andreacavalli/netty5
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

UnsafeDetectUtil also checks that the Unsafe class has the field theUnsafe to make it work on Android platform.

Browse Source
This commit is contained in:
Johan Rask 2012-01-19 16:14:00 +01:00
parent 59e5f2f262
commit fbb1432e8e
1 changed files with 22 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
common/src/main/java/io/netty/util/UnsafeDetectUtil.java
View File

@ -15,26 +15,44 @@
*/
package io.netty.util;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.concurrent.atomic.AtomicInteger;
/**
* Utility which checks if {@value #UNSAFE} class can be found in the classpath
* and that it can be accessed using "theUnsafe" field which is not true for all platforms, i.e Android
* where it is called "THE_ONE".
*/
public final class UnsafeDetectUtil {
private static final String THE_UNSAFE = "theUnsafe";
private static final String UNSAFE = "sun.misc.Unsafe";
private static final boolean UNSAFE_FOUND = isUnsafeFound(AtomicInteger.class.getClassLoader());
public static boolean isUnsafeFound(ClassLoader loader) {
try {
Class.forName(UNSAFE, true, loader);
return true;
Class<?> unsafeClazz = Class.forName(UNSAFE, true, loader);
return hasUnsafeField(unsafeClazz);
} catch (ClassNotFoundException e) {
return false;
} catch (SecurityException e) {
return false;
} catch (PrivilegedActionException e) {
return false;
}
}
private static boolean hasUnsafeField(final Class<?> unsafeClass) throws PrivilegedActionException {
return AccessController.doPrivileged (new PrivilegedExceptionAction<Boolean>() {
public Boolean run() throws Exception {
unsafeClass.getDeclaredField(THE_UNSAFE);
return true;
}});
}
public static boolean isUnsafeFound() {
return UNSAFE_FOUND;
}