本文整理了Java中com.facebook.presto.spi.block.Block.getRegion()方法的一些代码示例，展示了Block.getRegion()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。Block.getRegion()方法的具体详情如下：
包路径：com.facebook.presto.spi.block.Block
类名称：Block
方法名：getRegion
[英]Returns a block starting at the specified position and extends for the specified length. The specified region must be entirely contained within this block.
The region can be a view over this block. If this block is released the region block may also be released. If the region block is released this block may also be released.
[中]返回从指定位置开始并延伸指定长度的块。指定的区域必须完全包含在此块中。
该区域可以是该块上的视图。如果该块被释放，区域块也可能被释放。如果区域块被释放，该块也可能被释放。
代码示例来源：origin: prestodb/presto
@Override
public Block getRegion(int positionOffset, int length)
{
return block.getRegion(positionOffset, length);
}代码示例来源：origin: prestodb/presto
@Override
public Block getRegion(int positionOffset, int length)
{
assureLoaded();
return block.getRegion(positionOffset, length);
}代码示例来源：origin: prestodb/presto
public Page getRegion(int positionOffset, int length)
{
if (positionOffset < 0 || length < 0 || positionOffset + length > positionCount) {
throw new IndexOutOfBoundsException(format("Invalid position %s and length %s in page with %s positions", positionOffset, length, positionCount));
}
int channelCount = getChannelCount();
Block[] slicedBlocks = new Block[channelCount];
for (int i = 0; i < channelCount; i++) {
slicedBlocks[i] = blocks[i].getRegion(positionOffset, length);
}
return new Page(length, slicedBlocks);
}代码示例来源：origin: prestodb/presto
@Override
public <T> T getObject(int position, Class<T> clazz)
{
if (clazz != Block.class) {
throw new IllegalArgumentException("clazz must be Block.class");
}
checkReadablePosition(position);
int startValueOffset = getOffset(position);
int endValueOffset = getOffset(position + 1);
return clazz.cast(getRawElementBlock().getRegion(startValueOffset, endValueOffset - startValueOffset));
}代码示例来源：origin: prestodb/presto
public static RunLengthEncodedBlock createTestRleBlock(Block block, int position)
{
return new RunLengthEncodedBlock(block.getRegion(position, 1), 10);
}
}代码示例来源：origin: prestodb/presto
protected List<Block> splitBlock(Block block, int count)
{
double sizePerSplit = block.getPositionCount() * 1.0 / count;
ImmutableList.Builder<Block> result = ImmutableList.builder();
for (int i = 0; i < count; i++) {
int startPosition = toIntExact(Math.round(sizePerSplit * i));
int endPosition = toIntExact(Math.round(sizePerSplit * (i + 1)));
result.add(block.getRegion(startPosition, endPosition - startPosition));
}
return result.build();
}代码示例来源：origin: prestodb/presto
public static ColumnarMap toColumnarMap(Block block)
{
requireNonNull(block, "block is null");
if (block instanceof DictionaryBlock) {
return toColumnarMap((DictionaryBlock) block);
}
if (block instanceof RunLengthEncodedBlock) {
return toColumnarMap((RunLengthEncodedBlock) block);
}
if (!(block instanceof AbstractMapBlock)) {
throw new IllegalArgumentException("Invalid map block: " + block.getClass().getName());
}
AbstractMapBlock mapBlock = (AbstractMapBlock) block;
int offsetBase = mapBlock.getOffsetBase();
int[] offsets = mapBlock.getOffsets();
// get the keys and values for visible region
int firstEntryPosition = mapBlock.getOffset(0);
int totalEntryCount = mapBlock.getOffset(block.getPositionCount()) - firstEntryPosition;
Block keysBlock = mapBlock.getRawKeyBlock().getRegion(firstEntryPosition, totalEntryCount);
Block valuesBlock = mapBlock.getRawValueBlock().getRegion(firstEntryPosition, totalEntryCount);
return new ColumnarMap(block, offsetBase, offsets, keysBlock, valuesBlock);
}代码示例来源：origin: prestodb/presto
@Override
public void writeBlock(BlockEncodingSerde blockEncodingSerde, SliceOutput sliceOutput, Block block)
{
SingleRowBlock singleRowBlock = (SingleRowBlock) block;
int numFields = singleRowBlock.getNumFields();
int rowIndex = singleRowBlock.getRowIndex();
sliceOutput.appendInt(numFields);
for (int i = 0; i < numFields; i++) {
blockEncodingSerde.writeBlock(sliceOutput, singleRowBlock.getRawFieldBlock(i).getRegion(rowIndex, 1));
}
}代码示例来源：origin: prestodb/presto
@Override
public Work<Block> project(ConnectorSession session, DriverYieldSignal yieldSignal, Page page, SelectedPositions selectedPositions)
{
Block block = requireNonNull(page, "page is null").getBlock(0);
requireNonNull(selectedPositions, "selectedPositions is null");
Block result;
if (selectedPositions.isList()) {
result = block.copyPositions(selectedPositions.getPositions(), selectedPositions.getOffset(), selectedPositions.size());
}
else {
result = block.getRegion(selectedPositions.getOffset(), selectedPositions.size());
}
return new CompletedWork<>(result);
}
}代码示例来源：origin: prestodb/presto
@Override
public void writeBlock(BlockEncodingSerde blockEncodingSerde, SliceOutput sliceOutput, Block block)
{
SingleMapBlock singleMapBlock = (SingleMapBlock) block;
TypeSerde.writeType(sliceOutput, singleMapBlock.keyType);
int offset = singleMapBlock.getOffset();
int positionCount = singleMapBlock.getPositionCount();
blockEncodingSerde.writeBlock(sliceOutput, singleMapBlock.getRawKeyBlock().getRegion(offset / 2, positionCount / 2));
blockEncodingSerde.writeBlock(sliceOutput, singleMapBlock.getRawValueBlock().getRegion(offset / 2, positionCount / 2));
int[] hashTable = singleMapBlock.getHashTable();
sliceOutput.appendInt(positionCount / 2 * HASH_MULTIPLIER);
sliceOutput.writeBytes(wrappedIntArray(hashTable, offset / 2 * HASH_MULTIPLIER, positionCount / 2 * HASH_MULTIPLIER));
}代码示例来源：origin: prestodb/presto
@Override
public void addInput(Page page)
{
checkState(needsInput());
if (page.getPositionCount() <= remainingLimit) {
remainingLimit -= page.getPositionCount();
nextPage = page;
}
else {
Block[] blocks = new Block[page.getChannelCount()];
for (int channel = 0; channel < page.getChannelCount(); channel++) {
Block block = page.getBlock(channel);
blocks[channel] = block.getRegion(0, (int) remainingLimit);
}
nextPage = new Page((int) remainingLimit, blocks);
remainingLimit = 0;
}
}代码示例来源：origin: prestodb/presto
@Override
public void writeBlock(BlockEncodingSerde blockEncodingSerde, SliceOutput sliceOutput, Block block)
{
AbstractArrayBlock arrayBlock = (AbstractArrayBlock) block;
int positionCount = arrayBlock.getPositionCount();
int offsetBase = arrayBlock.getOffsetBase();
int[] offsets = arrayBlock.getOffsets();
int valuesStartOffset = offsets[offsetBase];
int valuesEndOffset = offsets[offsetBase + positionCount];
Block values = arrayBlock.getRawElementBlock().getRegion(valuesStartOffset, valuesEndOffset - valuesStartOffset);
blockEncodingSerde.writeBlock(sliceOutput, values);
sliceOutput.appendInt(positionCount);
for (int position = 0; position < positionCount + 1; position++) {
sliceOutput.writeInt(offsets[offsetBase + position] - valuesStartOffset);
}
encodeNullsAsBits(sliceOutput, block);
}代码示例来源：origin: prestodb/presto
@Override
public void writeBlock(BlockEncodingSerde blockEncodingSerde, SliceOutput sliceOutput, Block block)
{
AbstractMapBlock mapBlock = (AbstractMapBlock) block;
int positionCount = mapBlock.getPositionCount();
int offsetBase = mapBlock.getOffsetBase();
int[] offsets = mapBlock.getOffsets();
int[] hashTable = mapBlock.getHashTables();
int entriesStartOffset = offsets[offsetBase];
int entriesEndOffset = offsets[offsetBase + positionCount];
TypeSerde.writeType(sliceOutput, mapBlock.keyType);
blockEncodingSerde.writeBlock(sliceOutput, mapBlock.getRawKeyBlock().getRegion(entriesStartOffset, entriesEndOffset - entriesStartOffset));
blockEncodingSerde.writeBlock(sliceOutput, mapBlock.getRawValueBlock().getRegion(entriesStartOffset, entriesEndOffset - entriesStartOffset));
sliceOutput.appendInt((entriesEndOffset - entriesStartOffset) * HASH_MULTIPLIER);
sliceOutput.writeBytes(wrappedIntArray(hashTable, entriesStartOffset * HASH_MULTIPLIER, (entriesEndOffset - entriesStartOffset) * HASH_MULTIPLIER));
sliceOutput.appendInt(positionCount);
for (int position = 0; position < positionCount + 1; position++) {
sliceOutput.writeInt(offsets[offsetBase + position] - entriesStartOffset);
}
EncoderUtil.encodeNullsAsBits(sliceOutput, block);
}代码示例来源：origin: prestodb/presto
protected void assertPositionEquals(Block block, int position, Object expectedStackValue, Object expectedObjectValue)
{
long hash = 0;
if (type.isComparable()) {
hash = hashPosition(type, block, position);
}
assertPositionValue(block, position, expectedStackValue, hash, expectedObjectValue);
assertPositionValue(block.getSingleValueBlock(position), 0, expectedStackValue, hash, expectedObjectValue);
assertPositionValue(block.getRegion(position, 1), 0, expectedStackValue, hash, expectedObjectValue);
assertPositionValue(block.getRegion(0, position + 1), position, expectedStackValue, hash, expectedObjectValue);
assertPositionValue(block.getRegion(position, block.getPositionCount() - position), 0, expectedStackValue, hash, expectedObjectValue);
BlockBuilder blockBuilder = type.createBlockBuilder(null, 1);
type.appendTo(block, position, blockBuilder);
assertPositionValue(blockBuilder.build(), 0, expectedStackValue, hash, expectedObjectValue);
}代码示例来源：origin: prestodb/presto
@Override
public void writeBlock(BlockEncodingSerde blockEncodingSerde, SliceOutput sliceOutput, Block block)
{
AbstractRowBlock rowBlock = (AbstractRowBlock) block;
int numFields = rowBlock.numFields;
int positionCount = rowBlock.getPositionCount();
int offsetBase = rowBlock.getOffsetBase();
int[] fieldBlockOffsets = rowBlock.getFieldBlockOffsets();
int startFieldBlockOffset = fieldBlockOffsets[offsetBase];
int endFieldBlockOffset = fieldBlockOffsets[offsetBase + positionCount];
sliceOutput.appendInt(numFields);
for (int i = 0; i < numFields; i++) {
blockEncodingSerde.writeBlock(sliceOutput, rowBlock.getRawFieldBlocks()[i].getRegion(startFieldBlockOffset, endFieldBlockOffset - startFieldBlockOffset));
}
sliceOutput.appendInt(positionCount);
for (int position = 0; position < positionCount + 1; position++) {
sliceOutput.writeInt(fieldBlockOffsets[offsetBase + position] - startFieldBlockOffset);
}
EncoderUtil.encodeNullsAsBits(sliceOutput, block);
}代码示例来源：origin: prestodb/presto
private static void verifyBlock(Block block, Slice[][][] expectedValues)
{
assertBlock(block, expectedValues);
assertColumnarMap(block, expectedValues);
assertDictionaryBlock(block, expectedValues);
assertRunLengthEncodedBlock(block, expectedValues);
int offset = 1;
int length = expectedValues.length - 2;
Block blockRegion = block.getRegion(offset, length);
Slice[][][] expectedValuesRegion = Arrays.copyOfRange(expectedValues, offset, offset + length);
assertBlock(blockRegion, expectedValuesRegion);
assertColumnarMap(blockRegion, expectedValuesRegion);
assertDictionaryBlock(blockRegion, expectedValuesRegion);
assertRunLengthEncodedBlock(blockRegion, expectedValuesRegion);
}代码示例来源：origin: prestodb/presto
private static <T> void verifyBlock(Block block, T[] expectedValues)
{
assertBlock(block, expectedValues);
assertColumnarArray(block, expectedValues);
assertDictionaryBlock(block, expectedValues);
assertRunLengthEncodedBlock(block, expectedValues);
int offset = 1;
int length = expectedValues.length - 2;
Block blockRegion = block.getRegion(offset, length);
T[] expectedValuesRegion = Arrays.copyOfRange(expectedValues, offset, offset + length);
assertBlock(blockRegion, expectedValuesRegion);
assertColumnarArray(blockRegion, expectedValuesRegion);
assertDictionaryBlock(blockRegion, expectedValuesRegion);
assertRunLengthEncodedBlock(blockRegion, expectedValuesRegion);
}代码示例来源：origin: prestodb/presto
private static <T> void verifyBlock(Block block, T[] expectedValues)
{
assertBlock(block, expectedValues);
assertColumnarRow(block, expectedValues);
assertDictionaryBlock(block, expectedValues);
assertRunLengthEncodedBlock(block, expectedValues);
int offset = 1;
int length = expectedValues.length - 2;
Block blockRegion = block.getRegion(offset, length);
T[] expectedValuesRegion = Arrays.copyOfRange(expectedValues, offset, offset + length);
assertBlock(blockRegion, expectedValuesRegion);
assertColumnarRow(blockRegion, expectedValuesRegion);
assertDictionaryBlock(blockRegion, expectedValuesRegion);
assertRunLengthEncodedBlock(blockRegion, expectedValuesRegion);
}代码示例来源：origin: prestodb/presto
private static void testProjectRange(Block block, Class<? extends Block> expectedResultType, DictionaryAwarePageProjection projection, boolean forceYield)
{
DriverYieldSignal yieldSignal = new DriverYieldSignal();
Work<Block> work = projection.project(null, yieldSignal, new Page(block), SelectedPositions.positionsRange(5, 10));
Block result;
if (forceYield) {
result = projectWithYield(work, yieldSignal);
}
else {
assertTrue(work.process());
result = work.getResult();
}
assertBlockEquals(
BIGINT,
result,
block.getRegion(5, 10));
assertInstanceOf(result, expectedResultType);
}代码示例来源：origin: prestodb/presto
private static void testProjectFastReturnIgnoreYield(Block block, DictionaryAwarePageProjection projection)
{
DriverYieldSignal yieldSignal = new DriverYieldSignal();
Work<Block> work = projection.project(null, yieldSignal, new Page(block), SelectedPositions.positionsRange(5, 10));
yieldSignal.setWithDelay(1, executor);
yieldSignal.forceYieldForTesting();
// yield signal is ignored given the block has already been loaded
assertTrue(work.process());
Block result = work.getResult();
yieldSignal.reset();
assertBlockEquals(
BIGINT,
result,
block.getRegion(5, 10));
assertInstanceOf(result, DictionaryBlock.class);
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