Merge pull request #61 from netty/composite-split

Add splitComponentsFloor and splitComponentsCeil
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Chris Vest 2021-05-07 17:27:15 +02:00 committed by GitHub
commit ccaed0ae7b
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3 changed files with 308 additions and 4 deletions

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@ -607,7 +607,8 @@ public interface Buffer extends Rc<Buffer>, BufferAccessors {
* See the <a href="#slice-split">Slice vs. Split</a> section for details on the difference between slice * See the <a href="#slice-split">Slice vs. Split</a> section for details on the difference between slice
* and split. * and split.
* *
* @return A new buffer with independent and exclusive ownership over the read and readable bytes from this buffer. * @return A new buffer with independent and exclusive ownership over the bytes from the beginning to the given
* offset of this buffer.
*/ */
Buffer split(int splitOffset); Buffer split(int splitOffset);

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@ -921,8 +921,7 @@ public final class CompositeBuffer extends RcSupport<Buffer, CompositeBuffer> im
computeBufferOffsets(); computeBufferOffsets();
} }
@Override private void checkSplit(int splitOffset) {
public CompositeBuffer split(int splitOffset) {
if (splitOffset < 0) { if (splitOffset < 0) {
throw new IllegalArgumentException("The split offset cannot be negative: " + splitOffset + '.'); throw new IllegalArgumentException("The split offset cannot be negative: " + splitOffset + '.');
} }
@ -933,6 +932,11 @@ public final class CompositeBuffer extends RcSupport<Buffer, CompositeBuffer> im
if (!isOwned()) { if (!isOwned()) {
throw new IllegalStateException("Cannot split a buffer that is not owned."); throw new IllegalStateException("Cannot split a buffer that is not owned.");
} }
}
@Override
public CompositeBuffer split(int splitOffset) {
checkSplit(splitOffset);
if (bufs.length == 0) { if (bufs.length == 0) {
// Splitting a zero-length buffer is trivial. // Splitting a zero-length buffer is trivial.
return new CompositeBuffer(allocator, bufs, unsafeGetDrop(), true).order(order); return new CompositeBuffer(allocator, bufs, unsafeGetDrop(), true).order(order);
@ -946,6 +950,10 @@ public final class CompositeBuffer extends RcSupport<Buffer, CompositeBuffer> im
splits[splits.length - 1] = bufs[0].split(off); splits[splits.length - 1] = bufs[0].split(off);
} }
computeBufferOffsets(); computeBufferOffsets();
return buildSplitBuffer(splits);
}
private CompositeBuffer buildSplitBuffer(Buffer[] splits) {
try { try {
var compositeBuf = new CompositeBuffer(allocator, splits, unsafeGetDrop(), true); var compositeBuf = new CompositeBuffer(allocator, splits, unsafeGetDrop(), true);
compositeBuf.order = order; // Preserve byte order even if splits array is empty. compositeBuf.order = order; // Preserve byte order even if splits array is empty.
@ -958,6 +966,62 @@ public final class CompositeBuffer extends RcSupport<Buffer, CompositeBuffer> im
} }
} }
/**
* Split this buffer at a component boundary that is less than or equal to the given offset.
* <p>
* This method behaves the same as {@link #split(int)}, except no components are split.
*
* @param splitOffset The maximum split offset. The real split offset will be at a component boundary that is less
* than or equal to this offset.
* @return A new buffer with independent and exclusive ownership over the bytes from the beginning to a component
* boundary less than or equal to the given offset of this buffer.
*/
public CompositeBuffer splitComponentsFloor(int splitOffset) {
checkSplit(splitOffset);
if (bufs.length == 0) {
// Splitting a zero-length buffer is trivial.
return new CompositeBuffer(allocator, bufs, unsafeGetDrop(), true).order(order);
}
int i = searchOffsets(splitOffset);
int off = splitOffset - offsets[i];
if (off == bufs[i].capacity()) {
i++;
}
Buffer[] splits = Arrays.copyOf(bufs, i);
bufs = Arrays.copyOfRange(bufs, i, bufs.length);
computeBufferOffsets();
return buildSplitBuffer(splits);
}
/**
* Split this buffer at a component boundary that is greater than or equal to the given offset.
* <p>
* This method behaves the same as {@link #split(int)}, except no components are split.
*
* @param splitOffset The minimum split offset. The real split offset will be at a component boundary that is
* greater than or equal to this offset.
* @return A new buffer with independent and exclusive ownership over the bytes from the beginning to a component
* boundary greater than or equal to the given offset of this buffer.
*/
public CompositeBuffer splitComponentsCeil(int splitOffset) {
checkSplit(splitOffset);
if (bufs.length == 0) {
// Splitting a zero-length buffer is trivial.
return new CompositeBuffer(allocator, bufs, unsafeGetDrop(), true).order(order);
}
int i = searchOffsets(splitOffset);
int off = splitOffset - offsets[i];
if (0 < off && off <= bufs[i].capacity()) {
i++;
}
Buffer[] splits = Arrays.copyOf(bufs, i);
bufs = Arrays.copyOfRange(bufs, i, bufs.length);
computeBufferOffsets();
return buildSplitBuffer(splits);
}
@Override @Override
public void compact() { public void compact() {
if (!isOwned()) { if (!isOwned()) {

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@ -29,7 +29,6 @@ import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.junit.jupiter.api.Assertions.assertTrue; import static org.junit.jupiter.api.Assertions.assertTrue;
public class BufferCompositionTest extends BufferTestSupport { public class BufferCompositionTest extends BufferTestSupport {
@Test @Test
public void compositeBufferCanOnlyBeOwnedWhenAllConstituentBuffersAreOwned() { public void compositeBufferCanOnlyBeOwnedWhenAllConstituentBuffersAreOwned() {
try (BufferAllocator allocator = BufferAllocator.heap()) { try (BufferAllocator allocator = BufferAllocator.heap()) {
@ -470,4 +469,244 @@ public class BufferCompositionTest extends BufferTestSupport {
} }
} }
} }
@Test
public void splitComponentsFloorMustThrowIfCompositeBufferIsNotOwned() {
try (BufferAllocator allocator = BufferAllocator.heap();
Buffer a = allocator.allocate(8);
Buffer b = allocator.allocate(8);
CompositeBuffer composite = CompositeBuffer.compose(allocator, a, b)) {
assertThrows(IllegalStateException.class, () -> composite.splitComponentsFloor(0));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsFloor(4));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsFloor(7));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsFloor(8));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsFloor(9));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsFloor(12));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsFloor(16));
}
}
@Test
public void splitComponentsCeilMustThrowIfCompositeBufferIsNotOwned() {
try (BufferAllocator allocator = BufferAllocator.heap();
Buffer a = allocator.allocate(8);
Buffer b = allocator.allocate(8);
CompositeBuffer composite = CompositeBuffer.compose(allocator, a, b)) {
assertThrows(IllegalStateException.class, () -> composite.splitComponentsCeil(0));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsCeil(4));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsCeil(7));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsCeil(8));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsCeil(9));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsCeil(12));
assertThrows(IllegalStateException.class, () -> composite.splitComponentsCeil(16));
}
}
@Test
public void splitComponentsFloorMustThrowOnOutOfBounds() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
assertThrows(IllegalArgumentException.class, () -> composite.splitComponentsFloor(-1));
assertThrows(IllegalArgumentException.class, () -> composite.splitComponentsFloor(17));
try (CompositeBuffer split = composite.splitComponentsFloor(16)) {
assertThat(split.capacity()).isEqualTo(16);
assertThat(composite.capacity()).isZero();
}
}
}
@Test
public void splitComponentsCeilMustThrowOnOutOfBounds() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
assertThrows(IllegalArgumentException.class, () -> composite.splitComponentsCeil(-1));
assertThrows(IllegalArgumentException.class, () -> composite.splitComponentsCeil(17));
try (CompositeBuffer split = composite.splitComponentsCeil(16)) {
assertThat(split.capacity()).isEqualTo(16);
assertThat(composite.capacity()).isZero();
}
}
}
@Test
public void splitComponentsFloorMustGiveEmptyBufferForOffsetInFirstComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsFloor(4)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isZero();
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(16);
}
}
}
@Test
public void splitComponentsFloorMustGiveEmptyBufferForOffsetLastByteInFirstComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsFloor(7)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isZero();
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(16);
}
}
}
@Test
public void splitComponentsFloorMustGiveBufferWithFirstComponentForOffsetInSecondComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsFloor(12)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isEqualTo(8);
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(8);
}
}
}
@Test
public void splitComponentsFloorMustGiveBufferWithFirstComponentForOffsetOnFirstByteInSecondComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsFloor(8)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isEqualTo(8);
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(8);
}
}
}
@Test
public void splitComponentsCeilMustGiveBufferWithFirstComponenForOffsetInFirstComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsCeil(4)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isEqualTo(8);
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(8);
}
}
}
@Test
public void splitComponentsCeilMustGiveBufferWithFirstComponentFofOffsetOnLastByteInFirstComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsCeil(7)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isEqualTo(8);
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(8);
}
}
}
@Test
public void splitComponentsCeilMustGiveBufferWithFirstAndSecondComponentForfOffsetInSecondComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsCeil(12)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isEqualTo(16);
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(0);
}
}
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsCeil(12)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isEqualTo(16);
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(8);
}
}
}
@Test
public void splitComponentsCeilMustGiveBufferWithFirstComponentForfOffsetOnFirstByteInSecondComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsCeil(7)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isEqualTo(8);
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(8);
}
}
}
@Test
public void splitComponentsCeilMustGiveEmptyBufferForOffsetOnFirstByteInFirstComponent() {
try (BufferAllocator allocator = BufferAllocator.heap();
CompositeBuffer composite = CompositeBuffer.compose(allocator,
allocator.allocate(8).send(),
allocator.allocate(8).send())) {
try (CompositeBuffer split = composite.splitComponentsCeil(0)) {
assertTrue(split.isOwned());
assertTrue(split.isAccessible());
assertThat(split.capacity()).isZero();
assertTrue(composite.isOwned());
assertTrue(composite.isAccessible());
assertThat(composite.capacity()).isEqualTo(16);
}
}
}
} }