().intValue() == 1 && type == 0)
+			if (primeexp.firstElement().intValue() == 1 && type == 0) {
 				return oth;
-			else if (primeexp.firstElement().intValue() == 1 && type == 2)
+			} else if (primeexp.firstElement().intValue() == 1 && type == 2) {
 				return oth;
-			else if (primeexp.firstElement().intValue() == 1 && type == 1)
+			} else if (primeexp.firstElement().intValue() == 1 && type == 1) {
 				return this;
-			else if (oth.primeexp.firstElement().intValue() == 1 && type == 0)
+			} else if (oth.primeexp.firstElement().intValue() == 1 && type == 0) {
 				return this;
-			else if (oth.primeexp.firstElement().intValue() == 1 && type == 2)
+			} else if (oth.primeexp.firstElement().intValue() == 1 && type == 2) {
 				return this;
-			else if (oth.primeexp.firstElement().intValue() == 1 && type == 1)
+			} else if (oth.primeexp.firstElement().intValue() == 1 && type == 1) {
 				return oth;
-			else {
+			} else {
 				int idxThis = 0;
 				int idxOth = 0;
 				switch (type) {
@@ -417,10 +420,11 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		/*
 		 * avoid refactorization if oth is zero...
 		 */
-		if (oth.compareTo(BigInteger.ZERO) != 0)
+		if (oth.compareTo(BigInteger.ZERO) != 0) {
 			return new Ifactor(n.add(oth));
-		else
+		} else {
 			return this;
+		}
 	} /* Ifactor.add */
 
 	/**
@@ -434,22 +438,23 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		/*
 		 * three simple cases first
 		 */
-		if (exponent < 0)
+		if (exponent < 0) {
 			throw new ArithmeticException("Cannot raise " + toString() + " to negative " + exponent);
-		else if (exponent == 0)
+		} else if (exponent == 0) {
 			return new Ifactor(1);
-		else if (exponent == 1)
+		} else if (exponent == 1) {
 			return this;
+		}
 
 		/*
 		 * general case, the vector with the prime factor powers, which are
 		 * component-wise
 		 * exponentiation of the individual prime factor powers.
 		 */
-		Ifactor pows = new Ifactor(0);
+		final Ifactor pows = new Ifactor(0);
 		for (int i = 0; i < primeexp.size(); i += 2) {
-			Integer p = primeexp.elementAt(i);
+			final Integer p = primeexp.elementAt(i);
-			int ex = primeexp.elementAt(i + 1).intValue();
+			final int ex = primeexp.elementAt(i + 1).intValue();
 			pows.primeexp.add(p);
 			pows.primeexp.add(new Integer(ex * exponent));
 		}
@@ -469,24 +474,25 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 * @since 2009-05-18
 	 */
 	public Rational root(final int r) throws ArithmeticException, Error {
-		if (r == 0)
+		if (r == 0) {
 			throw new ArithmeticException("Cannot pull zeroth root of " + toString());
-		else if (r < 0) {
+		} else if (r < 0) {
 			/*
 			 * a^(-1/b)= 1/(a^(1/b))
 			 */
 			final Rational invRoot = root(-r);
 			return Rational.ONE.divide(invRoot);
 		} else {
-			BigInteger pows = BigInteger.ONE;
+			final BigInteger pows = BigInteger.ONE;
 			for (int i = 0; i < primeexp.size(); i += 2) {
 				/*
 				 * all exponents must be multiples of r to succeed (that is, to
 				 * stay in the range of rational results).
 				 */
-				int ex = primeexp.elementAt(i + 1).intValue();
+				final int ex = primeexp.elementAt(i + 1).intValue();
-				if (ex % r != 0)
+				if (ex % r != 0) {
 					throw new ArithmeticException("Cannot pull " + r + "th root of " + toString());
+				}
 
 				pows.multiply(new BigInteger("" + primeexp.elementAt(i)).pow(ex / r));
 			}
@@ -512,18 +518,19 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		 * multiplied
 		 * by 1 or by a product that contains the factors p1..py.
 		 */
-		Vector<BigInteger> d = new Vector<>();
+		final Vector<BigInteger> d = new Vector<>();
-		if (n.compareTo(BigInteger.ZERO) == 0)
+		if (n.compareTo(BigInteger.ZERO) == 0) {
 			return d;
+		}
 		d.add(BigInteger.ONE);
 		if (n.compareTo(BigInteger.ONE) > 0) {
 			/* Computes sigmaIncopml(p1^e*p2^e2...*py^ey) */
-			Ifactor dp = dropPrime();
+			final Ifactor dp = dropPrime();
 
 			/* get ez */
 			final int ez = primeexp.lastElement().intValue();
 
-			Vector<BigInteger> partd = dp.divisors();
+			final Vector<BigInteger> partd = dp.divisors();
 
 			/* obtain pz by lookup in the prime list */
 			final BigInteger pz = new BigInteger(primeexp.elementAt(primeexp.size() - 2).toString());
@@ -532,12 +539,14 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 			 * the output contains all products of the form partd[]*pz^ez, ez>0,
 			 * and with the exception of the 1, all these are appended.
 			 */
-			for (int i = 1; i < partd.size(); i++)
+			for (int i = 1; i < partd.size(); i++) {
 				d.add(partd.elementAt(i));
+			}
 			for (int e = 1; e <= ez; e++) {
 				final BigInteger pzez = pz.pow(e);
-				for (int i = 0; i < partd.size(); i++)
+				for (int i = 0; i < partd.size(); i++) {
 					d.add(partd.elementAt(i).multiply(pzez));
+				}
 			}
 		}
 		Collections.sort(d);
@@ -563,29 +572,29 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		 * the question is whether keeping a factorization is worth the effort
 		 * or whether one should simply multiply these to return a BigInteger...
 		 */
-		if (n.compareTo(BigInteger.ONE) == 0)
+		if (n.compareTo(BigInteger.ONE) == 0) {
 			return ONE;
-		else if (n.compareTo(BigInteger.ZERO) == 0)
+		} else if (n.compareTo(BigInteger.ZERO) == 0) {
 			return ZERO;
-		else {
+		} else {
 			/*
 			 * multiplicative: sigma_k(p^e) = [p^(k*(e+1))-1]/[p^k-1]
 			 * sigma_0(p^e) = e+1.
 			 */
 			Ifactor resul = Ifactor.ONE;
 			for (int i = 0; i < primeexp.size(); i += 2) {
-				int ex = primeexp.elementAt(i + 1).intValue();
+				final int ex = primeexp.elementAt(i + 1).intValue();
-				if (k == 0)
+				if (k == 0) {
 					resul = resul.multiply(ex + 1);
-				else {
+				} else {
-					Integer p = primeexp.elementAt(i);
+					final Integer p = primeexp.elementAt(i);
-					BigInteger num = (new BigInteger(p.toString())).pow(k * (ex + 1)).subtract(BigInteger.ONE);
+					final BigInteger num = (new BigInteger(p.toString())).pow(k * (ex + 1)).subtract(BigInteger.ONE);
-					BigInteger deno = (new BigInteger(p.toString())).pow(k).subtract(BigInteger.ONE);
+					final BigInteger deno = (new BigInteger(p.toString())).pow(k).subtract(BigInteger.ONE);
 					/*
 					 * This division is of course exact, no remainder
 					 * The costly prime factorization is hidden here.
 					 */
-					Ifactor f = new Ifactor(num.divide(deno));
+					final Ifactor f = new Ifactor(num.divide(deno));
 					resul = resul.multiply(f);
 				}
 			}
@@ -608,8 +617,9 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		/*
 		 * the cases n==1 or n ==0
 		 */
-		if (n.compareTo(BigInteger.ONE) <= 0)
+		if (n.compareTo(BigInteger.ONE) <= 0) {
 			return this;
+		}
 
 		/*
 		 * The cases n>1
@@ -617,13 +627,13 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		 * the vector with the new prime factor powers, which contain the
 		 * old prime factor powers up to but not including the last one.
 		 */
-		Ifactor pows = new Ifactor(0);
+		final Ifactor pows = new Ifactor(0);
 		pows.n = BigInteger.ONE;
 		for (int i = 0; i < primeexp.size() - 2; i += 2) {
 			pows.primeexp.add(primeexp.elementAt(i));
 			pows.primeexp.add(primeexp.elementAt(i + 1));
-			BigInteger p = new BigInteger(primeexp.elementAt(i).toString());
+			final BigInteger p = new BigInteger(primeexp.elementAt(i).toString());
-			int ex = primeexp.elementAt(i + 1).intValue();
+			final int ex = primeexp.elementAt(i + 1).intValue();
 			pows.n = pows.n.multiply(p.pow(ex));
 		}
 		return pows;
@@ -639,8 +649,9 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 		 * check the exponents, located at the odd-indexed positions
 		 */
 		for (int i = 1; i < primeexp.size(); i += 2) {
-			if (primeexp.elementAt(i).intValue() % 2 != 0)
+			if (primeexp.elementAt(i).intValue() % 2 != 0) {
 				return false;
+			}
 		}
 		return true;
 	} /* Ifactor.issquare */
@@ -652,8 +663,9 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 */
 	public int bigomega() {
 		int resul = 0;
-		for (int i = 1; i < primeexp.size(); i += 2)
+		for (int i = 1; i < primeexp.size(); i += 2) {
 			resul += primeexp.elementAt(i).intValue();
+		}
 		return (resul);
 	} /* Ifactor.bigomega */
 
@@ -675,9 +687,11 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 */
 	public BigInteger core() {
 		BigInteger resul = BigInteger.ONE;
-		for (int i = 0; i < primeexp.size(); i += 2)
+		for (int i = 0; i < primeexp.size(); i += 2) {
-			if (primeexp.elementAt(i + 1).intValue() % 2 != 0)
+			if (primeexp.elementAt(i + 1).intValue() % 2 != 0) {
 				resul = resul.multiply(new BigInteger(primeexp.elementAt(i).toString()));
+			}
+		}
 		return resul;
 	} /* Ifactor.core */
 
@@ -690,17 +704,19 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 * @return the moebius function.
 	 */
 	public int moebius() {
-		if (n.compareTo(BigInteger.ONE) <= 0)
+		if (n.compareTo(BigInteger.ONE) <= 0) {
 			return 1;
+		}
 		/* accumulate number of different primes in k */
 		int k = 1;
 		for (int i = 0; i < primeexp.size(); i += 2) {
 			final int e = primeexp.elementAt(i + 1).intValue();
-			if (e > 1)
+			if (e > 1) {
 				return 0;
-			else if (e == 1)
+			} else if (e == 1) {
 				/* accumulates (-1)^k */
 				k *= -1;
+			}
 
 		}
 		return (k);
@@ -714,10 +730,11 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 * @return the larger of the two values.
 	 */
 	public Ifactor max(final Ifactor oth) {
-		if (n.compareTo(oth.n) >= 0)
+		if (n.compareTo(oth.n) >= 0) {
 			return this;
-		else
+		} else {
 			return oth;
+		}
 	} /* Ifactor.max */
 
 	/**
@@ -728,10 +745,11 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 * @return the smaller of the two values.
 	 */
 	public Ifactor min(final Ifactor oth) {
-		if (n.compareTo(oth.n) <= 0)
+		if (n.compareTo(oth.n) <= 0) {
 			return this;
-		else
+		} else {
 			return oth;
+		}
 	} /* Ifactor.min */
 
 	/**
@@ -743,8 +761,9 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 */
 	public static Ifactor max(final Vector<Ifactor> set) {
 		Ifactor resul = set.elementAt(0);
-		for (int i = 1; i < set.size(); i++)
+		for (int i = 1; i < set.size(); i++) {
 			resul = resul.max(set.elementAt(i));
+		}
 		return resul;
 	} /* Ifactor.max */
 
@@ -757,8 +776,9 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 */
 	public static Ifactor min(final Vector<Ifactor> set) {
 		Ifactor resul = set.elementAt(0);
-		for (int i = 1; i < set.size(); i++)
+		for (int i = 1; i < set.size(); i++) {
 			resul = resul.min(set.elementAt(i));
+		}
 		return resul;
 	} /* Ifactor.min */
 
@@ -784,17 +804,19 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	@Override
 	public String toString() {
 		String resul = new String(n.toString() + ":");
-		if (n.compareTo(BigInteger.ONE) == 0)
+		if (n.compareTo(BigInteger.ONE) == 0) {
 			resul += "1";
-		else {
+		} else {
 			boolean firstMul = true;
 			for (int i = 0; i < primeexp.size(); i += 2) {
-				if (!firstMul)
+				if (!firstMul) {
 					resul += "*";
-				if (primeexp.elementAt(i + 1).intValue() > 1)
+				}
+				if (primeexp.elementAt(i + 1).intValue() > 1) {
 					resul += primeexp.elementAt(i).toString() + "^" + primeexp.elementAt(i + 1).toString();
-				else
+				} else {
 					resul += primeexp.elementAt(i).toString();
+				}
 				firstMul = false;
 			}
 		}
@@ -807,7 +829,7 @@ public class Ifactor implements Cloneable, Comparable<Ifactor> {
 	 * java -cp . org.nevec.rjm.Ifactor n<br>
 	 */
 	public static void main(String[] args) throws Exception {
-		BigInteger n = new BigInteger(args[0]);
+		final BigInteger n = new BigInteger(args[0]);
 		System.out.println(new Ifactor(n));
 	} /* Ifactor.main */
 } /* Ifactor */

src/org/nevec/rjm/PartitionsP.java

@@ -63,9 +63,9 @@ public class PartitionsP {
 	private void growto(BigInteger n) {
 		while (a.size() <= n.intValue()) {
 			BigInteger per = new BigInteger("0");
-			BigInteger cursiz = new BigInteger("" + a.size());
+			final BigInteger cursiz = new BigInteger("" + a.size());
 			for (int k = 0; k < a.size(); k++) {
-				BigInteger tmp = a.elementAt(k).multiply(BigIntegerMath.sigma(a.size() - k));
+				final BigInteger tmp = a.elementAt(k).multiply(BigIntegerMath.sigma(a.size() - k));
 				per = per.add(tmp);
 			}
 			a.add(per.divide(cursiz));
@@ -81,8 +81,8 @@ public class PartitionsP {
 	 * @since 2008-10-15
 	 */
 	public static void main(String[] args) throws Exception {
-		PartitionsP a = new PartitionsP();
+		final PartitionsP a = new PartitionsP();
-		int n = (new Integer(args[0])).intValue();
+		final int n = (new Integer(args[0])).intValue();
 		System.out.println("P(" + n + ")=" + a.at(n));
 	}
 }

src/org/nevec/rjm/Prime.java

@@ -86,38 +86,34 @@ public class Prime {
 		/*
 		 * numbers less than 2 are not prime
 		 */
-		if (n.compareTo(two) == -1)
+		if (n.compareTo(two) == -1) {
 			return false;
-		/*
+		} else if (n.compareTo(two) == 0) {
-		 * 2 is prime
-		 */
-		else if (n.compareTo(two) == 0)
 			return true;
-		/*
+		} else if (n.remainder(two).compareTo(BigInteger.ZERO) == 0) {
-		 * even numbers >2 are not prime
-		 */
-		else if (n.remainder(two).compareTo(BigInteger.ZERO) == 0)
 			return false;
-		else {
+		} else {
 			/*
 			 * q= n- 1 = d *2^s with d odd
 			 */
 			final BigInteger q = n.subtract(BigInteger.ONE);
-			int s = q.getLowestSetBit();
+			final int s = q.getLowestSetBit();
-			BigInteger d = q.shiftRight(s);
+			final BigInteger d = q.shiftRight(s);
 
 			/*
 			 * test whether a^d = 1 (mod n)
 			 */
-			if (a.modPow(d, n).compareTo(BigInteger.ONE) == 0)
+			if (a.modPow(d, n).compareTo(BigInteger.ONE) == 0) {
 				return true;
+			}
 
 			/*
 			 * test whether a^(d*2^r) = -1 (mod n), 0<=r<s
 			 */
 			for (int r = 0; r < s; r++) {
-				if (a.modPow(d.shiftLeft(r), n).compareTo(q) == 0)
+				if (a.modPow(d.shiftLeft(r), n).compareTo(q) == 0) {
 					return true;
+				}
 			}
 			return false;
 		}
@@ -140,28 +136,29 @@ public class Prime {
 		final String[] mr = { "2047", "1373653", "25326001", "3215031751", "2152302898747", "3474749660383", "341550071728321" };
 		int mrLim = 0;
 		while (mrLim < mr.length) {
-			int l = n.compareTo(new BigInteger(mr[mrLim]));
+			final int l = n.compareTo(new BigInteger(mr[mrLim]));
-			if (l < 0)
+			if (l < 0) {
 				break;
-			/*
+			} else if (l == 0) {
-			 * if one of the pseudo-primes: this is a composite
-			 */
-			else if (l == 0)
 				return -1;
+			}
 			mrLim++;
 		}
 		/*
 		 * cannot test candidates larger than the last in the mr list
 		 */
-		if (mrLim == mr.length)
+		if (mrLim == mr.length) {
 			return 0;
+		}
 
 		/*
 		 * test the bases prime(1), prime(2) up to prime(mrLim+1)
 		 */
-		for (int p = 0; p <= mrLim; p++)
+		for (int p = 0; p <= mrLim; p++) {
-			if (isSPP(n, at(p)) == false)
+			if (isSPP(n, at(p)) == false) {
 				return -1;
+			}
+		}
 		return 1;
 	}
 
@@ -197,9 +194,11 @@ public class Prime {
 		 */
 		growto(n);
 		BigInteger r = new BigInteger("0");
-		for (int i = 0; i < a.size(); i++)
+		for (int i = 0; i < a.size(); i++) {
-			if (a.elementAt(i).compareTo(n) <= 0)
+			if (a.elementAt(i).compareTo(n) <= 0) {
 				r = r.add(BigInteger.ONE);
+			}
+		}
 		return r;
 	}
 
@@ -213,8 +212,9 @@ public class Prime {
 	 */
 	public BigInteger nextprime(BigInteger n) {
 		/* if n <=1, return 2 */
-		if (n.compareTo(BigInteger.ONE) <= 0)
+		if (n.compareTo(BigInteger.ONE) <= 0) {
 			return (a.elementAt(0));
+		}
 
 		/*
 		 * If the currently largest element in the list is too small, increase
@@ -224,9 +224,11 @@ public class Prime {
 		while (a.lastElement().compareTo(n) <= 0) {
 			growto(nMax.add(new BigInteger("" + 5)));
 		}
-		for (int i = 0; i < a.size(); i++)
+		for (int i = 0; i < a.size(); i++) {
-			if (a.elementAt(i).compareTo(n) == 1)
+			if (a.elementAt(i).compareTo(n) == 1) {
 				return (a.elementAt(i));
+			}
+		}
 		return (a.lastElement());
 	}
 
@@ -240,20 +242,24 @@ public class Prime {
 	 */
 	public BigInteger prevprime(BigInteger n) {
 		/* if n <=2, return 0 */
-		if (n.compareTo(BigInteger.ONE) <= 0)
+		if (n.compareTo(BigInteger.ONE) <= 0) {
 			return BigInteger.ZERO;
+		}
 
 		/*
 		 * If the currently largest element in the list is too small, increase
 		 * in intervals
 		 * of 5 until the list has at least i elements.
 		 */
-		while (a.lastElement().compareTo(n) < 0)
+		while (a.lastElement().compareTo(n) < 0) {
 			growto(nMax.add(new BigInteger("" + 5)));
+		}
 
-		for (int i = 0; i < a.size(); i++)
+		for (int i = 0; i < a.size(); i++) {
-			if (a.elementAt(i).compareTo(n) >= 0)
+			if (a.elementAt(i).compareTo(n) >= 0) {
 				return (a.elementAt(i - 1));
+			}
+		}
 		return (a.lastElement());
 	}
 
@@ -272,8 +278,9 @@ public class Prime {
 				/*
 				 * Test the list of known primes only up to sqrt(n)
 				 */
-				if (a.get(p).multiply(a.get(p)).compareTo(nMax) == 1)
+				if (a.get(p).multiply(a.get(p)).compareTo(nMax) == 1) {
 					break;
+				}
 
 				/*
 				 * The next case means that the p'th number in the list of known
@@ -285,8 +292,9 @@ public class Prime {
 					break;
 				}
 			}
-			if (isp)
+			if (isp) {
 				a.add(nMax);
+			}
 		}
 	}
 
@@ -299,11 +307,12 @@ public class Prime {
 	 * @since 2006-08-14
 	 */
 	public static void main(String[] args) throws Exception {
-		Prime a = new Prime();
+		final Prime a = new Prime();
-		int n = (new Integer(args[0])).intValue();
+		final int n = (new Integer(args[0])).intValue();
 		if (n >= 1) {
-			if (n >= 2)
+			if (n >= 2) {
 				System.out.println("prime(" + (n - 1) + ") = " + a.at(n - 1));
+			}
 			System.out.println("prime(" + n + ") = " + a.at(n));
 			System.out.println("prime(" + (n + 1) + ") = " + a.at(n + 1));
 			System.out.println("pi(" + n + ") = " + a.pi(new BigInteger("" + n)));

src/org/nevec/rjm/RatPoly.java

@@ -43,8 +43,9 @@ class RatPoly {
 	 */
 	public RatPoly(final Vector<Rational> L) {
 		a = new Vector<>();
-		for (int i = 0; i < L.size(); i++)
+		for (int i = 0; i < L.size(); i++) {
 			a.add(L.elementAt(i).clone());
+		}
 		simplify();
 	} /* ctor */
 
@@ -56,10 +57,10 @@ class RatPoly {
 	 */
 	public RatPoly(final String L) throws NumberFormatException {
 		a = new Vector<>();
-		Scanner sc = new Scanner(L);
+		final Scanner sc = new Scanner(L);
 		sc.useDelimiter(",");
 		while (sc.hasNext()) {
-			String tok = sc.next();
+			final String tok = sc.next();
 			a.add(new Rational(tok));
 		}
 		simplify();
@@ -103,16 +104,18 @@ class RatPoly {
 		BigInteger Nmax = BigInteger.ONE.negate();
 		for (int j = 0; j < A.size(); j++) {
 			if (A.elementAt(j).compareTo(BigInteger.ZERO) <= 0) {
-				if (Nmax.compareTo(BigInteger.ZERO) < 0)
+				if (Nmax.compareTo(BigInteger.ZERO) < 0) {
 					Nmax = A.elementAt(j).negate();
-				else
+				} else {
 					Nmax = Nmax.min(A.elementAt(j).negate());
+				}
 			}
 		}
-		if (Nmax.compareTo(BigInteger.ZERO) < 0)
+		if (Nmax.compareTo(BigInteger.ZERO) < 0) {
 			throw new ArithmeticException("Infinite Number of Terms in Series " + Nmax.toString());
+		}
 
-		int nmax = Nmax.intValue() - 1;
+		final int nmax = Nmax.intValue() - 1;
 		init(A, B, nmax);
 	} /* ctor */
 
@@ -130,15 +133,15 @@ class RatPoly {
 	 */
 	protected void init(final Vector<BigInteger> A, final Vector<BigInteger> B, int nmax) throws Error {
 		a = new Vector<>();
-		Factorial f = new Factorial();
+		final Factorial f = new Factorial();
 		for (int n = 0; n <= nmax; n++) {
 			Rational c = new Rational(1, 1);
 			for (int j = 0; j < A.size(); j++) {
-				Rational aEl = new Rational(A.elementAt(j));
+				final Rational aEl = new Rational(A.elementAt(j));
 				c = c.multiply(aEl.Pochhammer(n));
 			}
 			for (int j = 0; j < B.size(); j++) {
-				Rational bEl = new Rational(B.elementAt(j));
+				final Rational bEl = new Rational(B.elementAt(j));
 				c = c.divide(bEl.Pochhammer(n));
 			}
 			c = c.divide(f.at(n));
@@ -155,7 +158,7 @@ class RatPoly {
 	@Override
 	@SuppressWarnings("unchecked")
 	public RatPoly clone() {
-		RatPoly clo = new RatPoly();
+		final RatPoly clo = new RatPoly();
 		clo.a = (Vector<Rational>) a.clone();
 		return clo;
 	} /* clone */
@@ -169,10 +172,11 @@ class RatPoly {
 	 * @return the polynomial coefficient in front of x^n.
 	 */
 	public Rational at(final int n) {
-		if (n < a.size())
+		if (n < a.size()) {
 			return (a.elementAt(n));
-		else
+		} else {
 			return (new Rational(0, 1));
+		}
 	} /* at */
 
 	/**
@@ -187,8 +191,9 @@ class RatPoly {
 	public BigComplex valueOf(BigComplex x, MathContext mc) {
 		/* result is initialized to zero */
 		BigComplex f = new BigComplex();
-		for (int i = degree(); i >= 0; i--)
+		for (int i = degree(); i >= 0; i--) {
 			f = f.multiply(x, mc).add(a.elementAt(i).BigDecimalValue(mc));
+		}
 		return f;
 	} /* valueOf */
 
@@ -202,8 +207,9 @@ class RatPoly {
 	public Rational valueOf(Rational x) {
 		/* result is initialized to zero */
 		Rational f = new Rational(0, 1);
-		for (int i = degree(); i >= 0; i--)
+		for (int i = degree(); i >= 0; i--) {
 			f = f.multiply(x).add(a.elementAt(i));
+		}
 		return f;
 	} /* valueOf */
 
@@ -240,14 +246,15 @@ class RatPoly {
 	 * @param value the new value of the coefficient.
 	 */
 	public void set(final int n, final Rational value) {
-		if (n < a.size())
+		if (n < a.size()) {
 			a.set(n, value);
-		else {
+		} else {
 			/*
 			 * fill intermediate powers with coefficients of zero
 			 */
-			while (a.size() < n)
+			while (a.size() < n) {
 				a.add(new Rational(0, 1));
+			}
 			a.add(value);
 		}
 	} /* set */
@@ -265,7 +272,7 @@ class RatPoly {
 	 *            the new value of the coefficient.
 	 */
 	public void set(final int n, final BigInteger value) {
-		Rational val2 = new Rational(value, BigInteger.ONE);
+		final Rational val2 = new Rational(value, BigInteger.ONE);
 		set(n, val2);
 	} /* set */
 
@@ -282,7 +289,7 @@ class RatPoly {
 	 *            the new value of the coefficient.
 	 */
 	public void set(final int n, final int value) {
-		Rational val2 = new Rational(value, 1);
+		final Rational val2 = new Rational(value, 1);
 		set(n, val2);
 	} /* set */
 
@@ -293,9 +300,10 @@ class RatPoly {
 	 */
 	public void setExp(final int nmax) {
 		a.clear();
-		Factorial factorial = new Factorial();
+		final Factorial factorial = new Factorial();
-		for (int n = 0; n <= nmax; n++)
+		for (int n = 0; n <= nmax; n++) {
 			set(n, new Rational(BigInteger.ONE, factorial.at(n)));
+		}
 	} /* setExp */
 
 	/**
@@ -336,9 +344,11 @@ class RatPoly {
 	 * @since 2010-08-27
 	 */
 	public int ldegree() {
-		for (int n = 0; n < a.size(); n++)
+		for (int n = 0; n < a.size(); n++) {
-			if (a.elementAt(n).compareTo(BigInteger.ZERO) != 0)
+			if (a.elementAt(n).compareTo(BigInteger.ZERO) != 0) {
 				return n;
+			}
+		}
 		return 0;
 	} /* ldegree */
 
@@ -352,10 +362,12 @@ class RatPoly {
 	 *         factor.
 	 */
 	public RatPoly multiply(final Rational val) {
-		RatPoly resul = new RatPoly();
+		final RatPoly resul = new RatPoly();
-		if (val.compareTo(BigInteger.ZERO) != 0)
+		if (val.compareTo(BigInteger.ZERO) != 0) {
-			for (int n = 0; n < a.size(); n++)
+			for (int n = 0; n < a.size(); n++) {
 				resul.set(n, a.elementAt(n).multiply(val));
+			}
+		}
 		return resul;
 	} /* multiply */
 
@@ -370,10 +382,12 @@ class RatPoly {
 	 * @since 2010-08-27
 	 */
 	public RatPoly multiply(final BigInteger val) {
-		RatPoly resul = new RatPoly();
+		final RatPoly resul = new RatPoly();
-		if (val.compareTo(BigInteger.ZERO) != 0)
+		if (val.compareTo(BigInteger.ZERO) != 0) {
-			for (int n = 0; n < a.size(); n++)
+			for (int n = 0; n < a.size(); n++) {
 				resul.set(n, a.elementAt(n).multiply(val));
+			}
+		}
 		return resul;
 	} /* multiply */
 
@@ -385,7 +399,7 @@ class RatPoly {
 	 * @return the product of this with the other polynomial
 	 */
 	public RatPoly multiply(final RatPoly val) {
-		RatPoly resul = new RatPoly();
+		final RatPoly resul = new RatPoly();
 		/*
 		 * the degree of the result is the sum of the two degrees.
 		 */
@@ -410,15 +424,16 @@ class RatPoly {
 	 */
 	public RatPoly pow(final int n) throws ArithmeticException {
 		RatPoly resul = new RatPoly("1");
-		if (n < 0)
+		if (n < 0) {
 			throw new ArithmeticException("negative polynomial power " + n);
-		else {
+		} else {
 			/*
 			 * this ought probably be done with some binary representation
 			 * of the power and a smaller number of multiplications.
 			 */
-			for (int i = 1; i <= n; i++)
+			for (int i = 1; i <= n; i++) {
 				resul = resul.multiply(this);
+			}
 			resul.simplify();
 			return resul;
 		}
@@ -447,7 +462,7 @@ class RatPoly {
 		 * scale the polynomial by division through the expansion coefficient of
 		 * the absolute term
 		 */
-		RatPoly red = divide(a.elementAt(0));
+		final RatPoly red = divide(a.elementAt(0));
 
 		/*
 		 * and remove the leading term (now equal to 1)
@@ -477,14 +492,14 @@ class RatPoly {
 	 * @since 2008-10-25
 	 */
 	public RatPoly add(final RatPoly val) {
-		RatPoly resul = new RatPoly();
+		final RatPoly resul = new RatPoly();
 		/*
 		 * the degree of the result is the larger of the two degrees (before
 		 * simplify() at least).
 		 */
 		final int nmax = (degree() > val.degree()) ? degree() : val.degree();
 		for (int n = 0; n <= nmax; n++) {
-			Rational coef = at(n).add(val.at(n));
+			final Rational coef = at(n).add(val.at(n));
 			resul.set(n, coef);
 		}
 		resul.simplify();
@@ -500,14 +515,14 @@ class RatPoly {
 	 * @since 2008-10-25
 	 */
 	public RatPoly subtract(final RatPoly val) {
-		RatPoly resul = new RatPoly();
+		final RatPoly resul = new RatPoly();
 		/*
 		 * the degree of the result is the larger of the two degrees (before
 		 * simplify() at least).
 		 */
 		final int nmax = (degree() > val.degree()) ? degree() : val.degree();
 		for (int n = 0; n <= nmax; n++) {
-			Rational coef = at(n).subtract(val.at(n));
+			final Rational coef = at(n).subtract(val.at(n));
 			resul.set(n, coef);
 		}
 		resul.simplify();
@@ -525,12 +540,14 @@ class RatPoly {
 	 */
 	public RatPoly divide(final Rational val) throws Error {
 		if (val.compareTo(Rational.ZERO) != 0) {
-			RatPoly resul = new RatPoly();
+			final RatPoly resul = new RatPoly();
-			for (int n = 0; n < a.size(); n++)
+			for (int n = 0; n < a.size(); n++) {
 				resul.set(n, a.elementAt(n).divide(val));
+			}
 			return resul;
-		} else
+		} else {
 			throw new ArithmeticException("Cannot divide " + toPString() + " through zero.");
+		}
 	} /* divide */
 
 	/**
@@ -544,8 +561,8 @@ class RatPoly {
 	 * @throws Error
 	 */
 	public RatPoly divide(final RatPoly val, int nmax) throws Error {
-		RatPoly num = this;
+		final RatPoly num = this;
-		RatPoly denom = val;
+		final RatPoly denom = val;
 
 		/*
 		 * divide by a common smallest power/degree
@@ -553,11 +570,12 @@ class RatPoly {
 		while (num.at(0).compareTo(BigInteger.ZERO) == 0 && denom.at(0).compareTo(BigInteger.ZERO) == 0) {
 			num.a.remove(0);
 			denom.a.remove(0);
-			if (num.size() <= 1 || denom.size() <= 1)
+			if (num.size() <= 1 || denom.size() <= 1) {
 				break;
+			}
 		}
 
-		RatPoly resul = new RatPoly();
+		final RatPoly resul = new RatPoly();
 		/*
 		 * todo: If the polynomial division is exact, we could leave
 		 * the loop earlier, indeed
@@ -587,20 +605,21 @@ class RatPoly {
 	 * @since 2012-03-01
 	 */
 	public RatPoly[] divideAndRemainder(final RatPoly val) throws Error {
-		RatPoly[] ret = new RatPoly[2];
+		final RatPoly[] ret = new RatPoly[2];
 		/*
 		 * remove any high-order zeros
 		 */
-		RatPoly valSimpl = val.clone();
+		final RatPoly valSimpl = val.clone();
 		valSimpl.simplify();
-		RatPoly thisSimpl = clone();
+		final RatPoly thisSimpl = clone();
 		thisSimpl.simplify();
 
 		/*
 		 * catch the case with val equal to zero
 		 */
-		if (valSimpl.degree() == 0 && valSimpl.a.firstElement().compareTo(Rational.ZERO) == 0)
+		if (valSimpl.degree() == 0 && valSimpl.a.firstElement().compareTo(Rational.ZERO) == 0) {
 			throw new ArithmeticException("Division through zero polynomial");
+		}
 		/*
 		 * degree of this smaller than degree of val: remainder is this
 		 */
@@ -628,10 +647,10 @@ class RatPoly {
 			/*
 			 * any remainder left ?
 			 */
-			if (ret[1].degree() < valSimpl.degree())
+			if (ret[1].degree() < valSimpl.degree()) {
 				;
-			else {
+			} else {
-				RatPoly rem[] = ret[1].divideAndRemainder(val);
+				final RatPoly rem[] = ret[1].divideAndRemainder(val);
 				ret[0] = ret[0].add(rem[0]);
 				ret[1] = rem[1];
 			}
@@ -651,16 +670,18 @@ class RatPoly {
 	public String toString() {
 		String str = new String();
 		for (int n = 0; n < a.size(); n++) {
-			if (n == 0)
+			if (n == 0) {
 				str += a.elementAt(n).toString();
-			else
+			} else {
 				str += "," + a.elementAt(n).toString();
+			}
 		}
 		/*
 		 * print at least a sole zero
 		 */
-		if (str.length() == 0)
+		if (str.length() == 0) {
 			str = "0";
+		}
 		return str;
 	} /* toString */
 
@@ -677,21 +698,24 @@ class RatPoly {
 			final BigInteger num = a.elementAt(n).a;
 			if (num.compareTo(BigInteger.ZERO) != 0) {
 				str += " ";
-				if (num.compareTo(BigInteger.ZERO) > 0)
+				if (num.compareTo(BigInteger.ZERO) > 0) {
 					str += "+";
+				}
 				str += a.elementAt(n).toString();
 				if (n > 0) {
 					str += "*x";
-					if (n > 1)
+					if (n > 1) {
 						str += "^" + n;
+					}
 				}
 			}
 		}
 		/*
 		 * print at least a sole zero
 		 */
-		if (str.length() == 0)
+		if (str.length() == 0) {
 			str = "0";
+		}
 		return str;
 	} /* toPString */
 
@@ -703,12 +727,14 @@ class RatPoly {
 	 */
 	private void simplify() {
 		int n = a.size() - 1;
-		if (n >= 0)
+		if (n >= 0) {
 			while (a.elementAt(n).compareTo(BigInteger.ZERO) == 0) {
 				a.remove(n);
-				if (--n < 0)
+				if (--n < 0) {
 					break;
+				}
 			}
+		}
 	} /* simplify */
 
 	/**
@@ -718,13 +744,13 @@ class RatPoly {
 	 * @since 2008-10-26
 	 */
 	public RatPoly derive() {
-		if (a.size() <= 1)
+		if (a.size() <= 1) {
 			/*
 			 * derivative of the constant is just zero
 			 */
 			return new RatPoly();
-		else {
+		} else {
-			RatPoly d = new RatPoly();
+			final RatPoly d = new RatPoly();
 			for (int i = 1; i <= degree(); i++) {
 				final Rational c = a.elementAt(i).multiply(i);
 				d.set(i - 1, c);
@@ -742,7 +768,7 @@ class RatPoly {
 	 * @since 2008-10-26
 	 */
 	public RatPoly monic() throws Error {
-		RatPoly m = new RatPoly();
+		final RatPoly m = new RatPoly();
 		final int d = degree();
 		for (int i = 0; i <= d; i++) {
 			final Rational c = a.elementAt(i).divide(a.elementAt(d));
@@ -764,7 +790,7 @@ class RatPoly {
 		/*
 		 * Start with the polynomial 0
 		 */
-		RatPoly r = new RatPoly();
+		final RatPoly r = new RatPoly();
 		for (int i = 1; i <= maxdeg; i++) {
 			Rational c = new Rational();
 			for (int d = 1; d <= i && d < a.size(); d++) {
@@ -792,12 +818,13 @@ class RatPoly {
 		/*
 		 * Start with the polynomial 0
 		 */
-		RatPoly r = new RatPoly();
+		final RatPoly r = new RatPoly();
 		for (int i = 1; i <= maxdeg; i++) {
 			Rational c = new Rational();
 			for (int d = 1; d <= i && d < a.size(); d++) {
-				if (i % d == 0)
+				if (i % d == 0) {
 					c = c.add(a.elementAt(d));
+				}
 			}
 			r.set(i, c);
 		}
@@ -815,11 +842,12 @@ class RatPoly {
 	 * @since 2008-10-26
 	 */
 	public RatPoly binomialT(int maxdeg) {
-		RatPoly r = new RatPoly();
+		final RatPoly r = new RatPoly();
 		for (int i = 0; i <= maxdeg; i++) {
 			Rational c = new Rational(0, 1);
-			for (int j = 0; j <= i && j < a.size(); j++)
+			for (int j = 0; j <= i && j < a.size(); j++) {
 				c = c.add(a.elementAt(j).multiply(BigIntegerMath.binomial(i, j)));
+			}
 			r.set(i, c);
 		}
 		r.simplify();
@@ -836,14 +864,16 @@ class RatPoly {
 	 * @since 2008-10-26
 	 */
 	public RatPoly binomialTInv(int maxdeg) {
-		RatPoly r = new RatPoly();
+		final RatPoly r = new RatPoly();
 		for (int i = 0; i <= maxdeg; i++) {
 			Rational c = new Rational(0, 1);
-			for (int j = 0; j <= i && j < a.size(); j++)
+			for (int j = 0; j <= i && j < a.size(); j++) {
-				if ((j + i) % 2 != 0)
+				if ((j + i) % 2 != 0) {
 					c = c.subtract(a.elementAt(j).multiply(BigIntegerMath.binomial(i, j)));
-				else
+				} else {
 					c = c.add(a.elementAt(j).multiply(BigIntegerMath.binomial(i, j)));
+				}
+			}
 			r.set(i, c);
 		}
 		r.simplify();
@@ -865,9 +895,10 @@ class RatPoly {
 	 * @since 2008-10-26
 	 */
 	public RatPoly trunc(int newdeg) {
-		RatPoly t = new RatPoly();
+		final RatPoly t = new RatPoly();
-		for (int i = 0; i <= newdeg; i++)
+		for (int i = 0; i <= newdeg; i++) {
 			t.set(i, at(i));
+		}
 		t.simplify();
 		return t;
 	} /* trunc */
@@ -883,10 +914,10 @@ class RatPoly {
 	 * @since 2008-10-26
 	 */
 	public Vector<BigComplex> roots(int digits) throws Error {
-		RatPoly mon = monic();
+		final RatPoly mon = monic();
 
-		Random rand = new Random();
+		final Random rand = new Random();
-		MathContext mc = new MathContext(digits + 3, RoundingMode.DOWN);
+		final MathContext mc = new MathContext(digits + 3, RoundingMode.DOWN);
 
 		Vector<BigComplex> res = new Vector<>();
 
@@ -894,9 +925,10 @@ class RatPoly {
 		double randRad = 0.;
 		for (int i = 0; i <= d; i++) {
 			/* scale coefficient at maximum degree */
-			double absi = Math.abs(mon.at(i).doubleValue());
+			final double absi = Math.abs(mon.at(i).doubleValue());
-			if (absi > randRad)
+			if (absi > randRad) {
 				randRad = absi;
+			}
 		}
 		randRad += 1.0;
 
@@ -904,8 +936,8 @@ class RatPoly {
 		 * initial values randomly in radius 1+randRad
 		 */
 		for (int i = 0; i < d; i++) {
-			double rad = randRad * rand.nextDouble();
+			final double rad = randRad * rand.nextDouble();
-			double phi = 2.0 * 3.14159 * rand.nextDouble();
+			final double phi = 2.0 * 3.14159 * rand.nextDouble();
 			res.add(i, new BigComplex(rad * Math.cos(phi), rad * Math.sin(phi)));
 		}
 
@@ -918,7 +950,7 @@ class RatPoly {
 		for (; !convr;)// ORIGINAL LINE: for(int itr =0 ; ! convr ; itr++)
 		{
 			convr = true;
-			Vector<BigComplex> resPlus = new Vector<>();
+			final Vector<BigComplex> resPlus = new Vector<>();
 			for (int v = 0; v < d; v++) {
 				/*
 				 * evaluate f(x)/(x-root1)/(x-root2)/... (x-rootdegr), Newton
@@ -927,19 +959,22 @@ class RatPoly {
 				BigComplex thisx = res.elementAt(v);
 				BigComplex nv = mon.valueOf(thisx, mc);
 				for (int j = 0; j < d; j++) {
-					if (j != v)
+					if (j != v) {
 						nv = nv.divide(thisx.subtract(res.elementAt(j)), mc);
+					}
 				}
 
 				/* is this value converged ? */
-				if (nv.abs(mc).doubleValue() > thisx.abs(mc).doubleValue() * Math.pow(10.0, -digits))
+				if (nv.abs(mc).doubleValue() > thisx.abs(mc).doubleValue() * Math.pow(10.0, -digits)) {
 					convr = false;
+				}
 
 				thisx = thisx.subtract(nv);
 
 				/* If unstable, start over */
-				if (thisx.abs(MathContext.DECIMAL32).doubleValue() > randRad)
+				if (thisx.abs(MathContext.DECIMAL32).doubleValue() > randRad) {
 					return roots(digits);
+				}
 
 				resPlus.add(thisx);
 			}
@@ -959,9 +994,9 @@ class RatPoly {
 	 */
 	public Vector<BigInteger> iroots() {
 		/* The vector of the roots */
-		Vector<BigInteger> res = new Vector<>();
+		final Vector<BigInteger> res = new Vector<>();
 
-		int lowd = ldegree();
+		final int lowd = ldegree();
 		if (lowd == 0 && a.elementAt(0).compareTo(BigInteger.ZERO) == 0) {
 			/*
 			 * Case of polynomial identical to zero:
@@ -977,28 +1012,29 @@ class RatPoly {
 		 * start with denominator of first non-zero coefficient.
 		 */
 		BigInteger lcmDeno = a.elementAt(lowd).b;
-		for (int i = lowd + 1; i < degree(); i++)
+		for (int i = lowd + 1; i < degree(); i++) {
 			lcmDeno = BigIntegerMath.lcm(lcmDeno, a.elementAt(i).b);
+		}
 
 		/*
 		 * and eventually get the integer polynomial by ignoring the
 		 * denominators
 		 */
-		Vector<BigInteger> ipo = new Vector<>();
+		final Vector<BigInteger> ipo = new Vector<>();
 		for (int i = 0; i < a.size(); i++) {
-			BigInteger d = a.elementAt(i).a.multiply(lcmDeno).divide(a.elementAt(i).b);
+			final BigInteger d = a.elementAt(i).a.multiply(lcmDeno).divide(a.elementAt(i).b);
 			ipo.add(d);
 		}
 
-		BigIntegerPoly p = new BigIntegerPoly(ipo);
+		final BigIntegerPoly p = new BigIntegerPoly(ipo);
 		/*
 		 * collect the integer roots (multiple roots only once). Since we
 		 * removed the zero already above, cand does not contain zeros.
 		 */
-		Vector<BigInteger> cand = p.iroots();
+		final Vector<BigInteger> cand = p.iroots();
 		for (int i = 0; i < cand.size(); i++) {
 			final BigInteger r = cand.elementAt(i);
-			int deg = p.rootDeg(r);
+			final int deg = p.rootDeg(r);
 			res.add(r);
 			res.add(new BigInteger("" + deg));
 		}

src/org/nevec/rjm/Rational.java

@@ -133,7 +133,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 *            does not yet test for a denominator equal to zero
 	 */
 	public Rational(String str, int radix) {
-		int hasslah = str.indexOf("/");
+		final int hasslah = str.indexOf("/");
 		if (hasslah == -1) {
 			a = new BigInteger(str, radix);
 			b = new BigInteger("1", radix);
@@ -159,8 +159,8 @@ public class Rational implements Cloneable, Comparable<Rational> {
 		 * protected access means this does not work return new
 		 * Rational(a.clone(), b.clone()) ;
 		 */
-		BigInteger aclon = new BigInteger("" + a);
+		final BigInteger aclon = new BigInteger("" + a);
-		BigInteger bclon = new BigInteger("" + b);
+		final BigInteger bclon = new BigInteger("" + b);
 		return new Rational(aclon, bclon);
 	} /* Rational.clone */
 
@@ -172,8 +172,8 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return the product of this with the val.
 	 */
 	public Rational multiply(final Rational val) {
-		BigInteger num = a.multiply(val.a);
+		final BigInteger num = a.multiply(val.a);
-		BigInteger deno = b.multiply(val.b);
+		final BigInteger deno = b.multiply(val.b);
 		/*
 		 * Normalization to an coprime format will be done inside the ctor() and
 		 * is not duplicated here.
@@ -189,7 +189,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return the product of this with the value.
 	 */
 	public Rational multiply(final BigInteger val) {
-		Rational val2 = new Rational(val, BigInteger.ONE);
+		final Rational val2 = new Rational(val, BigInteger.ONE);
 		return (multiply(val2));
 	} /* Rational.multiply */
 
@@ -201,7 +201,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return the product of this with the value.
 	 */
 	public Rational multiply(final int val) {
-		BigInteger tmp = new BigInteger("" + val);
+		final BigInteger tmp = new BigInteger("" + val);
 		return multiply(tmp);
 	} /* Rational.multiply */
 
@@ -214,15 +214,17 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 *         exponent is 0, the value 1 is returned.
 	 */
 	public Rational pow(int exponent) {
-		if (exponent == 0)
+		if (exponent == 0) {
 			return new Rational(1, 1);
+		}
 
-		BigInteger num = a.pow(Math.abs(exponent));
+		final BigInteger num = a.pow(Math.abs(exponent));
-		BigInteger deno = b.pow(Math.abs(exponent));
+		final BigInteger deno = b.pow(Math.abs(exponent));
-		if (exponent > 0)
+		if (exponent > 0) {
 			return (new Rational(num, deno));
-		else
+		} else {
 			return (new Rational(deno, num));
+		}
 	} /* Rational.pow */
 
 	/**
@@ -237,10 +239,12 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 */
 	public Rational pow(BigInteger exponent) throws Error {
 		/* test for overflow */
-		if (exponent.compareTo(MAX_INT) == 1)
+		if (exponent.compareTo(MAX_INT) == 1) {
 			throw new Error(Errors.NUMBER_TOO_LARGE);
-		if (exponent.compareTo(MIN_INT) == -1)
+		}
+		if (exponent.compareTo(MIN_INT) == -1) {
 			throw new Error(Errors.NUMBER_TOO_SMALL);
+		}
 
 		/* promote to the simpler interface above */
 		return pow(exponent.intValue());
@@ -259,15 +263,18 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 */
 	public Rational root(BigInteger r) throws Error {
 		/* test for overflow */
-		if (r.compareTo(MAX_INT) == 1)
+		if (r.compareTo(MAX_INT) == 1) {
 			throw new Error(Errors.NUMBER_TOO_LARGE);
-		if (r.compareTo(MIN_INT) == -1)
+		}
+		if (r.compareTo(MIN_INT) == -1) {
 			throw new Error(Errors.NUMBER_TOO_SMALL);
+		}
 
-		int rthroot = r.intValue();
+		final int rthroot = r.intValue();
 		/* cannot pull root of a negative value with even-valued root */
-		if (compareTo(ZERO) == -1 && (rthroot % 2) == 0)
+		if (compareTo(ZERO) == -1 && (rthroot % 2) == 0) {
 			throw new Error(Errors.NEGATIVE_PARAMETER);
+		}
 
 		/*
 		 * extract a sign such that we calculate |n|^(1/r), still r carrying any
@@ -278,13 +285,14 @@ public class Rational implements Cloneable, Comparable<Rational> {
 		/*
 		 * delegate the main work to ifactor#root()
 		 */
-		Ifactor num = new Ifactor(a.abs());
+		final Ifactor num = new Ifactor(a.abs());
-		Ifactor deno = new Ifactor(b);
+		final Ifactor deno = new Ifactor(b);
 		final Rational resul = num.root(rthroot).divide(deno.root(rthroot));
-		if (flipsign)
+		if (flipsign) {
 			return resul.negate();
-		else
+		} else {
 			return resul;
+		}
 	} /* Rational.root */
 
 	/**
@@ -298,14 +306,15 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2009-05-18
 	 */
 	public Rational pow(Rational exponent) throws Error {
-		if (exponent.a.compareTo(BigInteger.ZERO) == 0)
+		if (exponent.a.compareTo(BigInteger.ZERO) == 0) {
 			return new Rational(1, 1);
+		}
 
 		/*
 		 * calculate (a/b)^(exponent.a/exponent.b) as
 		 * ((a/b)^exponent.a)^(1/exponent.b) = tmp^(1/exponent.b)
 		 */
-		Rational tmp = pow(exponent.a);
+		final Rational tmp = pow(exponent.a);
 		return tmp.root(exponent.b);
 	} /* Rational.pow */
 
@@ -318,10 +327,11 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @throws Error
 	 */
 	public Rational divide(final Rational val) throws Error {
-		if (val.compareTo(Rational.ZERO) == 0)
+		if (val.compareTo(Rational.ZERO) == 0) {
 			throw new Error(Errors.DIVISION_BY_ZERO);
-		BigInteger num = a.multiply(val.b);
+		}
-		BigInteger deno = b.multiply(val.a);
+		final BigInteger num = a.multiply(val.b);
+		final BigInteger deno = b.multiply(val.a);
 		/*
 		 * Reduction to a coprime format is done inside the ctor, and not
 		 * repeated here.
@@ -338,9 +348,10 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @throws Error
 	 */
 	public Rational divide(BigInteger val) throws Error {
-		if (val.compareTo(BigInteger.ZERO) == 0)
+		if (val.compareTo(BigInteger.ZERO) == 0) {
 			throw new Error(Errors.DIVISION_BY_ZERO);
-		Rational val2 = new Rational(val, BigInteger.ONE);
+		}
+		final Rational val2 = new Rational(val, BigInteger.ONE);
 		return (divide(val2));
 	} /* Rational.divide */
 
@@ -353,9 +364,10 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @throws Error
 	 */
 	public Rational divide(int val) throws Error {
-		if (val == 0)
+		if (val == 0) {
 			throw new Error(Errors.DIVISION_BY_ZERO);
-		Rational val2 = new Rational(val, 1);
+		}
+		final Rational val2 = new Rational(val, 1);
 		return (divide(val2));
 	} /* Rational.divide */
 
@@ -367,8 +379,8 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return this+val.
 	 */
 	public Rational add(Rational val) {
-		BigInteger num = a.multiply(val.b).add(b.multiply(val.a));
+		final BigInteger num = a.multiply(val.b).add(b.multiply(val.a));
-		BigInteger deno = b.multiply(val.b);
+		final BigInteger deno = b.multiply(val.b);
 		return (new Rational(num, deno));
 	} /* Rational.add */
 
@@ -380,7 +392,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return this+val.
 	 */
 	public Rational add(BigInteger val) {
-		Rational val2 = new Rational(val, BigInteger.ONE);
+		final Rational val2 = new Rational(val, BigInteger.ONE);
 		return (add(val2));
 	} /* Rational.add */
 
@@ -393,7 +405,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since May 26 2010
 	 */
 	public Rational add(int val) {
-		BigInteger val2 = a.add(b.multiply(new BigInteger("" + val)));
+		final BigInteger val2 = a.add(b.multiply(new BigInteger("" + val)));
 		return new Rational(val2, b);
 	} /* Rational.add */
 
@@ -414,7 +426,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return this - val.
 	 */
 	public Rational subtract(Rational val) {
-		Rational val2 = val.negate();
+		final Rational val2 = val.negate();
 		return (add(val2));
 	} /* Rational.subtract */
 
@@ -426,7 +438,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return this - val.
 	 */
 	public Rational subtract(BigInteger val) {
-		Rational val2 = new Rational(val, BigInteger.ONE);
+		final Rational val2 = new Rational(val, BigInteger.ONE);
 		return (subtract(val2));
 	} /* Rational.subtract */
 
@@ -438,7 +450,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @return this - val.
 	 */
 	public Rational subtract(int val) {
-		Rational val2 = new Rational(val, 1);
+		final Rational val2 = new Rational(val, 1);
 		return (subtract(val2));
 	} /* Rational.subtract */
 
@@ -455,8 +467,9 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @throws Error
 	 */
 	public static Rational binomial(Rational n, BigInteger m) throws Error {
-		if (m.compareTo(BigInteger.ZERO) == 0)
+		if (m.compareTo(BigInteger.ZERO) == 0) {
 			return Rational.ONE;
+		}
 		Rational bin = n;
 		for (BigInteger i = new BigInteger("2"); i.compareTo(m) != 1; i = i.add(BigInteger.ONE)) {
 			bin = bin.multiply(n.subtract(i.subtract(BigInteger.ONE))).divide(i);
@@ -477,8 +490,9 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @throws Error
 	 */
 	public static Rational binomial(Rational n, int m) throws Error {
-		if (m == 0)
+		if (m == 0) {
 			return Rational.ONE;
+		}
 		Rational bin = n;
 		for (int i = 2; i <= m; i++) {
 			bin = bin.multiply(n.subtract(i - 1)).divide(i);
@@ -499,13 +513,14 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @throws Error
 	 */
 	public static Rational hankelSymb(Rational n, int k) throws Error {
-		if (k == 0)
+		if (k == 0) {
 			return Rational.ONE;
-		else if (k < 0)
+		} else if (k < 0) {
 			throw new Error(Errors.NEGATIVE_PARAMETER);
+		}
 		Rational nkhalf = n.subtract(k).add(Rational.HALF);
 		nkhalf = nkhalf.Pochhammer(2 * k);
-		Factorial f = new Factorial();
+		final Factorial f = new Factorial();
 		return nkhalf.divide(f.at(k));
 	} /* Rational.binomial */
 
@@ -545,12 +560,13 @@ public class Rational implements Cloneable, Comparable<Rational> {
 		/*
 		 * is already integer: return the numerator
 		 */
-		if (b.compareTo(BigInteger.ONE) == 0)
+		if (b.compareTo(BigInteger.ONE) == 0) {
 			return a;
-		else if (a.compareTo(BigInteger.ZERO) > 0)
+		} else if (a.compareTo(BigInteger.ZERO) > 0) {
 			return a.divide(b);
-		else
+		} else {
 			return a.divide(b).subtract(BigInteger.ONE);
+		}
 	} /* Rational.floor */
 
 	/**
@@ -563,12 +579,13 @@ public class Rational implements Cloneable, Comparable<Rational> {
 		/*
 		 * is already integer: return the numerator
 		 */
-		if (b.compareTo(BigInteger.ONE) == 0)
+		if (b.compareTo(BigInteger.ONE) == 0) {
 			return a;
-		else if (a.compareTo(BigInteger.ZERO) > 0)
+		} else if (a.compareTo(BigInteger.ZERO) > 0) {
 			return a.divide(b).add(BigInteger.ONE);
-		else
+		} else {
 			return a.divide(b);
+		}
 	} /* Rational.ceil */
 
 	/**
@@ -580,10 +597,11 @@ public class Rational implements Cloneable, Comparable<Rational> {
 		/*
 		 * is already integer: return the numerator
 		 */
-		if (b.compareTo(BigInteger.ONE) == 0)
+		if (b.compareTo(BigInteger.ONE) == 0) {
 			return a;
-		else
+		} else {
 			return a.divide(b);
+		}
 	} /* Rational.trunc */
 
 	/**
@@ -626,10 +644,11 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 */
 	@Override
 	public String toString() {
-		if (b.compareTo(BigInteger.ONE) != 0)
+		if (b.compareTo(BigInteger.ONE) != 0) {
 			return (a.toString() + "/" + b.toString());
-		else
+		} else {
 			return a.toString();
+		}
 	} /* Rational.toString */
 
 	/**
@@ -644,7 +663,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 		 * separate invocation a.doubleValue() or b.doubleValue(), we divide
 		 * first in a BigDecimal environment and convert the result.
 		 */
-		BigDecimal adivb = (new BigDecimal(a)).divide(new BigDecimal(b), MathContext.DECIMAL128);
+		final BigDecimal adivb = (new BigDecimal(a)).divide(new BigDecimal(b), MathContext.DECIMAL128);
 		return adivb.doubleValue();
 	} /* Rational.doubleValue */
 
@@ -655,7 +674,7 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2009-08-06
 	 */
 	public float floatValue() {
-		BigDecimal adivb = (new BigDecimal(a)).divide(new BigDecimal(b), MathContext.DECIMAL128);
+		final BigDecimal adivb = (new BigDecimal(a)).divide(new BigDecimal(b), MathContext.DECIMAL128);
 		return adivb.floatValue();
 	} /* Rational.floatValue */
 
@@ -672,8 +691,8 @@ public class Rational implements Cloneable, Comparable<Rational> {
 		/*
 		 * numerator and denominator individually rephrased
 		 */
-		BigDecimal n = new BigDecimal(a);
+		final BigDecimal n = new BigDecimal(a);
-		BigDecimal d = new BigDecimal(b);
+		final BigDecimal d = new BigDecimal(b);
 		/*
 		 * the problem with n.divide(d,mc) is that the apparent precision might
 		 * be smaller than what is set by mc if the value has a precise
@@ -692,11 +711,12 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 */
 	public String toFString(int digits) {
 		if (b.compareTo(BigInteger.ONE) != 0) {
-			MathContext mc = new MathContext(digits, RoundingMode.DOWN);
+			final MathContext mc = new MathContext(digits, RoundingMode.DOWN);
-			BigDecimal f = (new BigDecimal(a)).divide(new BigDecimal(b), mc);
+			final BigDecimal f = (new BigDecimal(a)).divide(new BigDecimal(b), mc);
 			return (f.toString());
-		} else
+		} else {
 			return a.toString();
+		}
 	} /* Rational.toFString */
 
 	/**
@@ -708,10 +728,11 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2008-10-19
 	 */
 	public Rational max(final Rational val) {
-		if (compareTo(val) > 0)
+		if (compareTo(val) > 0) {
 			return this;
-		else
+		} else {
 			return val;
+		}
 	} /* Rational.max */
 
 	/**
@@ -723,10 +744,11 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2008-10-19
 	 */
 	public Rational min(final Rational val) {
-		if (compareTo(val) < 0)
+		if (compareTo(val) < 0) {
 			return this;
-		else
+		} else {
 			return val;
+		}
 	} /* Rational.min */
 
 	/**
@@ -738,18 +760,19 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2008-10-25
 	 */
 	public Rational Pochhammer(final BigInteger n) {
-		if (n.compareTo(BigInteger.ZERO) < 0)
+		if (n.compareTo(BigInteger.ZERO) < 0) {
 			return null;
-		else if (n.compareTo(BigInteger.ZERO) == 0)
+		} else if (n.compareTo(BigInteger.ZERO) == 0) {
 			return Rational.ONE;
-		else {
+		} else {
 			/*
 			 * initialize results with the current value
 			 */
 			Rational res = new Rational(a, b);
 			BigInteger i = BigInteger.ONE;
-			for (; i.compareTo(n) < 0; i = i.add(BigInteger.ONE))
+			for (; i.compareTo(n) < 0; i = i.add(BigInteger.ONE)) {
 				res = res.multiply(add(i));
+			}
 			return res;
 		}
 	} /* Rational.pochhammer */
@@ -784,8 +807,9 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2010-05-26
 	 */
 	public boolean isInteger() {
-		if (!isBigInteger())
+		if (!isBigInteger()) {
 			return false;
+		}
 		return (a.compareTo(MAX_INT) <= 0 && a.compareTo(MIN_INT) >= 0);
 	} /* Rational.isInteger */
 
@@ -797,8 +821,9 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2011-02-13
 	 */
 	int intValue() throws Error {
-		if (!isInteger())
+		if (!isInteger()) {
 			throw new Error(Errors.CONVERSION_ERROR);
+		}
 		return a.intValue();
 	}
 
@@ -810,8 +835,9 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 * @since 2012-03-02
 	 */
 	BigInteger BigIntegerValue() throws Error {
-		if (!isBigInteger())
+		if (!isBigInteger()) {
 			throw new Error(Errors.CONVERSION_ERROR);
+		}
 		return a;
 	}
 
@@ -845,8 +871,9 @@ public class Rational implements Cloneable, Comparable<Rational> {
 	 */
 	static public BigInteger lcmDenom(final Rational[] vals) {
 		BigInteger l = BigInteger.ONE;
-		for (int v = 0; v < vals.length; v++)
+		for (final Rational val : vals) {
-			l = BigIntegerMath.lcm(l, vals[v].b);
+			l = BigIntegerMath.lcm(l, val.b);
+		}
 		return l;
 	} /* Rational.lcmDenom */
 

src/org/nevec/rjm/Wigner3j.java

@@ -37,43 +37,45 @@ public class Wigner3j {
 	static public void main(String args[]) throws Error {
 		if (args[0].compareTo("6j") == 0) {
 			try {
-				String m1 = "6";
+				final String m1 = "6";
-				String t1 = "1 2 -3 -1 5 6";
+				final String t1 = "1 2 -3 -1 5 6";
-				String t2 = "4 -5 3 -4 -2 -6";
+				final String t2 = "4 -5 3 -4 -2 -6";
 				String j = "";
-				for (int i = 1; i <= 6; i++)
+				for (int i = 1; i <= 6; i++) {
 					j += args[i] + " ";
-				BigSurdVec w = wigner3j(m1, t1, t2, j);
+				}
+				final BigSurdVec w = wigner3j(m1, t1, t2, j);
 				System.out.println(w.toString());
-			} catch (Exception e) {
+			} catch (final Exception e) {
 				System.out.println(e.getMessage());
 			}
 		} else if (args[0].compareTo("9j") == 0) {
 			try {
-				String m1 = "9";
+				final String m1 = "9";
-				String t1 = "1 3 2 4 6 5 7 9 8";
+				final String t1 = "1 3 2 4 6 5 7 9 8";
-				String t2 = "2 8 5 6 3 9 7 4 1";
+				final String t2 = "2 8 5 6 3 9 7 4 1";
 				String j = "";
-				for (int i = 1; i <= 9; i++)
+				for (int i = 1; i <= 9; i++) {
 					j += args[i] + " ";
-				BigSurdVec w = wigner3j(m1, t1, t2, j);
+				}
+				final BigSurdVec w = wigner3j(m1, t1, t2, j);
 				System.out.println(w.toString());
-			} catch (Exception e) {
+			} catch (final Exception e) {
 				System.out.println(e.getMessage());
 			}
 		} else if (args[0].compareTo("3jm") == 0) {
-			int j1 = (new Integer(args[1])).intValue();
+			final int j1 = (new Integer(args[1])).intValue();
-			int j2 = (new Integer(args[2])).intValue();
+			final int j2 = (new Integer(args[2])).intValue();
-			int j3 = (new Integer(args[3])).intValue();
+			final int j3 = (new Integer(args[3])).intValue();
-			int m1 = (new Integer(args[4])).intValue();
+			final int m1 = (new Integer(args[4])).intValue();
-			int m2 = (new Integer(args[5])).intValue();
+			final int m2 = (new Integer(args[5])).intValue();
-			int m3 = (new Integer(args[6])).intValue();
+			final int m3 = (new Integer(args[6])).intValue();
 			try {
 				BigSurd w = wigner3jm(j1, j2, j3, m1, m2, m3);
 				System.out.println(w.toString());
 				w = w.multiply(new BigSurd(j3 + 1, 1));
 				System.out.println("CG factor sqrt" + (j3 + 1) + "sign " + ((j2 - j2 - m3) / 2) + " " + w.toString());
-			} catch (Exception e) {
+			} catch (final Exception e) {
 				System.out.println(e.getMessage());
 			}
 		} else {
@@ -108,12 +110,12 @@ public class Wigner3j {
 	 * @throws Error
 	 */
 	static public BigSurd wigner3jm(int j1, int j2, int j3, int m1, int m2, int m3) throws Error {
-		Rational J1 = new Rational(j1, 2);
+		final Rational J1 = new Rational(j1, 2);
-		Rational J2 = new Rational(j2, 2);
+		final Rational J2 = new Rational(j2, 2);
-		Rational J3 = new Rational(j3, 2);
+		final Rational J3 = new Rational(j3, 2);
-		Rational M1 = new Rational(m1, 2);
+		final Rational M1 = new Rational(m1, 2);
-		Rational M2 = new Rational(m2, 2);
+		final Rational M2 = new Rational(m2, 2);
-		Rational M3 = new Rational(m3, 2);
+		final Rational M3 = new Rational(m3, 2);
 		return wigner3jm(J1, J2, J3, M1, M2, M3);
 	} /* wigner3jm */
 
@@ -148,7 +150,7 @@ public class Wigner3j {
 		 * The rest of the line is ignored.
 		 */
 		Scanner s = new Scanner(m1);
-		int m = s.nextInt();
+		final int m = s.nextInt();
 		if (m % 3 != 0) {
 			s.close();
 			throw new IllegalArgumentException("Angular momenta " + m + " not a multiple of three.");
@@ -158,8 +160,8 @@ public class Wigner3j {
 		 * Scan the numbers in the line "j". Excess numbers beyond what has been
 		 * announced in the "m" line are ignored.
 		 */
-		int[] jvec = new int[m];
+		final int[] jvec = new int[m];
-		int[] tvec = new int[2 * m];
+		final int[] tvec = new int[2 * m];
 
 		s.close();
 
@@ -183,14 +185,16 @@ public class Wigner3j {
 		 */
 		s = new Scanner(t1);
 		int ti = 0;
-		while (s.hasNextInt())
+		while (s.hasNextInt()) {
 			tvec[ti++] = s.nextInt();
+		}
 
 		s.close();
 
 		s = new Scanner(t2);
-		while (s.hasNextInt())
+		while (s.hasNextInt()) {
 			tvec[ti++] = s.nextInt();
+		}
 
 		/*
 		 * Basic sanity checks. All indices in the first two lines address a
@@ -205,18 +209,19 @@ public class Wigner3j {
 			throw new IllegalArgumentException("triad-count " + ti + " not twice j-count " + ji);
 		}
 
-		int[] jfreq = new int[m];
+		final int[] jfreq = new int[m];
-		for (ji = 0; ji < jfreq.length; ji++)
+		for (ji = 0; ji < jfreq.length; ji++) {
 			jfreq[ji] = 0;
+		}
 
 		/*
 		 * maintain a 0-based index which shows where the j-value has its first
 		 * and second occurrence in the flattened list of triads.
 		 */
-		int[][] jhash = new int[m][2];
+		final int[][] jhash = new int[m][2];
 
 		for (ti = 0; ti < 2 * m; ti++) {
-			int t = tvec[ti];
+			final int t = tvec[ti];
 			if (t == 0 || Math.abs(t) > jvec.length) {
 				s.close();
 				throw new IllegalArgumentException("Triad index " + t + " out of bounds");
@@ -233,7 +238,7 @@ public class Wigner3j {
 		 * Move on from the 2j+1 values of the input to the j-values. Subtract
 		 * one and divide through 2.
 		 */
-		Rational[] J = new Rational[jvec.length];
+		final Rational[] J = new Rational[jvec.length];
 		for (ji = 0; ji < jvec.length; ji++) {
 			J[ji] = new Rational(jvec[ji] - 1, 2);
 		}
@@ -242,14 +247,15 @@ public class Wigner3j {
 		 * Convert the 1-based indices to 0-based indices, loosing the sign
 		 * information.
 		 */
-		int[] triadidx = new int[tvec.length];
+		final int[] triadidx = new int[tvec.length];
-		for (ti = 0; ti < tvec.length; ti++)
+		for (ti = 0; ti < tvec.length; ti++) {
 			triadidx[ti] = Math.abs(tvec[ti]) - 1;
+		}
 
 		/*
 		 * The M-values are all null (undetermined) at the start.
 		 */
-		Rational[] M = new Rational[J.length];
+		final Rational[] M = new Rational[J.length];
 		s.close();
 		return wigner3j(tvec, J, M, triadidx);
 	} /* wigner3j */
@@ -286,10 +292,12 @@ public class Wigner3j {
 		 */
 		for (int t = 0; t < triadidx.length; t += 3) {
 			/* Ensure |J[t]-J[t+1]| <= J[t+2] <= J[t]+J[t+1] */
-			if (J[triadidx[t]].subtract(J[triadidx[t + 1]]).abs().compareTo(J[triadidx[t + 2]]) > 0)
+			if (J[triadidx[t]].subtract(J[triadidx[t + 1]]).abs().compareTo(J[triadidx[t + 2]]) > 0) {
 				return res;
-			if (J[triadidx[t]].add(J[triadidx[t + 1]]).compareTo(J[triadidx[t + 2]]) < 0)
+			}
+			if (J[triadidx[t]].add(J[triadidx[t + 1]]).compareTo(J[triadidx[t + 2]]) < 0) {
 				return res;
+			}
 		}
 
 		/*
@@ -310,14 +318,14 @@ public class Wigner3j {
 				 * others values are set in the triad. or it is still to
 				 * maintain its own explicit loop.
 				 */
-				int triadn = i / 3;
+				final int triadn = i / 3;
-				int triadr = i % 3;
+				final int triadr = i % 3;
 				/*
 				 * the neighbors in the triad have indices triadn*3+ (tiradr+1)
 				 * mod 3 and triadn*3+(triadr+2) mod3
 				 */
-				int nei1 = 3 * triadn + (triadr + 1) % 3;
+				final int nei1 = 3 * triadn + (triadr + 1) % 3;
-				int nei2 = 3 * triadn + (triadr + 2) % 3;
+				final int nei2 = 3 * triadn + (triadr + 2) % 3;
 
 				/*
 				 * found a candidate for which the two other values are already
@@ -331,11 +339,13 @@ public class Wigner3j {
 					 * rough work load estimator: basically (2J1+1)*(2J2+1)
 					 */
 					Rational wt = J[triadidx[i]].multiply(2).add(1);
-					if (M[triadidx[nei1]] == null)
+					if (M[triadidx[nei1]] == null) {
 						wt = wt.multiply(J[triadidx[nei1]].multiply(2).add(1));
-					if (M[triadidx[nei2]] == null)
+					}
+					if (M[triadidx[nei2]] == null) {
 						wt = wt.multiply(J[triadidx[nei2]].multiply(2).add(1));
-					int thiswt = wt.intValue();
+					}
+					final int thiswt = wt.intValue();
 					if (freeM < 0 || thiswt < freeMrank) {
 						freeM = i;
 						freeMrank = thiswt;
@@ -349,24 +359,26 @@ public class Wigner3j {
 			 * found an m-value which has not yet been summed over.
 			 */
 			if (M[triadidx[freeM]] == null) {
-				Rational[] childM = new Rational[M.length];
+				final Rational[] childM = new Rational[M.length];
-				for (int ji = 0; ji < M.length; ji++)
+				for (int ji = 0; ji < M.length; ji++) {
-					if (M[ji] != null)
+					if (M[ji] != null) {
 						childM[ji] = M[ji];
+					}
+				}
 
 				/*
 				 * two cases: value is fixed implicitly because already two
 				 * others values are set in the triad. or it is still to
 				 * maintain its own explicit loop.
 				 */
-				int triadn = freeM / 3;
+				final int triadn = freeM / 3;
-				int triadr = freeM % 3;
+				final int triadr = freeM % 3;
 				/*
 				 * the neighbors in the triad have indices triadn*3+ (triadr+1)
 				 * mod 3 and triadn*3+(triadr+2) mod3
 				 */
-				int nei1 = 3 * triadn + (triadr + 1) % 3;
+				final int nei1 = 3 * triadn + (triadr + 1) % 3;
-				int nei2 = 3 * triadn + (triadr + 2) % 3;
+				final int nei2 = 3 * triadn + (triadr + 2) % 3;
 				if (M[triadidx[nei1]] == null || M[triadidx[nei2]] == null) {
 					/*
 					 * The J-value is J[triadidx[freeM]]. Loop from -J to +J,
@@ -390,12 +402,14 @@ public class Wigner3j {
 					 * negate if these are the second occurrences of the J in
 					 * the triads
 					 */
-					if (tvec[nei1] < 0)
+					if (tvec[nei1] < 0) {
 						m1 = m1.negate();
-					if (tvec[nei2] < 0)
+					}
+					if (tvec[nei2] < 0) {
 						m2 = m2.negate();
+					}
 					/* m3 = -(m1+m2) */
-					Rational newm = tvec[freeM] > 0 ? m1.add(m2).negate() : m1.add(m2);
+					final Rational newm = tvec[freeM] > 0 ? m1.add(m2).negate() : m1.add(m2);
 					/*
 					 * No contribution if the m-value enforced by the other two
 					 * entries is outside the range -|J|..|J| enforced by its
@@ -429,34 +443,40 @@ public class Wigner3j {
 			 * negate if these are associated with in-flowing vectors in the
 			 * triads
 			 */
-			if (tvec[ji] < 0)
+			if (tvec[ji] < 0) {
 				m1 = m1.negate();
-			if (tvec[ji + 1] < 0)
+			}
+			if (tvec[ji + 1] < 0) {
 				m2 = m2.negate();
-			if (tvec[ji + 2] < 0)
+			}
+			if (tvec[ji + 2] < 0) {
 				m3 = m3.negate();
+			}
 			res = res.multiply(wigner3jm(J[triadidx[ji]], J[triadidx[ji + 1]], J[triadidx[ji + 2]], m1, m2, m3));
 
 			/*
 			 * if a partial product yields zero, the total product is zero, too,
 			 * and offers an early exit.
 			 */
-			if (res.signum() == 0)
+			if (res.signum() == 0) {
 				return BigSurdVec.ZERO;
+			}
 		}
 		/*
 		 * The overal sign is product_{J-Mpairs} (-1)^(J-M). This is an integer
 		 * because all the J-M are integer.
 		 */
 		Rational sig = new Rational();
-		for (int ji = 0; ji < J.length; ji++)
+		for (int ji = 0; ji < J.length; ji++) {
 			sig = sig.add(J[ji]).subtract(M[ji]);
+		}
 		/*
 		 * sign depends on the sum being even or odd. We assume that "sig" is
 		 * integer and look only at the numerator
 		 */
-		if (sig.a.abs().testBit(0))
+		if (sig.a.abs().testBit(0)) {
 			res = res.negate();
+		}
 		return res;
 	} /* wigner3j */
 
@@ -487,36 +507,42 @@ public class Wigner3j {
 		/*
 		 * Check that m1+m2+m3 = 0
 		 */
-		if (m1.add(m2).add(m3).signum() != 0)
+		if (m1.add(m2).add(m3).signum() != 0) {
 			return BigSurd.ZERO;
+		}
 
 		/*
 		 * Check that j1+j2+j3 is integer
 		 */
-		if (j1.add(j2).add(j3).isBigInteger() == false)
+		if (j1.add(j2).add(j3).isBigInteger() == false) {
 			return BigSurd.ZERO;
+		}
 
 		/*
 		 * Check that |j1-j2|<=j3 <= |j1+j2|
 		 */
-		Rational j1m2 = j1.subtract(j2);
+		final Rational j1m2 = j1.subtract(j2);
-		if (j1m2.abs().compareTo(j3) > 0)
+		if (j1m2.abs().compareTo(j3) > 0) {
 			return BigSurd.ZERO;
-		Rational j1p2 = j1.add(j2);
+		}
-		if (j1p2.abs().compareTo(j3) < 0)
+		final Rational j1p2 = j1.add(j2);
+		if (j1p2.abs().compareTo(j3) < 0) {
 			return BigSurd.ZERO;
+		}
 
 		/*
 		 * Check that |m_i| <= j_i
 		 */
-		if (m1.abs().compareTo(j1) > 0 || m2.abs().compareTo(j2) > 0 || m3.abs().compareTo(j3) > 0)
+		if (m1.abs().compareTo(j1) > 0 || m2.abs().compareTo(j2) > 0 || m3.abs().compareTo(j3) > 0) {
 			return BigSurd.ZERO;
+		}
 
 		/*
 		 * Check that m_i-j_i are integer.
 		 */
-		if (!m1.subtract(j1).isBigInteger() || !m2.subtract(j2).isBigInteger() || !m3.subtract(j3).isBigInteger())
+		if (!m1.subtract(j1).isBigInteger() || !m2.subtract(j2).isBigInteger() || !m3.subtract(j3).isBigInteger()) {
 			return BigSurd.ZERO;
+		}
 
 		/*
 		 * (-)^(j1-j2-m3)*delta(-m3,m1+m2)*sqrt[ (j3+j1-j2)! (j3-j1+j2)!
@@ -548,28 +574,31 @@ public class Wigner3j {
 			jj1m2k += k;
 		}
 
-		Factorial f = new Factorial();
+		final Factorial f = new Factorial();
 		Rational sumk = new Rational();
 		while (true) {
-			BigInteger d = f.at(k).multiply(f.at(j1j2jk)).multiply(f.at(j1m1k)).multiply(f.at(j2m2k)).multiply(f.at(jj2m1k)).multiply(f.at(jj1m2k));
+			final BigInteger d = f.at(k).multiply(f.at(j1j2jk)).multiply(f.at(j1m1k)).multiply(f.at(j2m2k)).multiply(f.at(jj2m1k)).multiply(f.at(jj1m2k));
-			if (k % 2 == 0)
+			if (k % 2 == 0) {
 				sumk = sumk.add(new Rational(BigInteger.ONE, d));
-			else
+			} else {
 				sumk = sumk.subtract(new Rational(BigInteger.ONE, d));
+			}
 			j1j2jk--;
 			j1m1k--;
 			j2m2k--;
 			jj2m1k++;
 			jj1m2k++;
-			if (j1j2jk < 0 || j1m1k < 0 || j2m2k < 0)
+			if (j1j2jk < 0 || j1m1k < 0 || j2m2k < 0) {
 				break;
+			}
 			k++;
 		}
 		/*
 		 * sign factor (-1)^(j1-j2-m3)
 		 */
-		if (j1m2.subtract(m3).intValue() % 2 != 0)
+		if (j1m2.subtract(m3).intValue() % 2 != 0) {
 			sumk = sumk.negate();
+		}
 
 		k = j1m2.add(j3).intValue();
 		BigInteger s = f.at(k);
@@ -591,7 +620,7 @@ public class Wigner3j {
 		s = s.multiply(f.at(k));
 		k = j1p2.add(j3).intValue();
 		k++;
-		Rational disc = new Rational(s, f.at(k));
+		final Rational disc = new Rational(s, f.at(k));
 		return new BigSurd(sumk, disc);
 	} /* wigner3jm */
 

src/org/nevec/rjm/Wigner3jGUI.java

@@ -79,12 +79,12 @@ public class Wigner3jGUI implements ActionListener, ListSelectionListener {
 		searJ.setLayoutOrientation(JList.HORIZONTAL_WRAP);
 		searJ.addListSelectionListener(this);
 
-		Font defFont = new Font("Monospaced", Font.PLAIN, 11);
+		final Font defFont = new Font("Monospaced", Font.PLAIN, 11);
 
 		fram.setBackground(new Color(250, 250, 250));
 		fram.setForeground(new Color(0, 0, 0));
-		Color fg = new Color(0, 200, 0);
+		final Color fg = new Color(0, 200, 0);
-		Color bg = new Color(10, 10, 10);
+		final Color bg = new Color(10, 10, 10);
 
 		gridbag = new GridBagLayout();
 		fram.setLayout(gridbag);
@@ -138,8 +138,8 @@ public class Wigner3jGUI implements ActionListener, ListSelectionListener {
 	 * @since 2010-08-27
 	 */
 	public void compute() throws Error {
-		String tr = inpGtria.getText();
+		final String tr = inpGtria.getText();
-		String[] trias = new String[4];
+		final String[] trias = new String[4];
 
 		/*
 		 * Read the trias configuration from inpGtria into trias[0..2], skipping
@@ -149,9 +149,10 @@ public class Wigner3jGUI implements ActionListener, ListSelectionListener {
 		for (int l = 0; l < 3;) {
 			try {
 				trias[l] = s.nextLine().trim();
-				if (!trias[l].startsWith("#"))
+				if (!trias[l].startsWith("#")) {
 					l++;
-			} catch (Exception e) {
+				}
+			} catch (final Exception e) {
 				s.close();
 				outG.setText("ERROR: less than 3 lines in the triad definition");
 				return;
@@ -163,28 +164,28 @@ public class Wigner3jGUI implements ActionListener, ListSelectionListener {
 		/*
 		 * Read the J values from inpGjval into trias[3] in a loop
 		 */
-		String j = inpGjval.getText();
+		final String j = inpGjval.getText();
 		s = new Scanner(j);
 		while (true) {
 			try {
 				trias[3] = s.nextLine().trim();
-			} catch (Exception e) {
+			} catch (final Exception e) {
 				s.close();
 				return;
 			}
 			if (!trias[3].startsWith("#")) {
 				try {
-					BigSurdVec w = Wigner3j.wigner3j(trias[0], trias[1], trias[2], trias[3]);
+					final BigSurdVec w = Wigner3j.wigner3j(trias[0], trias[1], trias[2], trias[3]);
 					outG.append(w.toString() + " = " + w.doubleValue());
-				} catch (Exception e) {
+				} catch (final Exception e) {
 					outG.append(e.toString());
 					e.printStackTrace();
 				}
 				outG.append(" # J = ");
-				Scanner num = new Scanner(trias[3]);
+				final Scanner num = new Scanner(trias[3]);
 				while (num.hasNextInt()) {
-					int twoj1 = num.nextInt();
+					final int twoj1 = num.nextInt();
-					Rational jfrac = new Rational(twoj1 - 1, 2);
+					final Rational jfrac = new Rational(twoj1 - 1, 2);
 					outG.append(jfrac.toString() + " ");
 				}
 				outG.append("\n");
@@ -202,7 +203,7 @@ public class Wigner3jGUI implements ActionListener, ListSelectionListener {
 	 */
 	@Override
 	public void actionPerformed(ActionEvent e) {
-		String lin = e.getActionCommand();
+		final String lin = e.getActionCommand();
 		/*
 		 * debugging System.out.println("Ac"+e.paramString()) ;
 		 * System.out.println(lin) ;
@@ -211,7 +212,7 @@ public class Wigner3jGUI implements ActionListener, ListSelectionListener {
 			outG.setText("");
 			try {
 				compute();
-			} catch (Error e1) {
+			} catch (final Error e1) {
 				// TODO Auto-generated catch block
 				e1.printStackTrace();
 			}
@@ -327,7 +328,7 @@ public class Wigner3jGUI implements ActionListener, ListSelectionListener {
 	 * @author Richard J. Mathar
 	 */
 	public static void main(String[] args) {
-		Wigner3jGUI g = new Wigner3jGUI();
+		final Wigner3jGUI g = new Wigner3jGUI();
 		g.init();
 	} /* main */
 

src/org/warp/picalculator/BMPFile.java

@@ -16,26 +16,26 @@ public class BMPFile extends Component {
 	// --- Private variable declaration
 	// --- Bitmap file header
 	@SuppressWarnings("unused")
-	private byte bitmapFileHeader[] = new byte[14];
+	private final byte bitmapFileHeader[] = new byte[14];
-	private byte bfType[] = { 'B', 'M' };
+	private final byte bfType[] = { 'B', 'M' };
 	private int bfSize = 0;
-	private int bfReserved1 = 0;
+	private final int bfReserved1 = 0;
-	private int bfReserved2 = 0;
+	private final int bfReserved2 = 0;
-	private int bfOffBits = BITMAPFILEHEADER_SIZE + BITMAPINFOHEADER_SIZE;
+	private final int bfOffBits = BITMAPFILEHEADER_SIZE + BITMAPINFOHEADER_SIZE;
 	// --- Bitmap info header
 	@SuppressWarnings("unused")
-	private byte bitmapInfoHeader[] = new byte[40];
+	private final byte bitmapInfoHeader[] = new byte[40];
-	private int biSize = BITMAPINFOHEADER_SIZE;
+	private final int biSize = BITMAPINFOHEADER_SIZE;
 	private int biWidth = 0;
 	private int biHeight = 0;
-	private int biPlanes = 1;
+	private final int biPlanes = 1;
-	private int biBitCount = 24;
+	private final int biBitCount = 24;
-	private int biCompression = 0;
+	private final int biCompression = 0;
 	private int biSizeImage = 0x030000;
-	private int biXPelsPerMeter = 0x0;
+	private final int biXPelsPerMeter = 0x0;
-	private int biYPelsPerMeter = 0x0;
+	private final int biYPelsPerMeter = 0x0;
-	private int biClrUsed = 0;
+	private final int biClrUsed = 0;
-	private int biClrImportant = 0;
+	private final int biClrImportant = 0;
 	// --- Bitmap raw data
 	private int bitmap[];
 	// --- File section
@@ -49,7 +49,7 @@ public class BMPFile extends Component {
 			fo = new FileOutputStream(parFilename);
 			save(parImage, parWidth, parHeight);
 			fo.close();
-		} catch (Exception saveEx) {
+		} catch (final Exception saveEx) {
 			saveEx.printStackTrace();
 		}
 	}
@@ -68,7 +68,7 @@ public class BMPFile extends Component {
 			writeBitmapFileHeader();
 			writeBitmapInfoHeader();
 			writeBitmap();
-		} catch (Exception saveEx) {
+		} catch (final Exception saveEx) {
 			saveEx.printStackTrace();
 		}
 	}
@@ -81,10 +81,10 @@ public class BMPFile extends Component {
 	private boolean convertImage(Image parImage, int parWidth, int parHeight) {
 		int pad;
 		bitmap = new int[parWidth * parHeight];
-		PixelGrabber pg = new PixelGrabber(parImage, 0, 0, parWidth, parHeight, bitmap, 0, parWidth);
+		final PixelGrabber pg = new PixelGrabber(parImage, 0, 0, parWidth, parHeight, bitmap, 0, parWidth);
 		try {
 			pg.grabPixels();
-		} catch (InterruptedException e) {
+		} catch (final InterruptedException e) {
 			e.printStackTrace();
 			return (false);
 		}
@@ -113,11 +113,13 @@ public class BMPFile extends Component {
 		int lastRowIndex;
 		int pad;
 		int padCount;
-		byte rgb[] = new byte[3];
+		final byte rgb[] = new byte[3];
 		size = (biWidth * biHeight) - 1;
 		pad = 4 - ((biWidth * 3) % 4);
-		if (pad == 4) // <==== Bug correction
+		if (pad == 4)
+		 {
 			pad = 0; // <==== Bug correction
+		}
 		rowCount = 1;
 		padCount = 0;
 		rowIndex = size - biWidth;
@@ -137,14 +139,15 @@ public class BMPFile extends Component {
 					rowCount = 1;
 					rowIndex = lastRowIndex - biWidth;
 					lastRowIndex = rowIndex;
-				} else
+				} else {
 					rowCount++;
+				}
 				rowIndex++;
 			}
 			// --- Update the size of the file
 			bfSize += padCount - pad;
 			biSizeImage += padCount - pad;
-		} catch (Exception wb) {
+		} catch (final Exception wb) {
 			wb.printStackTrace();
 		}
 	}
@@ -160,7 +163,7 @@ public class BMPFile extends Component {
 			fo.write(intToWord(bfReserved1));
 			fo.write(intToWord(bfReserved2));
 			fo.write(intToDWord(bfOffBits));
-		} catch (Exception wbfh) {
+		} catch (final Exception wbfh) {
 			wbfh.printStackTrace();
 		}
 	}
@@ -184,7 +187,7 @@ public class BMPFile extends Component {
 			fo.write(intToDWord(biYPelsPerMeter));
 			fo.write(intToDWord(biClrUsed));
 			fo.write(intToDWord(biClrImportant));
-		} catch (Exception wbih) {
+		} catch (final Exception wbih) {
 			wbih.printStackTrace();
 		}
 	}
@@ -196,7 +199,7 @@ public class BMPFile extends Component {
 	 *
 	 */
 	private byte[] intToWord(int parValue) {
-		byte retValue[] = new byte[2];
+		final byte retValue[] = new byte[2];
 		retValue[0] = (byte) (parValue & 0x00FF);
 		retValue[1] = (byte) ((parValue >> 8) & 0x00FF);
 		return (retValue);
@@ -209,7 +212,7 @@ public class BMPFile extends Component {
 	 *
 	 */
 	private byte[] intToDWord(int parValue) {
-		byte retValue[] = new byte[4];
+		final byte retValue[] = new byte[4];
 		retValue[0] = (byte) (parValue & 0x00FF);
 		retValue[1] = (byte) ((parValue >> 8) & 0x000000FF);
 		retValue[2] = (byte) ((parValue >> 16) & 0x000000FF);

src/org/warp/picalculator/KeyboardTest.java

@@ -0,0 +1,10 @@
+package org.warp.picalculator;
+
+import org.warp.picalculator.gui.screens.KeyboardDebugScreen;
+
+public class KeyboardTest {
+
+	public static void main(String[] args) throws InterruptedException {
+		new Main(new KeyboardDebugScreen());
+	}
+}

src/org/warp/picalculator/Main.java

@@ -1,8 +1,9 @@
 package org.warp.picalculator;
 
 import org.warp.picalculator.device.Keyboard;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.screens.LoadingScreen;
+import org.warp.picalculator.gui.screens.Screen;
 
 import com.pi4j.wiringpi.Gpio;
 
@@ -12,13 +13,19 @@ public class Main {
 	public static final boolean zoomed = true;
 	public static Main instance;
 	public static boolean haxMode = true;
+	public static String[] args;
 
-	public Main() throws InterruptedException {
+	public Main(String[] args) throws InterruptedException {
+		this(new LoadingScreen(), args);
+	}
+
+	public Main(Screen screen, String[] args) {
 		instance = this;
 		Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
 		Thread.currentThread().setName("Main thread");
+		this.args = args;
 		beforeStart();
-		new PIDisplay(new LoadingScreen());
+		new DisplayManager(screen);
 		Utils.debug.println("Shutdown...");
 		beforeShutdown();
 		Utils.debug.println("");
@@ -27,19 +34,15 @@ public class Main {
 	}
 
 	public void beforeStart() {
-		if (System.getProperty("os.name").equals("Linux")) {
+		if (Utils.isRunningOnRaspberry() && !Utils.isInArray("-noraspi", args)) {
 			Gpio.wiringPiSetupPhys();
 			Gpio.pinMode(12, Gpio.PWM_OUTPUT);
 		} else {
-			screenPos = new int[]{0,0};
+			screenPos = new int[] { 0, 0 };
 			Utils.debugOn = true;
 		}
 		Utils.debugThirdScreen = Utils.debugOn & false;
-		PIDisplay.setBrightness(0.5f);
+		DisplayManager.setBrightness(0.5f);
-	}
-
-	
-	public void afterStart() {
 		Keyboard.startKeyboard();
 	}
 
@@ -48,6 +51,6 @@ public class Main {
 	}
 
 	public static void main(String[] args) throws InterruptedException {
-		new Main();
+		new Main(args);
 	}
 }

src/org/warp/picalculator/TestGPU.java

@@ -1,56 +1,84 @@
 package org.warp.picalculator;
 
-import org.warp.picalculator.gui.PIDisplay;
+import java.io.IOException;
+
 import org.warp.picalculator.gui.graphicengine.Display;
 import org.warp.picalculator.gui.graphicengine.Drawable;
 import org.warp.picalculator.gui.graphicengine.RAWFont;
-import org.warp.picalculator.gui.graphicengine.Renderer;
+import org.warp.picalculator.gui.graphicengine.RAWSkin;
 import org.warp.picalculator.gui.graphicengine.gpu.GPUDisplay;
 import org.warp.picalculator.gui.graphicengine.gpu.GPURenderer;
-import org.warp.picalculator.gui.screens.LoadingScreen;
+import org.warp.picalculator.gui.screens.KeyboardDebugScreen;
+import org.warp.picalculator.gui.screens.MarioScreen;
+
+import java.lang.management.ManagementFactory;
+import java.lang.management.OperatingSystemMXBean;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.ArrayList;
 
 public class TestGPU {
 
 	public static final GPUDisplay d = new GPUDisplay();
 
-	public static void main(String[] args) {
+	public static void main(String[] args) throws IOException {
+		new Main(new KeyboardDebugScreen());
+		if (true) return;
 		Utils.debugOn = true;
 		Utils.debugThirdScreen = false;
 		d.create();
 
-		Scene s = new Scene(d);
+		final Scene s = new Scene(d);
 	}
 
 	private static class Scene implements Drawable {
 
-		private RAWFont[] fonts;
+		private RAWFont exampleFont;
-		private int[] textures;
+		private final RAWSkin exampleSkin;
 
-		private GPURenderer r;
+		private final GPURenderer r;
-		private Display d;
+		private final Display d;
 
-		public Scene(Display d) {
+		public Scene(Display d) throws IOException {
 			this.d = d;
-			this.r = (GPURenderer) d.getRenderer();
+			r = (GPURenderer) d.getRenderer();
+
+			exampleFont = d.loadFont("ex");
+
+			exampleSkin = d.loadSkin("skin.png");
+
 			d.start(this);
 
 //			fonts = new RAWFont[1];
 //			textures = new int[100];
 //			fonts[0] = new RAWFont();
 //			fonts[0].create("big");
-			new Thread(()->{
+			new Thread(() -> {
 				try {
-					Thread.sleep(60000);
+					for (int i = 0; i < 12; i++) {
-				} catch (InterruptedException e) {
+						Utils.printSystemResourcesUsage();
+						Thread.sleep(5000);
+					}
+				} catch (final InterruptedException e) {
 					// TODO Auto-generated catch block
 					e.printStackTrace();
 				}
 				System.exit(0);
 			}).start();
+			
+			d.waitUntilExit();
 		}
 
 		@Override
 		public void refresh() {
+			exampleSkin.use(d);
+			r.glClearColor(0xFFD0FDCF);
+			r.glClear(d.getWidth(), d.getHeight());
+			r.glColor3f(1.0f, 1.0f, 1.0f);
+			r.glFillRect(2, 2, 160, 160, 0, 0, 16, 16);
+			exampleFont.use(d);
+			r.glColor3f(1, 0, 0);
+			r.glDrawStringLeft(10, 170, "Prova! 123456789");
 		}
 
 	}

src/org/warp/picalculator/Utils.java

@@ -1,9 +1,17 @@
 package org.warp.picalculator;
 
+import java.io.BufferedReader;
 import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.InputStreamReader;
 import java.io.StringWriter;
+import java.lang.management.ManagementFactory;
+import java.lang.management.OperatingSystemMXBean;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.math.RoundingMode;
@@ -12,7 +20,7 @@ import java.util.List;
 
 import org.nevec.rjm.BigDecimalMath;
 import org.nevec.rjm.Rational;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.RAWFont;
 import org.warp.picalculator.math.functions.AnteriorFunction;
 import org.warp.picalculator.math.functions.Division;
@@ -61,7 +69,7 @@ public class Utils {
 
 	public static boolean isInArray(String ch, String[] a) {
 		boolean contains = false;
-		for (String c : a) {
+		for (final String c : a) {
 			if (c.equals(ch)) {
 				contains = true;
 				break;
@@ -70,13 +78,13 @@ public class Utils {
 		return contains;
 	}
 
-	private static final String[] regexNormalSymbols = new String[]{"\\", ".", "[", "]", "{", "}", "(", ")", "*", "+", "-", "?", "^", "$", "|"};
+	private static final String[] regexNormalSymbols = new String[] { "\\", ".", "[", "]", "{", "}", "(", ")", "*", "+", "-", "?", "^", "$", "|" };
 
 	public static String ArrayToRegex(String[] array) {
 		String regex = null;
-		for (String symbol : array) {
+		for (final String symbol : array) {
 			boolean contained = false;
-			for (String smb : regexNormalSymbols) {
+			for (final String smb : regexNormalSymbols) {
 				if (smb.equals(symbol)) {
 					contained = true;
 					break;
@@ -100,17 +108,17 @@ public class Utils {
 	}
 
 	public static String[] concat(String[] a, String[] b) {
-		int aLen = a.length;
+		final int aLen = a.length;
-		int bLen = b.length;
+		final int bLen = b.length;
-		String[] c = new String[aLen + bLen];
+		final String[] c = new String[aLen + bLen];
 		System.arraycopy(a, 0, c, 0, aLen);
 		System.arraycopy(b, 0, c, aLen, bLen);
 		return c;
 	}
 
 	public static String[] add(String[] a, String b) {
-		int aLen = a.length;
+		final int aLen = a.length;
-		String[] c = new String[aLen + 1];
+		final String[] c = new String[aLen + 1];
 		System.arraycopy(a, 0, c, 0, aLen);
 		c[aLen] = b;
 		return c;
@@ -249,7 +257,7 @@ public class Utils {
 
 	public static boolean areThereOtherSettedUpFunctions(ArrayList<Function> fl) {
 		for (int i = 0; i < fl.size(); i++) {
-			if (!(fl.get(i) instanceof Number || fl.get(i) instanceof Variable || fl.get(i) instanceof Sum ||  fl.get(i) instanceof SumSubtraction || fl.get(i) instanceof Expression || fl.get(i) instanceof AnteriorFunction || fl.get(i) instanceof Multiplication || fl.get(i) instanceof Division)) {
+			if (!(fl.get(i) instanceof Number || fl.get(i) instanceof Variable || fl.get(i) instanceof Sum || fl.get(i) instanceof SumSubtraction || fl.get(i) instanceof Expression || fl.get(i) instanceof AnteriorFunction || fl.get(i) instanceof Multiplication || fl.get(i) instanceof Division)) {
 				if (fl.get(i) instanceof AnteriorFunction) {
 					if (((AnteriorFunction) fl.get(i)).getVariable() == null) {
 						return true;
@@ -269,7 +277,7 @@ public class Utils {
 	public static Rational getRational(BigDecimal str) {
 		try {
 			return getRational(str.toString());
-		} catch (Error e) {
+		} catch (final Error e) {
 			//E' IMPOSSIBILE CHE VENGA THROWATO UN ERRORE
 			return new Rational("0");
 		}
@@ -278,17 +286,17 @@ public class Utils {
 	public static Rational getRational(String str) throws Error {
 		try {
 			return new Rational(str);
-		} catch (NumberFormatException ex) {
+		} catch (final NumberFormatException ex) {
 			if (new BigDecimal(str).compareTo(new BigDecimal(8000.0)) < 0 && new BigDecimal(str).compareTo(new BigDecimal(-8000.0)) > 0) {
 				if (str.equals("-")) {
 					str = "-1";
 				}
-				long bits = Double.doubleToLongBits(Double.parseDouble(str));
+				final long bits = Double.doubleToLongBits(Double.parseDouble(str));
 
-				long sign = bits >>> 63;
+				final long sign = bits >>> 63;
-				long exponent = ((bits >>> 52) ^ (sign << 11)) - 1023;
+				final long exponent = ((bits >>> 52) ^ (sign << 11)) - 1023;
-				long fraction = bits << 12; // bits are "reversed" but that's
+				final long fraction = bits << 12; // bits are "reversed" but that's
-											// not a problem
+				// not a problem
 
 				long a = 1L;
 				long b = 1L;
@@ -298,13 +306,15 @@ public class Utils {
 					b *= 2;
 				}
 
-				if (exponent > 0)
+				if (exponent > 0) {
 					a *= 1 << exponent;
-				else
+				} else {
 					b *= 1 << -exponent;
+				}
 
-				if (sign == 1)
+				if (sign == 1) {
 					a *= -1;
+				}
 
 				if (b == 0) {
 					a = 0;
@@ -313,11 +323,11 @@ public class Utils {
 
 				return new Rational(new BigInteger(a + ""), new BigInteger(b + ""));
 			} else {
-				BigDecimal original = new BigDecimal(str);
+				final BigDecimal original = new BigDecimal(str);
 
-				BigInteger numerator = original.unscaledValue();
+				final BigInteger numerator = original.unscaledValue();
 
-				BigInteger denominator = BigDecimalMath.pow(BigDecimal.TEN, new BigDecimal(original.scale())).toBigIntegerExact();
+				final BigInteger denominator = BigDecimalMath.pow(BigDecimal.TEN, new BigDecimal(original.scale())).toBigIntegerExact();
 
 				return new Rational(numerator, denominator);
 			}
@@ -332,7 +342,7 @@ public class Utils {
 		if (variables.size() != variables2.size()) {
 			return false;
 		} else {
-			for (Variable v : variables) {
+			for (final Variable v : variables) {
 				if (!variables2.contains(v)) {
 					return false;
 				}
@@ -343,17 +353,17 @@ public class Utils {
 
 	public static void writeSquareRoot(Function var, int x, int y, boolean small) {
 		var.setSmall(small);
-		int w1 = var.getWidth();
+		final int w1 = var.getWidth();
-		int h1 = var.getHeight();
+		final int h1 = var.getHeight();
-		int wsegno = 5;
+		final int wsegno = 5;
-		int hsegno = h1 + 2;
+		final int hsegno = h1 + 2;
 
 		var.draw(x + wsegno, y + (hsegno - h1));
 
-		PIDisplay.renderer.glDrawLine(x + 1, y + hsegno - 3, x + 3, y + hsegno - 1);
+		DisplayManager.renderer.glDrawLine(x + 1, y + hsegno - 3, x + 3, y + hsegno - 1);
-		PIDisplay.renderer.glDrawLine(x + 3, y + (hsegno - 1) / 2 + 1, x + 3, y + hsegno - 1);
+		DisplayManager.renderer.glDrawLine(x + 3, y + (hsegno - 1) / 2 + 1, x + 3, y + hsegno - 1);
-		PIDisplay.renderer.glDrawLine(x + 4, y, x + 4, y + (hsegno - 1) / 2);
+		DisplayManager.renderer.glDrawLine(x + 4, y, x + 4, y + (hsegno - 1) / 2);
-		PIDisplay.renderer.glDrawLine(x + 4, y, x + 4 + 1 + w1 + 1, y);
+		DisplayManager.renderer.glDrawLine(x + 4, y, x + 4 + 1 + w1 + 1, y);
 	}
 
 	public static final int getFontHeight() {
@@ -365,7 +375,7 @@ public class Utils {
 	}
 
 	public static final RAWFont getFont(boolean small, boolean zoomed) {
-		return PIDisplay.fonts[getFontIndex(small, zoomed)];
+		return DisplayManager.fonts[getFontIndex(small, zoomed)];
 	}
 
 	public static final int getFontIndex(boolean small, boolean zoomed) {
@@ -391,44 +401,44 @@ public class Utils {
 	public static final int getFontHeight(boolean small, boolean zoomed) {
 		if (small) {
 			if (zoomed) {
-				return PIDisplay.glyphsHeight[3];
+				return DisplayManager.glyphsHeight[3];
 			} else {
-				return PIDisplay.glyphsHeight[1];
+				return DisplayManager.glyphsHeight[1];
 			}
 		} else {
 			if (zoomed) {
-				return PIDisplay.glyphsHeight[2];
+				return DisplayManager.glyphsHeight[2];
 			} else {
-				return PIDisplay.glyphsHeight[0];
+				return DisplayManager.glyphsHeight[0];
 			}
 		}
 	}
 
 	public static byte[] convertStreamToByteArray(InputStream stream, long size) throws IOException {
 
-	    // check to ensure that file size is not larger than Integer.MAX_VALUE.
+		// check to ensure that file size is not larger than Integer.MAX_VALUE.
-	    if (size > Integer.MAX_VALUE) {
+		if (size > Integer.MAX_VALUE) {
-	        return new byte[0];
+			return new byte[0];
-	    }
+		}
 
-	    byte[] buffer = new byte[(int)size];
+		final byte[] buffer = new byte[(int) size];
-	    ByteArrayOutputStream os = new ByteArrayOutputStream();
+		final ByteArrayOutputStream os = new ByteArrayOutputStream();
 
-	    int line = 0;
+		int line = 0;
-	    // read bytes from stream, and store them in buffer
+		// read bytes from stream, and store them in buffer
-	    while ((line = stream.read(buffer)) != -1) {
+		while ((line = stream.read(buffer)) != -1) {
-	        // Writes bytes from byte array (buffer) into output stream.
+			// Writes bytes from byte array (buffer) into output stream.
-	        os.write(buffer, 0, line);
+			os.write(buffer, 0, line);
-	    }
+		}
-	    stream.close();
+		stream.close();
-	    os.flush();
+		os.flush();
-	    os.close();
+		os.close();
-	    return os.toByteArray();
+		return os.toByteArray();
 	}
 
 	public static int[] realBytes(byte[] bytes) {
-		int len = bytes.length;
+		final int len = bytes.length;
-		int[] realbytes = new int[len];
+		final int[] realbytes = new int[len];
 		for (int i = 0; i < len; i++) {
 			realbytes[i] = Byte.toUnsignedInt(bytes[i]);
 		}
@@ -436,7 +446,7 @@ public class Utils {
 	}
 
 	public static boolean allSolved(List<Function> expressions) throws Error {
-		for (Function itm : expressions) {
+		for (final Function itm : expressions) {
 			if (itm.isSolved() == false) {
 				return false;
 			}
@@ -445,22 +455,26 @@ public class Utils {
 	}
 
 	public static Function[][] joinFunctionsResults(List<Function> l1, List<Function> l2) {
-		int size1 = l1.size();
+		final int size1 = l1.size();
-		int size2 = l2.size();
+		final int size2 = l2.size();
 		int cur1 = 0;
 		int cur2 = 0;
-		int total = l1.size()*l2.size();
+		final int total = l1.size() * l2.size();
-		Function[][] results = new Function[total][2];
+		final Function[][] results = new Function[total][2];
 		for (int i = 0; i < total; i++) {
-			results[i] = new Function[]{l1.get(cur1), l2.get(cur2)};
+			results[i] = new Function[] { l1.get(cur1), l2.get(cur2) };
 			if (i % size2 == 0) {
-				cur1+=1;
+				cur1 += 1;
 			}
 			if (i % size1 == 0) {
-				cur2+=1;
+				cur2 += 1;
+			}
+			if (cur1 >= size1) {
+				cur1 = 0;
+			}
+			if (cur2 >= size2) {
+				cur2 = 0;
 			}
-			if (cur1 >= size1) cur1 = 0;
-			if (cur2 >= size2) cur2 = 0;
 		}
 		return results;
 	}
@@ -477,28 +491,97 @@ public class Utils {
 	public static CharSequence multipleChars(String string, int i) {
 		String result = "";
 		for (int j = 0; j < i; j++) {
-			result+=string;
+			result += string;
 		}
 		return result;
 	}
 
 	public static boolean isIntegerValue(BigDecimal bd) {
-		 return bd.signum() == 0 || bd.scale() <= 0 || bd.stripTrailingZeros().scale() <= 0;
+		return bd.signum() == 0 || bd.scale() <= 0 || bd.stripTrailingZeros().scale() <= 0;
 	}
 
 	public static <T> String arrayToString(T... data) {
 		String sdata = "";
-		for (T o : data) {
+		for (final T o : data) {
-			sdata += ","+o.toString();
+			sdata += "," + o.toString();
 		}
 		return sdata.substring(1);
 	}
 
 	public static String arrayToString(boolean... data) {
 		String sdata = "";
-		for (boolean o : data) {
+		for (final boolean o : data) {
-			sdata += (o)?1:0;
+			sdata += (o) ? 1 : 0;
 		}
 		return sdata;
 	}
+
+	public static void printSystemResourcesUsage() {
+		System.out.println("============");
+		OperatingSystemMXBean operatingSystemMXBean = ManagementFactory.getOperatingSystemMXBean();
+		for (Method method : operatingSystemMXBean.getClass().getDeclaredMethods()) {
+			method.setAccessible(true);
+			if (method.getName().startsWith("get") && Modifier.isPublic(method.getModifiers())) {
+				Object value;
+				try {
+					value = method.invoke(operatingSystemMXBean);
+				} catch (Exception e) {
+					value = e;
+				} // try
+				boolean percent = false;
+				boolean mb = false;
+				String displayName = method.getName();
+				String displayValue = value.toString();
+				if (displayName.endsWith("CpuLoad")) {
+					percent = true;
+				}
+				if (displayName.endsWith("MemorySize")) {
+					mb = true;
+				}
+				ArrayList<String> arr = new ArrayList<>();
+				arr.add("getFreePhysicalMemorySize");
+				arr.add("getProcessCpuLoad");
+				arr.add("getSystemCpuLoad");
+				arr.add("getTotalPhysicalMemorySize");
+				if (arr.contains(displayName)) {
+					if (percent) {
+						try {
+							System.out.println(displayName + " = " + (((int)(Float.parseFloat(displayValue) * 10000f))/100f) + "%");
+						}catch(Exception ex) {
+							System.out.println(displayName + " = " + displayValue);
+						}
+					} else if (mb) {
+						try {
+							System.out.println(displayName + " = " + (Long.parseLong(displayValue) / 1024L / 1024L) + " MB");
+						}catch(Exception ex) {
+							System.out.println(displayName + " = " + displayValue);
+						}
+					} else {
+						System.out.println(displayName + " = " + displayValue);
+					}
+				}
+			} // if
+		} // for
+		System.out.println("============");
+	}
+
+	public static boolean isRunningOnRaspberry() {
+		if (System.getProperty("os.name").equals("Linux")) {
+	        final File file = new File("/etc", "os-release");
+	        try (FileInputStream fis = new FileInputStream(file);
+	             BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(fis))) {
+	            String string;
+	            while ((string = bufferedReader.readLine()) != null) {
+	                if (string.toLowerCase().contains("raspbian")) {
+	                    if (string.toLowerCase().contains("name")) {
+	                    	return true;
+	                    }
+	                }
+	            }
+	        } catch (final Exception e) {
+	            e.printStackTrace();
+	        }
+	    }
+		return false;
+	}
 }

src/org/warp/picalculator/device/Keyboard.java

@@ -5,8 +5,7 @@ import java.awt.event.KeyEvent;
 import org.warp.picalculator.Utils;
 import org.warp.picalculator.device.chip.ParallelToSerial;
 import org.warp.picalculator.device.chip.SerialToParallel;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.gui.screens.KeyboardDebugScreen;
 import org.warp.picalculator.gui.screens.MarioScreen;
 import org.warp.picalculator.gui.screens.Screen;
@@ -29,21 +28,20 @@ public class Keyboard {
 
 	private static volatile boolean[][] precedentStates = new boolean[8][8];
 	public static volatile boolean[][] debugKeysDown = new boolean[8][8];
-	public static volatile KeyEvent debugKeyEvent;
+	public static volatile int debugKeyCode = -1;
 
 	public static void startKeyboard() {
-		Thread kt = new Thread(()->{
+		final Thread kt = new Thread(() -> {
 			if (Utils.debugOn) {
 				try {
-					while(true) {
+					while (true) {
-						if (debugKeyEvent != null) {
+						if (debugKeyCode != -1) {
-							debugKeyPressed(debugKeyEvent);
+							debugKeyPressed(debugKeyCode);
-							debugKeyEvent = null;
+							debugKeyCode = -1;
 						}
 						Thread.sleep(50);
 					}
-				} catch (InterruptedException e) {
+				} catch (final InterruptedException e) {}
-				}
 			} else {
 				Gpio.pinMode(CLK_INH_pin, Gpio.OUTPUT);
 				Gpio.pinMode(RCK_pin, Gpio.OUTPUT);
@@ -58,12 +56,12 @@ public class Keyboard {
 				Gpio.digitalWrite(SH_LD_pin, false);
 				Gpio.digitalWrite(SCK_and_CLK_pin, false);
 				Gpio.digitalWrite(QH_pin, false);
-				SerialToParallel chip1 = new SerialToParallel(RCK_pin, SCK_and_CLK_pin /*SCK*/, SER_pin);
+				final SerialToParallel chip1 = new SerialToParallel(RCK_pin, SCK_and_CLK_pin /*SCK*/, SER_pin);
-				ParallelToSerial chip2 = new ParallelToSerial(SH_LD_pin, CLK_INH_pin, QH_pin, SCK_and_CLK_pin/*CLK*/);
+				final ParallelToSerial chip2 = new ParallelToSerial(SH_LD_pin, CLK_INH_pin, QH_pin, SCK_and_CLK_pin/*CLK*/);
 
 				KeyboardDebugScreen.log("Started keyboard system");
 
-				while(true) {
+				while (true) {
 					boolean[] data;
 					for (int col = 0; col < 8; col++) {
 						data = new boolean[8];
@@ -75,12 +73,12 @@ public class Keyboard {
 
 						for (int row = 0; row < 8; row++) {
 							if (data[row] == true && precedentStates[row][col] == false) {
-								System.out.println("Pressed button at "+(row+1) +", "+(col+1));
+								System.out.println("Pressed button at " + (row + 1) + ", " + (col + 1));
-								KeyboardDebugScreen.log("Pressed button at "+(row+1) +", "+(col+1));
+								KeyboardDebugScreen.log("Pressed button at " + (row + 1) + ", " + (col + 1));
-								keyPressedRaw(row+1, col+1);
+								keyPressedRaw(row + 1, col + 1);
 							} else if (data[row] == false && precedentStates[row][col] == true) {
-								keyReleasedRaw(row+1, col+1);
+								keyReleasedRaw(row + 1, col + 1);
-								KeyboardDebugScreen.log("Released button at "+(row+1) +", "+(col+1));
+								KeyboardDebugScreen.log("Released button at " + (row + 1) + ", " + (col + 1));
 							}
 							precedentStates[row][col] = data[row];
 						}
@@ -94,8 +92,8 @@ public class Keyboard {
 		kt.start();
 	}
 
-	private static void debugKeyPressed(KeyEvent arg0) {
+	private static void debugKeyPressed(int keyCode) {
-		switch (arg0.getKeyCode()) {
+		switch (keyCode) {
 			case KeyEvent.VK_ESCAPE:
 				Keyboard.keyPressed(Key.POWER);
 				break;
@@ -177,6 +175,7 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_ENTER:
 			case KeyEvent.VK_ENTER:
 				if (Keyboard.shift) {
 					Keyboard.keyPressed(Key.SIMPLIFY);
@@ -187,7 +186,7 @@ public class Keyboard {
 				}
 				int row = 2;
 				int col = 1;
-				Keyboard.debugKeysDown[row-1][col-1] = true;
+				Keyboard.debugKeysDown[row - 1][col - 1] = true;
 				break;
 			case KeyEvent.VK_1:
 				if (!Keyboard.shift && !Keyboard.alpha) {
@@ -265,6 +264,7 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_ADD:
 			case KeyEvent.VK_ADD:
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.PLUS);
@@ -274,6 +274,7 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_SUBTRACT:
 			case KeyEvent.VK_SUBTRACT:
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.MINUS);
@@ -281,6 +282,7 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_MULTIPLY:
 			case KeyEvent.VK_MULTIPLY:
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.MULTIPLY);
@@ -288,6 +290,7 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_DIVIDE:
 			case KeyEvent.VK_DIVIDE:
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.DIVIDE);
@@ -302,6 +305,7 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_DELETE:
 			case KeyEvent.VK_DELETE:
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.RESET);
@@ -309,28 +313,31 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_LEFT:
 			case KeyEvent.VK_LEFT:
 				//LEFT
 				row = 2;
 				col = 3;
-				Keyboard.debugKeysDown[row-1][col-1] = true;
+				Keyboard.debugKeysDown[row - 1][col - 1] = true;
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.LEFT);
 				} else {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_RIGHT:
 			case KeyEvent.VK_RIGHT:
 				//RIGHT
 				row = 2;
 				col = 5;
-				Keyboard.debugKeysDown[row-1][col-1] = true;
+				Keyboard.debugKeysDown[row - 1][col - 1] = true;
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.RIGHT);
 				} else {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_NUMPAD4:
 			case KeyEvent.VK_NUMPAD4:
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.HISTORY_BACK);
@@ -338,6 +345,7 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_NUMPAD6:
 			case KeyEvent.VK_NUMPAD6:
 				if (!Keyboard.shift && !Keyboard.alpha) {
 					Keyboard.keyPressed(Key.HISTORY_FORWARD);
@@ -352,21 +360,26 @@ public class Keyboard {
 					Keyboard.keyPressed(Key.NONE);
 				}
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_SHIFT:
 			case KeyEvent.VK_SHIFT:
 				Keyboard.keyPressed(Key.SHIFT);
 				break;
 			case KeyEvent.VK_A:
 				Keyboard.keyPressed(Key.ALPHA);
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_NUMPAD1:
 			case KeyEvent.VK_NUMPAD1:
 				Keyboard.keyPressed(Key.SQRT);
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_NUMPAD2:
 			case KeyEvent.VK_NUMPAD2:
 				Keyboard.keyPressed(Key.ROOT);
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_NUMPAD3:
 			case KeyEvent.VK_NUMPAD3:
 				Keyboard.keyPressed(Key.POWER_OF_2);
 				break;
+			case com.jogamp.newt.event.KeyEvent.VK_NUMPAD5:
 			case KeyEvent.VK_NUMPAD5:
 				Keyboard.keyPressed(Key.POWER_OF_x);
 				break;
@@ -375,9 +388,9 @@ public class Keyboard {
 
 	public static boolean isKeyDown(int row, int col) {
 		if (Utils.debugOn == false) {
-			return precedentStates[row-1][col-1];
+			return precedentStates[row - 1][col - 1];
 		} else {
-			return debugKeysDown[row-1][col-1];
+			return debugKeysDown[row - 1][col - 1];
 		}
 	}
 
@@ -395,7 +408,7 @@ public class Keyboard {
 		if (row == 1 && col == 1) {
 			keyPressed(Key.SHIFT);
 		} else if (row == 1 && col == 2) {
-				keyPressed(Key.ALPHA);
+			keyPressed(Key.ALPHA);
 		} else if (row == 1 && col == 7) {
 			if (shift) {
 				keyPressed(Key.BRIGHTNESS_CYCLE_REVERSE);
@@ -580,7 +593,7 @@ public class Keyboard {
 			} else {
 				keyPressed(Key.LEFT);
 			}
-		} else if (row ==2 && col == 5) {
+		} else if (row == 2 && col == 5) {
 			if (shift) {
 				keyPressed(Key.NONE);
 			} else if (alpha) {
@@ -664,8 +677,7 @@ public class Keyboard {
 				System.out.println("PREMUTO >");
 				keyPressed(Key.HISTORY_FORWARD);
 			}
-		} else {
+		} else {}
-		}
 	}
 
 	public static void stopKeyboard() {
@@ -680,15 +692,15 @@ public class Keyboard {
 	}
 
 	public static void keyPressed(Key k) {
-		if (PIDisplay.INSTANCE != null) {
+		if (DisplayManager.INSTANCE != null) {
-			Screen scr = PIDisplay.INSTANCE.getScreen();
+			final Screen scr = DisplayManager.INSTANCE.getScreen();
 			boolean refresh = false;
-			if(scr != null && scr.initialized && scr.keyPressed(k)) {
+			if (scr != null && scr.initialized && scr.keyPressed(k)) {
 				refresh = true;
 			} else {
 				switch (k) {
 					case POWER:
-						PIDisplay.display.destroy();
+						DisplayManager.display.destroy();
 						break;
 					case NONE:
 						break;
@@ -696,20 +708,20 @@ public class Keyboard {
 						letterPressed('X');
 						break;
 					case BRIGHTNESS_CYCLE:
-						PIDisplay.cycleBrightness(false);
+						DisplayManager.cycleBrightness(false);
 						refresh = true;
 						break;
 					case BRIGHTNESS_CYCLE_REVERSE:
-						PIDisplay.INSTANCE.setScreen(new MarioScreen()); //TODO: rimuovere: prova
+						DisplayManager.INSTANCE.setScreen(new MarioScreen()); //TODO: rimuovere: prova
-						PIDisplay.cycleBrightness(true);
+						DisplayManager.cycleBrightness(true);
 						refresh = true;
 						break;
 					case HISTORY_BACK:
-						PIDisplay.INSTANCE.goBack();
+						DisplayManager.INSTANCE.goBack();
 						refresh = true;
 						break;
 					case HISTORY_FORWARD:
-						PIDisplay.INSTANCE.goForward();
+						DisplayManager.INSTANCE.goForward();
 						refresh = true;
 						break;
 					default:
@@ -736,7 +748,7 @@ public class Keyboard {
 				refresh = true;
 			}
 			if (refresh) {
-				PIDisplay.display.repaint();
+//				PIDisplay.display.repaint();
 			}
 		}
 	}
@@ -747,9 +759,9 @@ public class Keyboard {
 
 	public static void keyReleased(Key k) {
 		boolean refresh = false;
-		if (PIDisplay.INSTANCE != null) {
+		if (DisplayManager.INSTANCE != null) {
-			Screen scr = PIDisplay.INSTANCE.getScreen();
+			final Screen scr = DisplayManager.INSTANCE.getScreen();
-			if(scr != null && scr.initialized && scr.keyReleased(k)) {
+			if (scr != null && scr.initialized && scr.keyReleased(k)) {
 				refresh = true;
 			} else {
 				switch (k) {
@@ -760,26 +772,17 @@ public class Keyboard {
 				}
 			}
 			if (refresh) {
-				PIDisplay.display.repaint();
+//				PIDisplay.display.repaint();
 			}
 		}
 	}
 
 	public static enum Key {
-		POWER, debug_DEG, debug_RAD, debug_GRA, SHIFT, ALPHA, NONE,
+		POWER, debug_DEG, debug_RAD, debug_GRA, SHIFT, ALPHA, NONE, HISTORY_BACK, HISTORY_FORWARD, SURD_MODE, DRG_CYCLE, LETTER_X, LETTER_Y, SIMPLIFY, SOLVE, BRIGHTNESS_CYCLE, BRIGHTNESS_CYCLE_REVERSE, DOT, NUM0, NUM1, NUM2, NUM3, NUM4, NUM5, NUM6, NUM7, NUM8, NUM9, PARENTHESIS_OPEN, PARENTHESIS_CLOSE, PLUS, MINUS, PLUS_MINUS, MULTIPLY, DIVIDE, EQUAL, DELETE, RESET, LEFT, RIGHT, UP, DOWN, OK, debug1, debug2, debug3, debug4, debug5, SQRT, ROOT, POWER_OF_2, POWER_OF_x, SINE, COSINE, TANGENT, ARCSINE, ARCCOSINE, ARCTANGENT, PI
-		HISTORY_BACK, HISTORY_FORWARD, SURD_MODE, DRG_CYCLE,
-		LETTER_X, LETTER_Y, SIMPLIFY, SOLVE, BRIGHTNESS_CYCLE,
-		BRIGHTNESS_CYCLE_REVERSE, DOT, NUM0, NUM1, NUM2, NUM3, NUM4, NUM5, NUM6, NUM7, NUM8, NUM9,
-		PARENTHESIS_OPEN, PARENTHESIS_CLOSE, PLUS, MINUS, PLUS_MINUS, MULTIPLY, DIVIDE, EQUAL,
-		DELETE, RESET, LEFT, RIGHT, UP, DOWN, OK, debug1, debug2, debug3, debug4, debug5,
-		SQRT, ROOT, POWER_OF_2, POWER_OF_x,
-		SINE, COSINE, TANGENT, ARCSINE, ARCCOSINE, ARCTANGENT, PI
 	}
 
 }
 
-
-
 /*
 
 

src/org/warp/picalculator/device/chip/ParallelToSerial.java

@@ -4,10 +4,10 @@ import com.pi4j.wiringpi.Gpio;
 
 public class ParallelToSerial {
 
-	private int SH_LD;
+	private final int SH_LD;
-	private int CLK_INH;
+	private final int CLK_INH;
-	private int QH;
+	private final int QH;
-	private int CLK;
+	private final int CLK;
 
 	public ParallelToSerial(int SH_LD_pin, int CLK_INH_pin, int QH_pin, int CLK_pin) {
 		SH_LD = SH_LD_pin;
@@ -17,7 +17,7 @@ public class ParallelToSerial {
 	}
 
 	public boolean[] read() {
-		boolean[] data = new boolean[8];	
+		final boolean[] data = new boolean[8];
 		Gpio.digitalWrite(CLK_INH, Gpio.HIGH);
 		Gpio.digitalWrite(SH_LD, Gpio.LOW);
 		Gpio.delay(1);
@@ -27,7 +27,7 @@ public class ParallelToSerial {
 		for (int i = 7; i >= 0; i--) {
 			Gpio.digitalWrite(CLK, Gpio.HIGH);
 			Gpio.digitalWrite(CLK, Gpio.LOW);
-			data[i] = Gpio.digitalRead(QH)==Gpio.HIGH?true:false;
+			data[i] = Gpio.digitalRead(QH) == Gpio.HIGH ? true : false;
 		}
 
 		return data;

src/org/warp/picalculator/device/chip/SerialToParallel.java

@@ -3,9 +3,9 @@ package org.warp.picalculator.device.chip;
 import com.pi4j.wiringpi.Gpio;
 
 public class SerialToParallel {
-	private int RCK; //Storage register clock pin (latch pin)
+	private final int RCK; //Storage register clock pin (latch pin)
-	private int SCK; //Shift register clock pin
+	private final int SCK; //Shift register clock pin
-	private int SER; //Serial data input
+	private final int SER; //Serial data input
 
 	public SerialToParallel(int RCK_pin, int SCK_pin, int SER_pin) {
 		RCK = RCK_pin;

src/org/warp/picalculator/gui/DisplayManager.java

@@ -0,0 +1,494 @@
+package org.warp.picalculator.gui;
+
+import java.io.IOException;
+import java.lang.management.ManagementFactory;
+import java.lang.management.OperatingSystemMXBean;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.ArrayList;
+
+import org.warp.picalculator.Main;
+import org.warp.picalculator.Utils;
+import org.warp.picalculator.device.Keyboard;
+import org.warp.picalculator.gui.graphicengine.Display;
+import org.warp.picalculator.gui.graphicengine.Drawable;
+import org.warp.picalculator.gui.graphicengine.Renderer;
+import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
+import org.warp.picalculator.gui.graphicengine.gpu.GPUDisplay;
+import org.warp.picalculator.gui.graphicengine.RAWFont;
+import org.warp.picalculator.gui.graphicengine.RAWSkin;
+import org.warp.picalculator.gui.screens.Screen;
+
+import com.pi4j.wiringpi.Gpio;
+
+public final class DisplayManager implements Drawable {
+	public static DisplayManager INSTANCE;
+	private static float brightness;
+
+	public static final Display display = chooseGraphicEngine();
+	public static Renderer renderer;
+
+	private static RAWSkin skin;
+	public static RAWFont[] fonts;
+
+	public static String error = null;
+	public String[] errorStackTrace = null;
+	public final static int[] glyphsHeight = new int[] { 9, 6, 12, 9 };
+
+	public static Screen screen;
+	public static String displayDebugString = "";
+
+	public DisplayManager(Screen screen) {
+		setScreen(screen);
+		INSTANCE = this;
+		loop();
+	}
+	/*
+	 * private void load_skin() {
+	 * try {
+	 * skin_tex = glGenTextures();
+	 * glBindTexture(GL_TEXTURE_2D, skin_tex);
+	 * glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+	 * 
+	 * InputStream in = new FileInputStream("skin.png");
+	 * PNGDecoder decoder = new PNGDecoder(in);
+	 * 
+	 * System.out.println("width="+decoder.getWidth());
+	 * System.out.println("height="+decoder.getHeight());
+	 * 
+	 * ByteBuffer buf =
+	 * ByteBuffer.allocateDirect(4*decoder.getWidth()*decoder.getHeight());
+	 * decoder.decode(buf, decoder.getWidth()*4, Format.RGBA);
+	 * buf.flip();
+	 * 
+	 * skin = buf;
+	 * skin_w = decoder.getWidth();
+	 * skin_h = decoder.getHeight();
+	 * glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, skin_w,
+	 * skin_h, 0, GL_RGBA, GL_UNSIGNED_BYTE, skin);
+	 * } catch (IOException ex) {
+	 * ex.printStackTrace();
+	 * }
+	 * }
+	 */
+
+	private static Display chooseGraphicEngine() {
+		Display d;
+		d = new GPUDisplay();
+		if (d.isSupported()) return d;
+		d = new CPUDisplay();
+		if (d.isSupported()) return d;
+		throw new UnsupportedOperationException("No graphic engines available.");
+	}
+
+	public void setScreen(Screen screen) {
+		if (screen.initialized == false) {
+			if (screen.canBeInHistory) {
+				DisplayManager.currentSession = 0;
+				for (int i = DisplayManager.sessions.length - 1; i >= 1; i--) {
+					DisplayManager.sessions[i] = DisplayManager.sessions[i - 1];
+				}
+				DisplayManager.sessions[0] = screen;
+			} else {
+				DisplayManager.currentSession = -1;
+			}
+		}
+		screen.d = this;
+		try {
+			screen.create();
+			DisplayManager.screen = screen;
+			if (screen.initialized == false) {
+				screen.initialize();
+			}
+		} catch (final Exception e) {
+			e.printStackTrace();
+			System.exit(0);
+		}
+	}
+
+	public void replaceScreen(Screen screen) {
+		if (screen.initialized == false) {
+			if (screen.canBeInHistory) {
+				DisplayManager.sessions[DisplayManager.currentSession] = screen;
+			} else {
+				DisplayManager.currentSession = -1;
+				for (int i = 0; i < DisplayManager.sessions.length - 2; i++) {
+					DisplayManager.sessions[i] = DisplayManager.sessions[i + 1];
+				}
+			}
+		}
+		screen.d = this;
+		try {
+			screen.create();
+			DisplayManager.screen = screen;
+			if (screen.initialized == false) {
+				screen.initialize();
+			}
+		} catch (final Exception e) {
+			e.printStackTrace();
+			System.exit(0);
+		}
+	}
+
+	public boolean canGoBack() {
+		if (DisplayManager.currentSession == -1) {
+			return DisplayManager.sessions[0] != null;
+		}
+		if (DisplayManager.screen != DisplayManager.sessions[DisplayManager.currentSession]) {
+
+		} else if (DisplayManager.currentSession + 1 < DisplayManager.sessions.length) {
+			if (DisplayManager.sessions[DisplayManager.currentSession + 1] != null) {
+
+			} else {
+				return false;
+			}
+		} else {
+			return false;
+		}
+		if (DisplayManager.sessions[DisplayManager.currentSession] != null) {
+			return true;
+		}
+		return false;
+	}
+
+	public void goBack() {
+		if (canGoBack()) {
+			if (DisplayManager.currentSession >= 0 && DisplayManager.screen != DisplayManager.sessions[DisplayManager.currentSession]) {} else {
+				DisplayManager.currentSession += 1;
+			}
+			DisplayManager.screen = DisplayManager.sessions[DisplayManager.currentSession];
+		}
+	}
+
+	public boolean canGoForward() {
+		if (DisplayManager.currentSession <= 0) { // -1 e 0
+			return false;
+		}
+		if (DisplayManager.screen != DisplayManager.sessions[DisplayManager.currentSession]) {
+
+		} else if (DisplayManager.currentSession > 0) {
+			if (DisplayManager.sessions[DisplayManager.currentSession - 1] != null) {
+
+			} else {
+				return false;
+			}
+		} else {
+			return false;
+		}
+		if (DisplayManager.sessions[DisplayManager.currentSession] != null) {
+			return true;
+		}
+		return false;
+	}
+
+	public void goForward() {
+		if (canGoForward()) {
+			if (DisplayManager.screen != DisplayManager.sessions[DisplayManager.currentSession]) {
+
+			} else {
+				DisplayManager.currentSession -= 1;
+			}
+			DisplayManager.screen = DisplayManager.sessions[DisplayManager.currentSession];
+		}
+	}
+
+	public Screen getScreen() {
+		return DisplayManager.screen;
+	}
+
+	private void load_skin() throws IOException {
+		skin = display.loadSkin("skin.png");
+	}
+
+	private void load_fonts() throws IOException {
+		fonts = new RAWFont[7];
+		fonts[0] = display.loadFont("big");
+		fonts[1] = display.loadFont("small");
+		fonts[2] = display.loadFont("ex");
+		fonts[3] = display.loadFont("big");
+		fonts[4] = display.loadFont("32");
+		fonts[5] = display.loadFont("square");
+	}
+
+	private void draw_init() {
+		renderer.glClear(display.getWidth(), display.getHeight());
+	}
+
+	private void draw_status() {
+		renderer.glColor(0xFFc5c2af);
+		renderer.glFillColor(0, 0, display.getWidth(), 20);
+		renderer.glColor3i(0, 0, 0);
+		renderer.glDrawLine(0, 20, display.getWidth() - 1, 20);
+		renderer.glColor3i(255, 255, 255);
+		skin.use(display);
+		if (Keyboard.shift) {
+			renderer.glFillRect(2 + 18 * 0, 2, 16, 16, 16 * 2, 16 * 0, 16, 16);
+		} else {
+			renderer.glFillRect(2 + 18 * 0, 2, 16, 16, 16 * 3, 16 * 0, 16, 16);
+		}
+		if (Keyboard.alpha) {
+			renderer.glFillRect(2 + 18 * 1, 2, 16, 16, 16 * 0, 16 * 0, 16, 16);
+		} else {
+			renderer.glFillRect(2 + 18 * 1, 2, 16, 16, 16 * 1, 16 * 0, 16, 16);
+		}
+		/*
+		if (Calculator.angleMode == AngleMode.DEG) {
+			drawSkinPart(8 + 18 * 2, 2, 16 * 4, 16 * 0, 16 + 16 * 4, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 3, 2, 16 * 7, 16 * 0, 16 + 16 * 7, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 4, 2, 16 * 9, 16 * 0, 16 + 16 * 9, 16 + 16 * 0);
+		} else if (Calculator.angleMode == AngleMode.RAD) {
+			drawSkinPart(8 + 18 * 2, 2, 16 * 5, 16 * 0, 16 + 16 * 5, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 3, 2, 16 * 6, 16 * 0, 16 + 16 * 6, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 4, 2, 16 * 9, 16 * 0, 16 + 16 * 9, 16 + 16 * 0);
+		} else if (Calculator.angleMode == AngleMode.GRA) {
+			drawSkinPart(8 + 18 * 2, 2, 16 * 5, 16 * 0, 16 + 16 * 5, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 3, 2, 16 * 7, 16 * 0, 16 + 16 * 7, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 4, 2, 16 * 8, 16 * 0, 16 + 16 * 8, 16 + 16 * 0);
+		} else {
+			drawSkinPart(8 + 18 * 2, 2, 16 * 5, 16 * 0, 16 + 16 * 5, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 3, 2, 16 * 7, 16 * 0, 16 + 16 * 7, 16 + 16 * 0);
+			drawSkinPart(8 + 18 * 4, 2, 16 * 9, 16 * 0, 16 + 16 * 9, 16 + 16 * 0);
+		}*/
+
+		int padding = 2;
+
+		final int brightness = (int) (Math.ceil(DisplayManager.brightness * 9));
+		if (brightness <= 10) {
+			renderer.glFillRect(Main.screenSize[0] - (padding + 16), 2, 16, 16, 16 * brightness, 16 * 1, 16, 16);
+		} else {
+			Utils.debug.println("Brightness error");
+		}
+
+		padding += 18 + 6;
+
+		final boolean canGoBack = canGoBack();
+		final boolean canGoForward = canGoForward();
+
+		if (Main.haxMode) {
+			renderer.glFillRect(Main.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 18, 16 * 0, 16, 16);
+			padding += 18 + 6;
+		}
+
+		if (canGoBack && canGoForward) {
+			renderer.glFillRect(Main.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 14, 16 * 0, 16, 16);
+		} else if (canGoBack) {
+			renderer.glFillRect(Main.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 15, 16 * 0, 16, 16);
+		} else if (canGoForward) {
+			renderer.glFillRect(Main.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 16, 16 * 0, 16, 16);
+		} else {
+			renderer.glFillRect(Main.screenSize[0] - (padding + 16), 2, 16, 16, 16 * 17, 16 * 0, 16, 16);
+		}
+
+		padding += 18;
+
+		screen.renderStatusbar();
+	}
+
+	private void draw_screen() {
+		screen.render();
+	}
+
+	private void draw_bottom() {
+		renderer.glDrawStringLeft(2, 90, displayDebugString);
+
+		Utils.getFont(false, true).use(DisplayManager.display);
+		DisplayManager.renderer.glColor4i(255, 0, 0, 40);
+		DisplayManager.renderer.glDrawStringLeft(5 + 1, Main.screenSize[1] - 20 + 1, "WORK IN PROGRESS.");
+		DisplayManager.renderer.glColor4i(255, 0, 0, 80);
+		DisplayManager.renderer.glDrawStringLeft(5, Main.screenSize[1] - 20, "WORK IN PROGRESS.");
+	}
+
+	private void draw_world() {
+		renderer.glColor3i(255, 255, 255);
+
+		if (error != null) {
+			Utils.getFont(false, false).use(display);
+			renderer.glColor3i(129, 28, 22);
+			renderer.glDrawStringRight(Main.screenSize[0] - 2, Main.screenSize[1] - DisplayManager.glyphsHeight[1] - 2, "ANDREA CAVALLI'S CALCULATOR");
+			renderer.glColor3i(149, 32, 26);
+			renderer.glDrawStringCenter((Main.screenSize[0] / 2), 22, error);
+			renderer.glColor3i(164, 34, 28);
+			int i = 22;
+			for (final String stackPart : errorStackTrace) {
+				renderer.glDrawStringLeft(2, 22 + i, stackPart);
+				i += 11;
+			}
+			fonts[0].use(display);
+			renderer.glColor3i(129, 28, 22);
+			renderer.glDrawStringCenter((Main.screenSize[0] / 2), 11, "UNEXPECTED EXCEPTION");
+		} else {
+			fonts[0].use(display);
+			draw_screen();
+			draw_status();
+			draw_bottom();
+		}
+	}
+
+	private void draw() {
+		draw_init();
+		draw_world();
+	}
+
+	private long precTime = -1;
+
+	@Override
+	public void refresh() {
+		float dt = 0;
+		final long newtime = System.nanoTime();
+		if (precTime == -1) {
+			dt = 0;
+		} else {
+			dt = (float) ((newtime - precTime) / 1000000000d);
+		}
+		precTime = newtime;
+		/*
+		 * Calcoli
+		 */
+		checkDisplayResized();
+
+		screen.beforeRender(dt);
+
+		if (dt >= 0.03 || screen.mustBeRefreshed()) {
+			draw();
+		}
+
+	}
+
+	private void checkDisplayResized() {
+		if (display.wasResized()) {
+			Main.screenSize[0] = display.getWidth();
+			Main.screenSize[1] = display.getHeight();
+		}
+	};
+
+	public void loop() {
+		try {
+			load_skin();
+			load_fonts();
+			display.create();
+			renderer = display.getRenderer();
+
+			try {
+				screen.initialize();
+			} catch (final Exception e) {
+				e.printStackTrace();
+				System.exit(0);
+			}
+
+			//Debug thread
+			Thread dbgthrd = new Thread(() -> {
+				try {
+					while (true) {
+						for (int i = 0; i < 10; i++) {
+							System.out.println("============");
+							OperatingSystemMXBean operatingSystemMXBean = ManagementFactory.getOperatingSystemMXBean();
+							for (Method method : operatingSystemMXBean.getClass().getDeclaredMethods()) {
+								method.setAccessible(true);
+								if (method.getName().startsWith("get") && Modifier.isPublic(method.getModifiers())) {
+									Object value;
+									try {
+										value = method.invoke(operatingSystemMXBean);
+									} catch (Exception e) {
+										value = e;
+									} // try
+									boolean percent = false;
+									boolean mb = false;
+									String displayName = method.getName();
+									String displayValue = value.toString();
+									if (displayName.endsWith("CpuLoad")) {
+										percent = true;
+									}
+									if (displayName.endsWith("MemorySize")) {
+										mb = true;
+									}
+									ArrayList<String> arr = new ArrayList<>();
+									arr.add("getFreePhysicalMemorySize");
+									arr.add("getProcessCpuLoad");
+									arr.add("getSystemCpuLoad");
+									arr.add("getTotalPhysicalMemorySize");
+									if (arr.contains(displayName)) {
+										if (percent) {
+											try {
+												System.out.println(displayName + " = " + (((int)(Float.parseFloat(displayValue) * 10000f))/100f) + "%");
+											}catch(Exception ex) {
+												System.out.println(displayName + " = " + displayValue);
+											}
+										} else if (mb) {
+											try {
+												System.out.println(displayName + " = " + (Long.parseLong(displayValue) / 1024L / 1024L) + " MB");
+											}catch(Exception ex) {
+												System.out.println(displayName + " = " + displayValue);
+											}
+										} else {
+											System.out.println(displayName + " = " + displayValue);
+										}
+									}
+								} // if
+							} // for
+							System.out.println("============");
+							Thread.sleep(5000);
+						}
+					}
+				} catch (final InterruptedException e) {
+					// TODO Auto-generated catch block
+					e.printStackTrace();
+				}
+			});
+			dbgthrd.setDaemon(true);
+			dbgthrd.setName("Debug performance thread");
+			dbgthrd.start();
+			
+			display.start(this);
+			
+			display.waitUntilExit();
+		} catch (final Exception ex) {
+			ex.printStackTrace();
+		} finally {}
+	}
+
+	public static void changeBrightness(float change) {
+		setBrightness(brightness + change);
+	}
+
+	public static void setBrightness(float newval) {
+		if (newval >= 0 && newval <= 1) {
+			brightness = newval;
+			if (Utils.debugOn == false) {
+				Gpio.pwmWrite(12, (int) Math.ceil(brightness * 1024));
+//				SoftPwm.softPwmWrite(12, (int)(Math.ceil(brightness*10)));
+			}
+		}
+	}
+
+	public static void cycleBrightness(boolean reverse) {
+		final float step = reverse ? -0.1f : 0.1f;
+		if (brightness + step > 1f) {
+			setBrightness(0f);
+		} else if (brightness + step <= 0f) {
+			setBrightness(1.0f);
+		} else {
+			changeBrightness(step);
+		}
+	}
+
+	public static float getBrightness() {
+		return brightness;
+	}
+	
+	public static int currentSession = 0;
+	public static Screen[] sessions = new Screen[5];
+
+	@Deprecated
+	public static void colore(float f1, float f2, float f3, float f4) {
+		renderer.glColor4f(f1,f2,f3,f4);
+	}
+
+	public static Drawable getDrawable() {
+		return INSTANCE;
+	}
+
+	@Deprecated
+	public static void drawSkinPart(int x, int y, int uvX, int uvY, int uvX2, int uvY2) {
+		renderer.glFillRect(x, y, uvX2-uvX, uvY2-uvY, uvX, uvY, uvX2-uvX, uvY2-uvY);
+	}
+}

src/org/warp/picalculator/gui/GraphicUtils.java

@@ -0,0 +1,60 @@
+package org.warp.picalculator.gui;
+
+public class GraphicUtils {
+	   public static final float sin(float rad)
+	   {
+	      return sin[(int) (rad * radToIndex) & SIN_MASK];
+	   }
+
+	   public static final float cos(float rad)
+	   {
+	      return cos[(int) (rad * radToIndex) & SIN_MASK];
+	   }
+
+	   public static final float sinDeg(float deg)
+	   {
+	      return sin[(int) (deg * degToIndex) & SIN_MASK];
+	   }
+
+	   public static final float cosDeg(float deg)
+	   {
+	      return cos[(int) (deg * degToIndex) & SIN_MASK];
+	   }
+
+	   private static final float   RAD,DEG;
+	   private static final int     SIN_BITS,SIN_MASK,SIN_COUNT;
+	   private static final float   radFull,radToIndex;
+	   private static final float   degFull,degToIndex;
+	   private static final float[] sin, cos;
+
+	   static
+	   {
+	      RAD = (float) Math.PI / 180.0f;
+	      DEG = 180.0f / (float) Math.PI;
+
+	      SIN_BITS  = 12;
+	      SIN_MASK  = ~(-1 << SIN_BITS);
+	      SIN_COUNT = SIN_MASK + 1;
+
+	      radFull    = (float) (Math.PI * 2.0);
+	      degFull    = (float) (360.0);
+	      radToIndex = SIN_COUNT / radFull;
+	      degToIndex = SIN_COUNT / degFull;
+
+	      sin = new float[SIN_COUNT];
+	      cos = new float[SIN_COUNT];
+
+	      for (int i = 0; i < SIN_COUNT; i++)
+	      {
+	         sin[i] = (float) Math.sin((i + 0.5f) / SIN_COUNT * radFull);
+	         cos[i] = (float) Math.cos((i + 0.5f) / SIN_COUNT * radFull);
+	      }
+
+	      // Four cardinal directions (credits: Nate)
+	      for (int i = 0; i < 360; i += 90)
+	      {
+	         sin[(int)(i * degToIndex) & SIN_MASK] = (float)Math.sin(i * Math.PI / 180.0);
+	         cos[(int)(i * degToIndex) & SIN_MASK] = (float)Math.cos(i * Math.PI / 180.0);
+	      }
+	   }
+}

src/org/warp/picalculator/gui/PIDisplay.java

@@ -1,437 +0,0 @@
-package org.warp.picalculator.gui;
-
-import java.awt.image.BufferedImage;
-import java.io.IOException;
-
-import javax.imageio.ImageIO;
-
-import org.warp.picalculator.Main;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.device.Keyboard;
-import org.warp.picalculator.gui.graphicengine.Display;
-import org.warp.picalculator.gui.graphicengine.Drawable;
-import org.warp.picalculator.gui.graphicengine.RAWFont;
-import org.warp.picalculator.gui.graphicengine.Renderer;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
-import org.warp.picalculator.gui.screens.Screen;
-
-import com.pi4j.wiringpi.Gpio;
-
-public final class PIDisplay implements Drawable {
-	public static PIDisplay INSTANCE;
-	private static float brightness;
-	
-	public static final Display display = new CPUDisplay();
-	public static final Renderer renderer = display.getRenderer();
-
-	private static int[] skin;
-	private static int[] skinSize;
-	public static RAWFont[] fonts;
-
-	public static String error = null;
-	public String[] errorStackTrace = null;
-	public final static int[] glyphsHeight = new int[] { 9, 6, 12, 9 };
-
-	public static Screen screen;
-	public static String displayDebugString = "";
-
-	public PIDisplay(Screen screen) {
-		setScreen(screen);
-		INSTANCE = this;
-		loop();
-	}
-	/*
-	 * private void load_skin() {
-	 * try {
-	 * skin_tex = glGenTextures();
-	 * glBindTexture(GL_TEXTURE_2D, skin_tex);
-	 * glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-	 * 
-	 * InputStream in = new FileInputStream("skin.png");
-	 * PNGDecoder decoder = new PNGDecoder(in);
-	 * 
-	 * System.out.println("width="+decoder.getWidth());
-	 * System.out.println("height="+decoder.getHeight());
-	 * 
-	 * ByteBuffer buf =
-	 * ByteBuffer.allocateDirect(4*decoder.getWidth()*decoder.getHeight());
-	 * decoder.decode(buf, decoder.getWidth()*4, Format.RGBA);
-	 * buf.flip();
-	 * 
-	 * skin = buf;
-	 * skin_w = decoder.getWidth();
-	 * skin_h = decoder.getHeight();
-	 * glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, skin_w,
-	 * skin_h, 0, GL_RGBA, GL_UNSIGNED_BYTE, skin);
-	 * } catch (IOException ex) {
-	 * ex.printStackTrace();
-	 * }
-	 * }
-	 */
-
-	public void setScreen(Screen screen) {
-		if (screen.initialized == false) {
-			if (screen.canBeInHistory) {
-				PIDisplay.currentSession = 0;
-				for (int i = PIDisplay.sessions.length - 1; i >= 1; i--) {
-					PIDisplay.sessions[i] = PIDisplay.sessions[i - 1];
-				}
-				PIDisplay.sessions[0] = screen;
-			} else {
-				PIDisplay.currentSession = -1;
-			}
-		}
-		screen.d = this;
-		try {
-			screen.create();
-			PIDisplay.screen = screen;
-			if (screen.initialized == false) {
-				screen.initialize();
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-			System.exit(0);
-		}
-	}
-	
-	public void replaceScreen(Screen screen) {
-		if (screen.initialized == false) {
-			if (screen.canBeInHistory) {
-				PIDisplay.sessions[PIDisplay.currentSession] = screen;
-			} else {
-				PIDisplay.currentSession = -1;
-				for (int i = 0; i < PIDisplay.sessions.length - 2; i++) {
-					PIDisplay.sessions[i] = PIDisplay.sessions[i + 1];
-				}
-			}
-		}
-		screen.d = this;
-		try {
-			screen.create();
-			PIDisplay.screen = screen;
-			if (screen.initialized == false) {
-				screen.initialize();
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-			System.exit(0);
-		}
-	}
-
-	public boolean canGoBack() {
-		if (PIDisplay.currentSession == -1) {
-			return PIDisplay.sessions[0] != null;
-		}
-		if (PIDisplay.screen != PIDisplay.sessions[PIDisplay.currentSession]) {
-
-		} else if (PIDisplay.currentSession + 1 < PIDisplay.sessions.length) {
-			if (PIDisplay.sessions[PIDisplay.currentSession + 1] != null) {
-
-			} else {
-				return false;
-			}
-		} else {
-			return false;
-		}
-		if (PIDisplay.sessions[PIDisplay.currentSession] != null) {
-			return true;
-		}
-		return false;
-	}
-
-	public void goBack() {
-		if (canGoBack()) {
-			if (PIDisplay.currentSession >= 0 && PIDisplay.screen != PIDisplay.sessions[PIDisplay.currentSession]) {
-			} else {
-				PIDisplay.currentSession += 1;
-			}
-			PIDisplay.screen = PIDisplay.sessions[PIDisplay.currentSession];
-		}
-	}
-
-	public boolean canGoForward() {
-		if (PIDisplay.currentSession <= 0) { // -1 e 0
-			return false;
-		}
-		if (PIDisplay.screen != PIDisplay.sessions[PIDisplay.currentSession]) {
-
-		} else if (PIDisplay.currentSession > 0) {
-			if (PIDisplay.sessions[PIDisplay.currentSession - 1] != null) {
-
-			} else {
-				return false;
-			}
-		} else {
-			return false;
-		}
-		if (PIDisplay.sessions[PIDisplay.currentSession] != null) {
-			return true;
-		}
-		return false;
-	}
-
-	public void goForward() {
-		if (canGoForward()) {
-			if (PIDisplay.screen != PIDisplay.sessions[PIDisplay.currentSession]) {
-
-			} else {
-				PIDisplay.currentSession -= 1;
-			}
-			PIDisplay.screen = PIDisplay.sessions[PIDisplay.currentSession];
-		}
-	}
-
-	public Screen getScreen() {
-		return PIDisplay.screen;
-	}
-
-	private void load_skin() throws IOException {
-		BufferedImage img = ImageIO.read(Main.instance.getClass().getResource("/skin.png"));
-		skin = renderer.getMatrixOfImage(img);
-		skinSize = new int[] { img.getWidth(), img.getHeight() };
-	}
-
-	private void load_fonts() {
-		fonts = new RAWFont[7];
-		fonts[0] = new RAWFont();
-		fonts[0].create("big");
-		fonts[1] = new RAWFont();
-		fonts[1].create("small");
-		fonts[2] = new RAWFont();
-		fonts[2].create("ex");
-		fonts[3] = new RAWFont();
-		fonts[3].create("big");
-		fonts[4] = new RAWFont();
-		fonts[4].create("32");
-		fonts[5] = new RAWFont();
-		fonts[5].create("square");
-		renderer.glSetFont(fonts[0]);
-	}
-
-	private void draw_init() {
-		renderer.glClear();
-	}
-	
-	public static void drawSkinPart(int x, int y, int sx1, int sy1, int sx2, int sy2) {
-		renderer.glDrawSkin(skinSize[0], skin, x, y, sx1, sy1, sx2, sy2, false);
-	}
-
-	private void draw_status() {
-		renderer.glColor(0xFFc5c2af);
-		renderer.glFillRect(0, 0, Main.screenSize[0], 20);
-		renderer.glColor3i(0, 0, 0);
-		renderer.glDrawLine(0, 20, Main.screenSize[0]-1, 20);
-		renderer.glColor3i(0, 0, 0);
-		if (Keyboard.shift) {
-			drawSkinPart(2 + 18 * 0, 2, 16 * 2, 16 * 0, 16 + 16 * 2, 16 + 16 * 0);
-		} else {
-			drawSkinPart(2 + 18 * 0, 2, 16 * 3, 16 * 0, 16 + 16 * 3, 16 + 16 * 0);
-		}
-		if (Keyboard.alpha) {
-			drawSkinPart(2 + 18 * 1, 2, 16 * 0, 16 * 0, 16 + 16 * 0, 16 + 16 * 0);
-		} else {
-			drawSkinPart(2 + 18 * 1, 2, 16 * 1, 16 * 0, 16 + 16 * 1, 16 + 16 * 0);
-		}
-		/*
-		if (Calculator.angleMode == AngleMode.DEG) {
-			drawSkinPart(8 + 18 * 2, 2, 16 * 4, 16 * 0, 16 + 16 * 4, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 3, 2, 16 * 7, 16 * 0, 16 + 16 * 7, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 4, 2, 16 * 9, 16 * 0, 16 + 16 * 9, 16 + 16 * 0);
-		} else if (Calculator.angleMode == AngleMode.RAD) {
-			drawSkinPart(8 + 18 * 2, 2, 16 * 5, 16 * 0, 16 + 16 * 5, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 3, 2, 16 * 6, 16 * 0, 16 + 16 * 6, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 4, 2, 16 * 9, 16 * 0, 16 + 16 * 9, 16 + 16 * 0);
-		} else if (Calculator.angleMode == AngleMode.GRA) {
-			drawSkinPart(8 + 18 * 2, 2, 16 * 5, 16 * 0, 16 + 16 * 5, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 3, 2, 16 * 7, 16 * 0, 16 + 16 * 7, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 4, 2, 16 * 8, 16 * 0, 16 + 16 * 8, 16 + 16 * 0);
-		} else {
-			drawSkinPart(8 + 18 * 2, 2, 16 * 5, 16 * 0, 16 + 16 * 5, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 3, 2, 16 * 7, 16 * 0, 16 + 16 * 7, 16 + 16 * 0);
-			drawSkinPart(8 + 18 * 4, 2, 16 * 9, 16 * 0, 16 + 16 * 9, 16 + 16 * 0);
-		}*/
-
-		int padding = 2;
-
-		int brightness = (int) (Math.ceil(PIDisplay.brightness * 9));
-		if (brightness <= 10) {
-			drawSkinPart(Main.screenSize[0] - (padding + 16), 2, 16 * brightness, 16 * 1, 16 + 16 * brightness, 16 + 16 * 1);
-		} else {
-			Utils.debug.println("Brightness error");
-		}
-
-		padding += 18 + 6;
-
-		boolean canGoBack = canGoBack();
-		boolean canGoForward = canGoForward();
-
-		if (Main.haxMode) {
-			drawSkinPart(Main.screenSize[0] - (padding + 16), 2, 16 * 18, 16 * 0, 16 + 16 * 18, 16 + 16 * 0);
-			padding += 18 + 6;
-		}
-
-		if (canGoBack && canGoForward) {
-			drawSkinPart(Main.screenSize[0] - (padding + 16), 2, 16 * 14, 16 * 0, 16 + 16 * 14, 16 + 16 * 0);
-		} else if (canGoBack) {
-			drawSkinPart(Main.screenSize[0] - (padding + 16), 2, 16 * 15, 16 * 0, 16 + 16 * 15, 16 + 16 * 0);
-		} else if (canGoForward) {
-			drawSkinPart(Main.screenSize[0] - (padding + 16), 2, 16 * 16, 16 * 0, 16 + 16 * 16, 16 + 16 * 0);
-		} else {
-			drawSkinPart(Main.screenSize[0] - (padding + 16), 2, 16 * 17, 16 * 0, 16 + 16 * 17, 16 + 16 * 0);
-		}
-
-		padding += 18;
-
-		screen.renderStatusbar();
-	}
-
-	private void draw_screen() {
-		screen.render();
-	}
-
-	private void draw_bottom() {
-		renderer.glDrawStringLeft(2, 90, displayDebugString);
-	}
-
-	private void draw_world() {
-		renderer.glColor3i(255, 255, 255);
-
-		if (error != null) {
-			renderer.glSetFont(Utils.getFont(false, false));
-			renderer.glColor3i(129, 28, 22);
-			renderer.glDrawStringRight(Main.screenSize[0] - 2, Main.screenSize[1]- PIDisplay.glyphsHeight[1] - 2, "ANDREA CAVALLI'S CALCULATOR");
-			renderer.glColor3i(149, 32, 26);
-			renderer.glDrawStringCenter((Main.screenSize[0] / 2), 22, error);
-			renderer.glColor3i(164, 34, 28);
-			int i = 22;
-			for (String stackPart : errorStackTrace) {
-				renderer.glDrawStringLeft(2, 22 + i, stackPart);
-				i += 11;
-			}
-			renderer.glSetFont(fonts[0]);
-			renderer.glColor3i(129, 28, 22);
-			renderer.glDrawStringCenter((Main.screenSize[0] / 2), 11, "UNEXPECTED EXCEPTION");
-		} else {
-			draw_screen();
-			draw_status();
-			draw_bottom();
-		}
-	}
-
-	private void draw() {
-		draw_init();
-		draw_world();
-	}
-
-	private long precTime = -1;
-
-	@Override
-	public void refresh() {
-		float dt = 0;
-		long newtime = System.nanoTime();
-		if (precTime == -1) {
-			dt = 0;
-		} else {
-			dt = (float) ((newtime - precTime) / 1000000000d);
-		}
-		precTime = newtime;
-		/*
-		 * Calcoli
-		 */
-		checkDisplayResized();
-
-		screen.beforeRender(dt);
-		
-		if(dt >= 0.03 || screen.mustBeRefreshed()) {
-			draw();
-		}
-
-	}
-
-	private void checkDisplayResized() {
-		if (display.wasResized()) {
-			Main.screenSize[0] = display.getWidth();
-			Main.screenSize[1]= display.getHeight();
-		}
-	};
-	
-	public void loop() {
-		try {
-			load_skin();
-			load_fonts();
-			display.create();
-			
-			try {
-				screen.initialize();
-			} catch (Exception e) {
-				e.printStackTrace();
-				System.exit(0);
-			}
-
-			display.start(this);
-			
-			Main.instance.afterStart();
-
-			double extratime = 0;
-			while (CPUDisplay.initialized) {
-				long start = System.currentTimeMillis();
-				display.repaint();
-				long end = System.currentTimeMillis();
-				double delta = (end - start) / 1000d;
-				int deltaInt = (int) Math.floor(delta);
-				int extraTimeInt = (int) Math.floor(extratime);
-				if (extraTimeInt + deltaInt < 50) {
-					Thread.sleep(50 - (extraTimeInt + deltaInt));
-					extratime = 0;
-				} else {
-					extratime += delta - 50d;
-				}
-			}
-		} catch (Exception ex) {
-			ex.printStackTrace();
-		} finally {
-		}
-	}
-	
-	public static void changeBrightness(float change) {
-		setBrightness(brightness + change);
-	}
-
-	public static void setBrightness(float newval) {
-		if (newval >= 0 && newval <= 1) {
-			brightness = newval;
-			if (Utils.debugOn == false) {
-				Gpio.pwmWrite(12, (int) Math.ceil(brightness*1024));
-//				SoftPwm.softPwmWrite(12, (int)(Math.ceil(brightness*10)));
-			}
-		}
-	}
-
-	public static void cycleBrightness(boolean reverse) {
-		final float step = reverse?-0.1f:0.1f;
-		if (brightness + step > 1f) {
-			setBrightness(0f);
-		} else if (brightness + step <= 0f) {
-			setBrightness(1.0f);
-		} else {
-			changeBrightness(step);
-		}
-	}
-
-	public static float getBrightness() {
-		return brightness;
-	}
-
-	public float[] colore = new float[] { 0.0f, 0.0f, 0.0f, 1.0f };
-	public static int currentSession = 0;
-	public static Screen[] sessions = new Screen[5];
-	
-	public static void colore(float f1, float f2, float f3, float f4) {
-		PIDisplay.INSTANCE.colore = new float[] { f1, f2, f3, f4 };
-		renderer.glColor4i((int) (f1 * 255), (int) (f2 * 255), (int) (f3 * 255), (int) (f4 * 255));
-	}
-
-	public static Drawable getDrawable() {
-		return INSTANCE;
-	}
-}

src/org/warp/picalculator/gui/graphicengine/Display.java

@@ -1,6 +1,6 @@
 package org.warp.picalculator.gui.graphicengine;
 
-import java.awt.image.BufferedImage;
+import java.io.IOException;
 
 public interface Display {
 
@@ -29,4 +29,12 @@ public interface Display {
 	public void repaint();
 
 	public Renderer getRenderer();
+
+	public RAWFont loadFont(String file) throws IOException;
+
+	public RAWSkin loadSkin(String file) throws IOException;
+
+	public void waitUntilExit();
+
+	public boolean isSupported();
 }

src/org/warp/picalculator/gui/graphicengine/RAWFont.java

@@ -1,182 +1,14 @@
 package org.warp.picalculator.gui.graphicengine;
 
-import java.awt.image.BufferedImage;
-import java.awt.image.DataBufferInt;
-import java.io.File;
-import java.io.IOException;
-import java.lang.ref.WeakReference;
-import java.net.URL;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import javax.imageio.ImageIO;
-
-import org.warp.picalculator.Main;
-import org.warp.picalculator.Utils;
-
 /**
  *
  * @author andreacv
  */
-public class RAWFont {
+public interface RAWFont extends RAWSkin {
 
-    public boolean[][] rawchars;
+	public int getStringWidth(String text);
-    public int[] chars32;
-    public int minBound = 10;
-    public int maxBound = 0;
-    public int charW;
-    public int charH;
-    public int charS;
-    public int charIntCount;
-    public boolean installed;
-    public static final int intBits = 31;
 
-    public void create(String name) {
+	public int getCharacterWidth();
-    	try {
-			loadFont("/font_"+name+".rft");
-		} catch (IOException e) {
-			e.printStackTrace();
-			System.exit(1);
-		}
-        chars32 = new int[(maxBound-minBound)*charIntCount];
-        for (int charIndex = 0; charIndex < maxBound-minBound; charIndex++) {
-            boolean[] currentChar = rawchars[charIndex];
-            if (currentChar == null) {
-            	int currentInt = 0;
-            	int currentBit = 0;
-            	for (int i = 0; i < charS; i++) {
-            		if (currentInt*intBits+currentBit >= (currentInt+1)*intBits) {
-            			currentInt += 1;
-            			currentBit = 0;
-            		}
-            		chars32[charIndex*charIntCount+currentInt] = (chars32[charIndex*charIntCount+currentInt] << 1) + 1;
-        			currentBit += 1;
-            	}
-            } else {
-            	int currentInt = 0;
-            	int currentBit = 0;
-            	for (int i = 0; i < charS; i++) {
-            		if (currentBit >= intBits) {
-            			currentInt += 1;
-            			currentBit = 0;
-            		}
-            		chars32[charIndex*charIntCount+currentInt] = (chars32[charIndex*charIntCount+currentInt]) | ((currentChar[i] ? 1 : 0) << currentBit);
-            		currentBit++;
-            	}
-            }
-        }
 
-        Object obj = new Object();
+	public int getCharacterHeight();
-        WeakReference<Object> ref = new WeakReference<>(obj);
-        obj = null;
-        while (ref.get() != null) {
-            System.gc();
-        }
-    }
-
-	private void loadFont(String string) throws IOException {
-		URL res = Main.instance.getClass().getResource(string);
-		int[] file = Utils.realBytes(Utils.convertStreamToByteArray(res.openStream(), res.getFile().length()));
-		int filelength = file.length;
-		if (filelength >= 16) {
-			if (file[0x0] == 114 && file[0x1] == 97 && file[0x2] == 119 && file[0x3] == 0xFF && file[0x8] == 0xFF && file[0xD] == 0xFF) {
-				charW = file[0x4] << 8 | file[0x5];
-				charH = file[0x6] << 8 | file[0x7];
-				charS = charW*charH;
-				charIntCount = (int) Math.ceil(((double)charS)/((double)intBits));
-				minBound = file[0x9] << 24 | file[0xA] << 16 | file[0xB] << 8 | file[0xC];
-				maxBound = file[0xE] << 24 | file[0xF] << 16 | file[0x10] << 8 | file[0x11];
-				if (maxBound <= minBound) {
-					maxBound = 10000; //TODO remove it: temp fix
-				}
-		        rawchars = new boolean[maxBound-minBound][];
-		        int index = 0x12;
-		        while (index < filelength) {
-		        	try {
-			        	int charIndex = file[index] << 8 | file[index+1];
-			        	boolean[] rawchar = new boolean[charS];
-			        	int charbytescount = 0;
-			        	while (charbytescount*8 < charS) {
-			        		charbytescount+=1;
-			        	}
-			        	int currentBit = 0;
-			        	for (int i = 0; i <= charbytescount; i++) {
-			        		for (int bit = 0; bit < 8; bit++) {
-			        			if (currentBit >= charS) {
-			        				break;
-			        			}
-			        			rawchar[currentBit] = (((file[index + 2 + i] >> (8-1-bit)) & 0x1)==1)?true:false;
-			        			currentBit++;
-			        		}
-			        	}
-			        	rawchars[charIndex - minBound] = rawchar;
-			        	index += 2 + charbytescount;
-		        	}
-	        		catch (Exception ex) {
-	        			ex.printStackTrace();
-	        			System.out.println(string);
-	        			System.exit(-1);
-	        		}
-		        }
-			} else {
-				throw new IOException();
-			}
-		} else {
-			throw new IOException();
-		}
-	}
-
-	public int[] getCharIndexes(String txt) {
-        final int l = txt.length();
-        int[] indexes = new int[l];
-        char[] chars = txt.toCharArray();
-        for (int i = 0; i < l; i++) {
-            indexes[i] = (chars[i] & 0xFFFF)-minBound;
-        }
-        return indexes;
-    }
-
-    @SuppressWarnings("unused")
-	private void saveArray(int[] screen, String coutputpng) {
-        BufferedImage bi = new BufferedImage(300, 200, BufferedImage.TYPE_INT_RGB);
-        final int[] a = ((DataBufferInt) bi.getRaster().getDataBuffer()).getData();
-        System.arraycopy(screen, 0, a, 0, screen.length);
-        try {
-            ImageIO.write(bi, "PNG", new File(coutputpng));
-        } catch (IOException ex) {
-            Logger.getLogger(RAWFont.class.getName()).log(Level.SEVERE, null, ex);
-        }
-    }
-
-    public void drawText(int[] screen, int[] screenSize, int x, int y, int[] text, int color) {
-    	final int screenLength = screen.length;
-        int screenPos = 0;
-        
-        
-        int currentInt;
-        int currentIntBitPosition;
-        int bitData;
-        int cpos;
-        int j;
-        final int l = text.length;
-        for (int i = 0; i < l; i++) {
-        	cpos = (i * (charW + 1));
-            final int charIndex = text[i];
-            for (int dy = 0; dy < charH; dy++) {
-            	for (int dx = 0; dx < charW; dx++) {
-            		j = x + cpos + dx;
-            		if (j > 0 & j < screenSize[0]) {
-                        int bit = dx + dy * charW;
-                        currentInt = (int) (Math.floor(bit)/(intBits));
-                        currentIntBitPosition = bit-(currentInt*intBits);
-                        bitData = (chars32[charIndex*charIntCount+currentInt] >> currentIntBitPosition) & 1;
-                        screenPos = x + cpos + dx + (y + dy) * screenSize[0];
-                        if (bitData == 1 & screenLength > screenPos) {
-                            screen[screenPos] = color;
-                        }
-            		}
-                }
-            }
-        }
-    }
 }

src/org/warp/picalculator/gui/graphicengine/RAWSkin.java

@@ -0,0 +1,12 @@
+package org.warp.picalculator.gui.graphicengine;
+
+import java.io.IOException;
+
+public interface RAWSkin {
+
+	public void load(String file) throws IOException;
+
+	public void initialize(Display d);
+
+	public void use(Display d);
+}

src/org/warp/picalculator/gui/graphicengine/Renderer.java

@@ -1,31 +1,33 @@
 package org.warp.picalculator.gui.graphicengine;
 
 import java.awt.FontMetrics;
-import java.awt.image.BufferedImage;
 
 public interface Renderer {
 	public void glColor3i(int r, int gg, int b);
 
 	public void glColor(int c);
 
+	public void glColor4i(int red, int green, int blue, int alpha);
+
+	public void glColor3f(float red, float green, float blue);
+
+	public void glColor4f(float red, float green, float blue, float alpha);
+
+	public void glClearColor4i(int red, int green, int blue, int alpha);
+
+	public void glClearColor4f(float red, float green, float blue, float alpha);
+
 	public int glGetClearColor();
 
 	public void glClearColor(int c);
 
-	public void glColor4i(int red, int green, int blue, int alpha);
+	public void glClear(int screenWidth, int screenHeight);
-
-	public void glClearColor(int red, int green, int blue, int alpha);
-	
-	public void glClear();
-
-	public void glDrawSkin(int skinwidth, int[] skin, int x0, int y0, int s0, int t0, int s1, int t1, boolean transparent);
 
 	public void glDrawLine(int x0, int y0, int x1, int y1);
 
-	public void glFillRect(int x0, int y0, int w1, int h1);
+	public void glFillRect(int x, int y, int width, int height, float uvX, float uvY, float uvWidth, float uvHeight);
 
-	@Deprecated
+	public void glFillColor(int x, int y, int width, int height);
-	public int[] getMatrixOfImage(BufferedImage bufferedImage);
 
 	public void glDrawStringLeft(int x, int y, String text);
 
@@ -33,11 +35,7 @@ public interface Renderer {
 
 	public void glDrawStringRight(int x, int y, String text);
 	
-	public void glSetFont(RAWFont font);
+	public void glClearSkin();
-
-	public int glGetStringWidth(RAWFont rf, String text);
-
-	public int glGetFontWidth(FontMetrics fm, String text);
 
 	public RAWFont getCurrentFont();
 }

src/org/warp/picalculator/gui/graphicengine/cpu/CPUDisplay.java

@@ -1,35 +1,43 @@
 package org.warp.picalculator.gui.graphicengine.cpu;
 
 import java.awt.FontMetrics;
+import java.awt.GraphicsEnvironment;
 import java.awt.image.BufferedImage;
+import java.io.IOException;
 
 import org.warp.picalculator.Main;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.Display;
 import org.warp.picalculator.gui.graphicengine.Drawable;
 import org.warp.picalculator.gui.graphicengine.RAWFont;
+import org.warp.picalculator.gui.graphicengine.RAWSkin;
 import org.warp.picalculator.gui.graphicengine.Renderer;
 
 public class CPUDisplay implements Display {
 
-	private static SwingWindow INSTANCE;
+	private SwingWindow INSTANCE;
-	public static int[] size = new int[] { 1, 1 };
+	public int[] size = new int[] { 1, 1 };
-	public static BufferedImage g = new BufferedImage(size[0], size[1], BufferedImage.TYPE_INT_RGB);
+	public BufferedImage g = new BufferedImage(size[0], size[1], BufferedImage.TYPE_INT_RGB);
 	static int[] canvas2d = new int[1];
-	public static int color = 0xFF000000;
+	public int color = 0xFF000000;
-	public static boolean initialized = false;
+	public volatile boolean initialized = false;
+	private final CPURenderer r = new CPURenderer();
 
+	@Override
 	public void setTitle(String title) {
 		INSTANCE.setTitle(title);
 	}
 
+	@Override
 	public void setResizable(boolean r) {
 		INSTANCE.setResizable(r);
-		if (!r)
+		if (!r) {
 			INSTANCE.setUndecorated(true);
+		}
 	}
 
+	@Override
 	public void setDisplayMode(final int ww, final int wh) {
 		INSTANCE.setSize(ww, wh);
 		size = new int[] { ww, wh };
@@ -38,14 +46,16 @@ public class CPUDisplay implements Display {
 		INSTANCE.wasResized = false;
 	}
 
+	@Override
 	public void create() {
-		INSTANCE = new SwingWindow(PIDisplay.getDrawable());
+		INSTANCE = new SwingWindow(this, DisplayManager.getDrawable());
-		setResizable(Utils.debugOn&!Utils.debugThirdScreen);
+		setResizable(Utils.debugOn & !Utils.debugThirdScreen);
 		setDisplayMode(Main.screenSize[0], Main.screenSize[1]);
 		INSTANCE.setVisible(true);
 		initialized = true;
 	}
 
+	@Override
 	public boolean wasResized() {
 		if (INSTANCE.wasResized) {
 			size = new int[] { INSTANCE.getWidth(), INSTANCE.getHeight() };
@@ -57,37 +67,66 @@ public class CPUDisplay implements Display {
 		return false;
 	}
 
+	@Override
 	public int getWidth() {
-		return INSTANCE.getWidth()-Main.screenPos[0];
+		return INSTANCE.getWidth() - Main.screenPos[0];
 	}
 
+	@Override
 	public int getHeight() {
-		return INSTANCE.getHeight()-Main.screenPos[1];
+		return INSTANCE.getHeight() - Main.screenPos[1];
 	}
 
+	@Override
 	public void destroy() {
 		initialized = false;
 		INSTANCE.setVisible(false);
 		INSTANCE.dispose();
 	}
 
+	@Override
 	public void start(Drawable d) {
+		Thread th = new Thread(() -> {
+			try {
+				double extratime = 0;
+				while (initialized) {
+					final long start = System.currentTimeMillis();
+					repaint();
+					final long end = System.currentTimeMillis();
+					final double delta = (end - start) / 1000d;
+					final int deltaInt = (int) Math.floor(delta);
+					final int extraTimeInt = (int) Math.floor(extratime);
+					if (extraTimeInt + deltaInt < 50) {
+						Thread.sleep(50 - (extraTimeInt + deltaInt));
+						extratime = 0;
+					} else {
+						extratime += delta - 50d;
+					}
+				}
+			} catch (final InterruptedException e) {
+				e.printStackTrace();
+			}
+		});
+		th.setName("Game loop thread");
+		th.setDaemon(true);
+		th.start();
 	}
 
 	@Deprecated()
 	public void refresh() {
-		if (PIDisplay.screen == null || (PIDisplay.error != null && PIDisplay.error.length() > 0) || PIDisplay.screen == null || PIDisplay.screen.mustBeRefreshed()) {
+		if (DisplayManager.screen == null || (DisplayManager.error != null && DisplayManager.error.length() > 0) || DisplayManager.screen == null || DisplayManager.screen.mustBeRefreshed()) {
-			CPUDisplay.INSTANCE.c.repaint();
+			INSTANCE.c.repaint();
 		}
 	}
 
+	@Override
 	public void repaint() {
-		CPUDisplay.INSTANCE.c.repaint();
+		INSTANCE.c.repaint();
 	}
 
 	public abstract class Startable {
 		public Startable() {
-			this.force = false;
+			force = false;
 		}
 
 		public Startable(boolean force) {
@@ -99,58 +138,70 @@ public class CPUDisplay implements Display {
 		public abstract void run();
 	}
 
-	public class Render implements Renderer {
+	public class CPURenderer implements Renderer {
 		public int clearcolor = 0xFFc5c2af;
-		public RAWFont currentFont;
+		public CPUFont currentFont;
+		public CPUSkin currentSkin;
 
+		@Override
 		public void glColor3i(int r, int gg, int b) {
 			glColor4i(r, gg, b, 255);
 		}
 
+		@Override
 		public void glColor(int c) {
 			color = c & 0xFFFFFFFF;
 		}
 
+		@Override
 		public void glClearColor(int c) {
 			clearcolor = c & 0xFFFFFFFF;
 		}
 
+		@Override
 		public void glColor4i(int red, int green, int blue, int alpha) {
 			color = (alpha << 24) + (red << 16) + (green << 8) + (blue);
 		}
 
-		public void glClearColor(int red, int green, int blue, int alpha) {
+		@Override
+		public void glClearColor4i(int red, int green, int blue, int alpha) {
 			clearcolor = (alpha << 24) + (red << 16) + (green << 8) + (blue);
 		}
 
-		public void glClear() {
+		@Override
-			for (int x = 0; x < size[0]; x++) {
+		public void glClearColor4f(float red, float green, float blue, float alpha) {
-				for (int y = 0; y < size[1]; y++) {
+			clearcolor = ((int)(alpha*255) << 24) + ((int)(red*255) << 16) + ((int)(green*255) << 8) + ((int)(blue*255));
+		}
+
+		@Override
+		public void glClear(int screenWidth, int screenHeight) {
+			for (int x = 0; x < screenWidth; x++) {
+				for (int y = 0; y < screenHeight; y++) {
 					canvas2d[x + y * size[0]] = clearcolor;
 				}
 			}
 		}
 
-		public void glDrawSkin(int skinwidth, int[] skin, int x0, int y0, int s0, int t0, int s1, int t1, boolean transparent) {
+		private void glDrawSkin(int x0, int y0, int s0, int t0, int s1, int t1, boolean transparent) {
-			x0+=Main.screenPos[0];
+			x0 += Main.screenPos[0];
-			y0+=Main.screenPos[1];
+			y0 += Main.screenPos[1];
 			int oldColor;
 			int newColor;
-			int onex = s0 <= s1?1:-1;
+			final int onex = s0 <= s1 ? 1 : -1;
-			int oney = t0 <= t1?1:-1;
+			final int oney = t0 <= t1 ? 1 : -1;
 			int width = 0;
 			int height = 0;
 			if (onex == -1) {
-				int s00 = s0;
+				final int s00 = s0;
 				s0 = s1;
 				s1 = s00;
-				width = s1-s0;
+				width = s1 - s0;
 			}
 			if (oney == -1) {
-				int t00 = t0;
+				final int t00 = t0;
 				t0 = t1;
 				t1 = t00;
-				height = t1-t0;
+				height = t1 - t0;
 			}
 			if (x0 >= size[0] || y0 >= size[0]) {
 				return;
@@ -179,28 +230,35 @@ public class CPUDisplay implements Display {
 				}
 				y0 = 0;
 			}
+			int pixelX;
+			int pixelY;
 			for (int texx = 0; texx < s1 - s0; texx++) {
 				for (int texy = 0; texy < t1 - t0; texy++) {
-					newColor = skin[(s0 + texx) + (t0 + texy) * skinwidth];
+					pixelX = (x0 + texx * onex + width);
-					if (transparent) {
+					pixelY = (y0 + texy * oney + height);
-						oldColor = canvas2d[(x0 + texx*onex + width) + (y0 + texy*oney + height) * size[0]];
+					if (pixelX - (pixelX % size[0]) == 0) {
-						float a2 = (newColor >> 24 & 0xFF) / 255f;
+						newColor = currentSkin.skinData[(s0 + texx) + (t0 + texy) * currentSkin.skinSize[0]];
-						float a1 = 1f-a2;
+						if (transparent) {
-						int r = (int) ((oldColor >> 16 & 0xFF) * a1 + (newColor >> 16 & 0xFF) * a2);
+							oldColor = canvas2d[pixelX + pixelY * size[0]];
-						int g = (int) ((oldColor >> 8 & 0xFF) * a1 + (newColor >> 8 & 0xFF) * a2);
+							final float a2 = (newColor >> 24 & 0xFF) / 255f;
-						int b = (int) ((oldColor & 0xFF) * a1 + (newColor & 0xFF) * a2);
+							final float a1 = 1f - a2;
-						newColor = 0xFF000000 | r << 16 | g << 8 | b;
+							final int r = (int) ((oldColor >> 16 & 0xFF) * a1 + (newColor >> 16 & 0xFF) * a2);
+							final int g = (int) ((oldColor >> 8 & 0xFF) * a1 + (newColor >> 8 & 0xFF) * a2);
+							final int b = (int) ((oldColor & 0xFF) * a1 + (newColor & 0xFF) * a2);
+							newColor = 0xFF000000 | r << 16 | g << 8 | b;
+						}
+						canvas2d[pixelX + pixelY * size[0]] = newColor;
 					}
-					canvas2d[(x0 + texx*onex + width) + (y0 + texy*oney + height) * size[0]] = newColor;
 				}
 			}
 		}
 
+		@Override
 		public void glDrawLine(int x0, int y0, int x1, int y1) {
-			x0+=Main.screenPos[0];
+			x0 += Main.screenPos[0];
-			x1+=Main.screenPos[0];
+			x1 += Main.screenPos[0];
-			y0+=Main.screenPos[1];
+			y0 += Main.screenPos[1];
-			y1+=Main.screenPos[1];
+			y1 += Main.screenPos[1];
 			if (x0 >= size[0] || y0 >= size[0]) {
 				return;
 			}
@@ -213,7 +271,7 @@ public class CPUDisplay implements Display {
 					canvas2d[x0 + (y0 + y) * size[0]] = color;
 				}
 			} else {
-				int m = (y1 - y0) / (x1 - x0);
+				final int m = (y1 - y0) / (x1 - x0);
 				for (int texx = 0; texx <= x1 - x0; texx++) {
 					if (x0 + texx < size[0] && y0 + (m * texx) < size[1]) {
 						canvas2d[(x0 + texx) + (y0 + (m * texx)) * size[0]] = color;
@@ -222,12 +280,23 @@ public class CPUDisplay implements Display {
 			}
 		}
 
-		public void glFillRect(int x0, int y0, int w1, int h1) {
+		@Override
-			x0+=Main.screenPos[0];
+		public void glFillRect(int x, int y, int width, int height, float uvX, float uvY, float uvWidth,
-			y0+=Main.screenPos[1];
+				float uvHeight) {
-			int x1 = x0+w1;
+			if (currentSkin != null) {
-			int y1 = y0+h1;
+				glDrawSkin(x, y, (int) uvX, (int) uvY, (int) (uvWidth + uvX), (int) (uvHeight + uvY), true);
-			if (x0 >= size[0] || y0 >= size[0]) {
+			} else {
+				glFillColor(x, y, width, height);
+			}
+		}
+
+		@Override
+		public void glFillColor(int x, int y, int width, int height) {
+			x += Main.screenPos[0];
+			y += Main.screenPos[1];
+			int x1 = x + width;
+			int y1 = y + height;
+			if (x >= size[0] || y >= size[0]) {
 				return;
 			}
 			if (x1 >= size[0]) {
@@ -237,57 +306,62 @@ public class CPUDisplay implements Display {
 				y1 = size[1];
 			}
 			final int sizeW = size[0];
-			for (int x = x0; x < x1; x++) {
+			for (int px = x; px < x1; px++) {
-				for (int y = y0; y < y1; y++) {
+				for (int py = y; py < y1; py++) {
-					canvas2d[(x) + (y) * sizeW] = color;
+					canvas2d[(px) + (py) * sizeW] = color;
 				}
 			}
 		}
 
-		public int[] getMatrixOfImage(BufferedImage bufferedImage) {
+		@Override
-			int width = bufferedImage.getWidth(null);
+		public void glDrawStringLeft(int x, int y, String textString) {
-			int height = bufferedImage.getHeight(null);
+			x += Main.screenPos[0];
-			int[] pixels = new int[width * height];
+			y += Main.screenPos[1];
-			for (int i = 0; i < width; i++) {
+
-				for (int j = 0; j < height; j++) {
+			final int[] text = currentFont.getCharIndexes(textString);
-					pixels[i + j * width] = bufferedImage.getRGB(i, j);
+			final int[] screen = canvas2d;
+			final int[] screenSize = size;
+			final int screenLength = screen.length;
+			int screenPos = 0;
+
+			int currentInt;
+			int currentIntBitPosition;
+			int bitData;
+			int cpos;
+			int j;
+			final int l = text.length;
+			for (int i = 0; i < l; i++) {
+				cpos = (i * (currentFont.charW + 1));
+				final int charIndex = text[i];
+				for (int dy = 0; dy < currentFont.charH; dy++) {
+					for (int dx = 0; dx < currentFont.charW; dx++) {
+						j = x + cpos + dx;
+						if (j > 0 & j < screenSize[0]) {
+							final int bit = dx + dy * currentFont.charW;
+							currentInt = (int) (Math.floor(bit) / (CPUFont.intBits));
+							currentIntBitPosition = bit - (currentInt * CPUFont.intBits);
+							bitData = (currentFont.chars32[charIndex * currentFont.charIntCount + currentInt] >> currentIntBitPosition) & 1;
+							screenPos = x + cpos + dx + (y + dy) * screenSize[0];
+							if (bitData == 1 & screenLength > screenPos) {
+								screen[screenPos] = color;
+							}
+						}
+					}
 				}
 			}
-
-			return pixels;
-		}
-
-		public void glDrawStringLeft(int x, int y, String text) {
-			x+=Main.screenPos[0];
-			y+=Main.screenPos[1];
-			final int[] chars = currentFont.getCharIndexes(text);
-			currentFont.drawText(canvas2d, size, x, y, chars, color);
 		}
 
+		@Override
 		public void glDrawStringCenter(int x, int y, String text) {
-			glDrawStringLeft(x - (glGetStringWidth(currentFont, text) / 2), y, text);
+			glDrawStringLeft(x - (currentFont.getStringWidth(text) / 2), y, text);
 		}
 
+		@Override
 		public void glDrawStringRight(int x, int y, String text) {
-			glDrawStringLeft(x - glGetStringWidth(currentFont, text), y, text);
+			glDrawStringLeft(x - currentFont.getStringWidth(text), y, text);
-		}
-
-		public void glSetFont(RAWFont font) {
-			if (currentFont != font) {
-				currentFont = font;
-			}
-		}
-
-		public int glGetStringWidth(RAWFont rf, String text) {
-			int w =(rf.charW+1)*text.length();
-			if (text.length() > 0) {
-				return w-1;
-			} else {
-				return 0;
-			}
-			// return text.length()*6;
 		}
 
+		@Deprecated
 		public int glGetFontWidth(FontMetrics fm, String text) {
 			return fm.stringWidth(text);
 		}
@@ -307,6 +381,21 @@ public class CPUDisplay implements Display {
 			return currentFont;
 		}
 
+		@Override
+		public void glColor3f(float red, float green, float blue) {
+			glColor3i((int) (red * 255f), (int) (green * 255f), (int) (blue * 255f));
+		}
+
+		@Override
+		public void glColor4f(float red, float green, float blue, float alpha) {
+			glColor4i((int) (red * 255f), (int) (green * 255f), (int) (blue * 255f), (int) (alpha * 255f));
+		}
+
+		@Override
+		public void glClearSkin() {
+			currentSkin = null;
+		}
+
 	}
 
 	@Override
@@ -320,7 +409,33 @@ public class CPUDisplay implements Display {
 	}
 
 	@Override
-	public Renderer getRenderer() {
+	public CPURenderer getRenderer() {
-		return new Render();
+		return r;
+	}
+
+	@Override
+	public RAWFont loadFont(String file) throws IOException {
+		return new CPUFont(file);
+	}
+
+	@Override
+	public RAWSkin loadSkin(String file) throws IOException {
+		return new CPUSkin(file);
+	}
+
+	@Override
+	public void waitUntilExit() {
+		try {
+			do {
+				Thread.sleep(500);
+			} while(initialized);
+		} catch (InterruptedException e) {
+			
+		}
+	}
+
+	@Override
+	public boolean isSupported() {
+		return GraphicsEnvironment.isHeadless() == false;
 	}
 }

src/org/warp/picalculator/gui/graphicengine/cpu/CPUFont.java

@@ -0,0 +1,182 @@
+package org.warp.picalculator.gui.graphicengine.cpu;
+
+import java.awt.image.BufferedImage;
+import java.awt.image.DataBufferInt;
+import java.io.File;
+import java.io.IOException;
+import java.lang.ref.WeakReference;
+import java.net.URL;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.imageio.ImageIO;
+
+import org.warp.picalculator.Utils;
+import org.warp.picalculator.gui.graphicengine.Display;
+import org.warp.picalculator.gui.graphicengine.RAWFont;
+import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay.CPURenderer;
+
+public class CPUFont implements RAWFont {
+
+	public boolean[][] rawchars;
+	public int[] chars32;
+	public int minBound = 10;
+	public int maxBound = 0;
+	public int charW;
+	public int charH;
+	public int charS;
+	public int charIntCount;
+	public static final int intBits = 31;
+
+	CPUFont(String file) throws IOException {
+		load(file);
+	}
+
+	public static CPUFont loadTemporaryFont(String name) throws IOException {
+		return new CPUFont(name);
+	}
+
+	@Override
+	public void load(String name) throws IOException {
+		loadFont("/font_" + name + ".rft");
+		chars32 = new int[(maxBound - minBound) * charIntCount];
+		for (int charIndex = 0; charIndex < maxBound - minBound; charIndex++) {
+			final boolean[] currentChar = rawchars[charIndex];
+			if (currentChar == null) {
+				int currentInt = 0;
+				int currentBit = 0;
+				for (int i = 0; i < charS; i++) {
+					if (currentInt * intBits + currentBit >= (currentInt + 1) * intBits) {
+						currentInt += 1;
+						currentBit = 0;
+					}
+					chars32[charIndex * charIntCount + currentInt] = (chars32[charIndex * charIntCount + currentInt] << 1) + 1;
+					currentBit += 1;
+				}
+			} else {
+				int currentInt = 0;
+				int currentBit = 0;
+				for (int i = 0; i < charS; i++) {
+					if (currentBit >= intBits) {
+						currentInt += 1;
+						currentBit = 0;
+					}
+					chars32[charIndex * charIntCount + currentInt] = (chars32[charIndex * charIntCount + currentInt]) | ((currentChar[i] ? 1 : 0) << currentBit);
+					currentBit++;
+				}
+			}
+		}
+
+		Object obj = new Object();
+		final WeakReference<Object> ref = new WeakReference<>(obj);
+		obj = null;
+		while (ref.get() != null) {
+			System.gc();
+		}
+	}
+
+	private void loadFont(String string) throws IOException {
+		final URL res = this.getClass().getResource(string);
+		final int[] file = Utils.realBytes(Utils.convertStreamToByteArray(res.openStream(), res.getFile().length()));
+		final int filelength = file.length;
+		if (filelength >= 16) {
+			if (file[0x0] == 114 && file[0x1] == 97 && file[0x2] == 119 && file[0x3] == 0xFF && file[0x8] == 0xFF && file[0xD] == 0xFF) {
+				charW = file[0x4] << 8 | file[0x5];
+				charH = file[0x6] << 8 | file[0x7];
+				charS = charW * charH;
+				charIntCount = (int) Math.ceil(((double) charS) / ((double) intBits));
+				minBound = file[0x9] << 24 | file[0xA] << 16 | file[0xB] << 8 | file[0xC];
+				maxBound = file[0xE] << 24 | file[0xF] << 16 | file[0x10] << 8 | file[0x11];
+				if (maxBound <= minBound) {
+					maxBound = 9900; //TODO remove it: temp fix
+				}
+				rawchars = new boolean[maxBound - minBound][];
+				int index = 0x12;
+				while (index < filelength) {
+					try {
+						final int charIndex = file[index] << 8 | file[index + 1];
+						final boolean[] rawchar = new boolean[charS];
+						int charbytescount = 0;
+						while (charbytescount * 8 < charS) {
+							charbytescount += 1;
+						}
+						int currentBit = 0;
+						for (int i = 0; i <= charbytescount; i++) {
+							for (int bit = 0; bit < 8; bit++) {
+								if (currentBit >= charS) {
+									break;
+								}
+								rawchar[currentBit] = (((file[index + 2 + i] >> (8 - 1 - bit)) & 0x1) == 1) ? true : false;
+								currentBit++;
+							}
+						}
+						rawchars[charIndex - minBound] = rawchar;
+						index += 2 + charbytescount;
+					} catch (final Exception ex) {
+						ex.printStackTrace();
+						System.out.println(string);
+						System.exit(-1);
+					}
+				}
+			} else {
+				throw new IOException();
+			}
+		} else {
+			throw new IOException();
+		}
+	}
+
+	@SuppressWarnings("unused")
+	private void saveArray(int[] screen, String coutputpng) {
+		final BufferedImage bi = new BufferedImage(300, 200, BufferedImage.TYPE_INT_RGB);
+		final int[] a = ((DataBufferInt) bi.getRaster().getDataBuffer()).getData();
+		System.arraycopy(screen, 0, a, 0, screen.length);
+		try {
+			ImageIO.write(bi, "PNG", new File(coutputpng));
+		} catch (final IOException ex) {
+			Logger.getLogger(RAWFont.class.getName()).log(Level.SEVERE, null, ex);
+		}
+	}
+
+	public int[] getCharIndexes(String txt) {
+		final int l = txt.length();
+		final int[] indexes = new int[l];
+		final char[] chars = txt.toCharArray();
+		for (int i = 0; i < l; i++) {
+			indexes[i] = (chars[i] & 0xFFFF) - minBound;
+		}
+		return indexes;
+	}
+
+	@Override
+	public void initialize(Display d) {
+		// TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void use(Display d) {
+		((CPURenderer) d.getRenderer()).currentFont = this;
+	}
+
+	@Override
+	public int getStringWidth(String text) {
+		final int w = (charW + 1) * text.length();
+		if (text.length() > 0) {
+			return w - 1;
+		} else {
+			return 0;
+		}
+	}
+
+	@Override
+	public int getCharacterWidth() {
+		return charW;
+	}
+
+	@Override
+	public int getCharacterHeight() {
+		return charH;
+	}
+
+}

src/org/warp/picalculator/gui/graphicengine/cpu/CPUSkin.java

@@ -0,0 +1,53 @@
+package org.warp.picalculator.gui.graphicengine.cpu;
+
+import java.awt.image.BufferedImage;
+import java.io.IOException;
+
+import javax.imageio.ImageIO;
+
+import org.warp.picalculator.Main;
+import org.warp.picalculator.gui.graphicengine.Display;
+import org.warp.picalculator.gui.graphicengine.RAWSkin;
+import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay.CPURenderer;
+
+public class CPUSkin implements RAWSkin {
+
+	public int[] skinData;
+	public int[] skinSize;
+
+	CPUSkin(String file) throws IOException {
+		load(file);
+	}
+
+	@Override
+	public void load(String file) throws IOException {
+		final BufferedImage img = ImageIO.read(Main.instance.getClass().getResource("/"+file));
+		skinData = getMatrixOfImage(img);
+		skinSize = new int[] { img.getWidth(), img.getHeight() };
+	}
+
+	public static int[] getMatrixOfImage(BufferedImage bufferedImage) {
+		final int width = bufferedImage.getWidth(null);
+		final int height = bufferedImage.getHeight(null);
+		final int[] pixels = new int[width * height];
+		for (int i = 0; i < width; i++) {
+			for (int j = 0; j < height; j++) {
+				pixels[i + j * width] = bufferedImage.getRGB(i, j);
+			}
+		}
+
+		return pixels;
+	}
+
+	@Override
+	public void initialize(Display d) {
+		// TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void use(Display d) {
+		((CPURenderer) d.getRenderer()).currentSkin = this;
+	}
+
+}

src/org/warp/picalculator/gui/graphicengine/cpu/SwingWindow.java

@@ -18,7 +18,7 @@ import javax.swing.JPanel;
 import org.warp.picalculator.Utils;
 import org.warp.picalculator.device.Keyboard;
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.Drawable;
 
 public class SwingWindow extends JFrame {
@@ -26,40 +26,41 @@ public class SwingWindow extends JFrame {
 	public CustomCanvas c;
 	private static Drawable d;
 	public boolean wasResized = false;
+	private final CPUDisplay display;
 
-	public SwingWindow(Drawable d) {
+	public SwingWindow(CPUDisplay disp, Drawable d) {
 		SwingWindow.d = d;
+		display = disp;
 		c = new CustomCanvas();
 		c.setDoubleBuffered(false);
 		this.add(c);
 //		this.setExtendedState(Frame.MAXIMIZED_BOTH);
 		Toolkit.getDefaultToolkit().setDynamicLayout(false);
 		// Transparent 16 x 16 pixel cursor image.
-		BufferedImage cursorImg = new BufferedImage(16, 16, BufferedImage.TYPE_INT_ARGB);
+		final BufferedImage cursorImg = new BufferedImage(16, 16, BufferedImage.TYPE_INT_ARGB);
 
 		if (Utils.debugOn) {
 			if (Utils.debugThirdScreen) {
 				this.setLocation(2880, 900);
-				this.setResizable(false);
+				setResizable(false);
-				this.setAlwaysOnTop(true);
+				setAlwaysOnTop(true);
 			}
 		} else {
 			// Create a new blank cursor.
-			Cursor blankCursor = Toolkit.getDefaultToolkit().createCustomCursor(cursorImg, new Point(0, 0), "blank cursor");
+			final Cursor blankCursor = Toolkit.getDefaultToolkit().createCustomCursor(cursorImg, new Point(0, 0), "blank cursor");
 
 			// Set the blank cursor to the JFrame.
 			getContentPane().setCursor(blankCursor);
 
-			this.setResizable(false);
+			setResizable(false);
 		}
 
-		this.setTitle("Raspberry PI Calculator by XDrake99 (Andrea Cavalli)");
+		setTitle("Raspberry PI Calculator by XDrake99 (Andrea Cavalli)");
 
-		
+		addComponentListener(new ComponentListener() {
-		this.addComponentListener(new ComponentListener() {
 			@Override
 			public void componentHidden(ComponentEvent e) {
-				PIDisplay.display.destroy();
+				DisplayManager.display.destroy();
 			}
 
 			@Override
@@ -73,10 +74,10 @@ public class SwingWindow extends JFrame {
 			@Override
 			public void componentShown(ComponentEvent e) {}
 		});
-		this.addKeyListener(new KeyListener() {
+		addKeyListener(new KeyListener() {
 			@Override
 			public void keyPressed(KeyEvent arg0) {
-				Keyboard.debugKeyEvent = arg0;
+				Keyboard.debugKeyCode = arg0.getKeyCode();
 			}
 
 			@Override
@@ -125,7 +126,7 @@ public class SwingWindow extends JFrame {
 						}
 						int row = 2;
 						int col = 1;
-						Keyboard.debugKeysDown[row-1][col-1] = false;
+						Keyboard.debugKeysDown[row - 1][col - 1] = false;
 						break;
 					case KeyEvent.VK_1:
 						if (!Keyboard.shift && !Keyboard.alpha) {
@@ -175,12 +176,12 @@ public class SwingWindow extends JFrame {
 						//LEFT
 						row = 2;
 						col = 3;
-						Keyboard.debugKeysDown[row-1][col-1] = false;
+						Keyboard.debugKeysDown[row - 1][col - 1] = false;
 					case KeyEvent.VK_RIGHT:
 						//RIGHT
 						row = 2;
 						col = 5;
-						Keyboard.debugKeysDown[row-1][col-1] = false;
+						Keyboard.debugKeysDown[row - 1][col - 1] = false;
 				}
 			}
 
@@ -216,7 +217,7 @@ public class SwingWindow extends JFrame {
 
 //	private static ArrayList<Double> mediaValori = new ArrayList<Double>();
 
-	public static class CustomCanvas extends JPanel {
+	public class CustomCanvas extends JPanel {
 
 		/**
 		 * 
@@ -228,11 +229,11 @@ public class SwingWindow extends JFrame {
 //			long time1 = System.nanoTime();
 			d.refresh();
 
-	        final int[] a = ((DataBufferInt) CPUDisplay.g.getRaster().getDataBuffer()).getData();
+			final int[] a = ((DataBufferInt) display.g.getRaster().getDataBuffer()).getData();
 //		        System.arraycopy(canvas2d, 0, a, 0, canvas2d.length);
-	        CPUDisplay.canvas2d = a;
+			CPUDisplay.canvas2d = a;
-			g.clearRect(0, 0, CPUDisplay.size[0], CPUDisplay.size[1]);
+			g.clearRect(0, 0, display.size[0], display.size[1]);
-			g.drawImage(CPUDisplay.g, 0, 0, null);
+			g.drawImage(display.g, 0, 0, null);
 //			long time2 = System.nanoTime();
 //			double timeDelta = ((double)(time2-time1))/1000000000d;
 //			double mediaAttuale = timeDelta;

src/org/warp/picalculator/gui/graphicengine/gpu/CalculatorWindow.java

@@ -1,673 +0,0 @@
-/**
- * Copyright 2012-2013 JogAmp Community. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without modification, are
- * permitted provided that the following conditions are met:
- *
- *    1. Redistributions of source code must retain the above copyright notice, this list of
- *       conditions and the following disclaimer.
- *
- *    2. Redistributions in binary form must reproduce the above copyright notice, this list
- *       of conditions and the following disclaimer in the documentation and/or other materials
- *       provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
- * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- * The views and conclusions contained in the software and documentation are those of the
- * authors and should not be interpreted as representing official policies, either expressed
- * or implied, of JogAmp Community.
- */
-
-package org.warp.picalculator.gui.graphicengine.gpu;
-
-import com.jogamp.opengl.GL;
-import com.jogamp.opengl.GL2ES1;
-import com.jogamp.opengl.GL2ES2;
-import com.jogamp.opengl.GLAutoDrawable;
-import com.jogamp.opengl.GLEventListener;
-import com.jogamp.opengl.GLException;
-import com.jogamp.opengl.GLProfile;
-import com.jogamp.opengl.GLCapabilities;
-import com.jogamp.newt.opengl.GLWindow;
-
-import com.jogamp.opengl.util.*;
-import com.jogamp.opengl.util.texture.Texture;
-import com.jogamp.opengl.util.texture.TextureIO;
-import com.jogamp.common.nio.Buffers;
-
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
-import java.io.File;
-import java.io.IOException;
-import java.io.InputStream;
-import java.nio.FloatBuffer;
-
-import javax.imageio.ImageIO;
-
-import org.warp.picalculator.gui.graphicengine.Display;
-
-/**
- * <pre>
- *   __ __|_  ___________________________________________________________________________  ___|__ __
- *  //    /\                                           _                                  /\    \\
- * //____/  \__     __ _____ _____ _____ _____ _____  | |     __ _____ _____ __        __/  \____\\
- *  \    \  / /  __|  |     |   __|  _  |     |  _  | | |  __|  |     |   __|  |      /\ \  /    /
- *   \____\/_/  |  |  |  |  |  |  |     | | | |   __| | | |  |  |  |  |  |  |  |__   "  \_\/____/
- *  /\    \     |_____|_____|_____|__|__|_|_|_|__|    | | |_____|_____|_____|_____|  _  /    /\
- * /  \____\                       http://jogamp.org  |_|                              /____/  \
- * \  /   "' _________________________________________________________________________ `"   \  /
- *  \/____.                                                                             .____\/
- * </pre>
- *
- * <p>
- * JOGL2 OpenGL ES 2 demo to expose and learn what the RAW OpenGL ES 2 API looks like.
- *
- * Compile, run and enjoy:
-   wget http://jogamp.org/deployment/jogamp-current/archive/jogamp-all-platforms.7z
-   7z x jogamp-all-platforms.7z
-   cd jogamp-all-platforms
-   mkdir -p demos/es2
-   cd demos/es2
-   wget https://raw.github.com/xranby/jogl-demos/master/src/demos/es2/RawGL2ES2demo.java
-   cd ../..
-   javac -cp jar/jogl-all.jar:jar/gluegen-rt.jar demos/es2/RawGL2ES2demo.java
-   java -cp jar/jogl-all.jar:jar/gluegen-rt.jar:. demos.es2.RawGL2ES2demo
- * </p>
- *
- *
- * @author Xerxes Rånby (xranby)
- */
-
-public class CalculatorWindow implements GLEventListener{
-
-/* Introducing the OpenGL ES 2 Vertex shader
- *
- * The main loop inside the vertex shader gets executed
- * one time for each vertex.
- *
- *      vertex -> *       uniform data -> mat4 projection = ( 1, 0, 0, 0,
- *      (0,1,0)  / \                                          0, 1, 0, 0,
- *              / . \  <- origo (0,0,0)                       0, 0, 1, 0,
- *             /     \                                        0, 0,-1, 1 );
- *  vertex -> *-------* <- vertex
- *  (-1,-1,0)             (1,-1,0) <- attribute data can be used
- *                        (0, 0,1)    for color, position, normals etc.
- *
- * The vertex shader recive input data in form of
- * "uniform" data that are common to all vertex
- * and
- * "attribute" data that are individual to each vertex.
- * One vertex can have several "attribute" data sources enabled.
- *
- * The vertex shader produce output used by the fragment shader.
- * gl_Position are expected to get set to the final vertex position.
- * You can also send additional user defined
- * "varying" data to the fragment shader.
- *
- * Model Translate, Scale and Rotate are done here by matrix-multiplying a
- * projection matrix against each vertex position.
- *
- * The whole vertex shader program are a String containing GLSL ES language
- * http://www.khronos.org/registry/gles/specs/2.0/GLSL_ES_Specification_1.0.17.pdf
- * sent to the GPU driver for compilation.
- */
-private String vertexShaderString =
-// For GLSL 1 and 1.1 code i highly recomend to not include a
-// GLSL ES language #version line, GLSL ES section 3.4
-// Many GPU drivers refuse to compile the shader if #version is different from
-// the drivers internal GLSL version.
-//
-// This demo use GLSL version 1.1 (the implicit version)
-
-"#if __VERSION__ >= 130\n" + // GLSL 130+ uses in and out
-"  #define attribute in\n" + // instead of attribute and varying
-"  #define varying out\n" +  // used by OpenGL 3 core and later.
-"#endif\n" +
-
-"#ifdef GL_ES \n" +
-"precision mediump float; \n" + // Precision Qualifiers
-"precision mediump int; \n" +   // GLSL ES section 4.5.2
-"#endif \n" +
-
-"uniform mat4    uniform_Projection; \n" + // Incomming data used by
-"attribute vec4  attribute_Position; \n" + // the vertex shader
-"attribute vec4  attribute_Color; \n" +    // uniform and attributes
-"attribute vec2  a_TexCoordinate; \n" +
-
-"varying vec2    v_TexCoordinate; \n" +
-"varying vec4    varying_Color; \n" + // Outgoing varying data
-                                      // sent to the fragment shader
-"void main(void) \n" +
-"{ \n" +
-"  varying_Color = attribute_Color; \n" +
-"  v_TexCoordinate = a_TexCoordinate; \n" +
-"  gl_Position = uniform_Projection * attribute_Position; \n" +
-"} ";
-
-/* Introducing the OpenGL ES 2 Fragment shader
- *
- * The main loop of the fragment shader gets executed for each visible
- * pixel fragment on the render buffer.
- *
- *       vertex-> *
- *      (0,1,-1) /f\
- *              /ffF\ <- This fragment F gl_FragCoord get interpolated
- *             /fffff\                   to (0.25,0.25,-1) based on the
- *   vertex-> *fffffff* <-vertex         three vertex gl_Position.
- *  (-1,-1,-1)           (1,-1,-1)
- *
- *
- * All incomming "varying" and gl_FragCoord data to the fragment shader
- * gets interpolated based on the vertex positions.
- *
- * The fragment shader produce and store the final color data output into
- * gl_FragColor.
- *
- * Is up to you to set the final colors and calculate lightning here based on
- * supplied position, color and normal data.
- *
- * The whole fragment shader program are a String containing GLSL ES language
- * http://www.khronos.org/registry/gles/specs/2.0/GLSL_ES_Specification_1.0.17.pdf
- * sent to the GPU driver for compilation.
- */
-private String fragmentShaderString =
-"#if __VERSION__ >= 130\n" +
-"  #define varying in\n" +
-"  out vec4 mgl_FragColor;\n" +
-"  #define texture2D texture\n" +
-"  #define gl_FragColor mgl_FragColor\n" +
-"#endif\n" +
-
-"#ifdef GL_ES \n" +
-"precision mediump float; \n" +
-"precision mediump int; \n" +
-"#endif \n" +
-
-"uniform sampler2D u_Texture; \n" +
-
-"varying   vec2    v_TexCoordinate; \n" +
-"varying   vec4    varying_Color; \n" + //incomming varying data to the
-                                        //frament shader
-                                        //sent from the vertex shader
-"void main (void) \n" +
-"{ \n" +
-
-"  gl_FragColor = (varying_Color * texture2D(u_Texture, v_TexCoordinate));" +
-"} ";
-
-
-FloatBuffer fbVertices = Buffers.newDirectFloatBuffer(2000*18); // max 2000 quadrati
-FloatBuffer fbColors = Buffers.newDirectFloatBuffer(2000*24); // max 2000 quadrati
-FloatBuffer fbTextureCoordinates = Buffers.newDirectFloatBuffer(2000*12); // max 2000 quadrati
-final Texture[] texture = new Texture[1];
-final int[] textureHandle = new int[1];
-
-private final Display disp;
-public CalculatorWindow(Display disp) {
-	this.disp = disp;
-}
-
-	/* Introducing projection matrix helper functions
- *
- * OpenGL ES 2 vertex projection transformations gets applied inside the
- * vertex shader, all you have to do are to calculate and supply a projection matrix.
- *
- * Its recomended to use the com/jogamp/opengl/util/PMVMatrix.java
- * import com.jogamp.opengl.util.PMVMatrix;
- * To simplify all your projection model view matrix creation needs.
- *
- * These helpers here are based on PMVMatrix code and common linear
- * algebra for matrix multiplication, translate and rotations.
- */
-    private void glMultMatrixf(FloatBuffer a, FloatBuffer b, FloatBuffer d) {
-        final int aP = a.position();
-        final int bP = b.position();
-        final int dP = d.position();
-        for (int i = 0; i < 4; i++) {
-            final float ai0=a.get(aP+i+0*4),  ai1=a.get(aP+i+1*4),  ai2=a.get(aP+i+2*4),  ai3=a.get(aP+i+3*4);
-            d.put(dP+i+0*4 , ai0 * b.get(bP+0+0*4) + ai1 * b.get(bP+1+0*4) + ai2 * b.get(bP+2+0*4) + ai3 * b.get(bP+3+0*4) );
-            d.put(dP+i+1*4 , ai0 * b.get(bP+0+1*4) + ai1 * b.get(bP+1+1*4) + ai2 * b.get(bP+2+1*4) + ai3 * b.get(bP+3+1*4) );
-            d.put(dP+i+2*4 , ai0 * b.get(bP+0+2*4) + ai1 * b.get(bP+1+2*4) + ai2 * b.get(bP+2+2*4) + ai3 * b.get(bP+3+2*4) );
-            d.put(dP+i+3*4 , ai0 * b.get(bP+0+3*4) + ai1 * b.get(bP+1+3*4) + ai2 * b.get(bP+2+3*4) + ai3 * b.get(bP+3+3*4) );
-        }
-    }
-
-    private float[] multiply(float[] a,float[] b){
-        float[] tmp = new float[16];
-        glMultMatrixf(FloatBuffer.wrap(a),FloatBuffer.wrap(b),FloatBuffer.wrap(tmp));
-        return tmp;
-    }
-
-    private float[] translate(float[] m,float x,float y,float z){
-        float[] t = { 1.0f, 0.0f, 0.0f, 0.0f,
-                      0.0f, 1.0f, 0.0f, 0.0f,
-                      0.0f, 0.0f, 1.0f, 0.0f,
-                      x, y, z, 1.0f };
-        return multiply(m, t);
-    }
-
-    private float[] rotate(float[] m,float a,float x,float y,float z){
-        float s, c;
-        s = (float)Math.sin(Math.toRadians(a));
-        c = (float)Math.cos(Math.toRadians(a));
-        float[] r = {
-            x * x * (1.0f - c) + c,     y * x * (1.0f - c) + z * s, x * z * (1.0f - c) - y * s, 0.0f,
-            x * y * (1.0f - c) - z * s, y * y * (1.0f - c) + c,     y * z * (1.0f - c) + x * s, 0.0f,
-            x * z * (1.0f - c) + y * s, y * z * (1.0f - c) - x * s, z * z * (1.0f - c) + c,     0.0f,
-            0.0f, 0.0f, 0.0f, 1.0f };
-            return multiply(m, r);
-        }
-
-/* Introducing the GL2ES2 demo
- *
- * How to render a triangle using ~500 lines of code using the RAW
- * OpenGL ES 2 API.
- * The Programmable pipeline in OpenGL ES 2 are both fast and flexible
- * yet it do take some extra lines of code to setup.
- *
- */
-    private double t0 = System.currentTimeMillis();
-    private double theta;
-    private double s;
-
-    private static int width=1920;
-    private static int height=1080;
-
-    private int shaderProgram;
-    private int vertShader;
-    private int fragShader;
-    private int ModelViewProjectionMatrixHandle;
-    private int mTextureUniformHandle;
-    private int mTextureCoordinateHandle;
-    private final int mTextureCoordinateDataSize = 2;
-    private int mTextureDataHandle;
-    static final int COLOR_IDX = 0;
-    static final int VERTICES_IDX = 1;
-    static final int TEXTURE_IDX = 2;
-    int[] vboHandles;
-
-    public GLWindow window;
-    
-    public void create(){
-        /* This demo are based on the GL2ES2 GLProfile that uses common hardware acceleration
-         * functionality of desktop OpenGL 3, 2 and mobile OpenGL ES 2 devices.
-         * JogAmp JOGL will probe all the installed libGL.so, libEGL.so and libGLESv2.so librarys on
-         * the system to find which one provide hardware acceleration for your GPU device.
-         * Its common to find more than one version of these librarys installed on a system.
-         * For example on a ARM Linux system JOGL may find
-         * Hardware accelerated Nvidia tegra GPU drivers in: /usr/lib/nvidia-tegra/libEGL.so
-         * Software rendered Mesa Gallium driver in: /usr/lib/arm-linux-gnueabi/mesa-egl/libEGL.so.1
-         * Software rendered Mesa X11 in: /usr/lib/arm-linux-gnueabi/mesa/libGL.so
-         * Good news!: JOGL does all this probing for you all you have to do are to ask for
-         * the GLProfile you want to use.
-         */
-
-        GLCapabilities caps = new GLCapabilities(GLProfile.get(GLProfile.GL2ES2));
-        // We may at this point tweak the caps and request a translucent drawable
-        caps.setBackgroundOpaque(false);
-        GLWindow glWindow = GLWindow.create(caps);
-        window = glWindow;
-
-        /* You may combine the NEWT GLWindow inside existing Swing and AWT
-         * applications by encapsulating the glWindow inside a
-         * com.jogamp.newt.awt.NewtCanvasAWT canvas.
-         *
-         *  NewtCanvasAWT newtCanvas = new NewtCanvasAWT(glWindow);
-         *  JFrame frame = new JFrame("RAW GL2ES2 Demo inside a JFrame!");
-         *  frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
-         *  frame.setSize(width,height);
-         *  frame.add(newtCanvas);
-         *  // add some swing code if you like.
-         *  // javax.swing.JButton b = new javax.swing.JButton();
-         *  // b.setText("Hi");
-         *  // frame.add(b);
-         *  frame.setVisible(true);
-         */
-
-        // In this demo we prefer to setup and view the GLWindow directly
-        // this allows the demo to run on -Djava.awt.headless=true systems
-        glWindow.setTitle("Raw GL2ES2 Demo");
-
-        // Finally we connect the GLEventListener application code to the NEWT GLWindow.
-        // GLWindow will call the GLEventListener init, reshape, display and dispose
-        // functions when needed.
-        glWindow.addGLEventListener(this /* GLEventListener */);
-        Animator animator = new Animator();
-        animator.add(glWindow);
-        animator.start();
-    }
-
-    public void init(GLAutoDrawable drawable) {
-        GL2ES2 gl = drawable.getGL().getGL2ES2();
-
-        System.err.println("Chosen GLCapabilities: " + drawable.getChosenGLCapabilities());
-        System.err.println("INIT GL IS: " + gl.getClass().getName());
-        System.err.println("GL_VENDOR: " + gl.glGetString(GL.GL_VENDOR));
-        System.err.println("GL_RENDERER: " + gl.glGetString(GL.GL_RENDERER));
-        System.err.println("GL_VERSION: " + gl.glGetString(GL.GL_VERSION));
-
-        /* The initialization below will use the OpenGL ES 2 API directly
-         * to setup the two shader programs that will be run on the GPU.
-         *
-         * Its recommended to use the jogamp/opengl/util/glsl/ classes
-         * import com.jogamp.opengl.util.glsl.ShaderCode;
-         * import com.jogamp.opengl.util.glsl.ShaderProgram;
-         * import com.jogamp.opengl.util.glsl.ShaderState;
-         * to simplify shader customization, compile and loading.
-         *
-         * You may also want to look at the JOGL RedSquareES2 demo
-         * http://jogamp.org/git/?p=jogl.git;a=blob;f=src/test/com/jogamp/opengl/test/junit/jogl/demos/es2/RedSquareES2.java;hb=HEAD#l78
-         * to see how the shader customization, compile and loading is done
-         * using the recommended JogAmp GLSL utility classes.
-         */
-
-        // Make the shader strings compatible with OpenGL 3 core if needed
-        // GL2ES2 also includes the intersection of GL3 core
-        // The default implicit GLSL version 1.1 is now depricated in GL3 core
-        // GLSL 1.3 is the minimum version that now has to be explicitly set.
-        // This allows the shaders to compile using the latest
-        // desktop OpenGL 3 and 4 drivers.
-        if(gl.isGL3core()){
-            System.out.println("GL3 core detected: explicit add #version 130 to shaders");
-            vertexShaderString = "#version 130\n"+vertexShaderString;
-            fragmentShaderString = "#version 130\n"+fragmentShaderString;
-        }
-
-        // Create GPU shader handles
-        // OpenGL ES retuns a index id to be stored for future reference.
-        vertShader = gl.glCreateShader(GL2ES2.GL_VERTEX_SHADER);
-        fragShader = gl.glCreateShader(GL2ES2.GL_FRAGMENT_SHADER);
-        
-        //Generate textures
-        gl.glGenTextures(1, textureHandle, 0);
-        
-        try {
-			Texture t = loadTexture("test.png");
-			textureHandle[0] = t.getTarget();
-			texture[0] = t;
-			gl.glBindTexture(GL2ES2.GL_TEXTURE_2D, textureHandle[0]);
-		} catch (GLException | IOException e) {
-			// TODO Auto-generated catch block
-			e.printStackTrace();
-		}
-        
-        //Compile the vertexShader String into a program.
-        String[] vlines = new String[] { vertexShaderString };
-        int[] vlengths = new int[] { vlines[0].length() };
-        gl.glShaderSource(vertShader, vlines.length, vlines, vlengths, 0);
-        gl.glCompileShader(vertShader);
-
-        //Check compile status.
-        int[] compiled = new int[1];
-        gl.glGetShaderiv(vertShader, GL2ES2.GL_COMPILE_STATUS, compiled,0);
-        if(compiled[0]!=0){System.out.println("Horray! vertex shader compiled");}
-        else {
-            int[] logLength = new int[1];
-            gl.glGetShaderiv(vertShader, GL2ES2.GL_INFO_LOG_LENGTH, logLength, 0);
-
-            byte[] log = new byte[logLength[0]];
-            gl.glGetShaderInfoLog(vertShader, logLength[0], (int[])null, 0, log, 0);
-
-            System.err.println("Error compiling the vertex shader: " + new String(log));
-            System.exit(1);
-        }
-
-        //Compile the fragmentShader String into a program.
-        String[] flines = new String[] { fragmentShaderString };
-        int[] flengths = new int[] { flines[0].length() };
-        gl.glShaderSource(fragShader, flines.length, flines, flengths, 0);
-        gl.glCompileShader(fragShader);
-
-        //Check compile status.
-        gl.glGetShaderiv(fragShader, GL2ES2.GL_COMPILE_STATUS, compiled,0);
-        if(compiled[0]!=0){System.out.println("Horray! fragment shader compiled");}
-        else {
-            int[] logLength = new int[1];
-            gl.glGetShaderiv(fragShader, GL2ES2.GL_INFO_LOG_LENGTH, logLength, 0);
-
-            byte[] log = new byte[logLength[0]];
-            gl.glGetShaderInfoLog(fragShader, logLength[0], (int[])null, 0, log, 0);
-
-            System.err.println("Error compiling the fragment shader: " + new String(log));
-            System.exit(1);
-        }
-
-        //Each shaderProgram must have
-        //one vertex shader and one fragment shader.
-        shaderProgram = gl.glCreateProgram();
-        gl.glAttachShader(shaderProgram, vertShader);
-        gl.glAttachShader(shaderProgram, fragShader);
-
-        //Associate attribute ids with the attribute names inside
-        //the vertex shader.
-        gl.glBindAttribLocation(shaderProgram, 0, "attribute_Position");
-        gl.glBindAttribLocation(shaderProgram, 1, "attribute_Color");
-        gl.glBindAttribLocation(shaderProgram, 2, "a_TexCoordinate");
-
-        gl.glLinkProgram(shaderProgram);
-
-        //Get a id number to the uniform_Projection matrix
-        //so that we can update it.
-        ModelViewProjectionMatrixHandle = gl.glGetUniformLocation(shaderProgram, "uniform_Projection");
-        mTextureUniformHandle = gl.glGetUniformLocation(shaderProgram, "u_Texture");
-        mTextureCoordinateHandle = gl.glGetAttribLocation(shaderProgram, "a_TexCoordinate");
-        
-        /* GL2ES2 also includes the intersection of GL3 core
-         * GL3 core and later mandates that a "Vector Buffer Object" must
-         * be created and bound before calls such as gl.glDrawArrays is used.
-         * The VBO lines in this demo makes the code forward compatible with
-         * OpenGL 3 and ES 3 core and later where a default
-         * vector buffer object is deprecated.
-         *
-         * Generate two VBO pointers / handles
-         * VBO is data buffers stored inside the graphics card memory.
-         */
-        vboHandles = new int[3];
-        gl.glGenBuffers(3, vboHandles, 0);
-        
-        
-    }
-
-    public void reshape(GLAutoDrawable drawable, int x, int y, int z, int h) {
-        System.out.println("Window resized to width=" + z + " height=" + h);
-        width = z;
-        height = h;
-
-        // Get gl
-        GL2ES2 gl = drawable.getGL().getGL2ES2();
-
-        // Optional: Set viewport
-        // Render to a square at the center of the window.
-        gl.glViewport((width-height)/2,0,height,height);
-    }
-
-    public void display(GLAutoDrawable drawable) {
-        // Update variables used in animation
-        double t1 = System.currentTimeMillis();
-        theta += (t1-t0)*0.005f;
-        t0 = t1;
-        s = Math.sin(theta);
-
-        // Get gl
-        GL2ES2 gl = drawable.getGL().getGL2ES2();
-
-        // Clear screen
-        gl.glClearColor(0, 0, 0, 0f);  // Purple
-        gl.glClear(GL2ES2.GL_STENCIL_BUFFER_BIT |
-                   GL2ES2.GL_COLOR_BUFFER_BIT   |
-                   GL2ES2.GL_DEPTH_BUFFER_BIT   );
-
-        // Use the shaderProgram that got linked during the init part.
-        gl.glUseProgram(shaderProgram);
-
-        /* Change a projection matrix
-         * The matrix multiplications and OpenGL ES2 code below
-         * basically match this OpenGL ES1 code.
-         * note that the model_view_projection matrix gets sent to the vertexShader.
-         *
-         * gl.glLoadIdentity();
-         * gl.glTranslatef(0.0f,0.0f,-0.1f);
-         * gl.glRotatef((float)30f*(float)s,1.0f,0.0f,1.0f);
-         *
-         */
-
-        // Set the active texture unit to texture unit 0.
-        gl.glActiveTexture(textureHandle[0]);
-        
-        // Bind the texture to this unit.
-        gl.glBindTexture(GL2ES2.GL_TEXTURE_2D, mTextureDataHandle);
-        
-        // Tell the texture uniform sampler to use this texture in the shader by binding to texture unit 0.
-        gl.glUniform1i(mTextureUniformHandle, 0);
-        
-        float[] model_view_projection;
-        float[] identity_matrix = {
-            1.0f, 0.0f, 0.0f, 0.0f,
-            0.0f, 1.0f, 0.0f, 0.0f,
-            0.0f, 0.0f, 1.0f, 0.0f,
-            0.0f, 0.0f, 0.0f, 1.0f,
-        };
-        model_view_projection =  identity_matrix;
-//      model_view_projection =  rotate(model_view_projection,30f*(float)s,1.0f,0.0f,1.0f);
-//      model_view_projection =  translate(model_view_projection,-0.5f,-0.5f, 0f);
-
-        // Send the final projection matrix to the vertex shader by
-        // using the uniform location id obtained during the init part.
-        gl.glUniformMatrix4fv(ModelViewProjectionMatrixHandle, 1, false, model_view_projection, 0);
-
-        /*
-         *  Render a triangle:
-         *  The OpenGL ES2 code below basically match this OpenGL code.
-         *
-         *    gl.glBegin(GL_TRIANGLES);                      // Drawing Using Triangles
-         *    gl.glVertex3f( 0.0f, 1.0f, 0.0f);              // Top
-         *    gl.glVertex3f(-1.0f,-1.0f, 0.0f);              // Bottom Left
-         *    gl.glVertex3f( 1.0f,-1.0f, 0.0f);              // Bottom Right
-         *    gl.glEnd();                            // Finished Drawing The Triangle
-         */
-     
-        fbVertices.clear();
-        fbColors.clear();
-        fbTextureCoordinates.clear();
-        
-        fbVertices.put(new float[]{
-        		0.0f,  0.0f, 0.0f, //Top
-                1.0f, 1.0f, 0.0f, //Bottom Left
-                0.0f, 1.0f, 0.0f,  //Bottom Right
-        	});
-        fbColors.put(new float[]{
-        		1.0f, 0.0f, 0.0f, 1.0f, //Top color (red)
-                0.0f, 0.0f, 0.0f, 1.0f, //Bottom Left color (black)
-                1.0f, 1.0f, 0.0f, 1.0f,  //Bottom Right color (yellow)
-            });
-        fbTextureCoordinates.put(new float[]{
-                0.0f, 0.0f,
-                0.0f, 1.0f,
-                1.0f, 0.0f,
-        });
-        fbVertices.put(new float[]{
-        		0.0f,  0.0f, 0.0f,
-                1.0f, 0.0f, 0.0f,
-                1.0f, 1.0f, 0.0f});
-        fbColors.put(new float[]{
-        		1.0f, 0.0f, 0.0f, 1.0f,
-                0.0f, 0.0f, 0.0f, 1.0f,
-                1.0f, 1.0f, 1.0f, 1.0f});
-        fbTextureCoordinates.put(new float[]{
-                0.0f, 1.0f,
-                1.0f, 1.0f,
-                1.0f, 0.0f,
-        });
-        fbColors.position(0);
-        fbVertices.position(0);
-        fbTextureCoordinates.position(0);
-        int numTriangles = fbVertices.limit()/9;
-        
-        // Select the VBO, GPU memory data, to use for vertices
-        gl.glBindBuffer(GL2ES2.GL_ARRAY_BUFFER, vboHandles[VERTICES_IDX]);
-
-        // transfer data to VBO, this perform the copy of data from CPU -> GPU memory
-        int numBytes = numTriangles * 9 * 4;
-        gl.glBufferData(GL.GL_ARRAY_BUFFER, numBytes, fbVertices, GL.GL_STATIC_DRAW);
-
-        // Associate Vertex attribute 0 with the last bound VBO
-        gl.glVertexAttribPointer(0 /* the vertex attribute */, 3,
-                GL2ES2.GL_FLOAT, false /* normalized? */, 0 /* stride */,
-                0 /* The bound VBO data offset */);
-
-        // VBO
-        // gl.glBindBuffer(GL2ES2.GL_ARRAY_BUFFER, 0); // You can unbind the VBO after it have been associated using glVertexAttribPointer
-
-        gl.glEnableVertexAttribArray(0);
-        
-        // Select the VBO, GPU memory data, to use for colors
-        gl.glBindBuffer(GL2ES2.GL_ARRAY_BUFFER, vboHandles[COLOR_IDX]);
-
-        numBytes = numTriangles * 12 * 4;
-        gl.glBufferData(GL.GL_ARRAY_BUFFER, numBytes, fbColors, GL.GL_STATIC_DRAW);
-
-        // Associate Vertex attribute 1 with the last bound VBO
-        gl.glVertexAttribPointer(1 /* the color attribute */, 4 /* four possitions used for each vertex */,
-                                 GL2ES2.GL_FLOAT, false /* normalized? */, 0 /* stride */,
-                                 0 /* The bound VBO data offset */);
-
-        gl.glEnableVertexAttribArray(1);
-        
-        // Select the VBO, GPU memory data, to use for texture
-        gl.glBindBuffer(GL2ES2.GL_ARRAY_BUFFER, vboHandles[TEXTURE_IDX]);
-
-        numBytes = numTriangles * 6 * 4;
-        gl.glBufferData(GL.GL_ARRAY_BUFFER, numBytes, fbTextureCoordinates, GL.GL_STATIC_DRAW);
-
-        // Associate Vertex attribute 1 with the last bound VBO
-        gl.glVertexAttribPointer(mTextureCoordinateHandle /* the texture attribute */, 2 /* two possitions used for each coordinate */,
-                                 GL2ES2.GL_FLOAT, false /* normalized? */, 0 /* stride */,
-                                 0 /* The bound VBO data offset */);
-
-        gl.glEnableVertexAttribArray(mTextureCoordinateHandle);
-
-        
-        gl.glDrawArrays(GL2ES2.GL_TRIANGLES, 0, numTriangles*3); //Draw the vertices as triangle
-
-        gl.glDisableVertexAttribArray(0); // Allow release of vertex position memory
-        gl.glDisableVertexAttribArray(1); // Allow release of vertex color memory
-        gl.glDisableVertexAttribArray(mTextureCoordinateHandle); // Allow release of vertex texture memory
-        
-//        disp.di
-    }
-    
-    public void drawQuad() {
-    	
-    }
-
-    public void dispose(GLAutoDrawable drawable){
-        System.out.println("cleanup, remember to release shaders");
-        GL2ES2 gl = drawable.getGL().getGL2ES2();
-        gl.glUseProgram(0);
-        gl.glDeleteBuffers(3, vboHandles, 0); // Release VBO, color and vertices, buffer GPU memory.
-        vboHandles = null;
-        gl.glDetachShader(shaderProgram, vertShader);
-        gl.glDeleteShader(vertShader);
-        gl.glDetachShader(shaderProgram, fragShader);
-        gl.glDeleteShader(fragShader);
-        gl.glDeleteProgram(shaderProgram);
-        System.exit(0);
-    }
-    
-    public static Texture loadTexture(String file) throws GLException, IOException
-    {
-        ByteArrayOutputStream os = new ByteArrayOutputStream();
-        ImageIO.write(ImageIO.read(new File(file)), "png", os);
-        InputStream fis = new ByteArrayInputStream(os.toByteArray());
-        return TextureIO.newTexture(fis, true, TextureIO.PNG);
-    }
-    
-}

src/org/warp/picalculator/gui/graphicengine/gpu/DeallocationHelper.java

@@ -0,0 +1,706 @@
+/**
+ * Copyright (c) 2006-2016 Julien Gouesse This program is free software; you can
+ * redistribute it and/or modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version. This program is distributed
+ * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received
+ * a copy of the GNU General Public License along with this program; if not,
+ * write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+package org.warp.picalculator.gui.graphicengine.gpu;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.nio.Buffer;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.CharBuffer;
+import java.nio.DoubleBuffer;
+import java.nio.FloatBuffer;
+import java.nio.IntBuffer;
+import java.nio.LongBuffer;
+import java.nio.ShortBuffer;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+/**
+ * Helper to deallocate memory on the native heap allocated during the creation
+ * of a direct byte buffer. It supports numerous virtual machines including
+ * OpenJDK, Oracle/Sun Java, Android Dalvik Virtual Machine, Apache Harmony and
+ * GNU Classpath. This class uses the syntax of Java 1.7 but it can work
+ * correctly with Java 1.4 with a very few minor type changes when using the
+ * maps and the collections. It relies on lots of implementation details but
+ * it's robust enough to go on working (except when the implementors
+ * intentionally use a very general class to store the buffers) despite minor
+ * naming changes like those that occurred between Java 1.6 and Java 1.7. It
+ * supports Java 1.9 despite the move of the cleaner from the package sun.misc
+ * to jdk.internal.ref (in the module java.base). N.B: Releasing the native
+ * memory of a sliced direct NIO buffer, the one of a direct NIO buffer created
+ * with JNI or the one of any direct NIO buffer created by the virtual machine
+ * or by a framework not under your control doesn't prevent the calls to methods
+ * attempting to access such buffers. Those calls can throw an exception or
+ * crash the virtual machine depending on the implementations.
+ * 
+ * @author Julien Gouesse
+ */
+public class DeallocationHelper {
+
+	/**
+	 * tool responsible for releasing the native memory of a deallocatable byte
+	 * buffer
+	 */
+	public static abstract class Deallocator {
+
+		public Deallocator() {
+			super();
+		}
+
+		/**
+		 * releases the native memory of a deallocatable byte buffer
+		 * 
+		 * @param directByteBuffer
+		 *            deallocatable byte buffer
+		 * 
+		 * @return <code>true</code> if the deallocation is successful,
+		 *         otherwise <code>false</code>
+		 */
+		public abstract boolean run(final ByteBuffer directByteBuffer);
+	}
+
+	public static class OracleSunOpenJdkDeallocator extends Deallocator {
+
+		private Method directByteBufferCleanerMethod;
+
+		private Method cleanerCleanMethod;
+
+		public OracleSunOpenJdkDeallocator() {
+			super();
+			try {
+				final Class<?> directByteBufferClass = Class.forName("java.nio.DirectByteBuffer");
+				directByteBufferCleanerMethod = directByteBufferClass.getDeclaredMethod("cleaner");
+				/**
+				 * The return type is sun.misc.Cleaner in Java <= 1.8,
+				 * jdk.internal.ref.Cleaner in Java >= 1.9. Only the latter
+				 * implements the Runnable interface.
+				 */
+				final Class<?> cleanerClass = directByteBufferCleanerMethod.getReturnType();
+				if (Runnable.class.isAssignableFrom(cleanerClass)) {
+					cleanerCleanMethod = Runnable.class.getDeclaredMethod("run");
+				} else {
+					cleanerCleanMethod = cleanerClass.getDeclaredMethod("clean");
+				}
+			} catch (ClassNotFoundException | NoSuchMethodException e) {
+				logger.log(Level.WARNING, "The initialization of the deallocator for Oracle Java, Sun Java and OpenJDK has failed", e);
+			}
+		}
+
+		@Override
+		public boolean run(final ByteBuffer directByteBuffer) {
+			boolean success = false;
+			if (directByteBufferCleanerMethod != null && cleanerCleanMethod != null) {
+				final boolean directByteBufferCleanerMethodWasAccessible = directByteBufferCleanerMethod.isAccessible();
+				final boolean cleanerCleanMethodWasAccessible = cleanerCleanMethod.isAccessible();
+				try {
+					// according to the Java documentation, by default, a reflected object is not accessible
+					directByteBufferCleanerMethod.setAccessible(true);
+					final Object cleaner = directByteBufferCleanerMethod.invoke(directByteBuffer);
+					if (cleaner != null) {
+						cleanerCleanMethod.setAccessible(true);
+						cleanerCleanMethod.invoke(cleaner);
+						success = true;
+					}
+				} catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+					logger.log(Level.WARNING, "The deallocation of a direct NIO buffer has failed", e);
+				} finally {
+					directByteBufferCleanerMethod.setAccessible(directByteBufferCleanerMethodWasAccessible);
+					cleanerCleanMethod.setAccessible(cleanerCleanMethodWasAccessible);
+				}
+			}
+			return (success);
+		}
+	}
+
+	public static class AndroidDeallocator extends Deallocator {
+
+		private Method directByteBufferFreeMethod;
+
+		public AndroidDeallocator() {
+			super();
+			try {
+				final Class<?> directByteBufferClass = Class.forName("java.nio.DirectByteBuffer");
+				directByteBufferFreeMethod = directByteBufferClass.getDeclaredMethod("free");
+			} catch (ClassNotFoundException | NoSuchMethodException e) {
+				logger.log(Level.WARNING, "The initialization of the deallocator for Android has failed", e);
+			}
+		}
+
+		@Override
+		public boolean run(final ByteBuffer directByteBuffer) {
+			boolean success = false;
+			if (directByteBufferFreeMethod != null) {
+				final boolean directByteBufferFreeMethodWasAccessible = directByteBufferFreeMethod.isAccessible();
+				try {
+					directByteBufferFreeMethod.setAccessible(true);
+					directByteBufferFreeMethod.invoke(directByteBuffer);
+					success = true;
+				} catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+					logger.log(Level.WARNING, "The deallocation of a direct NIO buffer has failed", e);
+				} finally {
+					directByteBufferFreeMethod.setAccessible(directByteBufferFreeMethodWasAccessible);
+				}
+			}
+			return (success);
+		}
+	}
+
+	public static class GnuClasspathDeallocator extends Deallocator {
+
+		private Method vmDirectByteBufferFreeMethod;
+
+		private Field bufferAddressField;
+
+		public GnuClasspathDeallocator() {
+			super();
+			try {
+				final Class<?> vmDirectByteBufferClass = Class.forName("java.nio.VMDirectByteBuffer");
+				final Class<?> gnuClasspathPointerClass = Class.forName("gnu.classpath.Pointer");
+				vmDirectByteBufferFreeMethod = vmDirectByteBufferClass.getDeclaredMethod("free", gnuClasspathPointerClass);
+				bufferAddressField = Buffer.class.getDeclaredField("address");
+			} catch (ClassNotFoundException | NoSuchMethodException | NoSuchFieldException e) {
+				logger.log(Level.WARNING, "The initialization of the deallocator for GNU Classpath has failed", e);
+			}
+		}
+
+		@Override
+		public boolean run(final ByteBuffer directByteBuffer) {
+			boolean success = false;
+			if (vmDirectByteBufferFreeMethod != null && bufferAddressField != null) {
+				final boolean bufferAddressFieldWasAccessible = bufferAddressField.isAccessible();
+				final boolean vmDirectByteBufferFreeMethodWasAccessible = vmDirectByteBufferFreeMethod.isAccessible();
+				try {
+					bufferAddressField.setAccessible(true);
+					final Object address = bufferAddressField.get(directByteBuffer);
+					if (address != null) {
+						vmDirectByteBufferFreeMethod.setAccessible(true);
+						vmDirectByteBufferFreeMethod.invoke(null, address);
+						success = true;
+					}
+				} catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+					logger.log(Level.WARNING, "The deallocation of a direct NIO buffer has failed", e);
+				} finally {
+					bufferAddressField.setAccessible(bufferAddressFieldWasAccessible);
+					vmDirectByteBufferFreeMethod.setAccessible(vmDirectByteBufferFreeMethodWasAccessible);
+				}
+			}
+			return (success);
+		}
+	}
+
+	public static class ApacheHarmonyDeallocator extends Deallocator {
+
+		private Method directByteBufferFreeMethod;
+
+		public ApacheHarmonyDeallocator() {
+			super();
+			try {
+				final Class<?> directByteBufferClass = Class.forName("java.nio.DirectByteBuffer");
+				directByteBufferFreeMethod = directByteBufferClass.getDeclaredMethod("free");
+			} catch (ClassNotFoundException | NoSuchMethodException e) {
+				logger.log(Level.WARNING, "The initialization of the deallocator for Apache Harmony has failed", e);
+			}
+		}
+
+		@Override
+		public boolean run(final ByteBuffer directByteBuffer) {
+			boolean success = false;
+			if (directByteBufferFreeMethod != null) {
+				final boolean directByteBufferFreeMethodWasAccessible = directByteBufferFreeMethod.isAccessible();
+				try {
+					directByteBufferFreeMethod.setAccessible(true);
+					directByteBufferFreeMethod.invoke(directByteBuffer);
+					success = true;
+				} catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+					logger.log(Level.WARNING, "The deallocation of a direct NIO buffer has failed", e);
+				} finally {
+					directByteBufferFreeMethod.setAccessible(directByteBufferFreeMethodWasAccessible);
+				}
+			}
+			return (success);
+		}
+	}
+
+	private static final Logger logger = Logger.getLogger(DeallocationHelper.class.getName());
+
+	private Map<Class<?>, Field> attachmentOrByteBufferFieldMap;
+
+	private Set<Class<?>> deallocatableBufferClassSet;
+
+	private Deallocator deallocator;
+
+	/**
+	 * Default constructor
+	 */
+	public DeallocationHelper() {
+		this(false);
+	}
+
+	/**
+	 * Main constructor
+	 * 
+	 * @param ignoreClassesAndFieldsHints
+	 *            <code>true</code> if the known implementation details should
+	 *            be ignored when looking for the classes and the fields used
+	 *            for the native memory of the direct buffers (they are then
+	 *            fully recomputed at runtime which is slower but safer),
+	 *            otherwise <code>false</code>
+	 */
+	public DeallocationHelper(final boolean ignoreClassesAndFieldsHints) {
+		super();
+		final List<Buffer> buffersToDelete = new ArrayList<>();
+		/**
+		 * builds the map used to determine the names of the fields containing
+		 * the direct byte buffers. The direct read only buffers and the sliced
+		 * buffers and the direct buffers for other primitive types than bytes
+		 * store their data into some direct byte buffers. Those direct byte
+		 * buffers often are the only one accessing directly to the native
+		 * memory. That's why it's necessary to find them when a developer
+		 * passes a direct NIO buffer. The code below relies on numerous
+		 * implementation details found in some classes not available in the
+		 * public APIs, it's used to find the fields faster in most of the
+		 * cases. The class names haven't changed since Java 1.4 unlike a few
+		 * field names.
+		 */
+		final Map<String, String> attachmentOrByteBufferFieldNameMap = new HashMap<>();
+		final String javaVendor = System.getProperty("java.vendor");
+		final String javaVersion = System.getProperty("java.version");
+		if (!ignoreClassesAndFieldsHints) {
+			if (javaVendor.equals("Sun Microsystems Inc.") || javaVendor.equals("Oracle Corporation")) {
+				final String java14to16DirectBufferAttachmentFieldName = "viewedBuffer";
+				final String java17to19DirectBufferAttachmentFieldName = "att";
+				final String byteBufferAsNonByteBufferByteBufferFieldName = "bb";
+				final String[] directBufferClassnames = new String[] { "java.nio.DirectByteBuffer", "java.nio.DirectByteBufferR", "java.nio.DirectCharBufferRS", "java.nio.DirectCharBufferRU", "java.nio.DirectCharBufferS", "java.nio.DirectCharBufferU", "java.nio.DirectDoubleBufferRS", "java.nio.DirectDoubleBufferRU", "java.nio.DirectDoubleBufferS", "java.nio.DirectDoubleBufferU", "java.nio.DirectFloatBufferRS", "java.nio.DirectFloatBufferRU", "java.nio.DirectFloatBufferS", "java.nio.DirectFloatBufferU", "java.nio.DirectIntBufferRS", "java.nio.DirectIntBufferRU", "java.nio.DirectIntBufferS", "java.nio.DirectIntBufferU", "java.nio.DirectLongBufferRS", "java.nio.DirectLongBufferRU", "java.nio.DirectLongBufferS", "java.nio.DirectLongBufferU", "java.nio.DirectShortBufferRS", "java.nio.DirectShortBufferRU", "java.nio.DirectShortBufferS", "java.nio.DirectShortBufferU" };
+				final String[] byteBufferAsNonByteBufferClassnames = new String[] { "java.nio.ByteBufferAsCharBufferB", "java.nio.ByteBufferAsCharBufferL", "java.nio.ByteBufferAsCharBufferRB", "java.nio.ByteBufferAsCharBufferRL", "java.nio.ByteBufferAsDoubleBufferB", "java.nio.ByteBufferAsDoubleBufferL", "java.nio.ByteBufferAsDoubleBufferRB", "java.nio.ByteBufferAsDoubleBufferRL", "java.nio.ByteBufferAsFloatBufferB", "java.nio.ByteBufferAsFloatBufferL", "java.nio.ByteBufferAsFloatBufferRB", "java.nio.ByteBufferAsFloatBufferRL", "java.nio.ByteBufferAsIntBufferB", "java.nio.ByteBufferAsIntBufferL", "java.nio.ByteBufferAsIntBufferRB", "java.nio.ByteBufferAsIntBufferRL", "java.nio.ByteBufferAsLongBufferB", "java.nio.ByteBufferAsLongBufferL", "java.nio.ByteBufferAsLongBufferRB", "java.nio.ByteBufferAsLongBufferRL", "java.nio.ByteBufferAsShortBufferB", "java.nio.ByteBufferAsShortBufferL", "java.nio.ByteBufferAsShortBufferRB", "java.nio.ByteBufferAsShortBufferRL" };
+				final String[] javaVersionElements = System.getProperty("java.version").split("\\.");
+				final int indexOfEarlyAccessSuffix = javaVersionElements[0].lastIndexOf("-ea");
+				if (indexOfEarlyAccessSuffix != -1) {
+					// drops the "-ea" suffix from the major version number for
+					// an early access build
+					javaVersionElements[0] = javaVersionElements[0].substring(0, indexOfEarlyAccessSuffix);
+				}
+				final int major, minor;
+				if (javaVersionElements.length >= 2) {
+					major = Integer.parseInt(javaVersionElements[0]);
+					minor = Integer.parseInt(javaVersionElements[1]);
+				} else {
+					major = 1;
+					minor = Integer.parseInt(javaVersionElements[0]);
+				}
+				final String directBufferAttachmentFieldName;
+				if (minor == 1 && major <= 6) {
+					directBufferAttachmentFieldName = java14to16DirectBufferAttachmentFieldName;
+				} else {
+					directBufferAttachmentFieldName = java17to19DirectBufferAttachmentFieldName;
+				}
+				for (final String directBufferClassname : directBufferClassnames) {
+					attachmentOrByteBufferFieldNameMap.put(directBufferClassname, directBufferAttachmentFieldName);
+				}
+				for (final String byteBufferAsNonByteBufferClassname : byteBufferAsNonByteBufferClassnames) {
+					attachmentOrByteBufferFieldNameMap.put(byteBufferAsNonByteBufferClassname, byteBufferAsNonByteBufferByteBufferFieldName);
+				}
+			} else if (javaVendor.equals("The Android Project")) {
+				final String byteBufferAsNonByteBufferByteBufferFieldName = "byteBuffer";
+				final String[] byteBufferAsNonByteBufferClassnames = new String[] { "java.nio.ByteBufferAsCharBuffer", "java.nio.ByteBufferAsDoubleBuffer", "java.nio.ByteBufferAsFloatBuffer", "java.nio.ByteBufferAsIntBuffer", "java.nio.ByteBufferAsLongBuffer", "java.nio.ByteBufferAsShortBuffer" };
+				for (final String byteBufferAsNonByteBufferClassname : byteBufferAsNonByteBufferClassnames) {
+					attachmentOrByteBufferFieldNameMap.put(byteBufferAsNonByteBufferClassname, byteBufferAsNonByteBufferByteBufferFieldName);
+				}
+			} else if (/* javaVendor.equals("Apple Inc.")|| */javaVendor.equals("Free Software Foundation, Inc.")) {
+				final String byteBufferAsNonByteBufferByteBufferFieldName = "bb";
+				final String[] byteBufferAsNonByteBufferClassnames = new String[] { "java.nio.CharViewBufferImpl", "java.nio.DoubleViewBufferImpl", "java.nio.FloatViewBufferImpl", "java.nio.IntViewBufferImpl", "java.nio.LongViewBufferImpl", "java.nio.ShortViewBufferImpl" };
+				for (final String byteBufferAsNonByteBufferClassname : byteBufferAsNonByteBufferClassnames) {
+					attachmentOrByteBufferFieldNameMap.put(byteBufferAsNonByteBufferClassname, byteBufferAsNonByteBufferByteBufferFieldName);
+				}
+			} else if (javaVendor.contains("Apache")) {
+				final String byteBufferAsNonByteBufferByteBufferFieldName = "byteBuffer";
+				final String[] byteBufferAsNonByteBufferClassnames = new String[] { "java.nio.CharToByteBufferAdapter", "java.nio.DoubleToByteBufferAdapter", "java.nio.FloatToByteBufferAdapter", "java.nio.IntToByteBufferAdapter", "java.nio.LongToByteBufferAdapter", "java.nio.ShortToByteBufferAdapter" };
+				for (final String byteBufferAsNonByteBufferClassname : byteBufferAsNonByteBufferClassnames) {
+					attachmentOrByteBufferFieldNameMap.put(byteBufferAsNonByteBufferClassname, byteBufferAsNonByteBufferByteBufferFieldName);
+				}
+			} else if (javaVendor.equals("Jeroen Frijters")) {// TODO IKVM
+			} else if (javaVendor.contains("IBM")) {// TODO J9
+			}
+		}
+		// checks if these classes are in the class library
+		if (!attachmentOrByteBufferFieldNameMap.isEmpty()) {
+			final List<String> classnamesToRemove = new ArrayList<>();
+			for (final String classname : attachmentOrByteBufferFieldNameMap.keySet()) {
+				try {
+					Class.forName(classname);
+				} catch (final ClassNotFoundException cnfe) {
+					classnamesToRemove.add(classname);
+				}
+			}
+			for (final String classnameToRemove : classnamesToRemove) {
+				attachmentOrByteBufferFieldNameMap.remove(classnameToRemove);
+			}
+		}
+		// builds the map used to determine the fields containing the direct
+		// byte buffers
+		attachmentOrByteBufferFieldMap = new HashMap<>();
+		if (!attachmentOrByteBufferFieldNameMap.isEmpty()) {
+			for (final Entry<String, String> attachmentOrByteBufferFieldNameEntry : attachmentOrByteBufferFieldNameMap.entrySet()) {
+				final String classname = attachmentOrByteBufferFieldNameEntry.getKey();
+				final String fieldname = attachmentOrByteBufferFieldNameEntry.getValue();
+				try {
+					final Class<?> bufferClass = Class.forName(classname);
+					Field bufferField = null;
+					Class<?> bufferIntermediaryClass = bufferClass;
+					final List<Class<?>> intermediaryClassWithoutBufferList = new ArrayList<>();
+					while (bufferIntermediaryClass != null) {
+						try {
+							bufferField = bufferIntermediaryClass.getDeclaredField(fieldname);
+						} catch (final NoSuchFieldException nsfe) {
+							if (!bufferIntermediaryClass.equals(Object.class) && !bufferIntermediaryClass.equals(Buffer.class)) {
+								intermediaryClassWithoutBufferList.add(bufferIntermediaryClass);
+							}
+						}
+						bufferIntermediaryClass = bufferIntermediaryClass.getSuperclass();
+					}
+					if (bufferField == null) {
+						final String superClassesMsg;
+						if (intermediaryClassWithoutBufferList.isEmpty()) {
+							superClassesMsg = "";
+						} else if (intermediaryClassWithoutBufferList.size() == 1) {
+							superClassesMsg = " and in its super class " + intermediaryClassWithoutBufferList.get(0).getName();
+						} else {
+							final StringBuilder builder = new StringBuilder();
+							builder.append(" and in its super classes");
+							int classIndex = 0;
+							for (final Class<?> intermediaryClassWithoutBuffer : intermediaryClassWithoutBufferList) {
+								builder.append(' ');
+								builder.append(intermediaryClassWithoutBuffer.getName());
+								if (classIndex < intermediaryClassWithoutBufferList.size() - 1) {
+									builder.append(',');
+								}
+								classIndex++;
+							}
+							superClassesMsg = builder.toString();
+						}
+						logger.warning("The field " + fieldname + " hasn't been found in the class " + classname + superClassesMsg);
+					} else {// the field has been found, stores it into the map
+						attachmentOrByteBufferFieldMap.put(bufferClass, bufferField);
+					}
+				} catch (final ClassNotFoundException cnfe) {// TODO The Java version
+															// isn't very useful
+														// under
+														// Android as it is
+														// always zero, rather
+														// use
+														// android.os.Build.VERSION.RELEASE
+														// to show something
+														// meaningful supported
+														// since the API level 1
+					final String msg = "The class " + classname + " hasn't been found while initializing the deallocator. Java vendor: " + javaVendor + " Java version: " + javaVersion;
+					logger.log(Level.WARNING, msg, cnfe);
+				}
+			}
+		}
+		// if a known implementation has drastically changed or if the current
+		// implementation is unknown
+		if (attachmentOrByteBufferFieldNameMap.isEmpty()) {// detects everything
+																// with the
+															// reflection API
+															// creates all
+															// possible kinds of
+															// direct NIO buffer
+															// that can contain
+															// buffers (sliced
+															// buffers and views)
+			final ByteBuffer slicedBigEndianReadOnlyDirectByteBuffer = ((ByteBuffer) ByteBuffer.allocateDirect(2).order(ByteOrder.BIG_ENDIAN).put((byte) 0).put((byte) 0).position(1).limit(2)).slice().asReadOnlyBuffer();
+			final ByteBuffer slicedBigEndianReadWriteDirectByteBuffer = ((ByteBuffer) ByteBuffer.allocateDirect(2).order(ByteOrder.BIG_ENDIAN).put((byte) 0).put((byte) 0).position(1).limit(2)).slice();
+			final CharBuffer bigEndianReadOnlyDirectCharBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asReadOnlyBuffer().asCharBuffer();
+			final CharBuffer bigEndianReadWriteDirectCharBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asCharBuffer();
+			final DoubleBuffer bigEndianReadOnlyDirectDoubleBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asReadOnlyBuffer().asDoubleBuffer();
+			final DoubleBuffer bigEndianReadWriteDirectDoubleBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asDoubleBuffer();
+			final FloatBuffer bigEndianReadOnlyDirectFloatBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asReadOnlyBuffer().asFloatBuffer();
+			final FloatBuffer bigEndianReadWriteDirectFloatBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asFloatBuffer();
+			final IntBuffer bigEndianReadOnlyDirectIntBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asReadOnlyBuffer().asIntBuffer();
+			final IntBuffer bigEndianReadWriteDirectIntBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asIntBuffer();
+			final LongBuffer bigEndianReadOnlyDirectLongBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asReadOnlyBuffer().asLongBuffer();
+			final LongBuffer bigEndianReadWriteDirectLongBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asLongBuffer();
+			final ShortBuffer bigEndianReadOnlyDirectShortBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asReadOnlyBuffer().asShortBuffer();
+			final ShortBuffer bigEndianReadWriteDirectShortBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.BIG_ENDIAN).asShortBuffer();
+			final ByteBuffer slicedLittleEndianReadOnlyDirectByteBuffer = ((ByteBuffer) ByteBuffer.allocateDirect(2).order(ByteOrder.LITTLE_ENDIAN).put((byte) 0).put((byte) 0).position(1).limit(2)).slice().asReadOnlyBuffer();
+			final ByteBuffer slicedLittleEndianReadWriteDirectByteBuffer = ((ByteBuffer) ByteBuffer.allocateDirect(2).order(ByteOrder.LITTLE_ENDIAN).put((byte) 0).put((byte) 0).position(1).limit(2)).slice();
+			final CharBuffer littleEndianReadOnlyDirectCharBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asReadOnlyBuffer().asCharBuffer();
+			final CharBuffer littleEndianReadWriteDirectCharBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asCharBuffer();
+			final DoubleBuffer littleEndianReadOnlyDirectDoubleBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asReadOnlyBuffer().asDoubleBuffer();
+			final DoubleBuffer littleEndianReadWriteDirectDoubleBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asDoubleBuffer();
+			final FloatBuffer littleEndianReadOnlyDirectFloatBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asReadOnlyBuffer().asFloatBuffer();
+			final FloatBuffer littleEndianReadWriteDirectFloatBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asFloatBuffer();
+			final IntBuffer littleEndianReadOnlyDirectIntBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asReadOnlyBuffer().asIntBuffer();
+			final IntBuffer littleEndianReadWriteDirectIntBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asIntBuffer();
+			final LongBuffer littleEndianReadOnlyDirectLongBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asReadOnlyBuffer().asLongBuffer();
+			final LongBuffer littleEndianReadWriteDirectLongBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asLongBuffer();
+			final ShortBuffer littleEndianReadOnlyDirectShortBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asReadOnlyBuffer().asShortBuffer();
+			final ShortBuffer littleEndianReadWriteDirectShortBuffer = ByteBuffer.allocateDirect(1).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer();
+			final List<Buffer> buffers = new ArrayList<>();
+			buffers.add(slicedBigEndianReadOnlyDirectByteBuffer);
+			buffers.add(slicedBigEndianReadWriteDirectByteBuffer);
+			buffers.add(bigEndianReadOnlyDirectCharBuffer);
+			buffers.add(bigEndianReadWriteDirectCharBuffer);
+			buffers.add(bigEndianReadOnlyDirectDoubleBuffer);
+			buffers.add(bigEndianReadWriteDirectDoubleBuffer);
+			buffers.add(bigEndianReadOnlyDirectFloatBuffer);
+			buffers.add(bigEndianReadWriteDirectFloatBuffer);
+			buffers.add(bigEndianReadOnlyDirectIntBuffer);
+			buffers.add(bigEndianReadWriteDirectIntBuffer);
+			buffers.add(bigEndianReadOnlyDirectLongBuffer);
+			buffers.add(bigEndianReadWriteDirectLongBuffer);
+			buffers.add(bigEndianReadOnlyDirectShortBuffer);
+			buffers.add(bigEndianReadWriteDirectShortBuffer);
+			buffers.add(slicedLittleEndianReadOnlyDirectByteBuffer);
+			buffers.add(slicedLittleEndianReadWriteDirectByteBuffer);
+			buffers.add(littleEndianReadOnlyDirectCharBuffer);
+			buffers.add(littleEndianReadWriteDirectCharBuffer);
+			buffers.add(littleEndianReadOnlyDirectDoubleBuffer);
+			buffers.add(littleEndianReadWriteDirectDoubleBuffer);
+			buffers.add(littleEndianReadOnlyDirectFloatBuffer);
+			buffers.add(littleEndianReadWriteDirectFloatBuffer);
+			buffers.add(littleEndianReadOnlyDirectIntBuffer);
+			buffers.add(littleEndianReadWriteDirectIntBuffer);
+			buffers.add(littleEndianReadOnlyDirectLongBuffer);
+			buffers.add(littleEndianReadWriteDirectLongBuffer);
+			buffers.add(littleEndianReadOnlyDirectShortBuffer);
+			buffers.add(littleEndianReadWriteDirectShortBuffer);
+			// gets the fields to access the contained buffers
+			for (final Buffer buffer : buffers) {
+				final Class<?> bufferClass = buffer.getClass();
+				if (!attachmentOrByteBufferFieldMap.containsKey(bufferClass)) {
+					Field bufferField = null;
+					Class<?> bufferIntermediaryClass = bufferClass;
+					while (bufferIntermediaryClass != null && bufferField == null) {
+						for (final Field field : bufferIntermediaryClass.getDeclaredFields()) {
+							final boolean fieldWasAccessible = field.isAccessible();
+							try {
+								field.setAccessible(true);
+								final Object fieldValue = field.get(buffer);
+								if (fieldValue != null && fieldValue instanceof Buffer) {
+									bufferField = field;
+									break;
+								}
+							} catch (final IllegalAccessException iae) {
+								logger.log(Level.WARNING, "Cannot access the field " + field.getName() + " of the class " + bufferIntermediaryClass.getName(), iae);
+							} finally {
+								field.setAccessible(fieldWasAccessible);
+							}
+						}
+						bufferIntermediaryClass = bufferIntermediaryClass.getSuperclass();
+					}
+					if (bufferField != null) {
+						attachmentOrByteBufferFieldMap.put(bufferClass, bufferField);
+					}
+				}
+			}
+			// cleans the mess
+			buffersToDelete.addAll(buffers);
+		}
+		// builds the set of classes whose instances can be deallocated
+		deallocatableBufferClassSet = new HashSet<>();
+		if (javaVendor.equals("Sun Microsystems Inc.") || javaVendor.equals("Oracle Corporation") || javaVendor.equals("The Android Project")) {
+			Class<?> directByteBufferClass = null;
+			final String directByteBufferClassName = "java.nio.DirectByteBuffer";
+			try {
+				directByteBufferClass = Class.forName(directByteBufferClassName);
+			} catch (final ClassNotFoundException cnfe) {
+				final String msg = "The class " + directByteBufferClassName + " hasn't been found while initializing the deallocator. Java vendor: " + javaVendor + " Java version: " + javaVersion;
+				logger.log(Level.WARNING, msg, cnfe);
+			}
+			if (directByteBufferClass != null) {
+				deallocatableBufferClassSet.add(directByteBufferClass);
+			}
+		} else if (/* javaVendor.equals("Apple Inc.")|| */javaVendor.equals("Free Software Foundation, Inc.")) {
+			Class<?> readOnlyDirectByteBufferClass = null;
+			final String readOnlyDirectByteBufferClassName = "java.nio.DirectByteBufferImpl.ReadOnly";
+			try {
+				readOnlyDirectByteBufferClass = Class.forName(readOnlyDirectByteBufferClassName);
+			} catch (final ClassNotFoundException cnfe) {
+				final String msg = "The class " + readOnlyDirectByteBufferClassName + " hasn't been found while initializing the deallocator. Java vendor: " + javaVendor + " Java version: " + javaVersion;
+				logger.log(Level.WARNING, msg, cnfe);
+			}
+			if (readOnlyDirectByteBufferClass != null) {
+				deallocatableBufferClassSet.add(readOnlyDirectByteBufferClass);
+			}
+			Class<?> readWriteDirectByteBufferClass = null;
+			final String readWriteDirectByteBufferClassName = "java.nio.DirectByteBufferImpl.ReadWrite";
+			try {
+				readWriteDirectByteBufferClass = Class.forName(readWriteDirectByteBufferClassName);
+			} catch (final ClassNotFoundException cnfe) {
+				final String msg = "The class " + readWriteDirectByteBufferClassName + " hasn't been found while initializing the deallocator. Java vendor: " + javaVendor + " Java version: " + javaVersion;
+				logger.log(Level.WARNING, msg, cnfe);
+			}
+			if (readWriteDirectByteBufferClass != null) {
+				deallocatableBufferClassSet.add(readWriteDirectByteBufferClass);
+			}
+		} else if (javaVendor.contains("Apache")) {
+			Class<?> readOnlyDirectByteBufferClass = null;
+			final String readOnlyDirectByteBufferClassName = "java.nio.ReadOnlyDirectByteBuffer";
+			try {
+				readOnlyDirectByteBufferClass = Class.forName(readOnlyDirectByteBufferClassName);
+			} catch (final ClassNotFoundException cnfe) {
+				final String msg = "The class " + readOnlyDirectByteBufferClassName + " hasn't been found while initializing the deallocator. Java vendor: " + javaVendor + " Java version: " + javaVersion;
+				logger.log(Level.WARNING, msg, cnfe);
+			}
+			if (readOnlyDirectByteBufferClass != null) {
+				deallocatableBufferClassSet.add(readOnlyDirectByteBufferClass);
+			}
+			Class<?> readWriteDirectByteBufferClass = null;
+			final String readWriteDirectByteBufferClassName = "java.nio.ReadWriteDirectByteBuffer";
+			try {
+				readWriteDirectByteBufferClass = Class.forName(readWriteDirectByteBufferClassName);
+			} catch (final ClassNotFoundException cnfe) {
+				final String msg = "The class " + readWriteDirectByteBufferClassName + " hasn't been found while initializing the deallocator. Java vendor: " + javaVendor + " Java version: " + javaVersion;
+				logger.log(Level.WARNING, msg, cnfe);
+			}
+			if (readWriteDirectByteBufferClass != null) {
+				deallocatableBufferClassSet.add(readWriteDirectByteBufferClass);
+			}
+		} else if (javaVendor.equals("Jeroen Frijters")) {// TODO IKVM
+		} else if (javaVendor.contains("IBM")) {// TODO J9
+		}
+		// if there is no known implementation class of the direct byte buffers
+		if (deallocatableBufferClassSet.isEmpty()) {// creates a read write
+														// direct byte buffer
+			final ByteBuffer dummyReadWriteDirectByteBuffer = ByteBuffer.allocateDirect(1);
+			// gets its class
+			final Class<?> readWriteDirectByteBufferClass = dummyReadWriteDirectByteBuffer.getClass();
+			// stores this class
+			deallocatableBufferClassSet.add(readWriteDirectByteBufferClass);
+			// cleans the mess
+			buffersToDelete.add(dummyReadWriteDirectByteBuffer);
+			// creates a read only direct byte buffer
+			final ByteBuffer dummyReadOnlyDirectByteBuffer = ByteBuffer.allocateDirect(1).asReadOnlyBuffer();
+			// gets its class
+			final Class<?> readOnlyDirectByteBufferClass = dummyReadOnlyDirectByteBuffer.getClass();
+			// stores this class
+			deallocatableBufferClassSet.add(readOnlyDirectByteBufferClass);
+			// cleans the mess
+			buffersToDelete.add(dummyReadOnlyDirectByteBuffer);
+		}
+		// builds the deallocator responsible for releasing the native memory of
+		// a deallocatable byte buffer
+		if (javaVendor.equals("Sun Microsystems Inc.") || javaVendor.equals("Oracle Corporation")) {
+			deallocator = new OracleSunOpenJdkDeallocator();
+		} else if (javaVendor.equals("The Android Project")) {
+			deallocator = new AndroidDeallocator();
+		} else if (/* javaVendor.equals("Apple Inc.")|| */javaVendor.equals("Free Software Foundation, Inc.")) {
+			deallocator = new GnuClasspathDeallocator();
+		} else if (javaVendor.contains("Apache")) {
+			deallocator = new ApacheHarmonyDeallocator();
+		} else if (javaVendor.equals("Jeroen Frijters")) {// TODO IKVM
+			deallocator = null;
+		} else if (javaVendor.contains("IBM")) {// TODO J9
+			deallocator = null;
+		} else {
+			deallocator = null;
+		}
+		// final cleanup
+		for (final Buffer bufferToDelete : buffersToDelete) {
+			deallocate(bufferToDelete);
+		}
+	}
+
+	public ByteBuffer findDeallocatableBuffer(Buffer buffer) {
+		final ByteBuffer deallocatableDirectByteBuffer;
+		// looks only for the direct buffers
+		if (buffer != null && buffer.isDirect()) {// looks for any contained
+														// buffer in the passed buffer
+			final Class<?> bufferClass = buffer.getClass();
+			final Field attachmentOrByteBufferField = attachmentOrByteBufferFieldMap == null ? null : attachmentOrByteBufferFieldMap.get(bufferClass);
+			final Buffer attachmentBufferOrByteBuffer;
+			if (attachmentOrByteBufferField == null) {
+				attachmentBufferOrByteBuffer = null;
+			} else {
+				Object attachedObjectOrByteBuffer;
+				final boolean attachedObjectOrByteBufferFieldWasAccessible = attachmentOrByteBufferField.isAccessible();
+				try {
+					attachmentOrByteBufferField.setAccessible(true);
+					attachedObjectOrByteBuffer = attachmentOrByteBufferField.get(buffer);
+				} catch (IllegalArgumentException | IllegalAccessException iae) {
+					attachedObjectOrByteBuffer = null;
+				} finally {
+					attachmentOrByteBufferField.setAccessible(attachedObjectOrByteBufferFieldWasAccessible);
+				}
+				if (attachedObjectOrByteBuffer instanceof Buffer) {
+					attachmentBufferOrByteBuffer = (Buffer) attachedObjectOrByteBuffer;
+				} else {
+					attachmentBufferOrByteBuffer = null;
+				}
+			}
+			// if there is no buffer inside the buffer given in input
+			if (attachmentBufferOrByteBuffer == null) {// if it's a direct byte
+															// buffer and if it's an
+														// instance of
+														// a deallocatable buffer
+														// class
+				if (buffer instanceof ByteBuffer && deallocatableBufferClassSet.contains(bufferClass)) {
+					deallocatableDirectByteBuffer = (ByteBuffer) buffer;
+				} else {// it's not a byte buffer or it's not a
+							// deallocatable buffer
+					deallocatableDirectByteBuffer = null;
+					final String bufferClassName = bufferClass.getName();
+					logger.warning("No deallocatable buffer has been found for an instance of the class " + bufferClassName + " whereas it is a direct NIO buffer");
+				}
+			} else {// the passed buffer contains another buffer, looks for a
+						// deallocatable buffer inside it
+				deallocatableDirectByteBuffer = findDeallocatableBuffer(attachmentBufferOrByteBuffer);
+			}
+		} else {// there is no need to clean the heap based buffers
+			deallocatableDirectByteBuffer = null;
+		}
+		return deallocatableDirectByteBuffer;
+	}
+
+	public void deallocate(final Buffer buffer) {
+		if (deallocator != null) {
+			final ByteBuffer deallocatableBuffer = findDeallocatableBuffer(buffer);
+			if (deallocatableBuffer != null) {
+				deallocator.run(deallocatableBuffer);
+			}
+		}
+	}
+
+	public Deallocator getDeallocator() {
+		return (deallocator);
+	}
+
+	public void setDeallocator(Deallocator deallocator) {
+		this.deallocator = deallocator;
+	}
+
+	public Map<Class<?>, Field> getAttachmentOrByteBufferFieldMap() {
+		return (attachmentOrByteBufferFieldMap);
+	}
+
+	public void setAttachmentOrByteBufferFieldMap(Map<Class<?>, Field> attachmentOrByteBufferFieldMap) {
+		this.attachmentOrByteBufferFieldMap = attachmentOrByteBufferFieldMap;
+	}
+
+	public Set<Class<?>> getDeallocatableBufferClassSet() {
+		return (deallocatableBufferClassSet);
+	}
+
+	public void setDeallocatableBufferClassSet(Set<Class<?>> deallocatableBufferClassSet) {
+		this.deallocatableBufferClassSet = deallocatableBufferClassSet;
+	}
+}

src/org/warp/picalculator/gui/graphicengine/gpu/GPUDisplay.java

@@ -1,23 +1,28 @@
 package org.warp.picalculator.gui.graphicengine.gpu;
 
-import java.awt.image.BufferedImage;
+import java.io.IOException;
 
 import org.warp.picalculator.Main;
 import org.warp.picalculator.Utils;
 import org.warp.picalculator.gui.graphicengine.Drawable;
-import org.warp.picalculator.gui.graphicengine.Renderer;
+import org.warp.picalculator.gui.graphicengine.RAWFont;
+import org.warp.picalculator.gui.graphicengine.RAWSkin;
+
+import com.jogamp.opengl.GLProfile;
+import com.jogamp.opengl.egl.EGL;
 
 public class GPUDisplay implements org.warp.picalculator.gui.graphicengine.Display {
 
-	private boolean initialized = false;
+	private volatile boolean initialized = false;
-	private CalculatorWindow wnd;
+	private volatile boolean created = false;
+	private NEWTWindow wnd;
 	private Drawable d;
 	private GPURenderer r;
+	int[] size = new int[]{Main.screenSize[0], Main.screenSize[1]};
 
 	@Override
 	public int[] getSize() {
-		// TODO Auto-generated method stub
+		return size;
-		return null;
 	}
 
 	@Override
@@ -27,8 +32,7 @@ public class GPUDisplay implements org.warp.picalculator.gui.graphicengine.Displ
 
 	@Override
 	public void setTitle(String title) {
-		// TODO Auto-generated method stub
+		wnd.window.setTitle(title);
-		
 	}
 
 	@Override
@@ -38,59 +42,59 @@ public class GPUDisplay implements org.warp.picalculator.gui.graphicengine.Displ
 		}
 		wnd.window.setResizable(r);
 		wnd.window.setUndecorated(!r);
-        wnd.window.setPointerVisible(r);
+		wnd.window.setPointerVisible(r);
 	}
 
 	@Override
 	public void setDisplayMode(int ww, int wh) {
+		this.size[0] = ww;
+		this.size[1] = wh;
 		wnd.window.setSize(ww, wh);
 	}
 
 	@Override
 	public void create() {
+		created = true;
 		r = new GPURenderer();
-		wnd = new CalculatorWindow(this);
+		wnd = new NEWTWindow(this);
 		wnd.create();
 		setDisplayMode(Main.screenSize[0], Main.screenSize[1]);
-		setResizable(Utils.debugOn&!Utils.debugThirdScreen);
+		setResizable(Utils.debugOn & !Utils.debugThirdScreen);
 		initialized = true;
 	}
 
 	@Override
 	public boolean wasResized() {
-		// TODO Auto-generated method stub
+		return Main.screenSize[0] != size[0] | Main.screenSize[1] != size[1];
-		return false;
 	}
 
 	@Override
 	public int getWidth() {
-		// TODO Auto-generated method stub
+		return size[0];
-		return 0;
 	}
 
 	@Override
 	public int getHeight() {
-		// TODO Auto-generated method stub
+		return size[1];
-		return 0;
 	}
 
 	@Override
 	public void destroy() {
-//		EGL.destroy(); (Automatic)
+		initialized = false;
+		created = false;
+		wnd.window.destroy();
 	}
 
 	@Override
 	public void start(Drawable d) {
-        this.d = d;
+		this.d = d;
-        wnd.window.setVisible(true);
+		wnd.window.setVisible(true);
 	}
 
 	@Override
 	public void repaint() {
-		if (d != null) {
+		if (d != null & r != null && r.gl != null) {
-			r.gl.glClearColor(red, green, blue, alpha);
 			d.refresh();
-			r.glFlush();
 		}
 	}
 
@@ -99,4 +103,30 @@ public class GPUDisplay implements org.warp.picalculator.gui.graphicengine.Displ
 		return r;
 	}
 
+	@Override
+	public RAWFont loadFont(String file) throws IOException {
+		return new GPUFont(file);
+	}
+
+	@Override
+	public RAWSkin loadSkin(String file) throws IOException {
+		return new GPUSkin(file);
+	}
+
+	@Override
+	public void waitUntilExit() {
+		try {
+			do {
+				Thread.sleep(500);
+			} while(initialized | created);
+		} catch (InterruptedException e) {
+			
+		}
+	}
+
+	@Override
+	public boolean isSupported() {
+		return GLProfile.isAnyAvailable() == false;
+	}
+
 }

src/org/warp/picalculator/gui/graphicengine/gpu/GPUFont.java

@@ -0,0 +1,140 @@
+package org.warp.picalculator.gui.graphicengine.gpu;
+
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.IOException;
+
+import javax.imageio.ImageIO;
+
+import org.warp.picalculator.gui.graphicengine.Display;
+import org.warp.picalculator.gui.graphicengine.RAWFont;
+import org.warp.picalculator.gui.graphicengine.cpu.CPUFont;
+
+import com.jogamp.opengl.GLException;
+import com.jogamp.opengl.util.texture.Texture;
+
+public class GPUFont implements RAWFont {
+
+	public Texture texture;
+	public int textureW;
+	public int textureH;
+	public int charW;
+	public int charH;
+	public int minCharIndex;
+	public int maxCharIndex;
+
+	public int memoryWidth;
+	public int memoryHeight;
+	public int memoryWidthOfEachColumn;
+
+	private boolean initialized = false;
+	private CPUFont tmpFont;
+
+	GPUFont(String file) throws IOException {
+		load(file);
+	}
+
+	@Override
+	public void load(String file) throws IOException {
+		CPUFont font = CPUFont.loadTemporaryFont(file);
+		charW = font.charW;
+		charH = font.charH;
+		minCharIndex = font.minBound;
+		maxCharIndex = font.maxBound;
+		tmpFont = font;
+		font = null;
+	}
+	
+	public int[] getCharIndexes(String txt) {
+		final int l = txt.length();
+		final int[] indexes = new int[l];
+		final char[] chars = txt.toCharArray();
+		for (int i = 0; i < l; i++) {
+			indexes[i] = (chars[i] & 0xFFFF) - minCharIndex;
+		}
+		return indexes;
+	}
+
+	private void genTexture(boolean[][] chars) {
+		final double totalChars = maxCharIndex - minCharIndex;
+		final int w = powerOf2((int) (Math.ceil(Math.sqrt(totalChars) * charW)));
+		final int h = powerOf2((int) (Math.ceil(Math.sqrt(totalChars) * charH)));
+		final int maxIndexW = (int) Math.floor(((double) w) / ((double) charW)) - 1;
+		BufferedImage bfi = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
+		int indexX = 0;
+		int indexY = 0;
+		for (int i = 0; i < totalChars; i++) {
+			boolean[] currentChar = chars[i];
+			if (currentChar != null && currentChar.length > 0) {
+				for (int charY = 0; charY < charH; charY++) {
+					for (int charX = 0; charX < charW; charX++) {
+						if (currentChar[charY*charW+charX]) {
+							bfi.setRGB(indexX * charW + charX, indexY * charH + charY, 0xFFFFFFFF);
+						}
+					}
+				}
+			}
+			indexX++;
+			if (indexX >= maxIndexW) {
+				indexX = 0;
+				indexY += 1;
+			}
+			currentChar = null;
+		}
+		try {
+			memoryWidth = w;
+			memoryHeight = h;
+			memoryWidthOfEachColumn = maxIndexW;
+			texture = GPURenderer.importTexture(bfi);
+			textureW = bfi.getWidth();
+			textureH = bfi.getHeight();
+			bfi.flush();
+			bfi = null;
+		} catch (GLException | IOException e) {
+			e.printStackTrace();
+		}
+	}
+
+	private int powerOf2(int a) {
+		return (int) (a == 0 ? 0 : Math.pow(2, 32 - Integer.numberOfLeadingZeros(a - 1)));
+	}
+
+	@Override
+	public void initialize(Display d) {
+		genTexture(tmpFont.rawchars);
+		tmpFont.chars32 = null;
+		tmpFont.rawchars = null;
+		tmpFont = null;
+		initialized = true;
+	}
+
+	@Override
+	public void use(Display d) {
+		if (!initialized) {
+			initialize(d);
+		}
+		final GPURenderer r = (GPURenderer) d.getRenderer();
+		r.currentFont = this;
+		r.useTexture(texture, textureW, textureH);
+	}
+
+	@Override
+	public int getStringWidth(String text) {
+		final int w = (charW + 1) * text.length();
+		if (text.length() > 0) {
+			return w - 1;
+		} else {
+			return 0;
+		}
+	}
+
+	@Override
+	public int getCharacterWidth() {
+		return charW;
+	}
+
+	@Override
+	public int getCharacterHeight() {
+		return charH;
+	}
+}

src/org/warp/picalculator/gui/graphicengine/gpu/GPURenderer.java

@@ -2,123 +2,261 @@ package org.warp.picalculator.gui.graphicengine.gpu;
 
 import java.awt.FontMetrics;
 import java.awt.image.BufferedImage;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.Buffer;
+import java.nio.FloatBuffer;
+import javax.imageio.ImageIO;
 
 import org.warp.picalculator.gui.graphicengine.RAWFont;
 import org.warp.picalculator.gui.graphicengine.Renderer;
 
-import com.jogamp.opengl.GL2ES2;
+import com.jogamp.common.nio.Buffers;
+import com.jogamp.opengl.GL;
+import com.jogamp.opengl.GL2ES1;
+import com.jogamp.opengl.GLException;
+import com.jogamp.opengl.util.texture.Texture;
+import com.jogamp.opengl.util.texture.TextureData;
+import com.jogamp.opengl.util.texture.TextureIO;
 
 public class GPURenderer implements Renderer {
 
-	public GL2ES2 gl;
+	public GL2ES1 gl;
+
+	private final DeallocationHelper deallocationHelper = new DeallocationHelper();
+	FloatBuffer fbVertices;
+	FloatBuffer txVertices;
+	FloatBuffer colVertices;
+	int fbElements;
+
+	float[] currentColor = new float[16];
+	float[] currentClearColorARGBf = new float[]{1f, 197f/255f, 194f/255f, 175f/255f};
+	boolean currentTexEnabled;
+	Texture currentTex;
+	float currentTexWidth;
+	float currentTexHeight;
+	
+	GPUFont currentFont;
 
 	@Override
 	public void glColor3i(int r, int gg, int b) {
-		// TODO Auto-generated method stub
+		final float red = ((float)r) / 255f;
-		
+		final float gre = ((float)gg) / 255f;
+		final float blu = ((float)b) / 255f;
+		currentColor = new float[] { red, gre, blu, 1.0f, red, gre, blu, 1.0f, red, gre, blu, 1.0f, red, gre, blu, 1.0f, };
 	}
 
 	@Override
-	public void glColor(int c) {
+	public void glColor3f(float red, float gre, float blu) {
-		// TODO Auto-generated method stub
+		currentColor = new float[] { red, gre, blu, 1.0f, red, gre, blu, 1.0f, red, gre, blu, 1.0f, red, gre, blu, 1.0f, };
+	}
 
+	@Override
+	public void glColor4f(float red, float gre, float blu, float alp) {
+		currentColor = new float[] { red, gre, blu, alp, red, gre, blu, alp, red, gre, blu, alp, red, gre, blu, alp, };
+	}
+
+	@Override
+	public void glColor(int rgb) {
+		final int alpha = (rgb >> 24) & 0xFF;
+		final int red = (rgb >> 16) & 0xFF;
+		final int green = (rgb >> 8) & 0xFF;
+		final int blue = rgb & 0xFF;
+		glColor4i(red, green, blue, alpha);
 	}
 
 	@Override
 	public int glGetClearColor() {
-		// TODO Auto-generated method stub
+		return (int)(currentClearColorARGBf[0] * 255)  << 24 | (int)(currentClearColorARGBf[1] * 255) << 16 | (int)(currentClearColorARGBf[2] * 255) << 8 | (int)(currentClearColorARGBf[3] * 255);
-		return 0;
 	}
 
 	@Override
-	public void glClearColor(int c) {
+	public void glClearColor(int rgb) {
-		// TODO Auto-generated method stub
+		final float alpha = (float)((rgb >> 24) & 0xFF) / 255f;
-		
+		final float red = (float)((rgb >> 16) & 0xFF) / 255f;
+		final float green = (float)((rgb >> 8) & 0xFF) / 255f;
+		final float blue = (float)(rgb & 0xFF) / 255f;
+		glClearColor4f(red, green, blue, alpha);
 	}
 
 	@Override
-	public void glColor4i(int red, int green, int blue, int alpha) {
+	public void glColor4i(int r, int g, int b, int a) {
-		// TODO Auto-generated method stub
+		final float red = (r) / 255f;
-		
+		final float gre = (g) / 255f;
+		final float blu = (b) / 255f;
+		final float alp = (a) / 255f;
+		currentColor = new float[] { red, gre, blu, alp, red, gre, blu, alp, red, gre, blu, alp, red, gre, blu, alp, };
 	}
 
 	@Override
-	public void glClearColor(int red, int green, int blue, int alpha) {
+	public void glClearColor4i(int red, int green, int blue, int alpha) {
-		// TODO Auto-generated method stub
+		final float ros = (red) / 255f;
-		
+		final float gre = (green) / 255f;
+		final float blu = (blue) / 255f;
+		final float alp = (alpha) / 255f;
+		currentClearColorARGBf = new float[]{alp, ros, gre, blu};
 	}
 
 	@Override
-	public void glClear() {
+	public void glClearColor4f(float red, float green, float blue, float alpha) {
-		// TODO Auto-generated method stub
+		currentClearColorARGBf = new float[]{alpha, red, green, blue};
-		
 	}
 
 	@Override
-	public void glDrawSkin(int skinwidth, int[] skin, int x0, int y0, int s0, int t0, int s1, int t1,
+	public void glClear(int screenWidth, int screenHeight) {
-			boolean transparent) {
+		glColor(glGetClearColor());
-		// TODO Auto-generated method stub
+		glFillColor(0, 0, screenWidth, screenHeight);
-		
 	}
 
 	@Override
 	public void glDrawLine(int x0, int y0, int x1, int y1) {
-		// TODO Auto-generated method stub
+		glFillColor(x0, y0, x1-x0+1, y1-y0+1);
-		
 	}
 
 	@Override
-	public void glFillRect(int x0, int y0, int w1, int h1) {
+	public void glFillRect(int x, int y, int width, int height, float uvX, float uvY, float uvWidth, float uvHeight) {
-		// TODO Auto-generated method stub
+		enableTexture();
-		
+		uvWidth/=currentTexWidth;
+		uvX/=currentTexWidth;
+		uvHeight/=currentTexHeight;
+		uvY = 1 - uvY/currentTexHeight - uvHeight;
+		final float[] vertices = { x, y, 0.0f, x, y + height, 0.0f, x + width, y, 0.0f, x + width, y + height, 0.0f, };
+		final float[] tex_vertices = { uvX, uvY + uvHeight, uvX, uvY, uvX + uvWidth, uvY + uvHeight, uvX + uvWidth, uvY, };
+		fbElements++;
+		fbVertices.put(vertices);
+		txVertices.put(tex_vertices);
+		colVertices.put(currentColor);
 	}
 
 	@Override
-	public int[] getMatrixOfImage(BufferedImage bufferedImage) {
+	public void glFillColor(int x0, int y0, int w1, int h1) {
-		// TODO Auto-generated method stub
+		disableTexture();
-		return null;
+		final float[] vertices = { x0, y0, 0.0f, x0, y0 + h1, 0.0f, x0 + w1, y0, 0.0f, x0 + w1, y0 + h1, 0.0f, };
+		final float[] tex_vertices = { 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, 0.0f, };
+		fbElements++;
+		fbVertices.put(vertices);
+		txVertices.put(tex_vertices);
+		colVertices.put(currentColor);
 	}
 
 	@Override
 	public void glDrawStringLeft(int x, int y, String text) {
-		// TODO Auto-generated method stub
+		final int txtLen = text.length();
-		
+		int[] txtArray = currentFont.getCharIndexes(text);
+		int tableIndexX;
+		int tableIndexY;
+		for (int currentCharIndex = 0; currentCharIndex < txtLen; currentCharIndex++) {
+			tableIndexX = txtArray[currentCharIndex] % currentFont.memoryWidthOfEachColumn;
+			tableIndexY = (txtArray[currentCharIndex] - tableIndexX) / currentFont.memoryWidthOfEachColumn;
+			glFillRect(x + currentCharIndex * (currentFont.charW + 1), y, currentFont.charW, currentFont.charH, tableIndexX*currentFont.charW, tableIndexY*currentFont.charH, currentFont.charW, currentFont.charH);
+		}
 	}
 
 	@Override
 	public void glDrawStringCenter(int x, int y, String text) {
-		// TODO Auto-generated method stub
+		glDrawStringLeft(x - (currentFont.getStringWidth(text) / 2), y, text);
-		
 	}
 
 	@Override
 	public void glDrawStringRight(int x, int y, String text) {
-		// TODO Auto-generated method stub
+		glDrawStringLeft(x - currentFont.getStringWidth(text), y, text);
-		
-	}
-
-	@Override
-	public void glSetFont(RAWFont font) {
-		// TODO Auto-generated method stub
-		
-	}
-
-	@Override
-	public int glGetStringWidth(RAWFont rf, String text) {
-		// TODO Auto-generated method stub
-		return 0;
-	}
-
-	@Override
-	public int glGetFontWidth(FontMetrics fm, String text) {
-		// TODO Auto-generated method stub
-		return 0;
 	}
 
 	@Override
 	public RAWFont getCurrentFont() {
-		// TODO Auto-generated method stub
+		return currentFont;
-		return null;
 	}
 
+	static Texture importTexture(GL gl, String string) throws IOException {
+		final FileInputStream f = new FileInputStream("test.png");
+		final TextureData tx_dat = TextureIO.newTextureData(gl.getGLProfile(), f, false, TextureIO.PNG);
+		final Texture tex = new Texture(gl, tx_dat);
+		tex.setTexParameteri(gl, GL.GL_TEXTURE_MIN_FILTER, GL.GL_LINEAR);
+		tex.setTexParameteri(gl, GL.GL_TEXTURE_MAG_FILTER, GL.GL_NEAREST);
+		tex.setTexParameteri(gl, GL.GL_TEXTURE_WRAP_S, GL.GL_CLAMP_TO_EDGE);
+		tex.setTexParameteri(gl, GL.GL_TEXTURE_WRAP_T, GL.GL_CLAMP_TO_EDGE);
+		return tex;
+	}
+
+	static BufferedImage openTexture(String file) throws GLException, IOException {
+		final ByteArrayOutputStream os = new ByteArrayOutputStream();
+		return ImageIO.read(GPURenderer.class.getClassLoader().getResource(file));
+	}
+
+	static Texture importTexture(BufferedImage img) throws GLException, IOException {
+		final ByteArrayOutputStream os = new ByteArrayOutputStream();
+		ImageIO.write(img, "png", os);
+		final InputStream fis = new ByteArrayInputStream(os.toByteArray());
+		return TextureIO.newTexture(fis, false, TextureIO.PNG);
+	}
+
+	@Override
+	public void glClearSkin() {
+		if (currentTex != null) {
+			currentTex = null;
+			endDrawCycle();
+			startDrawCycle();
+		}
+	}
+
+	public void startDrawCycle() {
+		fbVertices = Buffers.newDirectFloatBuffer(3 * 4);
+		txVertices = Buffers.newDirectFloatBuffer(2 * 4);
+		colVertices = Buffers.newDirectFloatBuffer(4 * 4);
+		fbElements = 0;
+	}
+
+	public void endDrawCycle() {
+		fbVertices.rewind();
+		txVertices.rewind();
+		colVertices.rewind();
+
+		gl.glColorPointer(4, GL.GL_FLOAT, 0, colVertices);
+		gl.glTexCoordPointer(2, GL.GL_FLOAT, 0, txVertices);
+		gl.glVertexPointer(3, GL.GL_FLOAT, 0, fbVertices);
+
+		if (currentTexEnabled) {
+			gl.glEnable(GL2ES1.GL_TEXTURE_2D);
+			currentTex.bind(gl);
+		} else {
+			gl.glDisable(GL2ES1.GL_TEXTURE_2D);
+		}
+
+		gl.glDrawArrays(GL.GL_TRIANGLE_STRIP, 0, 4);
+
+		deleteBuffer(fbVertices);
+		deleteBuffer(txVertices);
+		deleteBuffer(colVertices);
+		fbVertices = null;
+		txVertices = null;
+		colVertices = null;
+	}
+
+	public void deleteBuffer(final Buffer realNioBuffer) {
+		if (deallocationHelper != null) {
+			deallocationHelper.deallocate(realNioBuffer);
+		}
+	}
+
+	void disableTexture() {
+		endDrawCycle();
+		startDrawCycle();
+		currentTexEnabled = false;
+	}
+
+	void enableTexture() {
+		endDrawCycle();
+		startDrawCycle();
+		currentTexEnabled = true;
+	}
+
+	void useTexture(Texture t, float w, float h) {
+		enableTexture();
+		currentTex = t;
+		currentTexWidth = w;
+		currentTexHeight = h;
+	}
 }

src/org/warp/picalculator/gui/graphicengine/gpu/GPUSkin.java

@@ -0,0 +1,58 @@
+package org.warp.picalculator.gui.graphicengine.gpu;
+
+import java.awt.image.BufferedImage;
+import java.io.IOException;
+import org.warp.picalculator.gui.graphicengine.Display;
+import org.warp.picalculator.gui.graphicengine.RAWSkin;
+
+import com.jogamp.opengl.GL2ES1;
+import com.jogamp.opengl.GLException;
+import com.jogamp.opengl.util.texture.Texture;
+
+public class GPUSkin implements RAWSkin {
+
+	public Texture t;
+	public int w;
+	public int h;
+
+	private String texturePath;
+	private boolean initialized = false;
+
+	GPUSkin(String file) throws IOException {
+		load(file);
+	}
+
+	@Override
+	public void load(String file) throws IOException {
+		if ((this.getClass().getClassLoader().getResource(file)) == null) {
+			throw new IOException("File '" + file + "' not found!");
+		}
+		texturePath = file;
+	}
+
+	@Override
+	public void initialize(Display d) {
+		try {
+			BufferedImage i = GPURenderer.openTexture(texturePath);
+			GL2ES1 gl = ((GPURenderer)d.getRenderer()).gl;
+			t = GPURenderer.importTexture(i);
+			w = i.getWidth();
+			h = i.getHeight();
+			t.setTexParameteri(gl, GL2ES1.GL_TEXTURE_MAG_FILTER, GL2ES1.GL_NEAREST);
+			initialized = true;
+		} catch (GLException | IOException e) {
+			e.printStackTrace();
+			System.exit(1);
+		}
+	}
+
+	@Override
+	public void use(Display d) {
+		if (!initialized) {
+			initialize(d);
+		}
+		final GPURenderer r = (GPURenderer) d.getRenderer();
+		r.useTexture(t,w,h);
+	}
+
+}

src/org/warp/picalculator/gui/graphicengine/gpu/NEWTWindow.java

@@ -0,0 +1,381 @@
+/**
+ * Copyright 2012-2013 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ *    1. Redistributions of source code must retain the above copyright notice, this list of
+ *       conditions and the following disclaimer.
+ *
+ *    2. Redistributions in binary form must reproduce the above copyright notice, this list
+ *       of conditions and the following disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+
+package org.warp.picalculator.gui.graphicengine.gpu;
+
+import com.jogamp.opengl.GL;
+import com.jogamp.opengl.GL2ES1;
+import com.jogamp.opengl.GLAutoDrawable;
+import com.jogamp.opengl.GLEventListener;
+import com.jogamp.opengl.GLProfile;
+import com.jogamp.opengl.fixedfunc.GLMatrixFunc;
+import com.jogamp.opengl.fixedfunc.GLPointerFunc;
+import com.jogamp.opengl.GLCapabilities;
+import com.jogamp.newt.event.KeyEvent;
+import com.jogamp.newt.event.KeyListener;
+import com.jogamp.newt.event.WindowEvent;
+import com.jogamp.newt.event.WindowListener;
+import com.jogamp.newt.event.WindowUpdateEvent;
+import com.jogamp.newt.opengl.GLWindow;
+
+import com.jogamp.opengl.util.*;
+
+import java.awt.event.ComponentEvent;
+import java.awt.event.ComponentListener;
+
+import org.warp.picalculator.device.Keyboard;
+import org.warp.picalculator.device.Keyboard.Key;
+import org.warp.picalculator.gui.DisplayManager;
+import org.warp.picalculator.gui.graphicengine.Display;
+
+/**
+ * <pre>
+ *   __ __|_  ___________________________________________________________________________  ___|__ __
+ *  //    /\                                           _                                  /\    \\
+ * //____/  \__     __ _____ _____ _____ _____ _____  | |     __ _____ _____ __        __/  \____\\
+ *  \    \  / /  __|  |     |   __|  _  |     |  _  | | |  __|  |     |   __|  |      /\ \  /    /
+ *   \____\/_/  |  |  |  |  |  |  |     | | | |   __| | | |  |  |  |  |  |  |  |__   "  \_\/____/
+ *  /\    \     |_____|_____|_____|__|__|_|_|_|__|    | | |_____|_____|_____|_____|  _  /    /\
+ * /  \____\                       http://jogamp.org  |_|                              /____/  \
+ * \  /   "' _________________________________________________________________________ `"   \  /
+ *  \/____.                                                                             .____\/
+ * </pre>
+ *
+ * <p>
+ * JOGL2 OpenGL ES 2 demo to expose and learn what the RAW OpenGL ES 2 API looks
+ * like.
+ *
+ * Compile, run and enjoy:
+ * wget
+ * http://jogamp.org/deployment/jogamp-current/archive/jogamp-all-platforms.7z
+ * 7z x jogamp-all-platforms.7z
+ * cd jogamp-all-platforms
+ * mkdir -p demos/es2
+ * cd demos/es2
+ * wget
+ * https://raw.github.com/xranby/jogl-demos/master/src/demos/es2/RawGL2ES1demo.java
+ * cd ../..
+ * javac -cp jar/jogl-all.jar:jar/gluegen-rt.jar demos/es2/RawGL2ES1demo.java
+ * java -cp jar/jogl-all.jar:jar/gluegen-rt.jar:. demos.es2.RawGL2ES1demo
+ * </p>
+ *
+ *
+ * @author Xerxes Rånby (xranby)
+ */
+
+public class NEWTWindow implements GLEventListener {
+
+	private final GPUDisplay disp;
+	private final GPURenderer renderer;
+
+	public NEWTWindow(GPUDisplay disp) {
+		this.disp = disp;
+		renderer = disp.getRenderer();
+	}
+
+	public GLWindow window;
+
+	public void create() {
+		/* This demo are based on the GL2ES1 GLProfile that uses common hardware acceleration
+		 * functionality of desktop OpenGL 3, 2 and mobile OpenGL ES 2 devices.
+		 * JogAmp JOGL will probe all the installed libGL.so, libEGL.so and libGLESv2.so librarys on
+		 * the system to find which one provide hardware acceleration for your GPU device.
+		 * Its common to find more than one version of these librarys installed on a system.
+		 * For example on a ARM Linux system JOGL may find
+		 * Hardware accelerated Nvidia tegra GPU drivers in: /usr/lib/nvidia-tegra/libEGL.so
+		 * Software rendered Mesa Gallium driver in: /usr/lib/arm-linux-gnueabi/mesa-egl/libEGL.so.1
+		 * Software rendered Mesa X11 in: /usr/lib/arm-linux-gnueabi/mesa/libGL.so
+		 * Good news!: JOGL does all this probing for you all you have to do are to ask for
+		 * the GLProfile you want to use.
+		 */
+
+		System.out.println("Loading OpenGL...");
+		System.out.println(GLProfile.glAvailabilityToString());
+		if (GLProfile.isAnyAvailable()) {
+			System.err.println("Le OpenGL non sono presenti su questo computer!");
+		}
+		final GLCapabilities caps = new GLCapabilities(GLProfile.get(GLProfile.GL2ES1));
+		System.out.println("Loaded OpenGL");
+		// We may at this point tweak the caps and request a translucent drawable
+		caps.setBackgroundOpaque(true); //transparency window
+		final GLWindow glWindow = GLWindow.create(caps);
+		window = glWindow;
+
+		glWindow.setTitle("Algebraic Calculator for Raspberry PI by Andrea Cavalli (XDrake99)");
+		
+		glWindow.addWindowListener(new WindowListener() {
+
+			@Override
+			public void windowDestroyNotify(WindowEvent e) {
+				// TODO Auto-generated method stub
+				
+			}
+
+			@Override
+			public void windowDestroyed(WindowEvent e) {
+				DisplayManager.display.destroy();
+			}
+
+			@Override
+			public void windowGainedFocus(WindowEvent e) {
+				// TODO Auto-generated method stub
+				
+			}
+
+			@Override
+			public void windowLostFocus(WindowEvent e) {
+				// TODO Auto-generated method stub
+				
+			}
+
+			@Override
+			public void windowMoved(WindowEvent e) {
+				// TODO Auto-generated method stub
+				
+			}
+
+			@Override
+			public void windowRepaint(WindowUpdateEvent e) {
+				// TODO Auto-generated method stub
+				
+			}
+
+			@Override
+			public void windowResized(WindowEvent e) {
+				
+			}
+			
+		});
+		glWindow.addKeyListener(new KeyListener() {
+			@Override
+			public void keyPressed(KeyEvent arg0) {
+				Keyboard.debugKeyCode = arg0.getKeyCode();
+			}
+
+			@Override
+			public void keyReleased(KeyEvent arg0) {
+				switch (arg0.getKeyCode()) {
+					case KeyEvent.VK_ESCAPE:
+						Keyboard.keyReleased(Key.POWER);
+						break;
+					case KeyEvent.VK_D:
+						Keyboard.keyReleased(Key.debug_DEG);
+						break;
+					case KeyEvent.VK_R:
+						Keyboard.keyReleased(Key.debug_RAD);
+						break;
+					case KeyEvent.VK_G:
+						Keyboard.keyReleased(Key.debug_GRA);
+						break;
+					case KeyEvent.VK_X:
+						if (Keyboard.alpha) {
+							Keyboard.keyReleased(Key.LETTER_X);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case KeyEvent.VK_P:
+						if (Keyboard.alpha) {
+							Keyboard.keyReleased(Key.PI);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case KeyEvent.VK_B:
+						if (Keyboard.shift) {
+							Keyboard.keyReleased(Key.BRIGHTNESS_CYCLE_REVERSE);
+						} else if (!Keyboard.shift && !Keyboard.alpha) {
+							Keyboard.keyReleased(Key.BRIGHTNESS_CYCLE);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case KeyEvent.VK_ENTER:
+						if (!Keyboard.shift && !Keyboard.alpha) {
+							Keyboard.keyReleased(Key.SOLVE);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						int row = 2;
+						int col = 1;
+						Keyboard.debugKeysDown[row - 1][col - 1] = false;
+						break;
+					case KeyEvent.VK_1:
+						if (!Keyboard.shift && !Keyboard.alpha) {
+							Keyboard.keyReleased(Key.debug1);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case KeyEvent.VK_2:
+						if (!Keyboard.shift && !Keyboard.alpha) {
+							Keyboard.keyReleased(Key.debug2);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case KeyEvent.VK_3:
+						if (!Keyboard.shift && !Keyboard.alpha) {
+							Keyboard.keyReleased(Key.debug3);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case KeyEvent.VK_4:
+						if (!Keyboard.shift && !Keyboard.alpha) {
+							Keyboard.keyReleased(Key.debug4);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case KeyEvent.VK_5:
+						if (!Keyboard.shift && !Keyboard.alpha) {
+							Keyboard.keyReleased(Key.debug5);
+						} else {
+							Keyboard.keyReleased(Key.NONE);
+						}
+						break;
+					case 0x15:
+					case KeyEvent.VK_SHIFT:
+						Keyboard.keyReleased(Key.SHIFT);
+						break;
+					case KeyEvent.VK_A:
+						Keyboard.keyReleased(Key.ALPHA);
+						break;
+					case KeyEvent.VK_M:
+						Keyboard.keyPressed(Key.SURD_MODE);
+						break;
+					case KeyEvent.VK_LEFT:
+						//LEFT
+						row = 2;
+						col = 3;
+						Keyboard.debugKeysDown[row - 1][col - 1] = false;
+					case KeyEvent.VK_RIGHT:
+						//RIGHT
+						row = 2;
+						col = 5;
+						Keyboard.debugKeysDown[row - 1][col - 1] = false;
+				}
+			}
+		});
+
+		glWindow.addGLEventListener(this /* GLEventListener */);
+		final Animator animator = new Animator();
+		animator.add(glWindow);
+		animator.start();
+	}
+
+	@Override
+	public void init(GLAutoDrawable drawable) {
+		final GL2ES1 gl = drawable.getGL().getGL2ES1();
+
+		//Vsync
+		gl.setSwapInterval(2);
+		
+		//Textures
+		gl.glEnable(GL.GL_TEXTURE_2D);
+
+		//Transparency
+		gl.glEnable(GL2ES1.GL_BLEND);
+		gl.glBlendFunc(GL2ES1.GL_SRC_ALPHA, GL2ES1.GL_ONE_MINUS_SRC_ALPHA);
+		
+		try {
+			renderer.currentTex = ((GPUSkin) disp.loadSkin("test.png")).t;
+		} catch (final Exception e) {
+			e.printStackTrace();
+		}
+
+		System.err.println("Chosen GLCapabilities: " + drawable.getChosenGLCapabilities());
+		System.err.println("INIT GL IS: " + gl.getClass().getName());
+		System.err.println("GL_VENDOR: " + gl.glGetString(GL.GL_VENDOR));
+		System.err.println("GL_RENDERER: " + gl.glGetString(GL.GL_RENDERER));
+		System.err.println("GL_VERSION: " + gl.glGetString(GL.GL_VERSION));
+	}
+
+	@Override
+	public void reshape(GLAutoDrawable glad, int x, int y, int width, int height) {
+		disp.size[0] = width;
+		disp.size[1] = height;
+		final GL2ES1 gl = glad.getGL().getGL2ES1();
+		float max_wh, min_wh;
+		if (width == 0) {
+			width = 1;
+		}
+		if (height == 0) {
+			height = 1;
+		}
+		if (width > height) {
+			max_wh = width;
+			min_wh = height;
+		} else {
+			max_wh = height;
+			min_wh = width;
+		}
+
+		gl.glViewport(0, 0, width, height);
+
+		gl.glMatrixMode(GLMatrixFunc.GL_PROJECTION);
+		gl.glLoadIdentity();
+
+		gl.glOrtho(0.0, width, height, 0.0, -1, 1);
+
+		gl.glMatrixMode(GLMatrixFunc.GL_MODELVIEW);
+		gl.glLoadIdentity();
+	}
+
+	@Override
+	public void display(GLAutoDrawable glad) {
+		final GL2ES1 gl = glad.getGL().getGL2ES1();
+
+		renderer.gl = gl;
+
+		gl.glEnableClientState(GLPointerFunc.GL_COLOR_ARRAY);
+		gl.glEnableClientState(GLPointerFunc.GL_VERTEX_ARRAY);
+		gl.glEnableClientState(GLPointerFunc.GL_TEXTURE_COORD_ARRAY);
+
+		renderer.startDrawCycle();
+		
+		disp.repaint();
+
+		renderer.endDrawCycle();
+		
+		renderer.gl = null;
+
+		gl.glDisableClientState(GLPointerFunc.GL_COLOR_ARRAY);
+		gl.glDisableClientState(GLPointerFunc.GL_TEXTURE_COORD_ARRAY);
+		gl.glDisableClientState(GLPointerFunc.GL_VERTEX_ARRAY);
+	}
+
+	@Override
+	public void dispose(GLAutoDrawable drawable) {
+		System.out.println("cleanup");
+		final GL2ES1 gl = drawable.getGL().getGL2ES1();
+		System.exit(0);
+	}
+
+}

src/org/warp/picalculator/gui/screens/ChooseVariableValueScreen.java

@@ -1,15 +1,16 @@
 package org.warp.picalculator.gui.screens;
 
 import org.warp.picalculator.Main;
+import org.warp.picalculator.Utils;
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.functions.Function;
 import org.warp.picalculator.math.functions.Variable.VariableValue;
 
 public class ChooseVariableValueScreen extends Screen {
 
 	@SuppressWarnings("unused")
-	private MathInputScreen es;
+	private final MathInputScreen es;
 	public Function resultNumberValue;
 
 	public ChooseVariableValueScreen(MathInputScreen es, VariableValue variableValue) {
@@ -20,20 +21,28 @@ public class ChooseVariableValueScreen extends Screen {
 	}
 
 	@Override
-	public void created() throws InterruptedException {
+	public void created() throws InterruptedException {}
-	}
 
 	@Override
 	public void init() throws InterruptedException {}
 
 	@Override
 	public void render() {
-		PIDisplay.renderer.glColor4i(0, 0, 0, 64);
+		Utils.getFont(false, true).use(DisplayManager.display);
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2+1, Main.screenSize[1]/4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glColor4i(0, 0, 0, 64);
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2, Main.screenSize[1]/4+1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2 + 1, Main.screenSize[1] / 2 - 20, "WORK IN PROGRESS.");
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2+1, Main.screenSize[1]/4+1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2, Main.screenSize[1] / 2 - 20 + 1, "WORK IN PROGRESS.");
-		PIDisplay.renderer.glColor3i(255, 0, 0);
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2 + 1, Main.screenSize[1] / 2 - 20 + 1, "WORK IN PROGRESS.");
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2, Main.screenSize[1]/4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glColor3i(255, 0, 0);
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2, Main.screenSize[1] / 2 - 20, "WORK IN PROGRESS.");
+		
+		Utils.getFont(false, false).use(DisplayManager.display);
+		DisplayManager.renderer.glColor4i(0, 0, 0, 64);
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2 + 1, Main.screenSize[1] / 2, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2, Main.screenSize[1] / 2 + 1, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2 + 1, Main.screenSize[1] / 2 + 1, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glColor3i(255, 0, 0);
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2, Main.screenSize[1] / 2, "THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
 	}
 
 	@Override

src/org/warp/picalculator/gui/screens/KeyboardDebugScreen.java

@@ -1,12 +1,11 @@
 package org.warp.picalculator.gui.screens;
 
-import static org.warp.picalculator.device.graphicengine.cpu.CPUDisplay.Render.*;
+import static org.warp.picalculator.gui.DisplayManager.fonts;
-import static org.warp.picalculator.gui.PIDisplay.colore;
-import static org.warp.picalculator.gui.PIDisplay.fonts;
 
 import org.warp.picalculator.Main;
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
+import org.warp.picalculator.gui.graphicengine.Renderer;
 
 public class KeyboardDebugScreen extends Screen {
 
@@ -14,7 +13,7 @@ public class KeyboardDebugScreen extends Screen {
 	public String keyevent;
 	public static int keyX;
 	public static int keyY;
-	public static String[] log = new String[]{"POWER ON","LOADING","LOADED","DONE","---"};
+	public static String[] log = new String[] { "POWER ON", "LOADING", "LOADED", "DONE", "---" };
 	public long beforetime;
 
 	public KeyboardDebugScreen() {
@@ -23,141 +22,140 @@ public class KeyboardDebugScreen extends Screen {
 	}
 
 	@Override
-	public void created() throws InterruptedException {
+	public void created() throws InterruptedException {}
-	}
 
 	@Override
-	public void init() throws InterruptedException {
+	public void init() throws InterruptedException {}
-	}
 
 	@Override
 	public void render() {
-		PIDisplay.renderer.glSetFont(fonts[2]);
+		Renderer renderer = DisplayManager.renderer;
-		colore(0.75f, 0.0f, 0.0f, 1.0f);
+		fonts[2].use(DisplayManager.display);
-		PIDisplay.renderer.glDrawStringRight(Main.screenSize[0] - 10, 30, "-" + keyevent.toUpperCase() + "-");
+		renderer.glColor4f(0.75f, 0.0f, 0.0f, 1.0f);
+		renderer.glDrawStringRight(Main.screenSize[0] - 10, 30, "-" + keyevent.toUpperCase() + "-");
 		if (keyevent != "NONE") {
-			PIDisplay.renderer.glSetFont(fonts[2]);
+			fonts[2].use(DisplayManager.display);
-			colore(0.0f, 0.0f, 0.0f, 1.0f);
+			renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-			PIDisplay.renderer.glDrawStringLeft(10, 30, "Key position");
+			renderer.glDrawStringLeft(10, 30, "Key position");
-			PIDisplay.renderer.glDrawStringLeft(10, 45, "X: " + keyX + ", Y:" + keyY);
+			renderer.glDrawStringLeft(10, 45, "X: " + keyX + ", Y:" + keyY);
-			PIDisplay.renderer.glDrawStringLeft(10, 65, "Key value");
+			renderer.glDrawStringLeft(10, 65, "Key value");
-			PIDisplay.renderer.glDrawStringLeft(10, 80, key);
+			renderer.glDrawStringLeft(10, 80, key);
 		}
-		PIDisplay.renderer.glSetFont(fonts[3]);
+		fonts[3].use(DisplayManager.display);
-		colore(0.0f, 0.0f, 0.0f, 1.0f);
+		renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
 		for (int i = 0; i < 5; i++) {
 			if (log[i] != null) {
-				PIDisplay.renderer.glDrawStringLeft(10, 230 + 15*(i+1), log[i].toUpperCase());
+				renderer.glDrawStringLeft(10, 230 + 15 * (i + 1), log[i].toUpperCase());
 			}
 		}
 
 		//FROM SERIAL
-		colore(0.0f, 0.0f, 0.0f, 1.0f);
+		renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-		PIDisplay.renderer.glFillRect(-80+100+200, 90, 5, 5);
+		renderer.glFillColor(-80 + 100 + 200, 90, 5, 5);
-		PIDisplay.renderer.glFillRect(-80+100, 100, 200, 70);
+		renderer.glFillColor(-80 + 100, 100, 200, 70);
-		PIDisplay.renderer.glSetFont(fonts[2]);
+		fonts[2].use(DisplayManager.display);
-		colore(1.0f, 1.0f, 1.0f, 1.0f);
+		renderer.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
-		PIDisplay.renderer.glDrawStringCenter(-80+100+200/2, 100+70/2-(PIDisplay.renderer.getCurrentFont().charH/2), "FROM SERIAL");
+		renderer.glDrawStringCenter(-80 + 100 + 200 / 2, 100 + 70 / 2 - (renderer.getCurrentFont().getCharacterHeight() / 2), "FROM SERIAL");
-		PIDisplay.renderer.glSetFont(fonts[3]);
+		fonts[3].use(DisplayManager.display);
-		colore(0.0f, 0.0f, 1.0f, 1.0f);
+		renderer.glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
 		for (int i = 0; i < 8; i++) {
 			if (pinsA[i] == 1) {
-				colore(0.0f, 1.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 			} else if (pinsA[i] == 2) {
-				colore(0.5f, 0.5f, 1.0f, 1.0f);
+				renderer.glColor4f(0.5f, 0.5f, 1.0f, 1.0f);
 			} else if (pinsA[i] == -1) {
-				colore(0.7f, 0.7f, 0.7f, 1.0f);
+				renderer.glColor4f(0.7f, 0.7f, 0.7f, 1.0f);
 			} else if (pinsA[i] == 0) {
-				colore(1.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 			}
-			PIDisplay.renderer.glFillRect(-80+103+25*(7-i), 80, 20, 20);
+			renderer.glFillColor(-80 + 103 + 25 * (7 - i), 80, 20, 20);
-			colore(0.0f, 0.0f, 0.0f, 1.0f);
+			renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-			PIDisplay.renderer.glDrawStringCenter(-80+113+25*(7-i), 90-(PIDisplay.renderer.getCurrentFont().charH/2), ""+(i+1));
+			renderer.glDrawStringCenter(-80 + 113 + 25 * (7 - i), 90 - (renderer.getCurrentFont().getCharacterHeight() / 2), "" + (i + 1));
 		}
 		for (int i = 15; i >= 8; i--) {
 			if (pinsA[i] == 1) {
-				colore(0.0f, 1.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 			} else if (pinsA[i] == 2) {
-				colore(0.5f, 0.5f, 1.0f, 1.0f);
+				renderer.glColor4f(0.5f, 0.5f, 1.0f, 1.0f);
 			} else if (pinsA[i] == -1) {
-				colore(0.7f, 0.7f, 0.7f, 1.0f);
+				renderer.glColor4f(0.7f, 0.7f, 0.7f, 1.0f);
 			} else if (pinsA[i] == 0) {
-				colore(1.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 			}
-			PIDisplay.renderer.glFillRect(-80+103+25*(i-8), 170, 20, 20);
+			renderer.glFillColor(-80 + 103 + 25 * (i - 8), 170, 20, 20);
-			colore(0.0f, 0.0f, 0.0f, 1.0f);
+			renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-			PIDisplay.renderer.glDrawStringCenter(-80+113+25*(i-8), 180-(PIDisplay.renderer.getCurrentFont().charH/2), ""+(i+1));
+			renderer.glDrawStringCenter(-80 + 113 + 25 * (i - 8), 180 - (renderer.getCurrentFont().getCharacterHeight() / 2), "" + (i + 1));
 		}
 		for (int i = 0; i < 8; i++) {
 			if (dataA[i]) {
-				colore(0.0f, 1.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 			} else {
-				colore(1.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 			}
-			PIDisplay.renderer.glFillRect(-80+160+10*(i), 150, 8, 8);
+			renderer.glFillColor(-80 + 160 + 10 * (i), 150, 8, 8);
 		}
 
 		//TO SERIAL
-		colore(0.0f, 0.0f, 0.0f, 1.0f);
+		renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-		PIDisplay.renderer.glFillRect(150+90, 200, 5, 5);
+		renderer.glFillColor(150 + 90, 200, 5, 5);
-		PIDisplay.renderer.glFillRect(150+100, 100, 200, 70);
+		renderer.glFillColor(150 + 100, 100, 200, 70);
-		PIDisplay.renderer.glSetFont(fonts[2]);
+		fonts[2].use(DisplayManager.display);
-		colore(1.0f, 1.0f, 1.0f, 1.0f);
+		renderer.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
-		PIDisplay.renderer.glDrawStringCenter(150+100+200/2, 100+70/2-(PIDisplay.renderer.getCurrentFont().charH/2), "TO SERIAL");
+		renderer.glDrawStringCenter(150 + 100 + 200 / 2, 100 + 70 / 2 - (renderer.getCurrentFont().getCharacterHeight() / 2), "TO SERIAL");
-		PIDisplay.renderer.glSetFont(fonts[3]);
+		fonts[3].use(DisplayManager.display);
-		colore(0.0f, 0.0f, 1.0f, 1.0f);
+		renderer.glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
 		for (int i = 15; i >= 8; i--) {
 			if (pinsB[i] == 1) {
-				colore(0.0f, 1.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 			} else if (pinsB[i] == 2) {
-				colore(0.5f, 0.5f, 1.0f, 1.0f);
+				renderer.glColor4f(0.5f, 0.5f, 1.0f, 1.0f);
 			} else if (pinsB[i] == -1) {
-				colore(0.7f, 0.7f, 0.7f, 1.0f);
+				renderer.glColor4f(0.7f, 0.7f, 0.7f, 1.0f);
 			} else if (pinsB[i] == 0) {
-				colore(1.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 			}
-			PIDisplay.renderer.glFillRect(150+103+25*(15-i), 80, 20, 20);
+			renderer.glFillColor(150 + 103 + 25 * (15 - i), 80, 20, 20);
-			colore(0.0f, 0.0f, 0.0f, 1.0f);
+			renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-			PIDisplay.renderer.glDrawStringCenter(150+113+25*(15-i), 90-(PIDisplay.renderer.getCurrentFont().charH/2), ""+(i+1));
+			renderer.glDrawStringCenter(150 + 113 + 25 * (15 - i), 90 - (renderer.getCurrentFont().getCharacterHeight() / 2), "" + (i + 1));
 		}
 		for (int i = 7; i >= 0; i--) {
 			if (pinsB[i] == 1) {
-				colore(0.0f, 1.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 			} else if (pinsB[i] == 2) {
-				colore(0.5f, 0.5f, 1.0f, 1.0f);
+				renderer.glColor4f(0.5f, 0.5f, 1.0f, 1.0f);
 			} else if (pinsB[i] == -1) {
-				colore(0.7f, 0.7f, 0.7f, 1.0f);
+				renderer.glColor4f(0.7f, 0.7f, 0.7f, 1.0f);
 			} else if (pinsB[i] == 0) {
-				colore(1.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 			}
-			PIDisplay.renderer.glFillRect(150+103+25*(i), 170, 20, 20);
+			renderer.glFillColor(150 + 103 + 25 * (i), 170, 20, 20);
-			colore(0.0f, 0.0f, 0.0f, 1.0f);
+			renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-			PIDisplay.renderer.glDrawStringCenter(150+113+25*(i), 180-(PIDisplay.renderer.getCurrentFont().charH/2), ""+(i+1));
+			renderer.glDrawStringCenter(150 + 113 + 25 * (i), 180 - (renderer.getCurrentFont().getCharacterHeight() / 2), "" + (i + 1));
 		}
 		for (int i = 0; i < 8; i++) {
 			if (dataB[i]) {
-				colore(0.0f, 1.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 			} else {
-				colore(1.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 			}
-			PIDisplay.renderer.glFillRect(150+160+10*(i), 150, 8, 8);
+			renderer.glFillColor(150 + 160 + 10 * (i), 150, 8, 8);
 		}
 
 		//GPIO
 		for (int i = 0; i < 40; i++) {
 			if (gpio[i] == true) {
-				colore(0.0f, 1.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 			} else {
-				colore(1.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 			}
 			if (i % 2 == 0) {
-				PIDisplay.renderer.glFillRect(53+15*((i)/2), 50, 5, 5);
+				renderer.glFillColor(53 + 15 * ((i) / 2), 50, 5, 5);
-				colore(0.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-				PIDisplay.renderer.glDrawStringCenter(55+15*((i)/2), 60, ""+(i+1));
+				renderer.glDrawStringCenter(55 + 15 * ((i) / 2), 60, "" + (i + 1));
 			} else {
-				PIDisplay.renderer.glFillRect(53+15*((i-1)/2), 40, 5, 5);
+				renderer.glFillColor(53 + 15 * ((i - 1) / 2), 40, 5, 5);
-				colore(0.0f, 0.0f, 0.0f, 1.0f);
+				renderer.glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
-				PIDisplay.renderer.glDrawStringCenter(55+15*((i-1)/2), 35-PIDisplay.renderer.getCurrentFont().charH, ""+(i+1));
+				renderer.glDrawStringCenter(55 + 15 * ((i - 1) / 2), 35 - renderer.getCurrentFont().getCharacterHeight(), "" + (i + 1));
 			}
 		}
 
@@ -165,18 +163,18 @@ public class KeyboardDebugScreen extends Screen {
 		for (int c = 0; c < 8; c++) {
 			for (int r = 0; r < 8; r++) {
 				if (ks[c][r]) {
-					colore(0.0f, 1.0f, 0.0f, 1.0f);
+					renderer.glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
 				} else {
-					colore(1.0f, 0.0f, 0.0f, 1.0f);
+					renderer.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
 				}
-				PIDisplay.renderer.glFillRect(250+6*c, 250+6*r, 5, 5);
+				renderer.glFillColor(250 + 6 * c, 250 + 6 * r, 5, 5);
 			}
 		}
 	}
 
 	@Override
 	public void beforeRender(float dt) {
-		if (System.currentTimeMillis()-beforetime >= 1000) {
+		if (System.currentTimeMillis() - beforetime >= 1000) {
 			keyevent = "NONE";
 			keyX = 0;
 			keyY = 0;
@@ -209,18 +207,17 @@ public class KeyboardDebugScreen extends Screen {
 		return false;
 	}
 
-
+	public static int[] pinsA = new int[] { 2, 2, 2, 2, 2, 2, 2, 1, -1, -1, 0, 0, 0, 0, 2, -1 };
-	public static int[] pinsA = new int[]{2, 2, 2, 2, 2, 2, 2, 1, -1, -1, 0, 0, 0, 0, 2, -1};
+	public static int[] pinsB = new int[] { 0, 0, 2, 2, 2, 2, -1, 1, 0, -1, 2, 2, 2, 2, 0, -1 };
-	public static int[] pinsB = new int[]{0, 0, 2, 2, 2, 2, -1, 1, 0, -1, 2, 2, 2, 2, 0, -1};
 	public static boolean[] dataA = new boolean[8];
 	public static boolean[] dataB = new boolean[8];
 	public static boolean[][] ks = new boolean[8][8];
 	public static boolean[] gpio = new boolean[40];
 
 	public static void log(String str) {
-		String[] newlog = log;
+		final String[] newlog = log;
 		for (int i = 1; i < 5; i++) {
-			newlog[i-1] = newlog[i];
+			newlog[i - 1] = newlog[i];
 		}
 		newlog[4] = "[" + System.currentTimeMillis() + "]" + str;
 		log = newlog;

src/org/warp/picalculator/gui/screens/LoadingScreen.java

@@ -1,20 +1,20 @@
 package org.warp.picalculator.gui.screens;
 
-import static org.warp.picalculator.gui.PIDisplay.colore;
+import static org.warp.picalculator.gui.DisplayManager.colore;
-import static org.warp.picalculator.gui.PIDisplay.fonts;
+import static org.warp.picalculator.gui.DisplayManager.fonts;
 
 import org.warp.picalculator.Main;
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
+import org.warp.picalculator.gui.GraphicUtils;
 
 public class LoadingScreen extends Screen {
 
 	public float endLoading;
 	boolean mustRefresh = true;
 	public float loadingTextTranslation = 0.0f;
-	public boolean loadingTextTranslationTopToBottom = true;
 	private boolean loading;
-	private static final String titleString = "PICalculator by Andrea Cavalli";
+	private static final String titleString = "Andrea Cavalli's Algebraic Calculator";
 
 	public LoadingScreen() {
 		super();
@@ -27,52 +27,47 @@ public class LoadingScreen extends Screen {
 	}
 
 	@Override
-	public void init() throws InterruptedException {
+	public void init() throws InterruptedException {}
-	}
 
 	@Override
 	public void beforeRender(float dt) {
-		if (loadingTextTranslation >= 10.0f) {
+		loadingTextTranslation = GraphicUtils.sinDeg(endLoading * 90f) * 10f;
-			loadingTextTranslation = 10.0f;
-			loadingTextTranslationTopToBottom = false;
-		} else if (loadingTextTranslation <= -10.0f) {
-			loadingTextTranslation = -10.0f;
-			loadingTextTranslationTopToBottom = true;
-		}
-
-		if (loadingTextTranslationTopToBottom) {
-			loadingTextTranslation += dt * 15;
-		} else {
-			loadingTextTranslation -= dt * 15;
-		}
 
 		endLoading += dt;
-		if (endLoading >= 2) {
+		if (endLoading >= 5f) {
 			loading = false;
-			PIDisplay.INSTANCE.setScreen(new MathInputScreen());
+			DisplayManager.INSTANCE.setScreen(new MathInputScreen());
 		}
 		mustRefresh = true;
 	}
 
 	@Override
 	public void render() {
-		PIDisplay.renderer.glSetFont(fonts[2]);
+		fonts[2].use(DisplayManager.display);
-		colore(1.0f, 1.0f, 1.0f, 1.0f);
+		DisplayManager.renderer.glClearColor(0xFF000000);
-		PIDisplay.renderer.glDrawStringCenter((Main.screenSize[0] / 2) - 1,(int) ((Main.screenSize[1]/ 2) - 25 + loadingTextTranslation), titleString);
+		DisplayManager.renderer.glClear(DisplayManager.display.getWidth(), DisplayManager.display.getWidth());
-		colore(1.0f, 1.0f, 1.0f, 1.0f);
+		DisplayManager.renderer.glColor3i(230, 33, 23);
-		PIDisplay.renderer.glDrawStringCenter((Main.screenSize[0] / 2) + 1,(int) ((Main.screenSize[1]/ 2) - 25 + loadingTextTranslation), titleString);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) - 1, (int) ((Main.screenSize[1] / 2) - 25 + loadingTextTranslation), titleString);
-		colore(1.0f, 1.0f, 1.0f, 1.0f);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) - 2, (int) ((Main.screenSize[1] / 2) - 25 + loadingTextTranslation), titleString);
-		PIDisplay.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1]/ 2) - 25 - 1 + loadingTextTranslation), titleString);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) + 1, (int) ((Main.screenSize[1] / 2) - 25 + loadingTextTranslation), titleString);
-		colore(1.0f, 1.0f, 1.0f, 1.0f);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) + 2, (int) ((Main.screenSize[1] / 2) - 25 + loadingTextTranslation), titleString);
-		PIDisplay.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1]/ 2) - 25 + 1 + loadingTextTranslation), titleString);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1] / 2) - 25 - 1 + loadingTextTranslation), titleString);
-		colore(1.0f, 0.5f, 0.0f, 1.0f);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1] / 2) - 25 - 2 + loadingTextTranslation), titleString);
-		PIDisplay.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1]/ 2) - 25 + loadingTextTranslation), titleString);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1] / 2) - 25 + 1 + loadingTextTranslation), titleString);
-		colore(0.0f, 0.0f, 0.0f, 0.75f);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1] / 2) - 25 + 2 + loadingTextTranslation), titleString);
-		PIDisplay.renderer.glSetFont(fonts[0]);
+
-		PIDisplay.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (Main.screenSize[1]/ 2) + 11, "LOADING");
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) + 1, (int) ((Main.screenSize[1] / 2) - 25 + 1 + loadingTextTranslation), titleString);
-		PIDisplay.renderer.glSetFont(fonts[1]);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) - 1, (int) ((Main.screenSize[1] / 2) - 25 + 1 + loadingTextTranslation), titleString);
-		colore(0.0f, 0.0f, 0.0f, 0.5f);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) - 1, (int) ((Main.screenSize[1] / 2) - 25 - 1 + loadingTextTranslation), titleString);
-		PIDisplay.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (Main.screenSize[1]/ 2) + 22, "PLEASE WAIT...");
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2) + 1, (int) ((Main.screenSize[1] / 2) - 25 - 1 + loadingTextTranslation), titleString);
+		DisplayManager.renderer.glColor3i(255, 255, 255);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (int) ((Main.screenSize[1] / 2) - 25 + loadingTextTranslation), titleString);
+		DisplayManager.renderer.glColor4f(0.0f, 0.0f, 0.0f, 0.75f);
+		fonts[0].use(DisplayManager.display);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (Main.screenSize[1] / 2) + 11, "LOADING");
+		fonts[1].use(DisplayManager.display);
+		DisplayManager.renderer.glColor4f(0.0f, 0.0f, 0.0f, 0.5f);
+		DisplayManager.renderer.glDrawStringCenter((Main.screenSize[0] / 2), (Main.screenSize[1] / 2) + 22, "PLEASE WAIT...");
 
 	}
 

src/org/warp/picalculator/gui/screens/MarioScreen.java

@@ -8,17 +8,16 @@ import javax.imageio.ImageIO;
 import org.warp.picalculator.Main;
 import org.warp.picalculator.device.Keyboard;
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
+import org.warp.picalculator.gui.graphicengine.RAWSkin;
 
 public class MarioScreen extends Screen {
 
-	private int[] skin;
+	private RAWSkin skin;
-	private int[] skinSize;
+	private RAWSkin groundskin;
-	private int[] ground;
-	private int[] groundSize;
 	private boolean errored;
-	public float[] marioPos = new float[]{30,0};
+	public float[] marioPos = new float[] { 30, 0 };
-	public float[] marioForces = new float[]{0,0};
+	public float[] marioForces = new float[] { 0, 0 };
 	public float walkAnimation = 0;
 	public float jumptime = 0;
 	public boolean walking = false;
@@ -26,7 +25,7 @@ public class MarioScreen extends Screen {
 	public boolean jumping = false;
 	public boolean flipped = false;
 	public boolean onGround = true;
-	public int[] marioSkinPos = new int[]{0,0};
+	public int[] marioSkinPos = new int[] { 0, 0 };
 
 	public MarioScreen() {
 		super();
@@ -35,22 +34,11 @@ public class MarioScreen extends Screen {
 
 	@Override
 	public void init() {
-		BufferedImage img;
 		try {
-			img = ImageIO.read(Main.instance.getClass().getResource("/marioskin.png"));
+			skin = DisplayManager.display.loadSkin("marioskin.png");
-			skin = PIDisplay.renderer.getMatrixOfImage(img);
+			groundskin = DisplayManager.display.loadSkin("marioground.png");
-			skinSize = new int[] { img.getWidth(), img.getHeight() };
 		} catch (IOException e) {
 			e.printStackTrace();
-			errored = true;
-		}
-		try {
-			img = ImageIO.read(Main.instance.getClass().getResource("/marioground.png"));
-			ground = PIDisplay.renderer.getMatrixOfImage(img);
-			groundSize = new int[] { img.getWidth(), img.getHeight() };
-		} catch (IOException e) {
-			e.printStackTrace();
-			errored = true;
 		}
 	}
 
@@ -65,36 +53,36 @@ public class MarioScreen extends Screen {
 	public void beforeRender(float dt) {
 		if (!errored) {
 			walkAnimation += dt;
-			boolean rightPressed = Keyboard.isKeyDown(2, 5);
+			final boolean rightPressed = Keyboard.isKeyDown(2, 5);
-			boolean leftPressed = Keyboard.isKeyDown(2, 3);
+			final boolean leftPressed = Keyboard.isKeyDown(2, 3);
-			boolean jumpPressed = Keyboard.isKeyDown(2, 1);
+			final boolean jumpPressed = Keyboard.isKeyDown(2, 1);
 			if ((leftPressed || rightPressed) == (leftPressed & rightPressed)) {
 				walking = false;
 				walkAnimation = 0;
 			} else {
 				if (rightPressed) { //RIGHT
 					if (marioForces[0] < 500f) {
-						marioForces[0] += dt*500f;
+						marioForces[0] += dt * 500f;
 					}
 					walking = true;
 					flipped = false;
 				}
 				if (leftPressed) { //LEFT
 					if (marioForces[0] > -500f) {
-						marioForces[0] -= dt*500f;
+						marioForces[0] -= dt * 500f;
 					}
 					walking = true;
 					flipped = true;
 				}
 			}
 			if (jumpPressed) { //JUMP
-				jumptime+=dt;
+				jumptime += dt;
 				if (!jumping && onGround) {
-					marioForces[1] = dt*(4*1569.6f);
+					marioForces[1] = dt * (4 * 1569.6f);
 					jumping = true;
 					onGround = false;
 				} else if (jumptime <= 0.5f) {
-					marioForces[1] = dt*(4*1569.6f);
+					marioForces[1] = dt * (4 * 1569.6f);
 				}
 			} else {
 				jumping = false;
@@ -104,7 +92,7 @@ public class MarioScreen extends Screen {
 				marioSkinPos[0] = 0;
 				marioSkinPos[1] = 0;
 			} else if (onGround & walking & !running & !jumping && walkAnimation >= 0.08) {
-				while(walkAnimation > 0.08) {
+				while (walkAnimation > 0.08) {
 					walkAnimation -= 0.08;
 					if (marioSkinPos[0] == 1 & marioSkinPos[1] == 0) {
 						marioSkinPos[0] += 2;
@@ -121,41 +109,43 @@ public class MarioScreen extends Screen {
 				marioSkinPos[0] = 5;
 				marioSkinPos[1] = 1;
 			}
-			marioForces[1] -= dt*1569.6;
+			marioForces[1] -= dt * 1569.6;
-			marioPos[0] += dt*marioForces[0];
+			marioPos[0] += dt * marioForces[0];
 			if (!onGround) {
-				marioPos[1] -= dt*marioForces[1];
+				marioPos[1] -= dt * marioForces[1];
 			}
 			marioForces[0] *= 0.75;
 
-			PIDisplay.renderer.glClearColor(0xff9290ff);
+			DisplayManager.renderer.glClearColor(0xff9290ff);
 		}
 	}
 
 	@Override
 	public void render() {
 		if (errored) {
-			PIDisplay.renderer.glDrawStringLeft(0, 20, "ERROR");
+			DisplayManager.renderer.glDrawStringLeft(0, 20, "ERROR");
 		} else {
-			PIDisplay.renderer.glSetFont(PIDisplay.fonts[0]);
+			DisplayManager.fonts[0].use(DisplayManager.display);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 0, 25+25, 0, 0, 16, 16, false);
+			groundskin.use(DisplayManager.display);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 0, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*2, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 1, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*3, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 2, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*4, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 3, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*5, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 4, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*6, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 5, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*7, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 6, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*8, 25+25, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 7, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 0, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 8, 25 + 25, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16, 25+25+16, 0, 0, 16, 16, false);
+
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*2, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 0, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*3, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 1, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*4, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 2, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*5, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 3, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*6, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 4, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*7, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 5, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
-			PIDisplay.renderer.glDrawSkin(groundSize[0], ground, 16*8, 25+25+16, 0, 0, 16, 16, false);
+			DisplayManager.renderer.glFillRect(16 * 6, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
+			DisplayManager.renderer.glFillRect(16 * 7, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
+			DisplayManager.renderer.glFillRect(16 * 8, 25 + 25 + 16 * 1, 16, 16, 0, 0, 16, 16);
 
 //		EASTER EGG
 //			glSetFont(PIDisplay.fonts[4]);
@@ -175,7 +165,9 @@ public class MarioScreen extends Screen {
 //			glDrawStringRight(0, Main.screenSize[1]-glGetCurrentFontHeight(), "G");
 
 			//DRAW MARIO
-			PIDisplay.renderer.glDrawSkin(skinSize[0], skin, getPosX()-18, 25+getPosY(), 35*(marioSkinPos[0]+(flipped?2:1)), 27*marioSkinPos[1], 35*(marioSkinPos[0]+(flipped?1:2)), 27*(marioSkinPos[1]+1), true);
+			skin.use(DisplayManager.display);
+			DisplayManager.renderer.glFillRect(getPosX() - 18, 25 + getPosY(), 35, 27, 35 * (marioSkinPos[0] + 1), 27 * marioSkinPos[1], 35, 27);
+//			PIDisplay.renderer.glDrawSkin(getPosX() - 18, 25 + getPosY(), 35 * (marioSkinPos[0] + (flipped ? 2 : 1)), 27 * marioSkinPos[1], 35 * (marioSkinPos[0] + (flipped ? 1 : 2)), 27 * (marioSkinPos[1] + 1), true);
 		}
 	}
 
@@ -195,11 +187,11 @@ public class MarioScreen extends Screen {
 	}
 
 	private int getPosX() {
-		return (int)marioPos[0];
+		return (int) marioPos[0];
 	}
 
 	private int getPosY() {
-		return (int)marioPos[1];
+		return (int) marioPos[1];
 	}
 
 }

src/org/warp/picalculator/gui/screens/MathInputScreen.java

@@ -15,8 +15,9 @@ import org.warp.picalculator.Main;
 import org.warp.picalculator.Utils;
 import org.warp.picalculator.device.Keyboard;
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.RAWFont;
+import org.warp.picalculator.gui.graphicengine.Renderer;
 import org.warp.picalculator.math.AngleMode;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.MathematicalSymbols;
@@ -114,7 +115,7 @@ public class MathInputScreen extends Screen {
 	}
 
 	public void interpreta(boolean temporary) throws Error {
-		String eqn = nuovaEquazione;
+		final String eqn = nuovaEquazione;
 		if (!temporary) {
 			equazioneCorrente = eqn;
 		}
@@ -134,10 +135,10 @@ public class MathInputScreen extends Screen {
 			caretPos = nuovaEquazione.length();
 		}
 
-		if (PIDisplay.error == null) {
+		if (DisplayManager.error == null) {
-			PIDisplay.renderer.glClearColor(0xFFc5c2af);
+			DisplayManager.renderer.glClearColor(0xFFc5c2af);
 		} else {
-			PIDisplay.renderer.glClearColor(0xFFDC3C32);
+			DisplayManager.renderer.glClearColor(0xFFDC3C32);
 		}
 	}
 
@@ -145,28 +146,28 @@ public class MathInputScreen extends Screen {
 
 	@Override
 	public void renderStatusbar() {
-		PIDisplay.renderer.glColor3i(0, 0, 0);
+		Renderer renderer = DisplayManager.renderer;
-		int pos = 2;
+		renderer.glColor3f(1, 1, 1);
-		int spacersNumb = 1;
+		final int pos = 2;
+		final int spacersNumb = 1;
 		int skinN = 0;
 		if (calc.exactMode) {
 			skinN = 22;
-			PIDisplay.drawSkinPart(2 + 18 * pos + 2 * spacersNumb, 2, 16 * skinN, 16 * 0, 16 + 16 * skinN, 16 + 16 * 0);
 		} else {
 			skinN = 21;
-			PIDisplay.drawSkinPart(2 + 18 * pos + 2 * spacersNumb, 2, 16 * skinN, 16 * 0, 16 + 16 * skinN, 16 + 16 * 0);
 		}
+		renderer.glFillRect(2 + 18 * pos + 2 * spacersNumb, 2, 16, 16, 16 * skinN, 16 * 0, 16, 16);
 	}
 
 	@Override
 	public void render() {
-		PIDisplay.renderer.glSetFont(fontBig);
+		fontBig.use(DisplayManager.display);
 		final int textColor = 0xFF000000;
 		final int padding = 4;
-		PIDisplay.renderer.glColor(textColor);
+		DisplayManager.renderer.glColor(textColor);
-		final int caretRealPos = MathematicalSymbols.getGraphicRepresentation(nuovaEquazione.substring(0, caretPos)).length()*(fontBig.charW+1);
+		final int caretRealPos = MathematicalSymbols.getGraphicRepresentation(nuovaEquazione.substring(0, caretPos)).length() * (fontBig.getCharacterWidth() + 1);
 		final String inputTextWithoutCaret = MathematicalSymbols.getGraphicRepresentation(nuovaEquazione);
-		final boolean tooLongI = padding+PIDisplay.renderer.glGetStringWidth(fontBig, nuovaEquazione)+padding >= Main.screenSize[0];
+		final boolean tooLongI = padding + fontBig.getStringWidth(nuovaEquazione) + padding >= Main.screenSize[0];
 		int scrollI = 0;
 		if (tooLongI) {
 			scrollI = -scrollX;
@@ -176,23 +177,23 @@ public class MathInputScreen extends Screen {
 				scrollI = 0;
 			}
 		}
-		PIDisplay.renderer.glDrawStringLeft(padding+scrollI, padding+20, inputTextWithoutCaret);
+		DisplayManager.renderer.glDrawStringLeft(padding + scrollI, padding + 20, inputTextWithoutCaret);
 		if (showCaret) {
-			PIDisplay.renderer.glDrawStringLeft(padding+scrollI+caretRealPos, padding+20, "|");
+			DisplayManager.renderer.glDrawStringLeft(padding + scrollI + caretRealPos, padding + 20, "|");
 		}
 		if (tooLongI) {
-			PIDisplay.renderer.glColor(PIDisplay.renderer.glGetClearColor());
+			DisplayManager.renderer.glColor(DisplayManager.renderer.glGetClearColor());
-			PIDisplay.renderer.glFillRect(Main.screenSize[0]-16-2, padding+20, fontBig.charH, Main.screenSize[0]);
+			DisplayManager.renderer.glFillColor(Main.screenSize[0] - 16 - 2, padding + 20, fontBig.getCharacterHeight(), Main.screenSize[0]);
-			PIDisplay.renderer.glColor(textColor);
+			DisplayManager.renderer.glColor(textColor);
-			PIDisplay.drawSkinPart(Main.screenSize[0]-16, padding+20+fontBig.charH/2-16/2, 304, 0, 304+16, 16);
+			DisplayManager.drawSkinPart(Main.screenSize[0] - 16, padding + 20 + fontBig.getCharacterHeight() / 2 - 16 / 2, 304, 0, 304 + 16, 16);
 		}
 		if (calc.f != null) {
 			int topSpacing = 0;
-			Iterator<Function> iter = calc.f.iterator();
+			final Iterator<Function> iter = calc.f.iterator();
 			while (iter.hasNext()) {
-				Function fnc = iter.next();
+				final Function fnc = iter.next();
 				try {
-					final boolean tooLong = padding+fnc.getWidth()+padding >= Main.screenSize[0];
+					final boolean tooLong = padding + fnc.getWidth() + padding >= Main.screenSize[0];
 					int scrollA = 0;
 					if (tooLong) {
 						scrollA = -scrollX;
@@ -202,15 +203,15 @@ public class MathInputScreen extends Screen {
 							scrollA = 0;
 						}
 					}
-					final int y = padding+20+padding+fontBig.charH+1+topSpacing;
+					final int y = padding + 20 + padding + fontBig.getCharacterHeight() + 1 + topSpacing;
-					fnc.draw(padding+scrollA, y);
+					fnc.draw(padding + scrollA, y);
 					if (tooLong) {
-						PIDisplay.renderer.glColor(PIDisplay.renderer.glGetClearColor());
+						DisplayManager.renderer.glColor(DisplayManager.renderer.glGetClearColor());
-						PIDisplay.renderer.glFillRect(Main.screenSize[0]-16-2, y, fnc.getHeight(), Main.screenSize[0]);
+						DisplayManager.renderer.glFillColor(Main.screenSize[0] - 16 - 2, y, fnc.getHeight(), Main.screenSize[0]);
-						PIDisplay.renderer.glColor(textColor);
+						DisplayManager.renderer.glColor(textColor);
-						PIDisplay.drawSkinPart(Main.screenSize[0]-16, y+fnc.getHeight()/2-16/2, 304, 0, 304+16, 16);
+						DisplayManager.drawSkinPart(Main.screenSize[0] - 16, y + fnc.getHeight() / 2 - 16 / 2, 304, 0, 304 + 16, 16);
 					}
-				} catch (NullPointerException e) {
+				} catch (final NullPointerException e) {
 					iter.remove();
 				}
 				topSpacing += fnc.getHeight() + 2;
@@ -218,16 +219,16 @@ public class MathInputScreen extends Screen {
 		}
 		if (calc.f2 != null) {
 			int bottomSpacing = 0;
-			for (Function f : calc.f2) {
+			for (final Function f : calc.f2) {
-				bottomSpacing += f.getHeight()+2;
+				bottomSpacing += f.getHeight() + 2;
-				f.draw(PIDisplay.display.getWidth() - 2 - f.getWidth(), PIDisplay.display.getHeight() - bottomSpacing);
+				f.draw(DisplayManager.display.getWidth() - 2 - f.getWidth(), DisplayManager.display.getHeight() - bottomSpacing);
 			}
 			if (calc.resultsCount > 1 && calc.resultsCount != calc.f2.size()) {
-				String resultsCountText = calc.resultsCount+" total results".toUpperCase();
+				final String resultsCountText = calc.resultsCount + " total results".toUpperCase();
-				PIDisplay.renderer.glColor(0xFF9AAEA0);
+				DisplayManager.renderer.glColor(0xFF9AAEA0);
-				PIDisplay.renderer.glSetFont(Utils.getFont(true));
+				Utils.getFont(true).use(DisplayManager.display);
-				bottomSpacing += fontBig.charH+2;
+				bottomSpacing += fontBig.getCharacterHeight() + 2;
-				PIDisplay.renderer.glDrawStringRight(PIDisplay.display.getWidth() - 2, PIDisplay.display.getHeight() - bottomSpacing, resultsCountText);
+				DisplayManager.renderer.glDrawStringRight(DisplayManager.display.getWidth() - 2, DisplayManager.display.getHeight() - bottomSpacing, resultsCountText);
 			}
 		}
 	}
@@ -251,26 +252,24 @@ public class MathInputScreen extends Screen {
 						try {
 							try {
 								interpreta(true);
-								showVariablesDialog(new Runnable(){
+								showVariablesDialog(() -> {
-									@Override
+									equazioneCorrente = nuovaEquazione;
-									public void run() {
+									calc.f2 = calc.f;
-										equazioneCorrente = nuovaEquazione;
+									afterDoNextStep = true;
-										calc.f2 = calc.f;
+									simplify(MathInputScreen.this);
-										afterDoNextStep = true;
-										simplify(MathInputScreen.this);
-									}
 								});
-							} catch (Exception ex) {
+							} catch (final Exception ex) {
-								if (Utils.debugOn)
+								if (Utils.debugOn) {
 									ex.printStackTrace();
+								}
 								throw new Error(Errors.SYNTAX_ERROR);
 							}
-						} catch (Error e) {
+						} catch (final Error e) {
-							StringWriter sw = new StringWriter();
+							final StringWriter sw = new StringWriter();
-							PrintWriter pw = new PrintWriter(sw);
+							final PrintWriter pw = new PrintWriter(sw);
 							e.printStackTrace(pw);
 							d.errorStackTrace = sw.toString().toUpperCase().replace("\t", "    ").replace("\r", "").split("\n");
-							PIDisplay.error = e.id.toString();
+							DisplayManager.error = e.id.toString();
 							System.err.println(e.id);
 						}
 					} else {
@@ -279,10 +278,10 @@ public class MathInputScreen extends Screen {
 				}
 				return true;
 			case SOLVE:
-				if (PIDisplay.error != null) {
+				if (DisplayManager.error != null) {
 					Utils.debug.println("Resetting after error...");
-					PIDisplay.error = null;
+					DisplayManager.error = null;
-					this.equazioneCorrente = null;
+					equazioneCorrente = null;
 					calc.f = null;
 					calc.f2 = null;
 					calc.resultsCount = 0;
@@ -296,26 +295,24 @@ public class MathInputScreen extends Screen {
 								if (nuovaEquazione != equazioneCorrente && nuovaEquazione.length() > 0) {
 									changeEquationScreen();
 									interpreta(true);
-									showVariablesDialog(new Runnable(){
+									showVariablesDialog(() -> {
-										@Override
+										equazioneCorrente = nuovaEquazione;
-										public void run() {
+										solve();
-											equazioneCorrente = nuovaEquazione;
+									});
-											solve();
-										}});
 								}
 							}
-						} catch (Exception ex) {
+						} catch (final Exception ex) {
 							if (Utils.debugOn) {
 								ex.printStackTrace();
 							}
 							throw new Error(Errors.SYNTAX_ERROR);
 						}
-					} catch (Error e) {
+					} catch (final Error e) {
-						StringWriter sw = new StringWriter();
+						final StringWriter sw = new StringWriter();
-						PrintWriter pw = new PrintWriter(sw);
+						final PrintWriter pw = new PrintWriter(sw);
 						e.printStackTrace(pw);
 						d.errorStackTrace = sw.toString().toUpperCase().replace("\t", "    ").replace("\r", "").split("\n");
-						PIDisplay.error = e.id.toString();
+						DisplayManager.error = e.id.toString();
 						System.err.println(e.id);
 					}
 					return true;
@@ -384,7 +381,7 @@ public class MathInputScreen extends Screen {
 				typeChar("√");
 				return true;
 			case POWER_OF_2:
-				typeChar(MathematicalSymbols.POWER+"2");
+				typeChar(MathematicalSymbols.POWER + "2");
 				return true;
 			case POWER_OF_x:
 				typeChar(MathematicalSymbols.POWER);
@@ -419,12 +416,14 @@ public class MathInputScreen extends Screen {
 			case DELETE:
 				if (nuovaEquazione.length() > 0) {
 					if (caretPos > 0) {
-						caretPos-=1;
+						caretPos -= 1;
-						nuovaEquazione=nuovaEquazione.substring(0, caretPos)+nuovaEquazione.substring(caretPos+1, nuovaEquazione.length());
+						nuovaEquazione = nuovaEquazione.substring(0, caretPos) + nuovaEquazione.substring(caretPos + 1, nuovaEquazione.length());
 					} else {
 						nuovaEquazione = nuovaEquazione.substring(1);
 					}
-					try {interpreta(true);} catch (Error e) {}
+					try {
+						interpreta(true);
+					} catch (final Error e) {}
 				}
 				afterDoNextStep = false;
 				return true;
@@ -434,7 +433,7 @@ public class MathInputScreen extends Screen {
 				} else {
 					caretPos = nuovaEquazione.length();
 				}
-				scrollX = PIDisplay.renderer.glGetStringWidth(fontBig, nuovaEquazione.substring(0, caretPos)+"|||");
+				scrollX = fontBig.getStringWidth(nuovaEquazione.substring(0, caretPos) + "|||");
 				showCaret = true;
 				showCaretDelta = 0L;
 				return true;
@@ -444,18 +443,18 @@ public class MathInputScreen extends Screen {
 				} else {
 					caretPos = 0;
 				}
-				scrollX = PIDisplay.renderer.glGetStringWidth(fontBig, nuovaEquazione.substring(0, caretPos)+"|||");
+				scrollX = fontBig.getStringWidth(nuovaEquazione.substring(0, caretPos) + "|||");
 				showCaret = true;
 				showCaretDelta = 0L;
 				return true;
 			case RESET:
-				if (PIDisplay.error != null) {
+				if (DisplayManager.error != null) {
 					Utils.debug.println("Resetting after error...");
-					PIDisplay.error = null;
+					DisplayManager.error = null;
 					return true;
 				} else {
 					caretPos = 0;
-					nuovaEquazione="";
+					nuovaEquazione = "";
 					afterDoNextStep = false;
 					if (calc.f != null) {
 						calc.f.clear();
@@ -472,27 +471,25 @@ public class MathInputScreen extends Screen {
 				}
 				return true;
 			case debug1:
-				PIDisplay.INSTANCE.setScreen(new EmptyScreen());
+				DisplayManager.INSTANCE.setScreen(new EmptyScreen());
 				return true;
 			case HISTORY_BACK:
-				if (PIDisplay.INSTANCE.canGoBack()) {
+				if (DisplayManager.INSTANCE.canGoBack()) {
-					if (equazioneCorrente != null && equazioneCorrente.length() > 0 & PIDisplay.sessions[PIDisplay.currentSession+1] instanceof MathInputScreen) {
+					if (equazioneCorrente != null && equazioneCorrente.length() > 0 & DisplayManager.sessions[DisplayManager.currentSession + 1] instanceof MathInputScreen) {
 						nuovaEquazione = equazioneCorrente;
 						try {
 							interpreta(true);
-						} catch (Error e) {
+						} catch (final Error e) {}
-						}
 					}
 				}
 				return false;
 			case HISTORY_FORWARD:
-				if (PIDisplay.INSTANCE.canGoForward()) {
+				if (DisplayManager.INSTANCE.canGoForward()) {
-					if (equazioneCorrente != null && equazioneCorrente.length() > 0 & PIDisplay.sessions[PIDisplay.currentSession-1] instanceof MathInputScreen) {
+					if (equazioneCorrente != null && equazioneCorrente.length() > 0 & DisplayManager.sessions[DisplayManager.currentSession - 1] instanceof MathInputScreen) {
 						nuovaEquazione = equazioneCorrente;
 						try {
 							interpreta(true);
-						} catch (Error e) {
+						} catch (final Error e) {}
-						}
 					}
 				}
 				return false;
@@ -532,18 +529,18 @@ public class MathInputScreen extends Screen {
 		try {
 			try {
 				return calc.solveExpression(f22);
-			} catch (Exception ex) {
+			} catch (final Exception ex) {
 				if (Utils.debugOn) {
 					ex.printStackTrace();
 				}
 				throw new Error(Errors.SYNTAX_ERROR);
 			}
-		} catch (Error e) {
+		} catch (final Error e) {
-			StringWriter sw = new StringWriter();
+			final StringWriter sw = new StringWriter();
-			PrintWriter pw = new PrintWriter(sw);
+			final PrintWriter pw = new PrintWriter(sw);
 			e.printStackTrace(pw);
 			d.errorStackTrace = sw.toString().toUpperCase().replace("\t", "    ").replace("\r", "").split("\n");
-			PIDisplay.error = e.id.toString();
+			DisplayManager.error = e.id.toString();
 			System.err.println(e.id);
 		}
 		return null;
@@ -554,15 +551,15 @@ public class MathInputScreen extends Screen {
 			try {
 				showVariablesDialog();
 				ArrayList<Function> results = new ArrayList<>();
-				ArrayList<Function> partialResults = new ArrayList<>();
+				final ArrayList<Function> partialResults = new ArrayList<>();
-				for (Function f : calc.f2) {
+				for (final Function f : calc.f2) {
 					if (f instanceof Equation) {
-						PIDisplay.INSTANCE.setScreen(new SolveEquationScreen(this));
+						DisplayManager.INSTANCE.setScreen(new SolveEquationScreen(this));
 					} else {
 						results.add(f);
-						for (Function itm : results) {
+						for (final Function itm : results) {
 							if (itm.isSolved() == false) {
-								List<Function> dt = itm.solveOneStep();
+								final List<Function> dt = itm.solveOneStep();
 								partialResults.addAll(dt);
 							} else {
 								partialResults.add(itm);
@@ -579,27 +576,27 @@ public class MathInputScreen extends Screen {
 					calc.resultsCount = results.size();
 					Collections.reverse(results);
 					// add elements to al, including duplicates
-					Set<Function> hs = new LinkedHashSet<>();
+					final Set<Function> hs = new LinkedHashSet<>();
 					hs.addAll(results);
 					results.clear();
 					results.addAll(hs);
 					calc.f2 = results;
-					for (Function rf : calc.f2) {
+					for (final Function rf : calc.f2) {
 						rf.generateGraphics();
 					}
 				}
-			} catch (Exception ex) {
+			} catch (final Exception ex) {
 				if (Utils.debugOn) {
 					ex.printStackTrace();
 				}
 				throw new Error(Errors.SYNTAX_ERROR);
 			}
-		} catch (Error e) {
+		} catch (final Error e) {
-			StringWriter sw = new StringWriter();
+			final StringWriter sw = new StringWriter();
-			PrintWriter pw = new PrintWriter(sw);
+			final PrintWriter pw = new PrintWriter(sw);
 			e.printStackTrace(pw);
 			d.errorStackTrace = sw.toString().toUpperCase().replace("\t", "    ").replace("\r", "").split("\n");
-			PIDisplay.error = e.id.toString();
+			DisplayManager.error = e.id.toString();
 			System.err.println(e.id);
 		}
 	}
@@ -607,71 +604,72 @@ public class MathInputScreen extends Screen {
 	protected void solve() {
 		try {
 			try {
-				for (Function f : calc.f) {
+				for (final Function f : calc.f) {
 					if (f instanceof Equation) {
-						PIDisplay.INSTANCE.setScreen(new SolveEquationScreen(this));
+						DisplayManager.INSTANCE.setScreen(new SolveEquationScreen(this));
 						return;
 					}
 				}
 
-				ArrayList<Function> results = solveExpression(calc.f);
+				final ArrayList<Function> results = solveExpression(calc.f);
 				if (results.size() == 0) {
 					calc.resultsCount = 0;
 				} else {
 					calc.resultsCount = results.size();
 					Collections.reverse(results);
 					// add elements to al, including duplicates
-					Set<Function> hs = new LinkedHashSet<>();
+					final Set<Function> hs = new LinkedHashSet<>();
 					hs.addAll(results);
 					results.clear();
 					results.addAll(hs);
 					calc.f2 = results;
-					for (Function rf : calc.f2) {
+					for (final Function rf : calc.f2) {
 						rf.generateGraphics();
 					}
 				}
-			} catch (Exception ex) {
+			} catch (final Exception ex) {
 				if (Utils.debugOn) {
 					ex.printStackTrace();
 				}
 				throw new Error(Errors.SYNTAX_ERROR);
 			}
-		} catch (Error e) {
+		} catch (final Error e) {
-			StringWriter sw = new StringWriter();
+			final StringWriter sw = new StringWriter();
-			PrintWriter pw = new PrintWriter(sw);
+			final PrintWriter pw = new PrintWriter(sw);
 			e.printStackTrace(pw);
 			d.errorStackTrace = sw.toString().toUpperCase().replace("\t", "    ").replace("\r", "").split("\n");
-			PIDisplay.error = e.id.toString();
+			DisplayManager.error = e.id.toString();
 			System.err.println(e.id);
 		}
 	}
 
 	private void changeEquationScreen() {
 		if (equazioneCorrente != null && equazioneCorrente.length() > 0) {
-			MathInputScreen cloned = clone();
+			final MathInputScreen cloned = clone();
 			cloned.caretPos = cloned.equazioneCorrente.length();
 			cloned.nuovaEquazione = cloned.equazioneCorrente;
-			cloned.scrollX = PIDisplay.renderer.glGetStringWidth(fontBig, cloned.equazioneCorrente);
+			cloned.scrollX = fontBig.getStringWidth(cloned.equazioneCorrente);
-			try {cloned.interpreta(true);} catch (Error e) {}
+			try {
-			PIDisplay.INSTANCE.replaceScreen(cloned);
+				cloned.interpreta(true);
-			this.initialized = false;
+			} catch (final Error e) {}
-			PIDisplay.INSTANCE.setScreen(this);
+			DisplayManager.INSTANCE.replaceScreen(cloned);
+			initialized = false;
+			DisplayManager.INSTANCE.setScreen(this);
 
 		}
 	}
 
 	public void typeChar(String chr) {
-		int len = chr.length();
+		final int len = chr.length();
-		nuovaEquazione=nuovaEquazione.substring(0, caretPos)+chr+nuovaEquazione.substring(caretPos, nuovaEquazione.length());
+		nuovaEquazione = nuovaEquazione.substring(0, caretPos) + chr + nuovaEquazione.substring(caretPos, nuovaEquazione.length());
-		caretPos+=len;
+		caretPos += len;
-		scrollX = PIDisplay.renderer.glGetStringWidth(fontBig, nuovaEquazione.substring(0, caretPos)+"|||");
+		scrollX = fontBig.getStringWidth(nuovaEquazione.substring(0, caretPos) + "|||");
 		showCaret = true;
 		showCaretDelta = 0L;
 		afterDoNextStep = false;
 		try {
 			interpreta(true);
-		} catch (Error e) {
+		} catch (final Error e) {}
-		}
 //		f.clear(); //TODO: I removed this line to prevent input blanking when pressing EQUALS button and cloning this screen, but I must see why I created this part of code.
 	}
 
@@ -685,24 +683,24 @@ public class MathInputScreen extends Screen {
 	}
 
 	public void showVariablesDialog(final Runnable runnable) {
-		Thread ct = new Thread(()->{
+		final Thread ct = new Thread(() -> {
-			ArrayList<Function> variablesInFunctions = getVariables(calc.f.toArray(new Function[calc.f.size()]));
+			final ArrayList<Function> variablesInFunctions = getVariables(calc.f.toArray(new Function[calc.f.size()]));
-			for (VariableValue f : calc.variablesValues) {
+			for (final VariableValue f : calc.variablesValues) {
 				if (variablesInFunctions.contains(f.v)) {
 					variablesInFunctions.remove(f.v);
 				}
 			}
 
 			boolean cancelled = false;
-			for (Function f : variablesInFunctions) {
+			for (final Function f : variablesInFunctions) {
-				ChooseVariableValueScreen cvs = new ChooseVariableValueScreen(this, new VariableValue((Variable) f, new Number(calc, 0)));
+				final ChooseVariableValueScreen cvs = new ChooseVariableValueScreen(this, new VariableValue((Variable) f, new Number(calc, 0)));
-				PIDisplay.INSTANCE.setScreen(cvs);
+				DisplayManager.INSTANCE.setScreen(cvs);
 				try {
-					while (PIDisplay.screen == cvs) {
+					while (DisplayManager.screen == cvs) {
 						Utils.debug.println(Thread.currentThread().getName());
 						Thread.sleep(200);
 					}
-				} catch (InterruptedException e) {}
+				} catch (final InterruptedException e) {}
 				if (cvs.resultNumberValue == null) {
 					cancelled = true;
 					break;
@@ -716,7 +714,7 @@ public class MathInputScreen extends Screen {
 					calc.variablesValues.add(new VariableValue((Variable) f, (Number) cvs.resultNumberValue));
 				}
 			}
-			if (!cancelled)  {
+			if (!cancelled) {
 				if (runnable != null) {
 					runnable.run();
 				}
@@ -730,14 +728,14 @@ public class MathInputScreen extends Screen {
 	}
 
 	private ArrayList<Function> getVariables(Function[] fncs) {
-		ArrayList<Function> res = new ArrayList<>();
+		final ArrayList<Function> res = new ArrayList<>();
-		for (Function f : fncs) {
+		for (final Function f : fncs) {
 			if (f instanceof FunctionTwoValues) {
-				res.addAll(getVariables(new Function[]{((FunctionTwoValues)f).getVariable1(), ((FunctionTwoValues)f).getVariable2()}));
+				res.addAll(getVariables(new Function[] { ((FunctionTwoValues) f).getVariable1(), ((FunctionTwoValues) f).getVariable2() }));
 			} else if (f instanceof FunctionMultipleValues) {
-				res.addAll(getVariables(((FunctionMultipleValues)f).getVariables()));
+				res.addAll(getVariables(((FunctionMultipleValues) f).getVariables()));
 			} else if (f instanceof AnteriorFunction) {
-				res.addAll(getVariables(new Function[]{((AnteriorFunction)f).getVariable()}));
+				res.addAll(getVariables(new Function[] { ((AnteriorFunction) f).getVariable() }));
 			} else if (f instanceof Variable) {
 				if (!res.contains(f)) {
 					res.add(f);
@@ -749,8 +747,8 @@ public class MathInputScreen extends Screen {
 
 	@Override
 	public MathInputScreen clone() {
-		MathInputScreen es = this;
+		final MathInputScreen es = this;
-		MathInputScreen es2 = new MathInputScreen();
+		final MathInputScreen es2 = new MathInputScreen();
 		es2.scrollX = es.scrollX;
 		es2.nuovaEquazione = es.nuovaEquazione;
 		es2.equazioneCorrente = es.equazioneCorrente;

src/org/warp/picalculator/gui/screens/Screen.java

@@ -1,10 +1,10 @@
 package org.warp.picalculator.gui.screens;
 
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 
 public abstract class Screen {
-	public PIDisplay d;
+	public DisplayManager d;
 	public boolean created = false;
 	public boolean initialized = false;
 	public boolean canBeInHistory = false;

src/org/warp/picalculator/gui/screens/SolveEquationScreen.java

@@ -3,13 +3,13 @@ package org.warp.picalculator.gui.screens;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Main;
 import org.warp.picalculator.device.Keyboard.Key;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.Calculator;
 
 public class SolveEquationScreen extends Screen {
 
 	@SuppressWarnings("unused")
-	private MathInputScreen es;
+	private final MathInputScreen es;
 
 	public SolveEquationScreen(MathInputScreen es) {
 		super();
@@ -19,20 +19,19 @@ public class SolveEquationScreen extends Screen {
 	}
 
 	@Override
-	public void created() throws InterruptedException {
+	public void created() throws InterruptedException {}
-	}
 
 	@Override
 	public void init() throws InterruptedException {}
 
 	@Override
 	public void render() {
-		PIDisplay.renderer.glColor4i(0, 0, 0, 64);
+		DisplayManager.renderer.glColor4i(0, 0, 0, 64);
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2+1, Main.screenSize[1]/4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2 + 1, Main.screenSize[1] / 4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2, Main.screenSize[1]/4+1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2, Main.screenSize[1] / 4 + 1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2+1, Main.screenSize[1]/4+1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2 + 1, Main.screenSize[1] / 4 + 1, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
-		PIDisplay.renderer.glColor3i(255, 0, 0);
+		DisplayManager.renderer.glColor3i(255, 0, 0);
-		PIDisplay.renderer.glDrawStringCenter(Main.screenSize[0]/2, Main.screenSize[1]/4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
+		DisplayManager.renderer.glDrawStringCenter(Main.screenSize[0] / 2, Main.screenSize[1] / 4, "WORK IN PROGRESS. THIS SCREEN MUST HAVE A GUI TO SELECT THE VARIABLE TO SOLVE.");
 	}
 
 	@Override
@@ -49,13 +48,13 @@ public class SolveEquationScreen extends Screen {
 	public boolean keyPressed(Key k) {
 		switch (k) {
 			case LETTER_X:
-				PIDisplay.INSTANCE.goBack();
+				DisplayManager.INSTANCE.goBack();
 				try {
 					es.calc.solveExpression('X');
-				} catch (Error e) {
+				} catch (final Error e) {
-					Screen scr = PIDisplay.INSTANCE.getScreen();
+					final Screen scr = DisplayManager.INSTANCE.getScreen();
 					if (scr instanceof MathInputScreen) {
-						MathInputScreen escr = (MathInputScreen) scr;
+						final MathInputScreen escr = (MathInputScreen) scr;
 						escr.errorLevel = 1;
 						//escr.err2 = e; //TODO: What is this variable, and why it doesn't exists?
 					} else {

src/org/warp/picalculator/math/AngleMode.java

@@ -1,7 +1,5 @@
 package org.warp.picalculator.math;
 
 public enum AngleMode {
-	DEG,
+	DEG, RAD, GRA
-	RAD,
-	GRA
 }

src/org/warp/picalculator/math/Calculator.java

@@ -34,9 +34,9 @@ public class Calculator {
 			if (!string.startsWith("{")) {
 				throw new Error(Errors.SYNTAX_ERROR);
 			}
-			String[] parts = string.substring(1).split("\\{");
+			final String[] parts = string.substring(1).split("\\{");
-			EquationsSystem s = new EquationsSystem(this);
+			final EquationsSystem s = new EquationsSystem(this);
-			for (String part : parts) {
+			for (final String part : parts) {
 				s.addFunctionToEnd(parseEquationString(part));
 			}
 			return s;
@@ -48,14 +48,14 @@ public class Calculator {
 	}
 
 	public Function parseEquationString(String string) throws Error {
-		String[] parts = string.split("=");
+		final String[] parts = string.split("=");
 		if (parts.length == 1) {
-			Equation e = new Equation(this, null, null);
+			final Equation e = new Equation(this, null, null);
 			e.setVariable1(new Expression(this, parts[0]));
 			e.setVariable2(new Number(this, BigInteger.ZERO));
 			return e;
 		} else if (parts.length == 2) {
-			Equation e = new Equation(this, null, null);
+			final Equation e = new Equation(this, null, null);
 			e.setVariable1(new Expression(this, parts[0]));
 			e.setVariable2(new Expression(this, parts[1]));
 			return e;
@@ -66,19 +66,19 @@ public class Calculator {
 
 	public ArrayList<Function> solveExpression(ArrayList<Function> input) throws Error {
 		ArrayList<Function> results = new ArrayList<>();
-		ArrayList<Function> partialResults = new ArrayList<>();
+		final ArrayList<Function> partialResults = new ArrayList<>();
-		for (Function f : input) {
+		for (final Function f : input) {
 			if (f instanceof Equation) {
 				throw new IllegalArgumentException("Not an expression!");
 			} else {
 				results.add(f);
 				while (Utils.allSolved(results) == false) {
-					for (Function itm : results) {
+					for (final Function itm : results) {
 						if (itm.isSolved() == false) {
-							long t1 = System.currentTimeMillis();
+							final long t1 = System.currentTimeMillis();
-							List<Function> dt = itm.solveOneStep();
+							final List<Function> dt = itm.solveOneStep();
-							long t2 = System.currentTimeMillis();
+							final long t2 = System.currentTimeMillis();
-							if (t2-t1 >= 3000) {
+							if (t2 - t1 >= 3000) {
 								throw new Error(Errors.TIMEOUT);
 							}
 							partialResults.addAll(dt);
@@ -108,19 +108,19 @@ public class Calculator {
 	}
 
 	public void parseInputString(String eqn) throws Error {
-		ArrayList<Function> fncs = new ArrayList<>();
+		final ArrayList<Function> fncs = new ArrayList<>();
 		if (eqn.length() > 0) {
 			try {
 				fncs.add(parseString(eqn.replace("sqrt", "Ⓐ").replace("^", "Ⓑ")));
-			} catch (Exception ex) {
+			} catch (final Exception ex) {
 
 			}
 		}
 		f = fncs;
-		for (Function f : f) {
+		for (final Function f : f) {
 			try {
 				f.generateGraphics();
-			} catch (NullPointerException ex) {
+			} catch (final NullPointerException ex) {
 				throw new Error(Errors.SYNTAX_ERROR);
 			}
 		}

src/org/warp/picalculator/math/MathematicalSymbols.java

@@ -51,7 +51,7 @@ public class MathematicalSymbols {
 	}
 
 	public static String[] variables() {
-		return new String[] { "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "ⓧ", "Ⓨ", "Z", PI};
+		return new String[] { "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "ⓧ", "Ⓨ", "Z", PI };
 	}
 
 	public static String[] genericSyntax() {
@@ -59,13 +59,6 @@ public class MathematicalSymbols {
 	}
 
 	public static String getGraphicRepresentation(String string) {
-		return string
+		return string.replace("Ⓑ", "^").replace("Ⓒ", "SIN").replace("Ⓓ", "COS").replace("Ⓔ", "TAN").replace("Ⓕ", "ASIN").replace("Ⓖ", "ACOS").replace("Ⓗ", "ATAN");
-				.replace("Ⓑ", "^")
-				.replace("Ⓒ", "SIN")
-				.replace("Ⓓ", "COS")
-				.replace("Ⓔ", "TAN")
-				.replace("Ⓕ", "ASIN")
-				.replace("Ⓖ", "ACOS")
-				.replace("Ⓗ", "ATAN");
 	}
 }

src/org/warp/picalculator/math/functions/AnteriorFunction.java

@@ -4,7 +4,7 @@ import java.util.ArrayList;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 
@@ -12,7 +12,7 @@ import com.rits.cloning.Cloner;
 
 public abstract class AnteriorFunction implements Function {
 	public AnteriorFunction(Function value) {
-		this.root = value.getRoot();
+		root = value.getRoot();
 		variable = value;
 	}
 
@@ -49,20 +49,20 @@ public abstract class AnteriorFunction implements Function {
 	@Override
 	public final ArrayList<Function> solveOneStep() throws Error {
 		final boolean solved = variable.isSolved();
-		ArrayList<Function> result = solved?solve():null;
+		ArrayList<Function> result = solved ? solve() : null;
 
 		if (result == null || result.isEmpty()) {
 			result = new ArrayList<>();
 
-			ArrayList<Function> l1 = new ArrayList<>();
+			final ArrayList<Function> l1 = new ArrayList<>();
 			if (variable.isSolved()) {
 				l1.add(variable);
 			} else {
 				l1.addAll(variable.solveOneStep());
 			}
 
-			for (Function f : l1) {
+			for (final Function f : l1) {
-				result.add(NewInstance(this.root, f));
+				result.add(NewInstance(root, f));
 			}
 		}
 
@@ -83,20 +83,20 @@ public abstract class AnteriorFunction implements Function {
 		variable.setSmall(small);
 		variable.generateGraphics();
 
-		width = PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), getSymbol()) + 1 + getVariable().getWidth();
+		width = DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), getSymbol()) + 1 + getVariable().getWidth();
 		height = variable.getHeight();
 		line = variable.getLine();
 	}
 
 	@Override
 	public void draw(int x, int y) {
-		float h1 = getVariable().getHeight();
+		final float h1 = getVariable().getHeight();
-		int wsegno = PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
+		final int wsegno = DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
-		float hsegno = Utils.getFontHeight(small);
+		final float hsegno = Utils.getFontHeight(small);
-		float maxh = getHeight();
+		final float maxh = getHeight();
-		PIDisplay.renderer.glSetFont(Utils.getFont(small));
+		DisplayManager.renderer.glSetFont(Utils.getFont(small));
 
-		PIDisplay.renderer.glDrawStringLeft(x, (int) Math.floor(y + (maxh - hsegno) / 2), getSymbol());
+		DisplayManager.renderer.glDrawStringLeft(x, (int) Math.floor(y + (maxh - hsegno) / 2), getSymbol());
 		getVariable().draw(x + wsegno + 1, (int) Math.floor(y + (maxh - h1) / 2));
 	}
 
@@ -123,7 +123,7 @@ public abstract class AnteriorFunction implements Function {
 		if (variable != null) {
 			val1 = variable.toString();
 		}
-		return getSymbol()+val1;
+		return getSymbol() + val1;
 //		} catch (Error e) {
 //			return e.id.toString();
 //		}
@@ -131,7 +131,7 @@ public abstract class AnteriorFunction implements Function {
 
 	@Override
 	public AnteriorFunction clone() {
-		Cloner cloner = new Cloner();
+		final Cloner cloner = new Cloner();
 		return cloner.deepClone(this);
 	}
 
@@ -142,7 +142,7 @@ public abstract class AnteriorFunction implements Function {
 
 	@Override
 	public int hashCode() {
-		return variable.hashCode()+883*getSymbol().hashCode();
+		return variable.hashCode() + 883 * getSymbol().hashCode();
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/Division.java

@@ -4,7 +4,7 @@ import java.util.ArrayList;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.MathematicalSymbols;
@@ -29,13 +29,20 @@ public class Division extends FunctionTwoValues {
 		return MathematicalSymbols.DIVISION;
 	}
 
-
 	@Override
 	protected boolean isSolvable() {
-		if (FractionsRule1.compare(this)) return true;
+		if (FractionsRule1.compare(this)) {
-		if (FractionsRule2.compare(this)) return true;
+			return true;
-		if (FractionsRule3.compare(this)) return true;
+		}
-		if (UndefinedRule2.compare(this)) return true;
+		if (FractionsRule2.compare(this)) {
+			return true;
+		}
+		if (FractionsRule3.compare(this)) {
+			return true;
+		}
+		if (UndefinedRule2.compare(this)) {
+			return true;
+		}
 		if (variable1 instanceof Number && variable2 instanceof Number && root.exactMode == false) {
 			return true;
 		}
@@ -54,13 +61,13 @@ public class Division extends FunctionTwoValues {
 		} else if (UndefinedRule2.compare(this)) {
 			result = UndefinedRule2.execute(this);
 		} else if (variable1 instanceof Number && variable2 instanceof Number && root.exactMode == false) {
-			result.add(((Number)variable1).divide((Number)variable2));
+			result.add(((Number) variable1).divide((Number) variable2));
 		}
 		return result;
 	}
 
 	public boolean hasMinus() {
-		String numerator = variable1.toString();
+		final String numerator = variable1.toString();
 		if (numerator.startsWith("-")) {
 			return true;
 		}
@@ -68,7 +75,7 @@ public class Division extends FunctionTwoValues {
 	}
 
 	public void draw(int x, int y, boolean small, boolean drawMinus) {
-		boolean beforedrawminus = this.drawMinus;
+		final boolean beforedrawminus = this.drawMinus;
 		this.drawMinus = drawMinus;
 		draw(x, y);
 		this.drawMinus = beforedrawminus;
@@ -93,8 +100,8 @@ public class Division extends FunctionTwoValues {
 //		glFillRect(x,y,width,height);
 //		glColor3f(0, 0, 0);
 
-		Object var1 = variable1;
+		final Object var1 = variable1;
-		Object var2 = variable2;
+		final Object var2 = variable2;
 		boolean minus = false;
 		int minusw = 0;
 		int minush = 0;
@@ -105,15 +112,15 @@ public class Division extends FunctionTwoValues {
 		}
 		int w1 = 0;
 		int h1 = 0;
-		PIDisplay.renderer.glSetFont(Utils.getFont(small));
+		Utils.getFont(small).use(DisplayManager.display);
 		if (minus) {
-			w1 = PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), numerator);
+			w1 = Utils.getFont(small).getStringWidth(numerator);
-			h1 = Utils.getFont(small).charH;
+			h1 = Utils.getFont(small).getCharacterHeight();
 		} else {
 			w1 = ((Function) var1).getWidth();
 			h1 = ((Function) var1).getHeight();
 		}
-		int w2 = ((Function) var2).getWidth();
+		final int w2 = ((Function) var2).getWidth();
 		int maxw;
 		if (w1 > w2) {
 			maxw = 1 + w1;
@@ -121,15 +128,15 @@ public class Division extends FunctionTwoValues {
 			maxw = 1 + w2;
 		}
 		if (minus && drawMinus) {
-			minusw = PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), "-") + 1;
+			minusw = Utils.getFont(small).getCharacterWidth() /* Width of minus */ + 1;
-			minush = Utils.getFont(small).charH;
+			minush = Utils.getFont(small).getCharacterHeight();
-			PIDisplay.renderer.glDrawStringLeft(x+1, y + h1 + 1 + 1 - (minush / 2), "-");
+			DisplayManager.renderer.glDrawStringLeft(x + 1, y + h1 + 1 + 1 - (minush / 2), "-");
-			PIDisplay.renderer.glDrawStringLeft((int) (x+1 + minusw + 1 + (maxw - w1) / 2d), y, numerator);
+			DisplayManager.renderer.glDrawStringLeft((int) (x + 1 + minusw + 1 + (maxw - w1) / 2d), y, numerator);
 		} else {
-			((Function) var1).draw((int) (x+1 + minusw + (maxw - w1) / 2d), y);
+			((Function) var1).draw((int) (x + 1 + minusw + (maxw - w1) / 2d), y);
 		}
-		((Function) var2).draw((int) (x+1 + minusw + (maxw - w2) / 2d), y + h1 + 1 + 1 + 1);
+		((Function) var2).draw((int) (x + 1 + minusw + (maxw - w2) / 2d), y + h1 + 1 + 1 + 1);
-		PIDisplay.renderer.glFillRect(x+1+ minusw, y + h1 + 1, maxw, 1);
+		DisplayManager.renderer.glFillColor(x + 1 + minusw, y + h1 + 1, maxw, 1);
 	}
 
 	@Override
@@ -152,7 +159,7 @@ public class Division extends FunctionTwoValues {
 		} else {
 			h1 = variable1.getHeight();
 		}
-		int h2 = variable2.getHeight();
+		final int h2 = variable2.getHeight();
 		return h1 + 3 + h2;
 	}
 
@@ -176,19 +183,19 @@ public class Division extends FunctionTwoValues {
 		}
 		int w1 = 0;
 		if (minus) {
-			w1 = PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), numerator);
+			w1 = Utils.getFont(small).getStringWidth(numerator);
 		} else {
 			w1 = variable1.getWidth();
 		}
-		int w2 = variable2.getWidth();
+		final int w2 = variable2.getWidth();
 		int maxw = 0;
 		if (w1 > w2) {
-			maxw = w1+1;
+			maxw = w1 + 1;
 		} else {
-			maxw = w2+1;
+			maxw = w2 + 1;
 		}
 		if (minus && drawMinus) {
-			return 1 + PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), "-") + 1 + maxw;
+			return 1 + Utils.getFont(small).getCharacterWidth() /* Width of minus */ + 1 + maxw;
 		} else {
 			return 1 + maxw;
 		}
@@ -197,7 +204,7 @@ public class Division extends FunctionTwoValues {
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Division) {
-			FunctionTwoValues f = (FunctionTwoValues) o;
+			final FunctionTwoValues f = (FunctionTwoValues) o;
 			return variable1.equals(f.variable1) && variable2.equals(f.variable2);
 		}
 		return false;

src/org/warp/picalculator/math/functions/EmptyNumber.java

@@ -4,7 +4,7 @@ import java.util.List;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 
@@ -39,12 +39,12 @@ public class EmptyNumber implements Function {
 
 	@Override
 	public void draw(int x, int y) {
-		PIDisplay.renderer.glDrawStringLeft(x, y, "␀");
+		DisplayManager.renderer.glDrawStringLeft(x, y, "␀");
 	}
 
 	@Override
 	public int getWidth() {
-		return PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), "␀");
+		return DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), "␀");
 	}
 
 	@Override
@@ -54,7 +54,7 @@ public class EmptyNumber implements Function {
 
 	@Override
 	public int getLine() {
-		return Utils.getFont(small).charH/2;
+		return Utils.getFont(small).charH / 2;
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/Expression.java

@@ -12,7 +12,7 @@ import java.util.regex.Pattern;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.functions.trigonometry.ArcCosine;
@@ -48,7 +48,7 @@ public class Expression extends FunctionMultipleValues {
 		try {
 			new Number(root, string);
 			isNumber = true;
-		} catch (NumberFormatException ex) {
+		} catch (final NumberFormatException ex) {
 			isNumber = false;
 		}
 
@@ -57,10 +57,10 @@ public class Expression extends FunctionMultipleValues {
 
 		isNumber = false; //TODO: rimuovere isNumber, alcune semplificazione come la divisione per zero altrimenti verrebbero saltate.
 
-		if (isNumber){
+		if (isNumber) {
 			// If the expression is already a number:
 			// Se l'espressione è già un numero:
-			Number t = new Number(root, string);
+			final Number t = new Number(root, string);
 			setVariables(new Function[] { t });
 			Utils.debug.println(debugSpaces + "•Result:" + t.toString());
 		} else {
@@ -75,7 +75,7 @@ public class Expression extends FunctionMultipleValues {
 			// Controlla se ci sono più di un uguale (=)
 			int equationsFound = 0;
 			int systemsFound = 0;
-			for (char c : processExpression.toCharArray()) {
+			for (final char c : processExpression.toCharArray()) {
 				if (("" + c).equals(MathematicalSymbols.EQUATION)) {
 					equationsFound += 1;
 				}
@@ -98,7 +98,7 @@ public class Expression extends FunctionMultipleValues {
 			boolean symbolsChanged = false;
 			while (matcher.find()) {
 				symbolsChanged = true;
-				String correzione = "+";
+				final String correzione = "+";
 				processExpression = processExpression.substring(0, matcher.start(0)) + correzione + processExpression.substring(matcher.start(0) + matcher.group(0).length(), processExpression.length());
 				matcher = pattern.matcher(processExpression);
 			}
@@ -109,7 +109,7 @@ public class Expression extends FunctionMultipleValues {
 			matcher = pattern.matcher(processExpression);
 			while (matcher.find()) {
 				symbolsChanged = true;
-				String correzione = "-";
+				final String correzione = "-";
 				processExpression = processExpression.substring(0, matcher.start(0)) + correzione + processExpression.substring(matcher.start(0) + matcher.group(0).length(), processExpression.length());
 				matcher = pattern.matcher(processExpression);
 			}
@@ -138,7 +138,7 @@ public class Expression extends FunctionMultipleValues {
 			symbolsChanged = false;
 			while (matcher.find()) {
 				symbolsChanged = true;
-				String correzione = matcher.group(0).replaceFirst(Matcher.quoteReplacement("+"), "");
+				final String correzione = matcher.group(0).replaceFirst(Matcher.quoteReplacement("+"), "");
 				processExpression = processExpression.substring(0, matcher.start(0) + 1) + correzione + processExpression.substring(matcher.start(0) + matcher.group(0).length(), processExpression.length());
 				matcher = pattern.matcher(processExpression);
 			}
@@ -151,7 +151,7 @@ public class Expression extends FunctionMultipleValues {
 			matcher = pattern.matcher(processExpression);
 			while (matcher.find()) {
 				symbolsChanged = true;
-				String correzione = MathematicalSymbols.MINUS;
+				final String correzione = MathematicalSymbols.MINUS;
 				processExpression = processExpression.substring(0, matcher.start(0) + 1) + correzione + processExpression.substring(matcher.start(0) + 2, processExpression.length());
 				matcher = pattern.matcher(processExpression);
 			}
@@ -186,7 +186,7 @@ public class Expression extends FunctionMultipleValues {
 				symbolsChanged = true;
 				// sistema i segni * impliciti prima e dopo l'espressione.
 				String beforeexp = processExpression.substring(0, matcher.start(0));
-				String newexp = matcher.group(0).substring(1, matcher.group(0).length() - 1);
+				final String newexp = matcher.group(0).substring(1, matcher.group(0).length() - 1);
 				String afterexp = processExpression.substring(matcher.start(0) + matcher.group(0).length(), processExpression.length());
 				if (Pattern.compile("[^\\-" + Utils.ArrayToRegex(Utils.add(concat(MathematicalSymbols.functions(), concat(MathematicalSymbols.signums(true), MathematicalSymbols.genericSyntax())), "(")) + "]$").matcher(beforeexp).find()) {
 					// Se la stringa precedente finisce con un numero
@@ -211,13 +211,13 @@ public class Expression extends FunctionMultipleValues {
 			debugSpaces += "  ";
 
 			// Convert the expression to a list of objects
-			Expression imputRawParenthesis = new Expression(root);
+			final Expression imputRawParenthesis = new Expression(root);
 			imputRawParenthesis.setVariables(new Function[] {});
 			String tmp = "";
 			final String[] functions = concat(concat(concat(concat(MathematicalSymbols.functions(), MathematicalSymbols.parentheses()), MathematicalSymbols.signums(true)), MathematicalSymbols.variables()), MathematicalSymbols.genericSyntax());
 			for (int i = 0; i < processExpression.length(); i++) {
 				// Per ogni carattere cerca se è un numero o una funzione:
-				String charI = processExpression.charAt(i) + "";
+				final String charI = processExpression.charAt(i) + "";
 				if (Utils.isInArray(charI, functions)) {
 
 					// Finds the type of function fron the following list
@@ -326,7 +326,7 @@ public class Expression extends FunctionMultipleValues {
 								Utils.debug.println(debugSpaces + "•Added multiplication to expression:" + new Multiplication(root, null, null).getSymbol());
 							}
 						} else {
-							Function precedentFunction = imputRawParenthesis.getVariable(imputRawParenthesis.getVariablesLength() - 1);
+							final Function precedentFunction = imputRawParenthesis.getVariable(imputRawParenthesis.getVariablesLength() - 1);
 							if (tmp.length() > 0) {
 								if (precedentFunction instanceof Number || precedentFunction instanceof Variable) {
 									imputRawParenthesis.addFunctionToEnd(new Multiplication(root, null, null));
@@ -366,7 +366,7 @@ public class Expression extends FunctionMultipleValues {
 						// Se il carattere è un numero intero, un segno
 						// negativo, o un punto
 						tmp += charI;
-					} catch (Exception exc) {
+					} catch (final Exception exc) {
 						throw new java.lang.RuntimeException("Il carattere " + tmp + charI + " non è nè un numero nè un espressione presente nella lista completa!\nAggiungerlo ad essa o rimuovere il carattere dall'espressione!");
 					}
 				}
@@ -375,7 +375,7 @@ public class Expression extends FunctionMultipleValues {
 				Utils.debug.println(debugSpaces + "•Added variable to expression:" + tmp);
 				try {
 					imputRawParenthesis.addFunctionToEnd(new Number(root, tmp));
-				} catch (NumberFormatException ex) {
+				} catch (final NumberFormatException ex) {
 					throw new Error(Errors.SYNTAX_ERROR);
 				}
 				tmp = "";
@@ -392,9 +392,9 @@ public class Expression extends FunctionMultipleValues {
 			Utils.debug.println(debugSpaces + "•Removing useless parentheses");
 			for (int i = 0; i < imputRawParenthesis.functions.length; i++) {
 				if (imputRawParenthesis.functions[i] instanceof Expression) {
-					Expression par = (Expression) imputRawParenthesis.functions[i];
+					final Expression par = (Expression) imputRawParenthesis.functions[i];
 					if (par.functions.length == 1) {
-						Function subFunz = par.functions[0];
+						final Function subFunz = par.functions[0];
 						if (subFunz instanceof Expression || subFunz instanceof Number || subFunz instanceof Variable) {
 							imputRawParenthesis.functions[i] = subFunz;
 							Utils.debug.println(debugSpaces + "  •Useless parentheses removed");
@@ -406,17 +406,17 @@ public class Expression extends FunctionMultipleValues {
 			// Inizia l'affinazione dell'espressione
 			Utils.debug.println(debugSpaces + "•Pushing classes...");
 
-			Function[] oldFunctionsArray = imputRawParenthesis.getVariables();
+			final Function[] oldFunctionsArray = imputRawParenthesis.getVariables();
-			ArrayList<Function> oldFunctionsList = new ArrayList<>();
+			final ArrayList<Function> oldFunctionsList = new ArrayList<>();
 			for (int i = 0; i < oldFunctionsArray.length; i++) {
 				Function funzione = oldFunctionsArray[i];
 				if (funzione != null) {
 					//Affinazione
 					if (funzione instanceof Root) {
-						if ((i - 1) >= 0 && oldFunctionsArray[i-1] instanceof Number && ((Number)oldFunctionsArray[i-1]).getTerm().compareTo(new BigDecimal(2)) == 0) {
+						if ((i - 1) >= 0 && oldFunctionsArray[i - 1] instanceof Number && ((Number) oldFunctionsArray[i - 1]).getTerm().compareTo(new BigDecimal(2)) == 0) {
 							oldFunctionsArray[i] = null;
-							oldFunctionsArray[i-1] = null;
+							oldFunctionsArray[i - 1] = null;
-							oldFunctionsList.remove(oldFunctionsList.size()-1);
+							oldFunctionsList.remove(oldFunctionsList.size() - 1);
 							i -= 1;
 							funzione = new RootSquare(root, null);
 						}
@@ -452,64 +452,12 @@ public class Expression extends FunctionMultipleValues {
 							oldFunctionsList.set(0, new Multiplication(root, oldFunctionsList.get(0), oldFunctionsList.remove(1)));
 						}
 					}
-					Utils.debug.println(debugSpaces + "  •Phase: "+step);
+					Utils.debug.println(debugSpaces + "  •Phase: " + step);
 					while (i < oldFunctionsList.size() && change == false && oldFunctionsList.size() > 1) {
-						Function funzioneTMP = oldFunctionsList.get(i);
+						final Function funzioneTMP = oldFunctionsList.get(i);
 						if (funzioneTMP instanceof FunctionTwoValues) {
 							if (step != "SN Functions") {
-								if (
+								if ((step == "sums" && (funzioneTMP instanceof Sum || funzioneTMP instanceof SumSubtraction || funzioneTMP instanceof Subtraction) == true && ((funzioneTMP instanceof AnteriorFunction && ((AnteriorFunction) funzioneTMP).variable == null) || (funzioneTMP instanceof FunctionTwoValues && ((FunctionTwoValues) funzioneTMP).variable1 == null && ((FunctionTwoValues) funzioneTMP).variable2 == null) || (!(funzioneTMP instanceof AnteriorFunction) && !(funzioneTMP instanceof FunctionTwoValues)))) || (step.equals("multiplications") && ((funzioneTMP instanceof Multiplication) || (funzioneTMP instanceof Division)) && ((FunctionTwoValues) funzioneTMP).variable1 == null && ((FunctionTwoValues) funzioneTMP).variable2 == null) || (step == "NSN Functions" && (funzioneTMP instanceof Sum) == false && (funzioneTMP instanceof SumSubtraction) == false && (funzioneTMP instanceof Subtraction) == false && (funzioneTMP instanceof Multiplication) == false && (funzioneTMP instanceof Division) == false && ((funzioneTMP instanceof AnteriorFunction && ((AnteriorFunction) funzioneTMP).variable == null) || (funzioneTMP instanceof FunctionTwoValues && ((FunctionTwoValues) funzioneTMP).variable1 == null && ((FunctionTwoValues) funzioneTMP).variable2 == null) || (!(funzioneTMP instanceof AnteriorFunction) && !(funzioneTMP instanceof FunctionTwoValues))))) {
-										(step == "sums" && (funzioneTMP instanceof Sum || funzioneTMP instanceof SumSubtraction || funzioneTMP instanceof Subtraction) == true && ((funzioneTMP instanceof AnteriorFunction && ((AnteriorFunction) funzioneTMP).variable == null) || (funzioneTMP instanceof FunctionTwoValues && ((FunctionTwoValues) funzioneTMP).variable1 == null && ((FunctionTwoValues) funzioneTMP).variable2 == null) || (!(funzioneTMP instanceof AnteriorFunction) && !(funzioneTMP instanceof FunctionTwoValues))))
-										||
-										(
-											step.equals("multiplications")
-											&&
-											(
-												(funzioneTMP instanceof Multiplication)
-												||
-												(funzioneTMP instanceof Division)
-											)
-											&&
-											((FunctionTwoValues) funzioneTMP).variable1 == null
-											&&
-											((FunctionTwoValues) funzioneTMP).variable2 == null
-										)
-										||
-										(
-											step == "NSN Functions"
-											&&
-											(funzioneTMP instanceof Sum) == false
-											&&
-											(funzioneTMP instanceof SumSubtraction) == false
-											&&
-											(funzioneTMP instanceof Subtraction) == false
-											&&
-											(funzioneTMP instanceof Multiplication) == false
-											&&
-											(funzioneTMP instanceof Division) == false
-											&&
-											(
-												(
-													funzioneTMP instanceof AnteriorFunction
-													&&
-													((AnteriorFunction) funzioneTMP).variable == null
-												)
-												||
-												(
-													funzioneTMP instanceof FunctionTwoValues
-													&&
-													((FunctionTwoValues) funzioneTMP).variable1 == null
-													&&
-													((FunctionTwoValues) funzioneTMP).variable2 == null
-												)
-												||
-												(
-													!(funzioneTMP instanceof AnteriorFunction)
-													&&
-													!(funzioneTMP instanceof FunctionTwoValues)
-												)
-											)
-										)
-									) {
 									change = true;
 
 									if (i + 1 < oldFunctionsList.size() && i - 1 >= 0) {
@@ -526,13 +474,13 @@ public class Expression extends FunctionMultipleValues {
 										Utils.debug.println(debugSpaces + "  •Set variable to expression:" + funzioneTMP.getSymbol());
 										try {
 											Utils.debug.println(debugSpaces + "    " + "var1=" + ((FunctionTwoValues) funzioneTMP).getVariable1().toString());
-										} catch (NullPointerException ex2) {}
+										} catch (final NullPointerException ex2) {}
 										try {
 											Utils.debug.println(debugSpaces + "    " + "var2=" + ((FunctionTwoValues) funzioneTMP).getVariable2().toString());
-										} catch (NullPointerException ex2) {}
+										} catch (final NullPointerException ex2) {}
 										try {
 											Utils.debug.println(debugSpaces + "    " + "(result)=" + ((FunctionTwoValues) funzioneTMP).toString());
-										} catch (NullPointerException ex2) {}
+										} catch (final NullPointerException ex2) {}
 
 									} else {
 										throw new Error(Errors.SYNTAX_ERROR);
@@ -542,8 +490,8 @@ public class Expression extends FunctionMultipleValues {
 						} else if (funzioneTMP instanceof AnteriorFunction) {
 							if ((step == "SN Functions" && ((AnteriorFunction) funzioneTMP).variable == null)) {
 								if (i + 1 < oldFunctionsList.size()) {
-									Function nextFunc = oldFunctionsList.get(i + 1);
+									final Function nextFunc = oldFunctionsList.get(i + 1);
-									if (nextFunc instanceof AnteriorFunction && ((AnteriorFunction)nextFunc).variable == null) {
+									if (nextFunc instanceof AnteriorFunction && ((AnteriorFunction) nextFunc).variable == null) {
 
 									} else {
 										change = true;
@@ -556,7 +504,7 @@ public class Expression extends FunctionMultipleValues {
 										oldFunctionsList.remove(i + 1);
 
 										Utils.debug.println(debugSpaces + "  •Set variable to expression:" + funzioneTMP.getSymbol());
-										Function var = ((AnteriorFunction) funzioneTMP).getVariable();
+										final Function var = ((AnteriorFunction) funzioneTMP).getVariable();
 										if (var == null) {
 											Utils.debug.println(debugSpaces + "    " + "var=null");
 										} else {
@@ -580,8 +528,8 @@ public class Expression extends FunctionMultipleValues {
 					}
 				} while (((oldFunctionsList.size() != before || step != "sums") && oldFunctionsList.size() > 1));
 			}
-			if(oldFunctionsList.isEmpty()) {
+			if (oldFunctionsList.isEmpty()) {
-				setVariables(new Function[]{new Number(root, 0)});
+				setVariables(new Function[] { new Number(root, 0) });
 			} else {
 				setVariables(oldFunctionsList);
 			}
@@ -593,7 +541,7 @@ public class Expression extends FunctionMultipleValues {
 			}
 			Utils.debug.println(debugSpaces + "•Finished correcting classes.");
 
-			String result = toString();
+			final String result = toString();
 			Utils.debug.println(debugSpaces + "•Result:" + result);
 		}
 	}
@@ -608,7 +556,7 @@ public class Expression extends FunctionMultipleValues {
 		if (functions.length > 1) {
 			return true;
 		} else if (functions.length == 1) {
-			Function f = functions[0];
+			final Function f = functions[0];
 			if (f.isSolved() == false) {
 				return true;
 			} else {
@@ -620,28 +568,28 @@ public class Expression extends FunctionMultipleValues {
 
 	@Override
 	public List<Function> solveOneStep() throws Error {
-		List<Function> ret = new ArrayList<>();
+		final List<Function> ret = new ArrayList<>();
 		if (functions.length == 1) {
 			if (functions[0].isSolved() || !parenthesisNeeded()) {
 				ret.add(functions[0]);
 				return ret;
 			} else {
-				List<Function> l = functions[0].solveOneStep();
+				final List<Function> l = functions[0].solveOneStep();
-				for (Function f : l) {
+				for (final Function f : l) {
 					if (f instanceof Number || f instanceof Variable) {
 						ret.add(f);
 					} else {
-						ret.add(new Expression(root, new Function[]{f}));
+						ret.add(new Expression(root, new Function[] { f }));
 					}
 				}
 				return ret;
 			}
 		} else {
-			for (Function f : functions) {
+			for (final Function f : functions) {
 				if (f.isSolved() == false) {
-					List<Function> partial = f.solveOneStep();
+					final List<Function> partial = f.solveOneStep();
-					for (Function fnc : partial) {
+					for (final Function fnc : partial) {
-						ret.add(new Expression(root, new Function[]{fnc}));
+						ret.add(new Expression(root, new Function[] { fnc }));
 					}
 				}
 			}
@@ -651,7 +599,7 @@ public class Expression extends FunctionMultipleValues {
 
 	@Override
 	public void generateGraphics() {
-		for (Function var : functions) {
+		for (final Function var : functions) {
 			var.setSmall(small);
 			var.generateGraphics();
 		}
@@ -667,18 +615,16 @@ public class Expression extends FunctionMultipleValues {
 			parenthesisneeded = false;
 		} else {
 			if (functions.length == 1) {
-				Function f = functions[0];
+				final Function f = functions[0];
-				if (f instanceof Number || f instanceof Variable || f instanceof Expression || f instanceof Division || f instanceof Joke
+				if (f instanceof Number || f instanceof Variable || f instanceof Expression || f instanceof Division || f instanceof Joke || f instanceof Undefined || f instanceof Power || f instanceof Sine || f instanceof Cosine || f instanceof Tangent || f instanceof ArcSine || f instanceof ArcCosine || f instanceof ArcTangent) {
-						|| f instanceof Undefined || f instanceof Power || f instanceof Sine || f instanceof Cosine || f instanceof Tangent
-						 || f instanceof ArcSine || f instanceof ArcCosine || f instanceof ArcTangent) {
 					parenthesisneeded = false;
 				}
 				if (f instanceof Multiplication) {
-					if (((Multiplication)f).getVariable1() instanceof Number) {
+					if (((Multiplication) f).getVariable1() instanceof Number) {
-						parenthesisneeded = !(((Multiplication)f).getVariable2() instanceof Variable);
+						parenthesisneeded = !(((Multiplication) f).getVariable2() instanceof Variable);
-					} else if (((Multiplication)f).getVariable2() instanceof Number) {
+					} else if (((Multiplication) f).getVariable2() instanceof Number) {
-						parenthesisneeded = !(((Multiplication)f).getVariable1() instanceof Variable);
+						parenthesisneeded = !(((Multiplication) f).getVariable1() instanceof Variable);
-					} else if (((Multiplication) f).getVariable1() instanceof Variable || ((Multiplication)f).getVariable2() instanceof Variable) {
+					} else if (((Multiplication) f).getVariable1() instanceof Variable || ((Multiplication) f).getVariable2() instanceof Variable) {
 						parenthesisneeded = false;
 					}
 				}
@@ -690,26 +636,26 @@ public class Expression extends FunctionMultipleValues {
 	@Override
 	public void draw(int x, int y) {
 		if (parenthesisNeeded() == false) {
-			this.functions[0].draw(x, y);
+			functions[0].draw(x, y);
 		} else {
-			float miny = y;
+			final float miny = y;
-			float maxy = y + getHeight();
+			final float maxy = y + getHeight();
-			int h = getHeight();
+			final int h = getHeight();
 			x += 1;
-			PIDisplay.renderer.glDrawLine(x, y + 2, x + 2, y);
+			DisplayManager.renderer.glDrawLine(x, y + 2, x + 2, y);
-			PIDisplay.renderer.glDrawLine(x, y + 2, x, y + h - 3);
+			DisplayManager.renderer.glDrawLine(x, y + 2, x, y + h - 3);
-			PIDisplay.renderer.glDrawLine(x, y + h - 3, x + 2, y + h - 1);
+			DisplayManager.renderer.glDrawLine(x, y + h - 3, x + 2, y + h - 1);
 			x += 4;
-			for (Function f : functions) {
+			for (final Function f : functions) {
-				float fheight = f.getHeight();
+				final float fheight = f.getHeight();
-				float y2 = miny + ((maxy - miny) / 2 - fheight / 2);
+				final float y2 = miny + ((maxy - miny) / 2 - fheight / 2);
 				f.draw(x, (int) y2);
 				x += f.getWidth();
 			}
 			x += 2;
-			PIDisplay.renderer.glDrawLine(x, y, x + 2, y + 2);
+			DisplayManager.renderer.glDrawLine(x, y, x + 2, y + 2);
-			PIDisplay.renderer.glDrawLine(x + 2, y + 2, x + 2, y + h - 3);
+			DisplayManager.renderer.glDrawLine(x + 2, y + 2, x + 2, y + h - 3);
-			PIDisplay.renderer.glDrawLine(x, y + h - 1, x + 2, y + h - 3);
+			DisplayManager.renderer.glDrawLine(x, y + h - 1, x + 2, y + h - 3);
 			x += 4;
 		}
 	}
@@ -721,10 +667,10 @@ public class Expression extends FunctionMultipleValues {
 
 	private int calcWidth() {
 		if (parenthesisNeeded() == false) {
-			return this.functions[0].getWidth();
+			return functions[0].getWidth();
 		} else {
 			int w = 0;
-			for (Function f : functions) {
+			for (final Function f : functions) {
 				w += f.getWidth();
 			}
 			return 1 + 4 + w + 2 + 4;
@@ -738,11 +684,11 @@ public class Expression extends FunctionMultipleValues {
 
 	private int calcHeight() {
 		if (initialParenthesis || functions.length == 1) {
-			return this.functions[0].getHeight();
+			return functions[0].getHeight();
 		} else {
 			Function tmin = null;
 			Function tmax = null;
-			for (Function t : functions) {
+			for (final Function t : functions) {
 				if (tmin == null || t.getLine() >= tmin.getLine()) {
 					tmin = t;
 				}
@@ -750,8 +696,9 @@ public class Expression extends FunctionMultipleValues {
 					tmax = t;
 				}
 			}
-			if (tmin == null)
+			if (tmin == null) {
 				return Utils.getFontHeight(small);
+			}
 			return tmin.getLine() + tmax.getHeight() - tmax.getLine();
 		}
 	}
@@ -763,16 +710,17 @@ public class Expression extends FunctionMultipleValues {
 
 	private int calcLine() {
 		if (initialParenthesis || functions.length == 1) {
-			return this.functions[0].getLine();
+			return functions[0].getLine();
 		} else {
 			Function tl = null;
-			for (Function t : functions) {
+			for (final Function t : functions) {
 				if (tl == null || t.getLine() >= tl.getLine()) {
 					tl = t;
 				}
 			}
-			if (tl == null)
+			if (tl == null) {
 				return Utils.getFontHeight(small) / 2;
+			}
 			return tl.getLine();
 		}
 	}
@@ -786,7 +734,7 @@ public class Expression extends FunctionMultipleValues {
 					vars = functions[0].toString();
 				}
 			} else {
-				for (Function variable : functions) {
+				for (final Function variable : functions) {
 					if (variable != null) {
 						vars += ", " + variable.toString();
 					}
@@ -794,15 +742,15 @@ public class Expression extends FunctionMultipleValues {
 				vars = vars.substring(2);
 			}
 		}
-		return "("+vars+")";
+		return "(" + vars + ")";
 	}
 
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Expression) {
-			Expression f = (Expression) o;
+			final Expression f = (Expression) o;
-			Function[] exprFuncs1 = functions;
+			final Function[] exprFuncs1 = functions;
-			Function[] exprFuncs2 = f.functions;
+			final Function[] exprFuncs2 = f.functions;
 			if (exprFuncs1.length == exprFuncs2.length) {
 				for (int i = 0; i < exprFuncs1.length; i++) {
 					if (exprFuncs1[i].equals(exprFuncs2[i]) == false) {
@@ -812,7 +760,7 @@ public class Expression extends FunctionMultipleValues {
 				return true;
 			}
 		} else if (o != null & getVariablesLength() == 1) {
-			Function f = (Function) o;
+			final Function f = (Function) o;
 			return (functions[0].equals(f));
 		} else if (o == null & getVariablesLength() == 0) {
 			return true;

src/org/warp/picalculator/math/functions/FunctionMultipleValues.java

@@ -15,7 +15,7 @@ public abstract class FunctionMultipleValues implements Function {
 
 	public FunctionMultipleValues(Function[] values) {
 		if (values.length > 0) {
-			this.root = values[0].getRoot();
+			root = values[0].getRoot();
 		} else {
 			throw new NullPointerException("Nessun elemento nell'array. Impossibile ricavare il nodo root");
 		}
@@ -39,8 +39,8 @@ public abstract class FunctionMultipleValues implements Function {
 	}
 
 	public void setVariables(final List<Function> value) {
-		int vsize = value.size();
+		final int vsize = value.size();
-		Function[] tmp = new Function[vsize];
+		final Function[] tmp = new Function[vsize];
 		for (int i = 0; i < vsize; i++) {
 			tmp[i] = value.get(i);
 		}
@@ -60,7 +60,7 @@ public abstract class FunctionMultipleValues implements Function {
 	}
 
 	public void addFunctionToEnd(Function value) {
-		int index = functions.length;
+		final int index = functions.length;
 		setVariablesLength(index + 1);
 		functions[index] = value;
 	}
@@ -78,7 +78,7 @@ public abstract class FunctionMultipleValues implements Function {
 
 	@Override
 	public boolean isSolved() {
-		for (Function variable : functions) {
+		for (final Function variable : functions) {
 			if (!variable.isSolved()) {
 				return false;
 			}
@@ -100,7 +100,7 @@ public abstract class FunctionMultipleValues implements Function {
 	public String toString() {
 //		try {
 //			return solve().toString();
-			return "TODO: fare una nuova alternativa a solve().toString()";
+		return "TODO: fare una nuova alternativa a solve().toString()";
 //		} catch (Error e) {
 //			return e.id.toString();
 //		}
@@ -108,7 +108,7 @@ public abstract class FunctionMultipleValues implements Function {
 
 	@Override
 	public Function clone() {
-		Cloner cloner = new Cloner();
+		final Cloner cloner = new Cloner();
 		return cloner.deepClone(this);
 	}
 
@@ -119,7 +119,7 @@ public abstract class FunctionMultipleValues implements Function {
 
 	@Override
 	public int hashCode() {
-		return functions.hashCode()+883*getSymbol().hashCode();
+		return functions.hashCode() + 883 * getSymbol().hashCode();
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/FunctionTwoValues.java

@@ -4,7 +4,7 @@ import java.util.ArrayList;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 
@@ -62,13 +62,13 @@ public abstract class FunctionTwoValues implements Function {
 	@Override
 	public final ArrayList<Function> solveOneStep() throws Error {
 		final boolean solved = variable1.isSolved() & variable2.isSolved();
-		ArrayList<Function> result = solved?solve():null;;
+		ArrayList<Function> result = solved ? solve() : null;;
 
 		if (result == null || result.isEmpty()) {
 			result = new ArrayList<>();
 
-			ArrayList<Function> l1 = new ArrayList<>();
+			final ArrayList<Function> l1 = new ArrayList<>();
-			ArrayList<Function> l2 = new ArrayList<>();
+			final ArrayList<Function> l2 = new ArrayList<>();
 			if (variable1.isSolved()) {
 				l1.add(variable1);
 			} else {
@@ -80,10 +80,10 @@ public abstract class FunctionTwoValues implements Function {
 				l2.addAll(variable2.solveOneStep());
 			}
 
-			Function[][] results = Utils.joinFunctionsResults(l1, l2);
+			final Function[][] results = Utils.joinFunctionsResults(l1, l2);
 
-			for (Function[] f : results) {
+			for (final Function[] f : results) {
-				result.add(NewInstance(this.root, f[0], f[1]));
+				result.add(NewInstance(root, f[0], f[1]));
 			}
 		}
 
@@ -107,14 +107,14 @@ public abstract class FunctionTwoValues implements Function {
 
 	@Override
 	public void draw(int x, int y) {
-		int ln = getLine();
+		final int ln = getLine();
 		int dx = 0;
 		variable1.draw(dx + x, ln - variable1.getLine() + y);
-		dx += 1+variable1.getWidth();
+		dx += 1 + variable1.getWidth();
 		if (drawSignum()) {
-			PIDisplay.renderer.glSetFont(Utils.getFont(small));
+			Utils.getFont(small).use(DisplayManager.display);
-			PIDisplay.renderer.glDrawStringLeft(dx + x, ln - Utils.getFontHeight(small) / 2 + y, getSymbol());
+			DisplayManager.renderer.glDrawStringLeft(dx + x, ln - Utils.getFontHeight(small) / 2 + y, getSymbol());
-			dx += PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
+			dx += Utils.getFont(small).getStringWidth(getSymbol());
 		}
 		variable2.draw(dx + x, ln - variable2.getLine() + y);
 	}
@@ -144,12 +144,12 @@ public abstract class FunctionTwoValues implements Function {
 		if (variable2 != null) {
 			val2 = variable2.toString();
 		}
-		return val1+getSymbol()+val2;
+		return val1 + getSymbol() + val2;
 	}
 
 	@Override
 	public FunctionTwoValues clone() {
-		Cloner cloner = new Cloner();
+		final Cloner cloner = new Cloner();
 		return cloner.deepClone(this);
 	}
 
@@ -163,7 +163,7 @@ public abstract class FunctionTwoValues implements Function {
 	}
 
 	protected int calcWidth() {
-		return variable1.getWidth() + 1 + (drawSignum() ? PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), getSymbol()) : 0) + variable2.getWidth();
+		return variable1.getWidth() + 1 + (drawSignum() ? Utils.getFont(small).getStringWidth(getSymbol()) : 0) + variable2.getWidth();
 	}
 
 	protected int calcHeight() {
@@ -189,7 +189,7 @@ public abstract class FunctionTwoValues implements Function {
 
 	@Override
 	public int hashCode() {
-		return variable1.hashCode()+7*variable2.hashCode()+883*getSymbol().hashCode();
+		return variable1.hashCode() + 7 * variable2.hashCode() + 883 * getSymbol().hashCode();
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/Joke.java

@@ -4,7 +4,7 @@ import java.util.List;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.RAWFont;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
@@ -14,8 +14,8 @@ public class Joke implements Function {
 	public static final byte FISH = 0;
 	public static final byte TORNADO = 1;
 	public static final byte SHARKNADO = 2;
-	private static final String[] jokes =  new String[]{"♓", "TORNADO", "SHARKNADO"};
+	private static final String[] jokes = new String[] { "♓", "TORNADO", "SHARKNADO" };
-	private static final int[] jokesFont =  new int[]{4, -1, -1};
+	private static final int[] jokesFont = new int[] { 4, -1, -1 };
 	private final byte joke;
 	private final Calculator root;
 
@@ -46,29 +46,29 @@ public class Joke implements Function {
 
 	@Override
 	public void draw(int x, int y) {
-		RAWFont rf = PIDisplay.renderer.getCurrentFont();
+		final RAWFont rf = DisplayManager.renderer.getCurrentFont();
 		if (jokesFont[joke] >= 0) {
-			PIDisplay.renderer.glSetFont(PIDisplay.fonts[jokesFont[joke]]);
+			DisplayManager.renderer.glSetFont(DisplayManager.fonts[jokesFont[joke]]);
 		}
-		PIDisplay.renderer.glDrawStringLeft(x, y, jokes[joke]);
+		DisplayManager.renderer.glDrawStringLeft(x, y, jokes[joke]);
 		if (jokesFont[joke] >= 0) {
-			PIDisplay.renderer.glSetFont(rf);
+			DisplayManager.renderer.glSetFont(rf);
 		}
 	}
 
 	@Override
 	public int getWidth() {
 		if (jokesFont[joke] >= 0) {
-			return PIDisplay.renderer.glGetStringWidth(PIDisplay.fonts[jokesFont[joke]], jokes[joke]);
+			return DisplayManager.renderer.glGetStringWidth(DisplayManager.fonts[jokesFont[joke]], jokes[joke]);
 		} else {
-			return PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), jokes[joke]);
+			return DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), jokes[joke]);
 		}
 	}
 
 	@Override
 	public int getHeight() {
 		if (jokesFont[joke] >= 0) {
-			return PIDisplay.fonts[jokesFont[joke]].charH;
+			return DisplayManager.fonts[jokesFont[joke]].charH;
 		} else {
 			return Utils.getFont(small).charH;
 		}
@@ -76,7 +76,7 @@ public class Joke implements Function {
 
 	@Override
 	public int getLine() {
-		return getHeight()/2;
+		return getHeight() / 2;
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/Multiplication.java

@@ -37,12 +37,24 @@ public class Multiplication extends FunctionTwoValues {
 		if (variable1 instanceof Number & variable2 instanceof Number) {
 			return true;
 		}
-		if (SyntaxRule1.compare(this)) return true;
+		if (SyntaxRule1.compare(this)) {
-		if (NumberRule1.compare(this)) return true;
+			return true;
-		if (NumberRule2.compare(this)) return true;
+		}
-		if (NumberRule6.compare(this)) return true;
+		if (NumberRule1.compare(this)) {
-		if (ExponentRule15.compare(this)) return true;
+			return true;
-		if (MultiplicationMethod1.compare(this)) return true;
+		}
+		if (NumberRule2.compare(this)) {
+			return true;
+		}
+		if (NumberRule6.compare(this)) {
+			return true;
+		}
+		if (ExponentRule15.compare(this)) {
+			return true;
+		}
+		if (MultiplicationMethod1.compare(this)) {
+			return true;
+		}
 		return false;
 	}
 
@@ -62,15 +74,15 @@ public class Multiplication extends FunctionTwoValues {
 		} else if (MultiplicationMethod1.compare(this)) {
 			result = MultiplicationMethod1.execute(this);
 		} else if (variable1.isSolved() & variable2.isSolved()) {
-			result.add(((Number)variable1).multiply((Number)variable2));
+			result.add(((Number) variable1).multiply((Number) variable2));
 		}
 		return result;
 	}
 
 	@Override
 	public boolean drawSignum() {
-		Function[] tmpVar = new Function[] { variable1, variable2 };
+		final Function[] tmpVar = new Function[] { variable1, variable2 };
-		boolean[] ok = new boolean[] { false, false };
+		final boolean[] ok = new boolean[] { false, false };
 		for (int val = 0; val < 2; val++) {
 			while (!ok[val]) {
 				if (tmpVar[val] instanceof Division) {
@@ -136,7 +148,7 @@ public class Multiplication extends FunctionTwoValues {
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Multiplication) {
-			FunctionTwoValues f = (FunctionTwoValues) o;
+			final FunctionTwoValues f = (FunctionTwoValues) o;
 			if (variable1.equals(f.variable1) && variable2.equals(f.variable2)) {
 				return true;
 			} else if (variable1.equals(f.variable2) && variable2.equals(f.variable1)) {

src/org/warp/picalculator/math/functions/Negative.java

@@ -5,7 +5,7 @@ import java.util.ArrayList;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.MathematicalSymbols;
@@ -34,15 +34,21 @@ public class Negative extends AnteriorFunction {
 		variable.generateGraphics();
 
 		height = getVariable().getHeight();
-		width = PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), "-") + getVariable().getWidth();
+		width = DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), "-") + getVariable().getWidth();
 		line = getVariable().getLine();
 	}
 
 	@Override
 	protected boolean isSolvable() {
-		if (variable instanceof Number) return true;
+		if (variable instanceof Number) {
-		if (ExpandRule1.compare(this)) return true;
+			return true;
-		if (ExpandRule5.compare(this)) return true;
+		}
+		if (ExpandRule1.compare(this)) {
+			return true;
+		}
+		if (ExpandRule5.compare(this)) {
+			return true;
+		}
 		return false;
 	}
 
@@ -58,24 +64,24 @@ public class Negative extends AnteriorFunction {
 			result = ExpandRule5.execute(this);
 		} else if (variable.isSolved()) {
 			try {
-				Number var = (Number) getVariable();
+				final Number var = (Number) getVariable();
 				result.add(var.multiply(new Number(root, "-1")));
-			} catch(NullPointerException ex) {
+			} catch (final NullPointerException ex) {
 				throw new Error(Errors.ERROR);
-			} catch(NumberFormatException ex) {
+			} catch (final NumberFormatException ex) {
 				throw new Error(Errors.SYNTAX_ERROR);
-			} catch(ArithmeticException ex) {
+			} catch (final ArithmeticException ex) {
 				throw new Error(Errors.NUMBER_TOO_SMALL);
 			}
 		} else {
-			ArrayList<Function> l1 = new ArrayList<>();
+			final ArrayList<Function> l1 = new ArrayList<>();
 			if (variable.isSolved()) {
 				l1.add(variable);
 			} else {
 				l1.addAll(variable.solveOneStep());
 			}
 
-			for (Function f : l1) {
+			for (final Function f : l1) {
 				result.add(new Negative(root, f));
 			}
 		}
@@ -100,7 +106,7 @@ public class Negative extends AnteriorFunction {
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Negative) {
-			return ((Negative)o).variable.equals(variable);
+			return ((Negative) o).variable.equals(variable);
 		}
 		return false;
 	}

src/org/warp/picalculator/math/functions/Number.java

@@ -9,9 +9,8 @@ import java.util.List;
 import org.nevec.rjm.BigDecimalMath;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.RAWFont;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 
 import com.rits.cloning.Cloner;
@@ -72,26 +71,26 @@ public class Number implements Function {
 	}
 
 	public Number add(Number f) {
-		Number ret = new Number(this.root, getTerm().add(f.getTerm()));
+		final Number ret = new Number(root, getTerm().add(f.getTerm()));
 		return ret;
 	}
 
 	public Number multiply(Number f) {
-		Number ret = new Number(this.root, getTerm().multiply(f.getTerm()));
+		final Number ret = new Number(root, getTerm().multiply(f.getTerm()));
 		return ret;
 	}
 
 	public Number divide(Number f) throws Error {
-		Number ret = new Number(this.root, BigDecimalMath.divideRound(getTerm(), f.getTerm()));
+		final Number ret = new Number(root, BigDecimalMath.divideRound(getTerm(), f.getTerm()));
 		return ret;
 	}
 
 	public Number pow(Number f) throws Error {
-		Number ret = new Number(this.root, BigDecimal.ONE);
+		Number ret = new Number(root, BigDecimal.ONE);
 		if (Utils.isIntegerValue(f.term)) {
 			final BigInteger bi = f.term.toBigInteger();
 			for (BigInteger i = BigInteger.ZERO; i.compareTo(bi) < 0; i = i.add(BigInteger.ONE)) {
-				ret = ret.multiply(new Number(this.root, getTerm()));
+				ret = ret.multiply(new Number(root, getTerm()));
 			}
 		} else {
 			ret.term = BigDecimalMath.pow(term, f.term);
@@ -101,20 +100,20 @@ public class Number implements Function {
 
 	@Override
 	public String toString() {
-		String sWith0 = getTerm().setScale(Utils.displayScale, Utils.scaleMode2).toPlainString();
+		final String sWith0 = getTerm().setScale(Utils.displayScale, Utils.scaleMode2).toPlainString();
-		String sExtendedWith0 = getTerm().toPlainString();
+		final String sExtendedWith0 = getTerm().toPlainString();
 		//Remove trailing zeroes. Thanks to Kent, http://stackoverflow.com/questions/14984664/remove-trailing-zero-in-java
 		String s = sWith0.indexOf(".") < 0 ? sWith0 : sWith0.replaceAll("0*$", "").replaceAll("\\.$", "");
-		String sExtended = sExtendedWith0.indexOf(".") < 0 ? sExtendedWith0 : sExtendedWith0.replaceAll("0*$", "").replaceAll("\\.$", "");
+		final String sExtended = sExtendedWith0.indexOf(".") < 0 ? sExtendedWith0 : sExtendedWith0.replaceAll("0*$", "").replaceAll("\\.$", "");
 
 		if (sExtended.length() > s.length()) {
-			s = s+"…";
+			s = s + "…";
 		}
 
 		if (root.exactMode == false) {
-			String cuttedNumber = s.split("\\.")[0];
+			final String cuttedNumber = s.split("\\.")[0];
 			if (cuttedNumber.length() > 8) {
-				return cuttedNumber.substring(0, 1)+","+cuttedNumber.substring(1, 8)+"ℯ℮"+(cuttedNumber.length()-1);
+				return cuttedNumber.substring(0, 1) + "," + cuttedNumber.substring(1, 8) + "ℯ℮" + (cuttedNumber.length() - 1);
 			}
 		}
 		return s;
@@ -131,7 +130,7 @@ public class Number implements Function {
 
 	@Override
 	public void draw(int x, int y) {
-		PIDisplay.renderer.glSetFont(Utils.getFont(small));
+		Utils.getFont(small).use(DisplayManager.display);
 		String t = toString();
 
 		if (t.startsWith("-")) {
@@ -144,20 +143,20 @@ public class Number implements Function {
 		if (t.contains("ℯ℮")) {
 			final RAWFont defaultf = Utils.getFont(small);
 			final RAWFont smallf = Utils.getFont(true);
-			String s = t.substring(0,  t.indexOf("ℯ℮")+2);
+			final String s = t.substring(0, t.indexOf("ℯ℮") + 2);
-			int sw = PIDisplay.renderer.glGetStringWidth(defaultf, s);
+			final int sw = defaultf.getStringWidth(s);
-			PIDisplay.renderer.glDrawStringLeft(x+1, y+smallf.charH-2, s);
+			DisplayManager.renderer.glDrawStringLeft(x + 1, y + smallf.getCharacterHeight() - 2, s);
-			PIDisplay.renderer.glSetFont(smallf);
+			smallf.use(DisplayManager.display);
-			PIDisplay.renderer.glDrawStringLeft(x+1+sw-3, y, t.substring(t.indexOf("ℯ℮")+2));
+			DisplayManager.renderer.glDrawStringLeft(x + 1 + sw - 3, y, t.substring(t.indexOf("ℯ℮") + 2));
 		} else {
-			PIDisplay.renderer.glDrawStringLeft(x+1, y, t);
+			DisplayManager.renderer.glDrawStringLeft(x + 1, y, t);
 		}
 	}
 
 	public int getHeight(boolean drawMinus) {
-		boolean beforedrawminus = this.drawMinus;
+		final boolean beforedrawminus = this.drawMinus;
 		this.drawMinus = drawMinus;
-		int h = getHeight();
+		final int h = getHeight();
 		this.drawMinus = beforedrawminus;
 		return h;
 	}
@@ -168,14 +167,15 @@ public class Number implements Function {
 	}
 
 	private int calcHeight() {
-		String t = toString();
+		final String t = toString();
 		if (t.contains("ℯ℮")) {
-			return Utils.getFontHeight(small)-2+Utils.getFontHeight(true);
+			return Utils.getFontHeight(small) - 2 + Utils.getFontHeight(true);
 		} else {
-			int h1 = Utils.getFontHeight(small);
+			final int h1 = Utils.getFontHeight(small);
 			return h1;
 		}
 	}
+
 	@Override
 	public int getWidth() {
 		return width;
@@ -193,11 +193,11 @@ public class Number implements Function {
 		if (t.contains("ℯ℮")) {
 			final RAWFont defaultf = Utils.getFont(small);
 			final RAWFont smallf = Utils.getFont(true);
-			String s = t.substring(0,  t.indexOf("ℯ℮")+2);
+			final String s = t.substring(0, t.indexOf("ℯ℮") + 2);
-			int sw = PIDisplay.renderer.glGetStringWidth(defaultf, s);
+			final int sw = defaultf.getStringWidth(s);
-			return 1+sw-3+PIDisplay.renderer.glGetStringWidth(smallf, t.substring(t.indexOf("ℯ℮")+2));
+			return 1 + sw - 3 + smallf.getStringWidth(t.substring(t.indexOf("ℯ℮") + 2));
 		} else {
-			return PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), t)+1;
+			return Utils.getFont(small).getStringWidth(t) + 1;
 		}
 	}
 
@@ -207,9 +207,9 @@ public class Number implements Function {
 	}
 
 	private int calcLine() {
-		String t = toString();
+		final String t = toString();
 		if (t.contains("ℯ℮")) {
-			return (Utils.getFontHeight(small) / 2)-2+Utils.getFontHeight(true);
+			return (Utils.getFontHeight(small) / 2) - 2 + Utils.getFontHeight(true);
 		} else {
 			return Utils.getFontHeight(small) / 2;
 		}
@@ -217,7 +217,7 @@ public class Number implements Function {
 
 	@Override
 	public Number clone() {
-		Cloner cloner = new Cloner();
+		final Cloner cloner = new Cloner();
 		return cloner.deepClone(this);
 	}
 
@@ -233,7 +233,7 @@ public class Number implements Function {
 
 	@Override
 	public List<Function> solveOneStep() throws Error {
-		List<Function> result = new ArrayList<>();
+		final List<Function> result = new ArrayList<>();
 		result.add(this);
 		return result;
 	}
@@ -247,9 +247,9 @@ public class Number implements Function {
 	public boolean equals(Object o) {
 		if (o != null & term != null) {
 			if (o instanceof Number) {
-				BigDecimal nav = ((Number) o).getTerm();
+				final BigDecimal nav = ((Number) o).getTerm();
-				boolean na1 = term.compareTo(BigDecimal.ZERO) == 0;
+				final boolean na1 = term.compareTo(BigDecimal.ZERO) == 0;
-				boolean na2 = nav.compareTo(BigDecimal.ZERO) == 0;
+				final boolean na2 = nav.compareTo(BigDecimal.ZERO) == 0;
 				if (na1 == na2) {
 					if (na1 == true) {
 						return true;
@@ -291,41 +291,33 @@ public class Number implements Function {
 		return false;
 	}
 
-	public LinkedList<BigInteger> getFactors()
+	public LinkedList<BigInteger> getFactors() {
-	{
 		BigInteger n = getTerm().toBigIntegerExact();
-	    BigInteger two = BigInteger.valueOf(2);
+		final BigInteger two = BigInteger.valueOf(2);
-	    LinkedList<BigInteger> fs = new LinkedList<>();
+		final LinkedList<BigInteger> fs = new LinkedList<>();
 
-	    if (n.compareTo(two) < 0)
+		if (n.compareTo(two) < 0) {
-	    {
+			throw new IllegalArgumentException("must be greater than one");
-	        throw new IllegalArgumentException("must be greater than one");
+		}
-	    }
 
-	    while (n.mod(two).equals(BigInteger.ZERO))
+		while (n.mod(two).equals(BigInteger.ZERO)) {
-	    {
+			fs.add(two);
-	        fs.add(two);
+			n = n.divide(two);
-	        n = n.divide(two);
+		}
-	    }
 
-	    if (n.compareTo(BigInteger.ONE) > 0)
+		if (n.compareTo(BigInteger.ONE) > 0) {
-	    {
+			BigInteger f = BigInteger.valueOf(3);
-	        BigInteger f = BigInteger.valueOf(3);
+			while (f.multiply(f).compareTo(n) <= 0) {
-	        while (f.multiply(f).compareTo(n) <= 0)
+				if (n.mod(f).equals(BigInteger.ZERO)) {
-	        {
+					fs.add(f);
-	            if (n.mod(f).equals(BigInteger.ZERO))
+					n = n.divide(f);
-	            {
+				} else {
-	                fs.add(f);
+					f = f.add(two);
-	                n = n.divide(f);
+				}
-	            }
+			}
-	            else
+			fs.add(n);
-	            {
+		}
-	                f = f.add(two);
-	            }
-	        }
-	        fs.add(n);
-	    }
 
-	    return fs;
+		return fs;
 	}
 }

src/org/warp/picalculator/math/functions/Power.java

@@ -34,13 +34,27 @@ public class Power extends FunctionTwoValues {
 		if (variable1 instanceof Number & variable2 instanceof Number) {
 			return true;
 		}
-		if (UndefinedRule1.compare(this)) return true;
+		if (UndefinedRule1.compare(this)) {
-		if (ExponentRule1.compare(this)) return true;
+			return true;
-		if (ExponentRule2.compare(this)) return true;
+		}
-		if (ExponentRule3.compare(this)) return true;
+		if (ExponentRule1.compare(this)) {
-		if (ExponentRule4.compare(this)) return true;
+			return true;
-		if (FractionsRule4.compare(this)) return true;
+		}
-		if (FractionsRule5.compare(this)) return true;
+		if (ExponentRule2.compare(this)) {
+			return true;
+		}
+		if (ExponentRule3.compare(this)) {
+			return true;
+		}
+		if (ExponentRule4.compare(this)) {
+			return true;
+		}
+		if (FractionsRule4.compare(this)) {
+			return true;
+		}
+		if (FractionsRule5.compare(this)) {
+			return true;
+		}
 		return false;
 	}
 
@@ -54,12 +68,12 @@ public class Power extends FunctionTwoValues {
 
 		height = variable1.getHeight() + variable2.getHeight() - 4;
 		line = variable2.getHeight() - 4 + variable1.getLine();
-		width = getVariable1().getWidth() + getVariable2().getWidth()+1;
+		width = getVariable1().getWidth() + getVariable2().getWidth() + 1;
 	}
 
 	@Override
 	public ArrayList<Function> solve() throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		if (UndefinedRule1.compare(this)) {
 			result.addAll(UndefinedRule1.execute(this));
 		} else if (ExponentRule1.compare(this)) {
@@ -75,7 +89,7 @@ public class Power extends FunctionTwoValues {
 		} else if (FractionsRule5.compare(this)) {
 			result.addAll(FractionsRule5.execute(this));
 		} else if (variable1 instanceof Number & variable2 instanceof Number) {
-			result.add(((Number)variable1).pow((Number)variable2));
+			result.add(((Number) variable1).pow((Number) variable2));
 		}
 		return result;
 	}
@@ -110,7 +124,7 @@ public class Power extends FunctionTwoValues {
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Power) {
-			FunctionTwoValues f = (FunctionTwoValues) o;
+			final FunctionTwoValues f = (FunctionTwoValues) o;
 			return variable1.equals(f.variable1) && variable2.equals(f.variable2);
 		}
 		return false;

src/org/warp/picalculator/math/functions/Root.java

@@ -5,7 +5,7 @@ import java.math.BigInteger;
 import java.util.ArrayList;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.MathematicalSymbols;
 
@@ -47,8 +47,8 @@ public class Root extends FunctionTwoValues {
 			try {
 				Number exponent = new Number(root, BigDecimal.ONE);
 				exponent = exponent.divide((Number) variable1);
-				Number resultVal = ((Number)variable2).pow(exponent);
+				final Number resultVal = ((Number) variable2).pow(exponent);
-				Number originalVariable = resultVal.pow(new Number(root, 2));
+				final Number originalVariable = resultVal.pow(new Number(root, 2));
 				if (originalVariable.equals(variable2)) {
 					return true;
 				}
@@ -56,7 +56,7 @@ public class Root extends FunctionTwoValues {
 				ex.printStackTrace();
 			}
 		}
-		if (variable1 instanceof Number && ((Number)variable1).equals(new Number(root, 2))) {
+		if (variable1 instanceof Number && ((Number) variable1).equals(new Number(root, 2))) {
 			return true;
 		}
 		return false;
@@ -64,18 +64,18 @@ public class Root extends FunctionTwoValues {
 
 	@Override
 	public ArrayList<Function> solve() throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		if (root.exactMode) {
-			if (variable1 instanceof Number && ((Number)variable1).equals(new Number(root, 2))) {
+			if (variable1 instanceof Number && ((Number) variable1).equals(new Number(root, 2))) {
 				result.add(new RootSquare(root, variable2));
 			} else {
 				Number exponent = new Number(root, BigInteger.ONE);
 				exponent = exponent.divide((Number) variable1);
-				result.add(((Number)variable2).pow(exponent));
+				result.add(((Number) variable2).pow(exponent));
 			}
 		} else {
-			Number exp = (Number) variable1;
+			final Number exp = (Number) variable1;
-			Number numb = (Number) variable2;
+			final Number numb = (Number) variable2;
 
 			result.add(numb.pow(new Number(root, 1).divide(exp)));
 		}
@@ -88,20 +88,20 @@ public class Root extends FunctionTwoValues {
 //		glFillRect(x,y,width,height);
 //		glColor3f(0, 0, 0);
 
-		int w1 = getVariable2().getWidth();
+		final int w1 = getVariable2().getWidth();
-		int h1 = getVariable2().getHeight();
+		final int h1 = getVariable2().getHeight();
-		int w2 = getVariable1().getWidth();
+		final int w2 = getVariable1().getWidth();
-		int h2 = getVariable1().getHeight();
+		final int h2 = getVariable1().getHeight();
-		int height = getHeight();
+		final int height = getHeight();
-		int hh = (int) Math.ceil((double) h1 / 2);
+		final int hh = (int) Math.ceil((double) h1 / 2);
 
 		getVariable1().draw(x + 1, y);
 		getVariable2().draw(x + 1 + w2 + 2, y + h2 - 2);
 
-		PIDisplay.renderer.glDrawLine(x + 1 + w2 - 2, y + height - 3, x + 1 + w2, y + height);
+		DisplayManager.renderer.glDrawLine(x + 1 + w2 - 2, y + height - 3, x + 1 + w2, y + height);
-		PIDisplay.renderer.glDrawLine(x + 1 + w2, y + height - 1 - hh, x + 1 + w2, y + height - 1);
+		DisplayManager.renderer.glDrawLine(x + 1 + w2, y + height - 1 - hh, x + 1 + w2, y + height - 1);
-		PIDisplay.renderer.glDrawLine(x + 1 + w2 + 1, y + height - 2 - h1, x + 1 + w2 + 1, y + height - 1 - hh - 1);
+		DisplayManager.renderer.glDrawLine(x + 1 + w2 + 1, y + height - 2 - h1, x + 1 + w2 + 1, y + height - 1 - hh - 1);
-		PIDisplay.renderer.glDrawLine(x + 1 + w2 + 1, y + height - h1 - 2, x + 1 + w2 + 2 + w1 + 1, y + height - h1 - 2);
+		DisplayManager.renderer.glDrawLine(x + 1 + w2 + 1, y + height - h1 - 2, x + 1 + w2 + 2 + w1 + 1, y + height - h1 - 2);
 	}
 
 	@Override
@@ -122,7 +122,7 @@ public class Root extends FunctionTwoValues {
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Root) {
-			FunctionTwoValues f = (FunctionTwoValues) o;
+			final FunctionTwoValues f = (FunctionTwoValues) o;
 			return variable1.equals(f.variable1) && variable2.equals(f.variable2);
 		}
 		return false;

src/org/warp/picalculator/math/functions/RootSquare.java

@@ -43,8 +43,8 @@ public class RootSquare extends AnteriorFunction {
 			try {
 				Number exponent = new Number(root, BigInteger.ONE);
 				exponent = exponent.divide(new Number(root, 2));
-				Number resultVal = ((Number)variable).pow(exponent);
+				final Number resultVal = ((Number) variable).pow(exponent);
-				Number originalVariable = resultVal.pow(new Number(root, 2));
+				final Number originalVariable = resultVal.pow(new Number(root, 2));
 				if (originalVariable.equals(variable)) {
 					return true;
 				}
@@ -57,14 +57,14 @@ public class RootSquare extends AnteriorFunction {
 
 	@Override
 	public ArrayList<Function> solve() throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		if (root.exactMode) {
 			Number exponent = new Number(root, BigInteger.ONE);
 			exponent = exponent.divide(new Number(root, 2));
-			result.add(((Number)variable).pow(exponent));
+			result.add(((Number) variable).pow(exponent));
 		} else {
-			Number exp = new Number(root, 2);
+			final Number exp = new Number(root, 2);
-			Number numb = (Number) variable;
+			final Number numb = (Number) variable;
 
 			result.add(numb.pow(new Number(root, 1).divide(exp)));
 		}

src/org/warp/picalculator/math/functions/Subtraction.java

@@ -35,14 +35,30 @@ public class Subtraction extends FunctionTwoValues {
 		if (variable1 instanceof Number & variable2 instanceof Number) {
 			return true;
 		}
-		if (VariableRule1.compare(this)) return true;
+		if (VariableRule1.compare(this)) {
-		if (VariableRule2.compare(this)) return true;
+			return true;
-		if (VariableRule3.compare(this)) return true;
+		}
-		if (NumberRule3.compare(this)) return true;
+		if (VariableRule2.compare(this)) {
-		if (ExpandRule1.compare(this)) return true;
+			return true;
-		if (ExpandRule5.compare(this)) return true;
+		}
-		if (NumberRule5.compare(this)) return true;
+		if (VariableRule3.compare(this)) {
-		if (SumMethod1.compare(this)) return true;
+			return true;
+		}
+		if (NumberRule3.compare(this)) {
+			return true;
+		}
+		if (ExpandRule1.compare(this)) {
+			return true;
+		}
+		if (ExpandRule5.compare(this)) {
+			return true;
+		}
+		if (NumberRule5.compare(this)) {
+			return true;
+		}
+		if (SumMethod1.compare(this)) {
+			return true;
+		}
 		return false;
 	}
 
@@ -66,7 +82,7 @@ public class Subtraction extends FunctionTwoValues {
 		} else if (SumMethod1.compare(this)) {
 			result = SumMethod1.execute(this);
 		} else if (variable1.isSolved() & variable2.isSolved()) {
-			result.add(((Number)variable1).add(((Number)variable2).multiply(new Number(root, "-1"))));
+			result.add(((Number) variable1).add(((Number) variable2).multiply(new Number(root, "-1"))));
 		}
 		return result;
 	}
@@ -74,7 +90,7 @@ public class Subtraction extends FunctionTwoValues {
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Subtraction) {
-			FunctionTwoValues f = (FunctionTwoValues) o;
+			final FunctionTwoValues f = (FunctionTwoValues) o;
 			return variable1.equals(f.variable1) && variable2.equals(f.variable2);
 		}
 		return false;

src/org/warp/picalculator/math/functions/Sum.java

@@ -6,7 +6,7 @@ import java.util.ArrayList;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.NumberRule3;
@@ -39,14 +39,30 @@ public class Sum extends FunctionTwoValues {
 		if (variable1 instanceof Number & variable2 instanceof Number) {
 			return true;
 		}
-		if (SyntaxRule2.compare(this)) return true;
+		if (SyntaxRule2.compare(this)) {
-		if (VariableRule1.compare(this)) return true;
+			return true;
-		if (VariableRule2.compare(this)) return true;
+		}
-		if (VariableRule3.compare(this)) return true;
+		if (VariableRule1.compare(this)) {
-		if (NumberRule3.compare(this)) return true;
+			return true;
-		if (NumberRule5.compare(this)) return true;
+		}
-		if (NumberRule7.compare(this)) return true;
+		if (VariableRule2.compare(this)) {
-		if (SumMethod1.compare(this)) return true;
+			return true;
+		}
+		if (VariableRule3.compare(this)) {
+			return true;
+		}
+		if (NumberRule3.compare(this)) {
+			return true;
+		}
+		if (NumberRule5.compare(this)) {
+			return true;
+		}
+		if (NumberRule7.compare(this)) {
+			return true;
+		}
+		if (SumMethod1.compare(this)) {
+			return true;
+		}
 		return false;
 	}
 
@@ -74,18 +90,18 @@ public class Sum extends FunctionTwoValues {
 			result = SumMethod1.execute(this);
 		} else if (variable1.isSolved() & variable2.isSolved()) {
 			if ((root.getChild().equals(this))) {
-				if (((Number)variable1).term.compareTo(new BigDecimal(2)) == 0 && ((Number)variable2).term.compareTo(new BigDecimal(2)) == 0) {
+				if (((Number) variable1).term.compareTo(new BigDecimal(2)) == 0 && ((Number) variable2).term.compareTo(new BigDecimal(2)) == 0) {
 					result.add(new Joke(root, Joke.FISH));
 					return result;
-				} else if (((Number)variable1).term.compareTo(new BigDecimal(20)) == 0 && ((Number)variable2).term.compareTo(new BigDecimal(20)) == 0) {
+				} else if (((Number) variable1).term.compareTo(new BigDecimal(20)) == 0 && ((Number) variable2).term.compareTo(new BigDecimal(20)) == 0) {
 					result.add(new Joke(root, Joke.TORNADO));
 					return result;
-				} else if (((Number)variable1).term.compareTo(new BigDecimal(29)) == 0 && ((Number)variable2).term.compareTo(new BigDecimal(29)) == 0) {
+				} else if (((Number) variable1).term.compareTo(new BigDecimal(29)) == 0 && ((Number) variable2).term.compareTo(new BigDecimal(29)) == 0) {
 					result.add(new Joke(root, Joke.SHARKNADO));
 					return result;
 				}
 			}
-			result.add(((Number)variable1).add((Number)variable2));
+			result.add(((Number) variable1).add((Number) variable2));
 		}
 		return result;
 	}
@@ -113,14 +129,14 @@ public class Sum extends FunctionTwoValues {
 		int dx = 0;
 		dx += variable1.getWidth();
 		dx += 1;
-		dx += PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
+		dx += DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
 		return dx += variable2.getWidth();
 	}
 
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Sum) {
-			FunctionTwoValues f = (FunctionTwoValues) o;
+			final FunctionTwoValues f = (FunctionTwoValues) o;
 			if (variable1.equals(f.variable1) && variable2.equals(f.variable2)) {
 				return true;
 			} else if (variable1.equals(f.variable2) && variable2.equals(f.variable1)) {

src/org/warp/picalculator/math/functions/SumSubtraction.java

@@ -5,7 +5,7 @@ import java.util.ArrayList;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.MathematicalSymbols;
@@ -35,10 +35,18 @@ public class SumSubtraction extends FunctionTwoValues {
 		if (variable1 instanceof Number & variable2 instanceof Number) {
 			return true;
 		}
-		if (NumberRule3.compare(this)) return true;
+		if (NumberRule3.compare(this)) {
-		if (ExpandRule1.compare(this)) return true;
+			return true;
-		if (NumberRule4.compare(this)) return true;
+		}
-		if (NumberRule5.compare(this)) return true;
+		if (ExpandRule1.compare(this)) {
+			return true;
+		}
+		if (NumberRule4.compare(this)) {
+			return true;
+		}
+		if (NumberRule5.compare(this)) {
+			return true;
+		}
 		return false;
 	}
 
@@ -57,8 +65,8 @@ public class SumSubtraction extends FunctionTwoValues {
 		} else if (NumberRule5.compare(this)) {
 			result = NumberRule5.execute(this);
 		} else if (variable1.isSolved() & variable2.isSolved()) {
-			result.add(((Number)variable1).add((Number)variable2));
+			result.add(((Number) variable1).add((Number) variable2));
-			result.add(((Number)variable1).add(((Number)variable2).multiply(new Number(root, "-1"))));
+			result.add(((Number) variable1).add(((Number) variable2).multiply(new Number(root, "-1"))));
 		}
 		return result;
 	}
@@ -82,14 +90,14 @@ public class SumSubtraction extends FunctionTwoValues {
 //		glFillRect(x,y,width,height);
 //		glColor3f(0, 0, 0);
 
-		int ln = getLine();
+		final int ln = getLine();
 		int dx = 0;
 		variable1.draw(dx + x, ln - variable1.getLine() + y);
 		dx += variable1.getWidth();
-		PIDisplay.renderer.glSetFont(Utils.getFont(small));
+		DisplayManager.renderer.glSetFont(Utils.getFont(small));
 		dx += 1;
-		PIDisplay.renderer.glDrawStringLeft(dx + x, ln - Utils.getFontHeight(small) / 2 + y, getSymbol());
+		DisplayManager.renderer.glDrawStringLeft(dx + x, ln - Utils.getFontHeight(small) / 2 + y, getSymbol());
-		dx += PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
+		dx += DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
 		variable2.draw(dx + x, ln - variable2.getLine() + y);
 	}
 
@@ -103,14 +111,14 @@ public class SumSubtraction extends FunctionTwoValues {
 		int dx = 0;
 		dx += variable1.getWidth();
 		dx += 1;
-		dx += PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
+		dx += DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), getSymbol());
 		return dx += variable2.getWidth();
 	}
 
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof SumSubtraction) {
-			FunctionTwoValues f = (FunctionTwoValues) o;
+			final FunctionTwoValues f = (FunctionTwoValues) o;
 			return variable1.equals(f.variable1) && variable2.equals(f.variable2);
 		}
 		return false;

src/org/warp/picalculator/math/functions/Undefined.java

@@ -4,7 +4,7 @@ import java.util.List;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay;
 import org.warp.picalculator.math.Calculator;
 
@@ -36,15 +36,15 @@ public class Undefined implements Function {
 
 	@Override
 	public void generateGraphics() {
-		width = PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), "UNDEFINED");
+		width = DisplayManager.renderer.glGetStringWidth(Utils.getFont(small), "UNDEFINED");
 		height = Utils.getFontHeight(small);
-		line = height/2;
+		line = height / 2;
 	}
 
 	@Override
 	public void draw(int x, int y) {
-		PIDisplay.renderer.glSetFont(Utils.getFont(small));
+		DisplayManager.renderer.glSetFont(Utils.getFont(small));
-		PIDisplay.renderer.glDrawStringLeft(x, y, "UNDEFINED");
+		DisplayManager.renderer.glDrawStringLeft(x, y, "UNDEFINED");
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/Variable.java

@@ -5,7 +5,7 @@ import java.util.List;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.Calculator;
 
 import com.rits.cloning.Cloner;
@@ -50,7 +50,7 @@ public class Variable implements Function {
 
 	@Override
 	public String toString() {
-		return ""+getChar();
+		return "" + getChar();
 	}
 
 //	public void draw(int x, int y, PIDisplay g, boolean small, boolean drawMinus) {
@@ -62,8 +62,8 @@ public class Variable implements Function {
 
 	@Override
 	public void draw(int x, int y) {
-		PIDisplay.renderer.glSetFont(Utils.getFont(small));
+		Utils.getFont(small).use(DisplayManager.display);
-		PIDisplay.renderer.glDrawStringLeft(x+1, y, toString());
+		DisplayManager.renderer.glDrawStringLeft(x + 1, y, toString());
 	}
 
 	@Override
@@ -72,7 +72,7 @@ public class Variable implements Function {
 	}
 
 	private int calcHeight() {
-		int h1 = Utils.getFontHeight(small);
+		final int h1 = Utils.getFontHeight(small);
 		return h1;
 	}
 
@@ -82,7 +82,7 @@ public class Variable implements Function {
 	}
 
 	public int calcWidth() {
-		return PIDisplay.renderer.glGetStringWidth(Utils.getFont(small), toString())+1;
+		return Utils.getFont(small).getStringWidth(toString()) + 1;
 	}
 
 	@Override
@@ -106,7 +106,7 @@ public class Variable implements Function {
 
 	@Override
 	public Variable clone() {
-		Cloner cloner = new Cloner();
+		final Cloner cloner = new Cloner();
 		return cloner.deepClone(this);
 	}
 
@@ -122,7 +122,7 @@ public class Variable implements Function {
 
 	@Override
 	public List<Function> solveOneStep() throws Error {
-		List<Function> result = new ArrayList<>();
+		final List<Function> result = new ArrayList<>();
 		result.add(this);
 		return result;
 	}

src/org/warp/picalculator/math/functions/equations/Equation.java

@@ -21,7 +21,7 @@ import com.rits.cloning.Cloner;
 public class Equation extends FunctionTwoValues {
 
 	public Equation(Calculator root, Function value1, Function value2) {
-		super(root, value1,value2);
+		super(root, value1, value2);
 	}
 
 	@Override
@@ -47,12 +47,12 @@ public class Equation extends FunctionTwoValues {
 		if (variable1 == null || variable2 == null) {
 			throw new Error(Errors.SYNTAX_ERROR);
 		}
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		if (variable1.isSolved() & variable2.isSolved()) {
-			if (((Number)variable2).getTerm().compareTo(new BigDecimal(0)) == 0) {
+			if (((Number) variable2).getTerm().compareTo(new BigDecimal(0)) == 0) {
 				result.add(this);
 			} else {
-				Equation e = new Equation(root, null, null);
+				final Equation e = new Equation(root, null, null);
 				e.setVariable1(new Subtraction(root, variable1, variable2));
 				e.setVariable2(new Number(root, "0"));
 				result.add(e);
@@ -63,7 +63,7 @@ public class Equation extends FunctionTwoValues {
 
 	public List<Function> solve(char variableCharacter) {
 		@SuppressWarnings("unused")
-		ArrayList<Equation> e;
+		final ArrayList<Equation> e;
 		//TODO: WORK IN PROGRESS.
 		//TODO: Finire. Fare in modo che risolva i passaggi fino a che non ce ne sono più
 		return null;
@@ -72,14 +72,14 @@ public class Equation extends FunctionTwoValues {
 	//WORK IN PROGRESS
 	public ArrayList<Equation> solveStep(char charIncognita) {
 		ArrayList<Equation> result = new ArrayList<>();
-		result.add(this.clone());
+		result.add(clone());
-		for (SolveMethod t : SolveMethod.techniques) {
+		for (final SolveMethod t : SolveMethod.techniques) {
-			ArrayList<Equation> newResults = new ArrayList<>();
+			final ArrayList<Equation> newResults = new ArrayList<>();
 			final int sz = result.size();
 			for (int n = 0; n < sz; n++) {
 				newResults.addAll(t.solve(result.get(n)));
 			}
-			Set<Equation> hs = new HashSet<>();
+			final Set<Equation> hs = new HashSet<>();
 			hs.addAll(newResults);
 			newResults.clear();
 			newResults.addAll(hs);
@@ -91,8 +91,14 @@ public class Equation extends FunctionTwoValues {
 
 	@Override
 	public Equation clone() {
-		Cloner cloner = new Cloner();
+		final Cloner cloner = new Cloner();
 		return cloner.deepClone(this);
 	}
 
+	@Override
+	public boolean equals(Object o) {
+		// TODO Auto-generated method stub
+		return false;
+	}
+
 }

src/org/warp/picalculator/math/functions/equations/EquationsSystem.java

@@ -4,7 +4,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.gui.PIDisplay;
+import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.functions.Expression;
 import org.warp.picalculator.math.functions.Function;
@@ -19,7 +19,7 @@ public class EquationsSystem extends FunctionMultipleValues {
 	}
 
 	public EquationsSystem(Calculator root, Function value) {
-		super(root, new Function[]{value});
+		super(root, new Function[] { value });
 	}
 
 	public EquationsSystem(Calculator root, Function[] value) {
@@ -41,28 +41,28 @@ public class EquationsSystem extends FunctionMultipleValues {
 
 	@Override
 	public List<Function> solveOneStep() throws Error {
-		List<Function> ret = new ArrayList<>();
+		final List<Function> ret = new ArrayList<>();
 		if (functions.length == 1) {
 			if (functions[0].isSolved()) {
 				ret.add(functions[0]);
 				return ret;
 			} else {
-				List<Function> l = functions[0].solveOneStep();
+				final List<Function> l = functions[0].solveOneStep();
-				for (Function f : l) {
+				for (final Function f : l) {
 					if (f instanceof Number) {
 						ret.add(f);
 					} else {
-						ret.add(new Expression(this.root, new Function[]{f}));
+						ret.add(new Expression(root, new Function[] { f }));
 					}
 				}
 				return ret;
 			}
 		} else {
-			for (Function f : functions) {
+			for (final Function f : functions) {
 				if (f.isSolved() == false) {
-					List<Function> partial = f.solveOneStep();
+					final List<Function> partial = f.solveOneStep();
-					for (Function fnc : partial) {
+					for (final Function fnc : partial) {
-						ret.add(new Expression(this.root, new Function[]{fnc}));
+						ret.add(new Expression(root, new Function[] { fnc }));
 					}
 				}
 			}
@@ -72,13 +72,13 @@ public class EquationsSystem extends FunctionMultipleValues {
 
 	@Override
 	public void generateGraphics() {
-		for (Function f : functions) {
+		for (final Function f : functions) {
 			f.setSmall(false);
 			f.generateGraphics();
 		}
 
 		width = 0;
-		for (Function f : functions) {
+		for (final Function f : functions) {
 			if (f.getWidth() > width) {
 				width = f.getWidth();
 			}
@@ -86,35 +86,34 @@ public class EquationsSystem extends FunctionMultipleValues {
 		width += 5;
 
 		height = 3;
-		for (Function f : functions) {
+		for (final Function f : functions) {
-			height += f.getHeight()+spacing;
+			height += f.getHeight() + spacing;
 		}
 		height = height - spacing + 2;
 
-		line = height/2;
+		line = height / 2;
 	}
 
 	@Override
 	public void draw(int x, int y) {
 
-		final int h = this.getHeight() - 1;
+		final int h = getHeight() - 1;
 		final int marginTop = 3;
 		final int marginBottom = (h - 3 - 2) / 2 + marginTop;
 		final int spazioSopra = h - marginBottom;
 		int dy = marginTop;
-		for (Function f : functions) {
+		for (final Function f : functions) {
 			f.draw(x + 5, y + dy);
-			dy+=f.getHeight()+spacing;
+			dy += f.getHeight() + spacing;
 		}
 
-		
+		DisplayManager.renderer.glDrawLine(x + 2, y + 0, x + 3, y + 0);
-		PIDisplay.renderer.glDrawLine(x + 2, y + 0, x + 3, y + 0);
+		DisplayManager.renderer.glDrawLine(x + 1, y + 1, x + 1, y + marginBottom / 2);
-		PIDisplay.renderer.glDrawLine(x + 1, y + 1, x + 1, y + marginBottom / 2);
+		DisplayManager.renderer.glDrawLine(x + 2, y + marginBottom / 2 + 1, x + 2, y + marginBottom - 1);
-		PIDisplay.renderer.glDrawLine(x + 2, y + marginBottom / 2 + 1, x + 2, y + marginBottom - 1);
+		DisplayManager.renderer.glDrawLine(x + 0, y + marginBottom, x + 1, y + marginBottom);
-		PIDisplay.renderer.glDrawLine(x + 0, y + marginBottom, x + 1, y + marginBottom);
+		DisplayManager.renderer.glDrawLine(x + 2, y + marginBottom + 1, x + 2, y + marginBottom + spazioSopra / 2 - 1);
-		PIDisplay.renderer.glDrawLine(x + 2, y + marginBottom + 1, x + 2, y + marginBottom + spazioSopra / 2 - 1);
+		DisplayManager.renderer.glDrawLine(x + 1, y + marginBottom + spazioSopra / 2, x + 1, y + h - 1);
-		PIDisplay.renderer.glDrawLine(x + 1, y + marginBottom + spazioSopra / 2, x + 1, y + h - 1);
+		DisplayManager.renderer.glDrawLine(x + 2, y + h, x + 3, y + h);
-		PIDisplay.renderer.glDrawLine(x + 2, y + h, x + 3, y + h);
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/equations/EquationsSystemPart.java

@@ -1,7 +1,5 @@
 package org.warp.picalculator.math.functions.equations;
 
-import static org.warp.picalculator.gui.graphicengine.cpu.CPUDisplay.Render.glDrawLine;
-
 import java.util.ArrayList;
 import java.util.List;
 
@@ -39,7 +37,7 @@ public class EquationsSystemPart extends AnteriorFunction {
 
 	@Override
 	public void draw(int x, int y) {
-		final int h = this.getHeight() - 1;
+		final int h = getHeight() - 1;
 		final int paddingTop = 3;
 		final int spazioSotto = (h - 3 - 2) / 2 + paddingTop;
 		final int spazioSopra = h - spazioSotto;
@@ -67,4 +65,22 @@ public class EquationsSystemPart extends AnteriorFunction {
 	public int getLine() {
 		return line;
 	}
+
+	@Override
+	protected ArrayList<Function> solve() throws Error {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
+	@Override
+	protected boolean isSolvable() {
+		// TODO Auto-generated method stub
+		return false;
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		// TODO Auto-generated method stub
+		return false;
+	}
 }

src/org/warp/picalculator/math/functions/trigonometry/Sine.java

@@ -35,14 +35,14 @@ public class Sine extends AnteriorFunction {
 			}
 		}
 		if (root.angleMode == AngleMode.DEG) {
-			Function[] solvableValues = new Function[]{new Number(root, 0), new Number(root, 30), new Number(root, 90), };
+			final Function[] solvableValues = new Function[] { new Number(root, 0), new Number(root, 30), new Number(root, 90), };
 		}
 		return false;
 	}
 
 	@Override
 	public ArrayList<Function> solve() throws Error {
-		ArrayList<Function> results = new ArrayList<>();
+		final ArrayList<Function> results = new ArrayList<>();
 		if (variable instanceof Number) {
 			if (root.exactMode == false) {
 				results.add(new Number(root, BigDecimalMath.sin(((Number) variable).getTerm())));
@@ -54,7 +54,7 @@ public class Sine extends AnteriorFunction {
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof Sine) {
-			AnteriorFunction f = (AnteriorFunction) o;
+			final AnteriorFunction f = (AnteriorFunction) o;
 			if (variable.equals(f.getVariable())) {
 				return true;
 			}

src/org/warp/picalculator/math/rules/ExpandRule1.java

@@ -16,6 +16,7 @@ import org.warp.picalculator.math.functions.SumSubtraction;
  * Expand rule<br>
  * <b>-(+a+b) = -a-b</b><br>
  * <b>-(+a-b) = -a+b</b>
+ * 
  * @author Andrea Cavalli
  *
  */
@@ -23,9 +24,9 @@ public class ExpandRule1 {
 
 	public static boolean compare(Function f) {
 		if (f instanceof Negative) {
-			Negative fnc = (Negative) f;
+			final Negative fnc = (Negative) f;
 			if (fnc.getVariable() instanceof Expression) {
-				Expression expr = (Expression) fnc.getVariable();
+				final Expression expr = (Expression) fnc.getVariable();
 				if (expr.getVariablesLength() == 1) {
 					if (expr.getVariable(0) instanceof Sum) {
 						return true;
@@ -37,9 +38,9 @@ public class ExpandRule1 {
 				}
 			}
 		} else if (f instanceof Subtraction || f instanceof SumSubtraction) {
-			FunctionTwoValues fnc = (FunctionTwoValues) f;
+			final FunctionTwoValues fnc = (FunctionTwoValues) f;
 			if (fnc.getVariable2() instanceof Expression) {
-				Expression expr = (Expression) fnc.getVariable2();
+				final Expression expr = (Expression) fnc.getVariable2();
 				if (expr.getVariablesLength() == 1) {
 					if (expr.getVariable(0) instanceof Sum) {
 						return true;
@@ -55,16 +56,16 @@ public class ExpandRule1 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
 
 		Expression expr = null;
 		int fromSubtraction = 0;
 		FunctionTwoValues subtraction = null;
 		if (f instanceof Negative) {
-			expr = ((Expression)((Negative) f).getVariable());
+			expr = ((Expression) ((Negative) f).getVariable());
 		} else if (f instanceof Subtraction || f instanceof SumSubtraction) {
-			expr = ((Expression)((FunctionTwoValues) f).getVariable2());
+			expr = ((Expression) ((FunctionTwoValues) f).getVariable2());
 			if (f instanceof Subtraction) {
 				fromSubtraction = 1;
 			} else {
@@ -76,47 +77,47 @@ public class ExpandRule1 {
 
 		}
 
-		Function fnc = expr.getVariable(0);
+		final Function fnc = expr.getVariable(0);
 		if (fnc instanceof Sum) {
-			Function a = ((Sum) fnc).getVariable1();
+			final Function a = ((Sum) fnc).getVariable1();
-			Function b = ((Sum) fnc).getVariable2();
+			final Function b = ((Sum) fnc).getVariable2();
-			Subtraction fnc2 = new Subtraction(root, null, b);
+			final Subtraction fnc2 = new Subtraction(root, null, b);
 			fnc2.setVariable1(new Negative(root, a));
 			if (fromSubtraction > 0) {
 				subtraction = new Subtraction(root, null, null);
-				subtraction.setVariable1(((FunctionTwoValues)f).getVariable1());
+				subtraction.setVariable1(((FunctionTwoValues) f).getVariable1());
 				subtraction.setVariable2(fnc2);
 				result.add(subtraction);
 			} else {
 				result.add(fnc2);
 			}
 		} else if (fnc instanceof Subtraction) {
-			Function a = ((Subtraction) fnc).getVariable1();
+			final Function a = ((Subtraction) fnc).getVariable1();
-			Function b = ((Subtraction) fnc).getVariable2();
+			final Function b = ((Subtraction) fnc).getVariable2();
-			Sum fnc2 = new Sum(root, null, b);
+			final Sum fnc2 = new Sum(root, null, b);
 			fnc2.setVariable1(new Negative(root, a));
 			if (fromSubtraction > 0) {
 				subtraction = new Subtraction(root, null, null);
-				subtraction.setVariable1(((FunctionTwoValues)f).getVariable1());
+				subtraction.setVariable1(((FunctionTwoValues) f).getVariable1());
 				subtraction.setVariable2(fnc2);
 				result.add(subtraction);
 			} else {
 				result.add(fnc2);
 			}
 		} else if (fnc instanceof SumSubtraction) {
-			Function a = ((SumSubtraction) fnc).getVariable1();
+			final Function a = ((SumSubtraction) fnc).getVariable1();
-			Function b = ((SumSubtraction) fnc).getVariable2();
+			final Function b = ((SumSubtraction) fnc).getVariable2();
-			Sum fnc2 = new Sum(root, null, b);
+			final Sum fnc2 = new Sum(root, null, b);
 			fnc2.setVariable1(new Negative(root, a));
-			Subtraction fnc3 = new Subtraction(root, null, b);
+			final Subtraction fnc3 = new Subtraction(root, null, b);
 			fnc3.setVariable1(new Negative(root, a));
 			if (fromSubtraction > 0) {
 				subtraction = new SumSubtraction(root, null, null);
-				subtraction.setVariable1(((FunctionTwoValues)f).getVariable1());
+				subtraction.setVariable1(((FunctionTwoValues) f).getVariable1());
 				subtraction.setVariable2(fnc2);
 				result.add(subtraction);
 				subtraction = new SumSubtraction(root, null, null);
-				subtraction.setVariable1(((FunctionTwoValues)f).getVariable1());
+				subtraction.setVariable1(((FunctionTwoValues) f).getVariable1());
 				subtraction.setVariable2(fnc3);
 				result.add(subtraction);
 				result.add(subtraction);

src/org/warp/picalculator/math/rules/ExpandRule5.java

@@ -3,7 +3,6 @@ package org.warp.picalculator.math.rules;
 import java.util.ArrayList;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.math.Calculator;
 import org.warp.picalculator.math.functions.Expression;
 import org.warp.picalculator.math.functions.Function;
 import org.warp.picalculator.math.functions.Negative;
@@ -12,6 +11,7 @@ import org.warp.picalculator.math.functions.Subtraction;
 /**
  * Expand rule<br>
  * <b>-(-a) = a</b>
+ * 
  * @author Andrea Cavalli
  *
  */
@@ -19,15 +19,15 @@ public class ExpandRule5 {
 
 	public static boolean compare(Function f) {
 		if (f instanceof Negative) {
-			Negative fnc = (Negative) f;
+			final Negative fnc = (Negative) f;
 			if (fnc.getVariable() instanceof Expression) {
-				Expression e = (Expression)fnc.getVariable();
+				final Expression e = (Expression) fnc.getVariable();
 				return e.getVariablesLength() == 1 && e.getVariable(0) instanceof Negative;
 			}
 		} else if (f instanceof Subtraction) {
-			Subtraction fnc = (Subtraction) f;
+			final Subtraction fnc = (Subtraction) f;
 			if (fnc.getVariable2() instanceof Expression) {
-				Expression e = (Expression)fnc.getVariable2();
+				final Expression e = (Expression) fnc.getVariable2();
 				return e.getVariablesLength() == 1 && e.getVariable(0) instanceof Negative;
 			}
 		}
@@ -35,15 +35,15 @@ public class ExpandRule5 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Function a = null;
+		final Function a = null;
 
 		if (f instanceof Negative) {
-			Negative fnc = (Negative) f;
+			final Negative fnc = (Negative) f;
-			result.add(((Negative)((Expression)fnc.getVariable()).getVariable(0)).getVariable());
+			result.add(((Negative) ((Expression) fnc.getVariable()).getVariable(0)).getVariable());
 		} else if (f instanceof Subtraction) {
-			Subtraction fnc = (Subtraction) f;
+			final Subtraction fnc = (Subtraction) f;
-			result.add(((Negative)((Expression)fnc.getVariable2()).getVariable(0)).getVariable());
+			result.add(((Negative) ((Expression) fnc.getVariable2()).getVariable(0)).getVariable());
 		}
 		return result;
 	}

src/org/warp/picalculator/math/rules/ExponentRule1.java

@@ -11,14 +11,15 @@ import org.warp.picalculator.math.functions.Power;
 /**
  * Exponent rule<br>
  * <b>1^a=1</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class ExponentRule1 {
 
 	public static boolean compare(Function f) {
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
 		if (fnc.getVariable1().equals(new Number(root, 1))) {
 			return true;
 		}
@@ -26,8 +27,8 @@ public class ExponentRule1 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		result.add(new Number(root, 1));
 		return result;
 	}

src/org/warp/picalculator/math/rules/ExponentRule15.java

@@ -13,13 +13,14 @@ import org.warp.picalculator.math.functions.Power;
 /**
  * Exponent rule<br>
  * <b>a*a=a^2</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class ExponentRule15 {
 
 	public static boolean compare(Function f) {
-		Multiplication fnc = (Multiplication) f;
+		final Multiplication fnc = (Multiplication) f;
 		if (fnc.getVariable1().equals(fnc.getVariable2())) {
 			return true;
 		}
@@ -27,14 +28,14 @@ public class ExponentRule15 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Multiplication fnc = (Multiplication) f;
+		final Multiplication fnc = (Multiplication) f;
-		Power p = new Power(root, null, null);
+		final Power p = new Power(root, null, null);
-		Expression expr = new Expression(root);
+		final Expression expr = new Expression(root);
-		Function a = fnc.getVariable1();
+		final Function a = fnc.getVariable1();
 		expr.addFunctionToEnd(a);
-		Number two = new Number(root, 2);
+		final Number two = new Number(root, 2);
 		p.setVariable1(expr);
 		p.setVariable2(two);
 		result.add(p);

src/org/warp/picalculator/math/rules/ExponentRule16.java

@@ -14,6 +14,7 @@ import org.warp.picalculator.math.functions.Root;
 /**
  * Exponent rule<br>
  * <b>a√x=x^1/a</b>
+ * 
  * @author Andrea Cavalli
  *
  */
@@ -21,7 +22,7 @@ public class ExponentRule16 {
 
 	public static boolean compare(Function f) {
 		if (f instanceof Root) {
-			Root fnc = (Root) f;
+			final Root fnc = (Root) f;
 			if (fnc.getVariable1().equals(fnc.getVariable2())) {
 				return true;
 			}
@@ -30,14 +31,14 @@ public class ExponentRule16 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Multiplication fnc = (Multiplication) f;
+		final Multiplication fnc = (Multiplication) f;
-		Power p = new Power(fnc.getRoot(), null, null);
+		final Power p = new Power(fnc.getRoot(), null, null);
-		Expression expr = new Expression(root);
+		final Expression expr = new Expression(root);
-		Function a = fnc.getVariable1();
+		final Function a = fnc.getVariable1();
 		expr.addFunctionToEnd(a);
-		Number two = new Number(root, 2);
+		final Number two = new Number(root, 2);
 		p.setVariable1(expr);
 		p.setVariable2(two);
 		result.add(p);

src/org/warp/picalculator/math/rules/ExponentRule2.java

@@ -10,13 +10,14 @@ import org.warp.picalculator.math.functions.Power;
 /**
  * Exponent rule<br>
  * <b>a^1=a</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class ExponentRule2 {
 
 	public static boolean compare(Function f) {
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
 		if (fnc.getVariable2().equals(new Number(f.getRoot(), 1))) {
 			return true;
 		}
@@ -24,8 +25,8 @@ public class ExponentRule2 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		result.add(((Power)f).getVariable1());
+		result.add(((Power) f).getVariable1());
 		return result;
 	}
 

src/org/warp/picalculator/math/rules/ExponentRule3.java

@@ -10,13 +10,14 @@ import org.warp.picalculator.math.functions.Power;
 /**
  * Exponent rule<br>
  * <b>a^0=1</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class ExponentRule3 {
 
 	public static boolean compare(Function f) {
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
 		if (fnc.getVariable2().equals(new Number(f.getRoot(), 0))) {
 			return true;
 		}
@@ -24,7 +25,7 @@ public class ExponentRule3 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		result.add(new Number(f.getRoot(), 1));
 		return result;
 	}

src/org/warp/picalculator/math/rules/ExponentRule4.java

@@ -13,13 +13,14 @@ import org.warp.picalculator.math.functions.Power;
 /**
  * Exponent rule<br>
  * <b>(a*b)^n=a^n*b^n</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class ExponentRule4 {
 
 	public static boolean compare(Function f) {
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
 		if (fnc.getVariable1() instanceof Expression && ((Expression) fnc.getVariable1()).getVariablesLength() == 1 && ((Expression) fnc.getVariable1()).getVariable(0) instanceof Multiplication && fnc.getVariable2() instanceof Number) {
 			return true;
 		}
@@ -27,22 +28,22 @@ public class ExponentRule4 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
-		Expression expr = (Expression) fnc.getVariable1();
+		final Expression expr = (Expression) fnc.getVariable1();
-		Multiplication mult = (Multiplication) expr.getVariable(0);
+		final Multiplication mult = (Multiplication) expr.getVariable(0);
-		Function a = mult.getVariable1();
+		final Function a = mult.getVariable1();
-		Function b = mult.getVariable2();
+		final Function b = mult.getVariable2();
-		Number n = (Number) fnc.getVariable2();
+		final Number n = (Number) fnc.getVariable2();
-		Multiplication retMult = new Multiplication(root, null, null);
+		final Multiplication retMult = new Multiplication(root, null, null);
-		Power p1 = new Power(root, null, null);
+		final Power p1 = new Power(root, null, null);
-		Expression e1 = new Expression(root);
+		final Expression e1 = new Expression(root);
 		e1.addFunctionToEnd(a);
 		p1.setVariable1(e1);
 		p1.setVariable2(n);
-		Power p2 = new Power(root, null, null);
+		final Power p2 = new Power(root, null, null);
-		Expression e2 = new Expression(root);
+		final Expression e2 = new Expression(root);
 		e2.addFunctionToEnd(b);
 		p2.setVariable1(e2);
 		p2.setVariable2(n);

src/org/warp/picalculator/math/rules/FractionsRule1.java

@@ -11,19 +11,20 @@ import org.warp.picalculator.math.functions.Number;
 /**
  * Fractions rule<br>
  * <b>0 / a = 0</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class FractionsRule1 {
 
 	public static boolean compare(Function f) {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		Division fnc = (Division) f;
+		final Division fnc = (Division) f;
 		if (fnc.getVariable1() instanceof Number) {
-			Number numb1 = (Number) fnc.getVariable1();
+			final Number numb1 = (Number) fnc.getVariable1();
 			if (numb1.equals(new Number(root, 0))) {
 				if (fnc.getVariable2() instanceof Number) {
-					Number numb2 = (Number) fnc.getVariable2();
+					final Number numb2 = (Number) fnc.getVariable2();
 					if (numb2.equals(new Number(root, 0))) {
 						return false;
 					}
@@ -35,7 +36,7 @@ public class FractionsRule1 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		result.add(new Number(f.getRoot(), 0));
 		return result;
 	}

src/org/warp/picalculator/math/rules/FractionsRule2.java

@@ -10,15 +10,16 @@ import org.warp.picalculator.math.functions.Number;
 /**
  * Fractions rule<br>
  * <b>a / 1 = a</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class FractionsRule2 {
 
 	public static boolean compare(Function f) {
-		Division fnc = (Division) f;
+		final Division fnc = (Division) f;
 		if (fnc.getVariable2() instanceof Number) {
-			Number numb = (Number) fnc.getVariable2();
+			final Number numb = (Number) fnc.getVariable2();
 			if (numb.equals(new Number(f.getRoot(), 1))) {
 				return true;
 			}
@@ -27,8 +28,8 @@ public class FractionsRule2 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Division fnc = (Division) f;
+		final Division fnc = (Division) f;
 		result.add(fnc.getVariable1());
 		return result;
 	}

src/org/warp/picalculator/math/rules/FractionsRule3.java

@@ -10,13 +10,14 @@ import org.warp.picalculator.math.functions.Number;
 /**
  * Fractions rule<br>
  * <b>a / a = 1</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class FractionsRule3 {
 
 	public static boolean compare(Function f) {
-		Division fnc = (Division) f;
+		final Division fnc = (Division) f;
 		if (fnc.getVariable1().equals(fnc.getVariable2())) {
 			return true;
 		}
@@ -24,7 +25,7 @@ public class FractionsRule3 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		result.add(new Number(f.getRoot(), 1));
 		return result;
 	}

src/org/warp/picalculator/math/rules/FractionsRule4.java

@@ -11,15 +11,16 @@ import org.warp.picalculator.math.functions.Power;
 /**
  * Fractions rule<br>
  * <b>(a / b) ^ -1 = b / a</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class FractionsRule4 {
 
 	public static boolean compare(Function f) {
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
 		if (fnc.getVariable1() instanceof Division && fnc.getVariable2() instanceof Number) {
-			Number n2 = (Number) fnc.getVariable2();
+			final Number n2 = (Number) fnc.getVariable2();
 			if (n2.equals(new Number(f.getRoot(), -1))) {
 				return true;
 			}
@@ -28,11 +29,11 @@ public class FractionsRule4 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
-		Function a = ((Division)fnc.getVariable1()).getVariable1();
+		final Function a = ((Division) fnc.getVariable1()).getVariable1();
-		Function b = ((Division)fnc.getVariable1()).getVariable2();
+		final Function b = ((Division) fnc.getVariable1()).getVariable2();
-		Division res = new Division(f.getRoot(), b, a);
+		final Division res = new Division(f.getRoot(), b, a);
 		result.add(res);
 		return result;
 	}

src/org/warp/picalculator/math/rules/FractionsRule5.java

@@ -1,4 +1,5 @@
 package org.warp.picalculator.math.rules;
+
 import java.math.BigDecimal;
 import java.util.ArrayList;
 
@@ -12,15 +13,16 @@ import org.warp.picalculator.math.functions.Power;
 /**
  * Fractions rule<br>
  * <b>(a / b) ^ -c = (b / a) ^ c</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class FractionsRule5 {
 
 	public static boolean compare(Function f) {
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
 		if (fnc.getVariable1() instanceof Division && fnc.getVariable2() instanceof Number) {
-			Number n2 = (Number) fnc.getVariable2();
+			final Number n2 = (Number) fnc.getVariable2();
 			if (n2.getTerm().compareTo(BigDecimal.ZERO) < 0) {
 				return true;
 			}
@@ -29,14 +31,14 @@ public class FractionsRule5 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
-		Power fnc = (Power) f;
+		final Power fnc = (Power) f;
-		Function a = ((Division)fnc.getVariable1()).getVariable1();
+		final Function a = ((Division) fnc.getVariable1()).getVariable1();
-		Function b = ((Division)fnc.getVariable1()).getVariable2();
+		final Function b = ((Division) fnc.getVariable1()).getVariable2();
-		Function c = ((Number)fnc.getVariable2()).multiply(new Number(root, "-1"));
+		final Function c = ((Number) fnc.getVariable2()).multiply(new Number(root, "-1"));
-		Division dv = new Division(root, b, a);
+		final Division dv = new Division(root, b, a);
-		Power pow = new Power(root, dv, c);
+		final Power pow = new Power(root, dv, c);
 		result.add(pow);
 		return result;
 	}

src/org/warp/picalculator/math/rules/NumberRule1.java

@@ -11,22 +11,23 @@ import org.warp.picalculator.math.functions.Number;
 /**
  * Number rule<br>
  * <b>a * 0 = 0</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class NumberRule1 {
 
 	public static boolean compare(Function f) {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		Multiplication mult = (Multiplication) f;
+		final Multiplication mult = (Multiplication) f;
 		if (mult.getVariable1() instanceof Number) {
-			Number numb = (Number) mult.getVariable1();
+			final Number numb = (Number) mult.getVariable1();
 			if (numb.equals(new Number(root, 0))) {
 				return true;
 			}
 		}
 		if (mult.getVariable2() instanceof Number) {
-			Number numb = (Number) mult.getVariable2();
+			final Number numb = (Number) mult.getVariable2();
 			if (numb.equals(new Number(root, 0))) {
 				return true;
 			}
@@ -35,7 +36,7 @@ public class NumberRule1 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		result.add(new Number(f.getRoot(), "0"));
 		return result;
 	}

src/org/warp/picalculator/math/rules/NumberRule2.java

@@ -11,22 +11,23 @@ import org.warp.picalculator.math.functions.Number;
 /**
  * Number rule<br>
  * <b>a * 1 = a</b>
+ * 
  * @author Andrea Cavalli
  *
  */
 public class NumberRule2 {
 
 	public static boolean compare(Function f) {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		Multiplication mult = (Multiplication) f;
+		final Multiplication mult = (Multiplication) f;
 		if (mult.getVariable1() instanceof Number) {
-			Number numb = (Number) mult.getVariable1();
+			final Number numb = (Number) mult.getVariable1();
 			if (numb.equals(new Number(root, 1))) {
 				return true;
 			}
 		}
 		if (mult.getVariable2() instanceof Number) {
-			Number numb = (Number) mult.getVariable2();
+			final Number numb = (Number) mult.getVariable2();
 			if (numb.equals(new Number(root, 1))) {
 				return true;
 			}
@@ -35,20 +36,20 @@ public class NumberRule2 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		Function a = null;
 		boolean aFound = false;
-		Multiplication mult = (Multiplication) f;
+		final Multiplication mult = (Multiplication) f;
 		if (aFound == false & mult.getVariable1() instanceof Number) {
-			Number numb = (Number) mult.getVariable1();
+			final Number numb = (Number) mult.getVariable1();
 			if (numb.equals(new Number(root, 1))) {
 				a = mult.getVariable2();
 				aFound = true;
 			}
 		}
 		if (aFound == false && mult.getVariable2() instanceof Number) {
-			Number numb = (Number) mult.getVariable2();
+			final Number numb = (Number) mult.getVariable2();
 			if (numb.equals(new Number(root, 1))) {
 				a = mult.getVariable1();
 				aFound = true;

src/org/warp/picalculator/math/rules/NumberRule3.java

@@ -17,6 +17,7 @@ import org.warp.picalculator.math.functions.SumSubtraction;
  * <b>a - a = 0</b><br>
  * <b>-a + a = 0</b><br>
  * <b>a ± a = {0, 2a}</b>
+ * 
  * @author Andrea Cavalli
  *
  */
@@ -24,20 +25,20 @@ public class NumberRule3 {
 
 	public static boolean compare(Function f) {
 		if (f instanceof Subtraction) {
-			Subtraction sub = (Subtraction) f;
+			final Subtraction sub = (Subtraction) f;
 			if (sub.getVariable1().equals(sub.getVariable2())) {
 				return true;
 			}
 		} else if (f instanceof Sum) {
-			Sum sub = (Sum) f;
+			final Sum sub = (Sum) f;
 			if (sub.getVariable1() instanceof Negative) {
-				Negative neg = (Negative) sub.getVariable1();
+				final Negative neg = (Negative) sub.getVariable1();
 				if (neg.getVariable().equals(sub.getVariable2())) {
 					return true;
 				}
 			}
 		} else if (f instanceof SumSubtraction) {
-			SumSubtraction sub = (SumSubtraction) f;
+			final SumSubtraction sub = (SumSubtraction) f;
 			if (sub.getVariable1().equals(sub.getVariable2())) {
 				return true;
 			}
@@ -46,10 +47,10 @@ public class NumberRule3 {
 	}
 
 	public static ArrayList<Function> execute(Function f) throws Error {
-		Calculator root = f.getRoot();
+		final Calculator root = f.getRoot();
-		ArrayList<Function> result = new ArrayList<>();
+		final ArrayList<Function> result = new ArrayList<>();
 		if (f instanceof SumSubtraction) {
-			Multiplication mul = new Multiplication(root, null, null);
+			final Multiplication mul = new Multiplication(root, null, null);
 			mul.setVariable1(new Number(root, 2));
 			mul.setVariable2(f);
 			result.add(mul);