Add Buf.iterateReverse
Motivation: We have the ability to iterate through the bytes in a buffer with the ByteIterator, but another important use case is being able to iterate through the bytes in reverse order. Modification: Add methods for iterating through the bytes in a buffer in reverse order. Also update the copyInto methods to make use of it. Also add a bit of missing javadocs, and argument checks. Result: We can also use ByteIterator for efficiently processing data within a buffer in reverse order.
This commit is contained in:
Chris Vest
parent
68795fb1a5
commit
a63f3e609d
@ -266,7 +266,7 @@ public interface Buf extends Rc<Buf>, BufAccessors {
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/**
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* Iterate the readable bytes of this buffer. The {@linkplain #readerIndex() reader offset} and
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* {@linkplain #writerIndex() witer offset} are not modified by the iterator.
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*
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* <p>
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* Care should be taken to ensure that the buffers lifetime extends beyond the iteration, and the
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* {@linkplain #readerIndex() reader offset} and {@linkplain #writerIndex() writer offset} are not modified while
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* the iteration takes place. Otherwise unpredictable behaviour might result.
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@ -277,5 +277,54 @@ public interface Buf extends Rc<Buf>, BufAccessors {
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return iterate(readerIndex(), readableBytes());
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}
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/**
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* Iterate the given number bytes of this buffer, starting at the given offset.
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* The {@linkplain #readerIndex() reader offset} and {@linkplain #writerIndex() witer offset} are not modified by
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* the iterator.
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* <p>
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* Care should be taken to ensure that the buffers lifetime extends beyond the iteration, and the
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* {@linkplain #readerIndex() reader offset} and {@linkplain #writerIndex() writer offset} are not modified while
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* the iteration takes place. Otherwise unpredictable behaviour might result.
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*
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* @param fromOffset The offset into the buffer where iteration should start.
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* The first byte read from the iterator will be the byte at this offset.
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* @param length The number of bytes to iterate.
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* @return A {@link ByteIterator} for the given stretch of bytes of this buffer.
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* @throws IllegalArgumentException if the length is negative, or if the region given by the {@code fromOffset} and
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* the {@code length} reaches outside of the bounds of this buffer.
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*/
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ByteIterator iterate(int fromOffset, int length);
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/**
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* Iterate the readable bytes of this buffer, in reverse. The {@linkplain #readerIndex() reader offset} and
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* {@linkplain #writerIndex() witer offset} are not modified by the iterator.
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* <p>
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* Care should be taken to ensure that the buffers lifetime extends beyond the iteration, and the
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* {@linkplain #readerIndex() reader offset} and {@linkplain #writerIndex() writer offset} are not modified while
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* the iteration takes place. Otherwise unpredictable behaviour might result.
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*
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* @return A {@link ByteIterator} for the readable bytes of this buffer.
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*/
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default ByteIterator iterateReverse() {
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int woff = writerIndex();
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return iterateReverse(woff == 0? 0 : woff - 1, readableBytes());
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}
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/**
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* Iterate the given number bytes of this buffer, in reverse, starting at the given offset.
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* The {@linkplain #readerIndex() reader offset} and {@linkplain #writerIndex() witer offset} are not modified by
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* the iterator.
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* <p>
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* Care should be taken to ensure that the buffers lifetime extends beyond the iteration, and the
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* {@linkplain #readerIndex() reader offset} and {@linkplain #writerIndex() writer offset} are not modified while
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* the iteration takes place. Otherwise unpredictable behaviour might result.
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*
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* @param fromOffset The offset into the buffer where iteration should start.
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* The first byte read from the iterator will be the byte at this offset.
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* @param length The number of bytes to iterate.
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* @return A {@link ByteIterator} for the given stretch of bytes of this buffer.
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* @throws IllegalArgumentException if the length is negative, or if the region given by the {@code fromOffset} and
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* the {@code length} reaches outside of the bounds of this buffer.
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*/
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ByteIterator iterateReverse(int fromOffset, int length);
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}
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@ -248,6 +248,31 @@ final class CompositeBuf extends RcSupport<Buf, CompositeBuf> implements Buf {
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copyInto(srcPos, (b, s, d, l) -> b.copyInto(s, dest, d, l), destPos, length);
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}
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private void copyInto(int srcPos, CopyInto dest, int destPos, int length) {
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if (length < 0) {
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throw new IndexOutOfBoundsException("Length cannot be negative: " + length + '.');
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}
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if (srcPos < 0) {
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throw indexOutOfBounds(srcPos);
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}
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if (srcPos + length > capacity) {
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throw indexOutOfBounds(srcPos + length);
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}
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while (length > 0) {
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var buf = (Buf) chooseBuffer(srcPos, 0);
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int toCopy = buf.capacity() - subOffset;
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dest.copyInto(buf, subOffset, destPos, toCopy);
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srcPos += toCopy;
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destPos += toCopy;
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length -= toCopy;
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}
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}
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@FunctionalInterface
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private interface CopyInto {
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void copyInto(Buf src, int srcPos, int destPos, int length);
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}
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@Override
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public void copyInto(int srcPos, Buf dest, int destPos, int length) {
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if (length < 0) {
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@ -259,14 +284,39 @@ final class CompositeBuf extends RcSupport<Buf, CompositeBuf> implements Buf {
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if (srcPos + length > capacity) {
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throw indexOutOfBounds(srcPos + length);
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}
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// todo optimise by doing bulk copy via consituent buffers
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for (int i = length - 1; i >= 0; i--) { // Iterate in reverse to account for src and dest buffer overlap.
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dest.writeByte(destPos + i, readByte(srcPos + i));
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// Iterate in reverse to account for src and dest buffer overlap.
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// todo optimise by delegating to constituent buffers.
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var itr = iterateReverse(srcPos + length - 1, length);
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ByteOrder prevOrder = dest.order();
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// We read longs in BE, in reverse, so they need to be flipped for writing.
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dest.order(ByteOrder.LITTLE_ENDIAN);
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try {
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while (itr.hasNextLong()) {
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long val = itr.nextLong();
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length -= Long.BYTES;
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dest.writeLong(destPos + length, val);
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}
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while (itr.hasNextByte()) {
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dest.writeByte(destPos + --length, itr.nextByte());
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}
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} finally {
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dest.order(prevOrder);
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}
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}
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@Override
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public ByteIterator iterate(int fromOffset, int length) {
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if (fromOffset < 0) {
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throw new IllegalArgumentException("The fromOffset cannot be negative: " + fromOffset + '.');
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}
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if (length < 0) {
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throw new IllegalArgumentException("The length cannot be negative: " + length + '.');
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}
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if (capacity < fromOffset + length) {
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throw new IllegalArgumentException("The fromOffset+length is beyond the end of the buffer: " +
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"fromOffset=" + fromOffset + ", length=" + length + '.');
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}
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int startBufferIndex = searchOffsets(fromOffset);
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int off = fromOffset - offsets[startBufferIndex];
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Buf startBuf = bufs[startBufferIndex];
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@ -339,29 +389,87 @@ final class CompositeBuf extends RcSupport<Buf, CompositeBuf> implements Buf {
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};
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}
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private void copyInto(int srcPos, CopyInto dest, int destPos, int length) {
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@Override
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public ByteIterator iterateReverse(int fromOffset, int length) {
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if (fromOffset < 0) {
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throw new IllegalArgumentException("The fromOffset cannot be negative: " + fromOffset + '.');
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}
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if (length < 0) {
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throw new IndexOutOfBoundsException("Length cannot be negative: " + length + '.');
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throw new IllegalArgumentException("The length cannot be negative: " + length + '.');
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}
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if (srcPos < 0) {
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throw indexOutOfBounds(srcPos);
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if (fromOffset - length < -1) {
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throw new IllegalArgumentException("The fromOffset-length would underflow the buffer: " +
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"fromOffset=" + fromOffset + ", length=" + length + '.');
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}
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if (srcPos + length > capacity) {
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throw indexOutOfBounds(srcPos + length);
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}
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while (length > 0) {
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var buf = (Buf) chooseBuffer(srcPos, 0);
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int toCopy = buf.capacity() - subOffset;
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dest.copyInto(buf, subOffset, destPos, toCopy);
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srcPos += toCopy;
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destPos += toCopy;
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length -= toCopy;
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}
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}
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int startBufferIndex = searchOffsets(fromOffset);
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int off = fromOffset - offsets[startBufferIndex];
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Buf startBuf = bufs[startBufferIndex];
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ByteIterator startIterator = startBuf.iterateReverse(off, Math.min(off + 1, length));
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return new ByteIterator() {
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int index = fromOffset;
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final int end = fromOffset - length;
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int bufferIndex = startBufferIndex;
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ByteIterator itr = startIterator;
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@FunctionalInterface
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private interface CopyInto {
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void copyInto(Buf src, int srcPos, int destPos, int length);
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@Override
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public boolean hasNextLong() {
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return bytesLeft() >= Long.BYTES;
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}
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@Override
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public long nextLong() {
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if (itr.hasNextLong()) {
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index -= Long.BYTES;
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return itr.nextLong();
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}
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if (!hasNextLong()) {
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throw new NoSuchElementException();
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}
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return nextLongFromBytes(); // Leave index increments to 'nextByte'
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}
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private long nextLongFromBytes() {
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long val = 0;
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for (int i = 0; i < 8; i++) {
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val <<= 8;
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val |= nextByte();
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}
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return val;
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}
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@Override
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public boolean hasNextByte() {
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return index > end;
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}
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@Override
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public byte nextByte() {
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if (itr.hasNextByte()) {
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byte val = itr.nextByte();
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index--;
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return val;
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}
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if (!hasNextByte()) {
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throw new NoSuchElementException();
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}
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bufferIndex--;
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Buf nextBuf = bufs[bufferIndex];
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itr = nextBuf.iterateReverse(nextBuf.capacity() - 1, Math.min(nextBuf.capacity(), bytesLeft()));
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byte val = itr.nextByte();
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index--;
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return val;
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}
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@Override
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public int currentOffset() {
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return index;
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}
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@Override
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public int bytesLeft() {
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return index - end;
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}
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};
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}
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// <editor-fold defaultstate="collapsed" desc="Primitive accessors.">
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@ -16,8 +16,6 @@
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package io.netty.buffer.b2;
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import io.netty.util.ByteIterator;
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import io.netty.util.ByteProcessor;
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import io.netty.util.internal.PlatformDependent;
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import jdk.incubator.foreign.MemorySegment;
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import java.nio.ByteBuffer;
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@ -155,16 +153,44 @@ class MemSegBuf extends RcSupport<Buf, MemSegBuf> implements Buf {
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}
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}
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private void copyInto(int srcPos, MemorySegment dest, int destPos, int length) {
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dest.asSlice(destPos, length).copyFrom(seg.asSlice(srcPos, length));
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}
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@Override
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public void copyInto(int srcPos, Buf dest, int destPos, int length) {
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// todo optimise: specialise for MemSegBuf; use ByteIterator.
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for (int i = length - 1; i >= 0; i--) { // Iterate in reverse to account for src and dest buffer overlap.
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dest.writeByte(destPos + i, readByte(srcPos + i));
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// todo optimise: specialise for MemSegBuf.
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// Iterate in reverse to account for src and dest buffer overlap.
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var itr = iterateReverse(srcPos + length - 1, length);
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ByteOrder prevOrder = dest.order();
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// We read longs in BE, in reverse, so they need to be flipped for writing.
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dest.order(ByteOrder.LITTLE_ENDIAN);
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try {
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while (itr.hasNextLong()) {
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long val = itr.nextLong();
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length -= Long.BYTES;
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dest.writeLong(destPos + length, val);
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}
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while (itr.hasNextByte()) {
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dest.writeByte(destPos + --length, itr.nextByte());
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}
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} finally {
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dest.order(prevOrder);
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}
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}
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@Override
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public ByteIterator iterate(int fromOffset, int length) {
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if (fromOffset < 0) {
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throw new IllegalArgumentException("The fromOffset cannot be negative: " + fromOffset + '.');
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}
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if (length < 0) {
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throw new IllegalArgumentException("The length cannot be negative: " + length + '.');
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}
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if (seg.byteSize() < fromOffset + length) {
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throw new IllegalArgumentException("The fromOffset+length is beyond the end of the buffer: " +
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"fromOffset=" + fromOffset + ", length=" + length + '.');
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}
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return new ByteIterator() {
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final MemorySegment segment = seg;
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int index = fromOffset;
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@ -178,7 +204,7 @@ class MemSegBuf extends RcSupport<Buf, MemSegBuf> implements Buf {
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@Override
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public long nextLong() {
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if (!hasNextLong()) {
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throw new NoSuchElementException();
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throw new NoSuchElementException("No 'long' value at offet " + currentOffset() + '.');
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}
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long val = getLongAtOffset_BE(segment, index);
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index += Long.BYTES;
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@ -193,7 +219,7 @@ class MemSegBuf extends RcSupport<Buf, MemSegBuf> implements Buf {
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@Override
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public byte nextByte() {
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if (!hasNextByte()) {
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throw new NoSuchElementException();
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throw new NoSuchElementException("No 'byte' value at offet " + currentOffset() + '.');
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}
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byte val = getByteAtOffset_BE(segment, index);
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index++;
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@ -212,8 +238,67 @@ class MemSegBuf extends RcSupport<Buf, MemSegBuf> implements Buf {
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};
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}
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private void copyInto(int srcPos, MemorySegment dest, int destPos, int length) {
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dest.asSlice(destPos, length).copyFrom(seg.asSlice(srcPos, length));
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@Override
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public ByteIterator iterateReverse(int fromOffset, int length) {
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if (fromOffset < 0) {
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throw new IllegalArgumentException("The fromOffset cannot be negative: " + fromOffset + '.');
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}
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if (length < 0) {
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throw new IllegalArgumentException("The length cannot be negative: " + length + '.');
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}
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if (seg.byteSize() <= fromOffset) {
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throw new IllegalArgumentException("The fromOffset is beyond the end of the buffer: " + fromOffset + '.');
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}
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if (fromOffset - length < -1) {
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throw new IllegalArgumentException("The fromOffset-length would underflow the buffer: " +
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"fromOffset=" + fromOffset + ", length=" + length + '.');
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}
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return new ByteIterator() {
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final MemorySegment segment = seg;
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int index = fromOffset;
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final int end = index - length;
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@Override
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public boolean hasNextLong() {
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return index - Long.BYTES >= end;
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}
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@Override
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public long nextLong() {
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if (!hasNextLong()) {
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throw new NoSuchElementException("No 'long' value at offet " + currentOffset() + '.');
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}
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index -= 7;
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long val = getLongAtOffset_LE(segment, index);
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index--;
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return val;
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}
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@Override
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public boolean hasNextByte() {
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return index > end;
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}
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@Override
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public byte nextByte() {
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if (!hasNextByte()) {
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throw new NoSuchElementException("No 'byte' value at offet " + currentOffset() + '.');
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}
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byte val = getByteAtOffset_LE(segment, index);
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index--;
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return val;
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}
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@Override
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public int currentOffset() {
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return index;
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}
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@Override
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public int bytesLeft() {
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return index - end;
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}
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};
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}
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// ### CODEGEN START primitive accessors implementation
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@ -943,6 +943,37 @@ public abstract class BufTest {
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}
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private static void checkByteIterationOfRegion(Buf buf) {
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try {
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buf.iterate(-1, 1);
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fail("Should throw on negative offset.");
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} catch (IllegalArgumentException ignore) {
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// Good.
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}
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try {
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buf.iterate(1, -1);
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fail("Should throw on negative length.");
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} catch (IllegalArgumentException ignore) {
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// Good.
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}
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try {
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buf.iterate(buf.capacity(), 1);
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fail("Should throw on offset overflow.");
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} catch (IllegalArgumentException ignore) {
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// Good.
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}
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try {
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buf.iterate(buf.capacity() - 1, 2);
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fail("Should throw on offset + length overflow.");
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} catch (IllegalArgumentException ignore) {
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// Good.
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}
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try {
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buf.iterate(buf.capacity() - 2, 3);
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fail("Should throw on offset + length overflow.");
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} catch (IllegalArgumentException ignore) {
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// Good.
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}
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var itr = buf.iterate(1, 0);
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assertFalse(itr.hasNextByte());
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assertFalse(itr.hasNextLong());
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@ -1031,8 +1062,230 @@ public abstract class BufTest {
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assertEquals(roff, buf.readerIndex());
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assertEquals(woff, buf.writerIndex());
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}
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// todo reverse iteration
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// todo reverse iteration of region
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@Test
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public void reverseByteIterationOfBigEndianBuffers() {
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try (Buf buf = allocate(0x28)) {
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buf.order(ByteOrder.BIG_ENDIAN); // The byte order should have no impact.
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checkReverseByteIteration(buf);
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buf.reset();
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checkReverseByteIterationOfRegion(buf);
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}
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}
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@Test
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public void reverseByteIterationOfLittleEndianBuffers() {
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try (Buf buf = allocate(0x28)) {
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buf.order(ByteOrder.LITTLE_ENDIAN); // The byte order should have no impact.
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checkReverseByteIteration(buf);
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buf.reset();
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checkReverseByteIterationOfRegion(buf);
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}
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}
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private static void checkReverseByteIteration(Buf buf) {
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var itr = buf.iterateReverse();
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assertFalse(itr.hasNextByte());
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assertFalse(itr.hasNextLong());
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assertEquals(0, itr.bytesLeft());
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try {
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itr.nextLong();
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fail("Expected a no such element exception.");
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} catch (NoSuchElementException ignore) {
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// Good.
|
||||
}
|
||||
try {
|
||||
itr.nextByte();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
|
||||
for (int i = 0; i < 0x27; i++) {
|
||||
buf.writeByte((byte) (i + 1));
|
||||
}
|
||||
int roff = buf.readerIndex();
|
||||
int woff = buf.writerIndex();
|
||||
itr = buf.iterateReverse();
|
||||
assertEquals(0x27, itr.bytesLeft());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x2726252423222120L, itr.nextLong());
|
||||
assertEquals(0x1F, itr.bytesLeft());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x1F1E1D1C1B1A1918L, itr.nextLong());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x17, itr.bytesLeft());
|
||||
assertEquals(0x1716151413121110L, itr.nextLong());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x0F, itr.bytesLeft());
|
||||
assertEquals(0x0F0E0D0C0B0A0908L, itr.nextLong());
|
||||
assertFalse(itr.hasNextLong());
|
||||
assertEquals(7, itr.bytesLeft());
|
||||
try {
|
||||
itr.nextLong();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals((byte) 0x07, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(6, itr.bytesLeft());
|
||||
assertEquals((byte) 0x06, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(5, itr.bytesLeft());
|
||||
assertEquals((byte) 0x05, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(4, itr.bytesLeft());
|
||||
assertEquals((byte) 0x04, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(3, itr.bytesLeft());
|
||||
assertEquals((byte) 0x03, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(2, itr.bytesLeft());
|
||||
assertEquals((byte) 0x02, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(1, itr.bytesLeft());
|
||||
assertEquals((byte) 0x01, itr.nextByte());
|
||||
assertFalse(itr.hasNextByte());
|
||||
assertEquals(0, itr.bytesLeft());
|
||||
try {
|
||||
itr.nextLong();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
try {
|
||||
itr.nextByte();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
assertEquals(roff, buf.readerIndex());
|
||||
assertEquals(woff, buf.writerIndex());
|
||||
}
|
||||
|
||||
private static void checkReverseByteIterationOfRegion(Buf buf) {
|
||||
try {
|
||||
buf.iterateReverse(-1, 0);
|
||||
fail("Should throw on negative offset.");
|
||||
} catch (IllegalArgumentException ignore) {
|
||||
// Good.
|
||||
}
|
||||
try {
|
||||
buf.iterateReverse(0, -1);
|
||||
fail("Should throw on negative length.");
|
||||
} catch (IllegalArgumentException ignore) {
|
||||
// Good.
|
||||
}
|
||||
try {
|
||||
buf.iterateReverse(0, 2);
|
||||
fail("Should throw on offset + length underflow.");
|
||||
} catch (IllegalArgumentException ignore) {
|
||||
// Good.
|
||||
}
|
||||
try {
|
||||
buf.iterateReverse(1, 3);
|
||||
fail("Should throw on offset + length underflow.");
|
||||
} catch (IllegalArgumentException ignore) {
|
||||
// Good.
|
||||
}
|
||||
try {
|
||||
buf.iterateReverse(buf.capacity(), 0);
|
||||
fail("Should throw on offset overflow.");
|
||||
} catch (IllegalArgumentException ignore) {
|
||||
// Good.
|
||||
}
|
||||
|
||||
var itr = buf.iterateReverse(1, 0);
|
||||
assertFalse(itr.hasNextByte());
|
||||
assertFalse(itr.hasNextLong());
|
||||
assertEquals(0, itr.bytesLeft());
|
||||
try {
|
||||
itr.nextLong();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
try {
|
||||
itr.nextByte();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
|
||||
for (int i = 0; i < 0x27; i++) {
|
||||
buf.writeByte((byte) (i + 1));
|
||||
}
|
||||
int roff = buf.readerIndex();
|
||||
int woff = buf.writerIndex();
|
||||
itr = buf.iterateReverse(buf.writerIndex() - 2, buf.readableBytes() - 2);
|
||||
assertEquals(0x25, itr.bytesLeft());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x262524232221201FL, itr.nextLong());
|
||||
assertEquals(0x1D, itr.bytesLeft());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x1E1D1C1B1A191817L, itr.nextLong());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x15, itr.bytesLeft());
|
||||
assertEquals(0x161514131211100FL, itr.nextLong());
|
||||
assertTrue(itr.hasNextLong());
|
||||
assertEquals(0x0D, itr.bytesLeft());
|
||||
assertEquals(0x0E0D0C0B0A090807L, itr.nextLong());
|
||||
assertFalse(itr.hasNextLong());
|
||||
assertEquals(5, itr.bytesLeft());
|
||||
try {
|
||||
itr.nextLong();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals((byte) 0x06, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(4, itr.bytesLeft());
|
||||
assertEquals((byte) 0x05, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(3, itr.bytesLeft());
|
||||
assertEquals((byte) 0x04, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(2, itr.bytesLeft());
|
||||
assertEquals((byte) 0x03, itr.nextByte());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertEquals(1, itr.bytesLeft());
|
||||
assertEquals((byte) 0x02, itr.nextByte());
|
||||
assertFalse(itr.hasNextByte());
|
||||
assertEquals(0, itr.bytesLeft());
|
||||
try {
|
||||
itr.nextLong();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
try {
|
||||
itr.nextByte();
|
||||
fail("Expected a no such element exception.");
|
||||
} catch (NoSuchElementException ignore) {
|
||||
// Good.
|
||||
}
|
||||
|
||||
itr = buf.iterateReverse(buf.readerIndex() + 2, 2);
|
||||
assertEquals(2, itr.bytesLeft());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertFalse(itr.hasNextLong());
|
||||
assertEquals((byte) 0x03, itr.nextByte());
|
||||
assertEquals(1, itr.bytesLeft());
|
||||
assertTrue(itr.hasNextByte());
|
||||
assertFalse(itr.hasNextLong());
|
||||
assertEquals((byte) 0x02, itr.nextByte());
|
||||
assertEquals(0, itr.bytesLeft());
|
||||
assertFalse(itr.hasNextByte());
|
||||
assertFalse(itr.hasNextLong());
|
||||
assertEquals(roff, buf.readerIndex());
|
||||
assertEquals(woff, buf.writerIndex());
|
||||
}
|
||||
|
||||
// todo resize copying must preserve contents
|
||||
// todo resize sharing
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user