org.apache.flink.runtime.io.network.buffer

类 FileRegionBuffer

java.lang.Object

org.apache.flink.shaded.netty4.io.netty.util.AbstractReferenceCounted

org.apache.flink.shaded.netty4.io.netty.channel.DefaultFileRegion

org.apache.flink.runtime.io.network.buffer.FileRegionBuffer

所有已实现的接口:

Buffer, org.apache.flink.shaded.netty4.io.netty.channel.FileRegion, org.apache.flink.shaded.netty4.io.netty.util.ReferenceCounted

public class FileRegionBuffer
extends org.apache.flink.shaded.netty4.io.netty.channel.DefaultFileRegion
implements Buffer

This class represents a chunk of data in a file channel. Its purpose is to be passed to the netty code and to be written to the socket via the zero-copy direct transfer capabilities of FileChannel.transferTo(long, long, WritableByteChannel).

This class implements Buffer mainly for compatible with existing usages. It can be thought of as a "lazy buffer" that does not hold the data directly, although the data can be fetches as a read-only ByteBuffer when needed, for example in local input channels. See readInto(MemorySegment) and getNioBufferReadable(). Because this buffer is read-only, the modification methods (and methods that give a writable buffer) throw UnsupportedOperationException.

This class extends from Netty's DefaultFileRegion, similar as the NetworkBuffer extends from Netty's ByteBuf. That way we can pass both of them to Netty in the same way, and Netty will internally treat them appropriately.

嵌套类概要

从接口继承的嵌套类/接口 org.apache.flink.runtime.io.network.buffer.Buffer

Buffer.DataType

构造器概要

构造器

构造器和说明
FileRegionBuffer(FileChannel fileChannel, long fileChannelPosition, int bufferSize, Buffer.DataType dataType, boolean isCompressed)

方法概要

限定符和类型	方法和说明
org.apache.flink.shaded.netty4.io.netty.buffer.ByteBuf	asByteBuf()
void	deallocate()
Buffer.DataType	getDataType() Gets the type of data this buffer represents.
int	getMaxCapacity() Returns the maximum size of the buffer, i.e. the capacity of the underlying MemorySegment.
org.apache.flink.core.memory.MemorySegment	getMemorySegment() Returns the underlying memory segment.
int	getMemorySegmentOffset() This method will be removed in the future.
ByteBuffer	getNioBuffer(int index, int length) Gets a new ByteBuffer instance wrapping this buffer's bytes.
ByteBuffer	getNioBufferReadable() This method is only called by tests and by event-deserialization, like checkpoint barriers.
int	getReaderIndex() Returns the reader index of this buffer.
BufferRecycler	getRecycler() Gets the buffer's recycler.
int	getSize() Returns the size of the written data, i.e. the writer index, of this buffer.
boolean	isBuffer() Returns whether this buffer represents a buffer or an event.
boolean	isCompressed()
boolean	isRecycled() Returns whether this buffer has been recycled or not.
int	readableBytes() Returns the number of readable bytes (same as Buffer.getSize() - Buffer.getReaderIndex()).
Buffer	readInto(org.apache.flink.core.memory.MemorySegment segment)
ReadOnlySlicedNetworkBuffer	readOnlySlice() Returns a read-only slice of this buffer's readable bytes, i.e. between Buffer.getReaderIndex() and Buffer.getSize().
ReadOnlySlicedNetworkBuffer	readOnlySlice(int index, int length) Returns a read-only slice of this buffer.
void	recycleBuffer() Releases this buffer once, i.e. reduces the reference count and recycles the buffer if the reference count reaches 0.
FileRegionBuffer	retainBuffer() Retains this buffer for further use, increasing the reference counter by 1.
void	setAllocator(org.apache.flink.shaded.netty4.io.netty.buffer.ByteBufAllocator allocator) Sets the buffer allocator for use in netty.
void	setCompressed(boolean isCompressed) Tags the buffer as compressed or uncompressed.
void	setDataType(Buffer.DataType dataType) Sets the type of data this buffer represents.
void	setReaderIndex(int readerIndex) Sets the reader index of this buffer.
void	setSize(int writerIndex) Sets the size of the written data, i.e. the writer index, of this buffer.

从类继承的方法 org.apache.flink.shaded.netty4.io.netty.channel.DefaultFileRegion

count, isOpen, open, position, retain, retain, touch, touch, transfered, transferred, transferTo

从类继承的方法 org.apache.flink.shaded.netty4.io.netty.util.AbstractReferenceCounted

refCnt, release, release, setRefCnt

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

从接口继承的方法 org.apache.flink.runtime.io.network.buffer.Buffer

refCnt, toDebugString

从接口继承的方法 org.apache.flink.shaded.netty4.io.netty.util.ReferenceCounted

refCnt, release, release

构造器详细资料

FileRegionBuffer

public FileRegionBuffer(FileChannel fileChannel,
                        long fileChannelPosition,
                        int bufferSize,
                        Buffer.DataType dataType,
                        boolean isCompressed)

方法详细资料

isBuffer

public boolean isBuffer()

从接口复制的说明: Buffer

Returns whether this buffer represents a buffer or an event.

指定者:

isBuffer 在接口中 Buffer

返回:

true if this is a real buffer, false if this is an event

getMemorySegment

public org.apache.flink.core.memory.MemorySegment getMemorySegment()

从接口复制的说明: Buffer

Returns the underlying memory segment. This method is dangerous since it ignores read only protections and omits slices. Use it only along the Buffer.getMemorySegmentOffset().

This method will be removed in the future. For writing use BufferBuilder.

指定者:

getMemorySegment 在接口中 Buffer

返回:

the memory segment backing this buffer

getMemorySegmentOffset

public int getMemorySegmentOffset()

从接口复制的说明: Buffer

This method will be removed in the future. For writing use BufferBuilder.

指定者:

getMemorySegmentOffset 在接口中 Buffer

返回:

the offset where this (potential slice) Buffer's data start in the underlying memory segment.

readOnlySlice

public ReadOnlySlicedNetworkBuffer readOnlySlice()

从接口复制的说明: Buffer

Returns a read-only slice of this buffer's readable bytes, i.e. between Buffer.getReaderIndex() and Buffer.getSize().

Reader and writer indices as well as markers are not shared. Reference counters are shared but the slice is not retained automatically.

指定者:

readOnlySlice 在接口中 Buffer

返回:

a read-only sliced buffer

readOnlySlice

public ReadOnlySlicedNetworkBuffer readOnlySlice(int index,
                                                 int length)

从接口复制的说明: Buffer

Returns a read-only slice of this buffer.

Reader and writer indices as well as markers are not shared. Reference counters are shared but the slice is not retained automatically.

指定者:

readOnlySlice 在接口中 Buffer

参数:

index - the index to start from

length - the length of the slice

返回:

a read-only sliced buffer

getMaxCapacity

public int getMaxCapacity()

从接口复制的说明: Buffer

Returns the maximum size of the buffer, i.e. the capacity of the underlying MemorySegment.

指定者:

getMaxCapacity 在接口中 Buffer

返回:

size of the buffer

getReaderIndex

public int getReaderIndex()

从接口复制的说明: Buffer

Returns the reader index of this buffer.

This is where readable (unconsumed) bytes start in the backing memory segment.

指定者:

getReaderIndex 在接口中 Buffer

返回:

reader index (from 0 (inclusive) to the size of the backing MemorySegment (inclusive))

setReaderIndex

public void setReaderIndex(int readerIndex)
                    throws IndexOutOfBoundsException

从接口复制的说明: Buffer

Sets the reader index of this buffer.

指定者:

setReaderIndex 在接口中 Buffer

抛出:

IndexOutOfBoundsException - if the index is less than 0 or greater than Buffer.getSize()

getNioBufferReadable

public ByteBuffer getNioBufferReadable()

This method is only called by tests and by event-deserialization, like checkpoint barriers. Because such events are not used for bounded intermediate results, this method currently executes only in tests.

指定者:

getNioBufferReadable 在接口中 Buffer

返回:

byte buffer sharing the contents of the underlying memory segment

getNioBuffer

public ByteBuffer getNioBuffer(int index,
                               int length)
                        throws IndexOutOfBoundsException

从接口复制的说明: Buffer

Gets a new ByteBuffer instance wrapping this buffer's bytes.

Please note that neither read nor write index are updated by the returned buffer.

指定者:

getNioBuffer 在接口中 Buffer

返回:

byte buffer sharing the contents of the underlying memory segment

抛出:

IndexOutOfBoundsException - if the indexes are not without the buffer's bounds

另请参阅:

Buffer.getNioBufferReadable()

asByteBuf

public org.apache.flink.shaded.netty4.io.netty.buffer.ByteBuf asByteBuf()

指定者:

asByteBuf 在接口中 Buffer

返回:

self as ByteBuf implementation.

setSize

public void setSize(int writerIndex)

从接口复制的说明: Buffer

Sets the size of the written data, i.e. the writer index, of this buffer.

指定者:

setSize 在接口中 Buffer

getSize

public int getSize()

从接口复制的说明: Buffer

Returns the size of the written data, i.e. the writer index, of this buffer.

This is where writable bytes start in the backing memory segment.

指定者:

getSize 在接口中 Buffer

返回:

writer index (from 0 (inclusive) to the size of the backing MemorySegment (inclusive))

readableBytes

public int readableBytes()

从接口复制的说明: Buffer

Returns the number of readable bytes (same as Buffer.getSize() - Buffer.getReaderIndex()).

指定者:

readableBytes 在接口中 Buffer

setAllocator

public void setAllocator(org.apache.flink.shaded.netty4.io.netty.buffer.ByteBufAllocator allocator)

从接口复制的说明: Buffer

Sets the buffer allocator for use in netty.

指定者:

setAllocator 在接口中 Buffer

参数:

allocator - netty buffer allocator

getRecycler

public BufferRecycler getRecycler()

从接口复制的说明: Buffer

Gets the buffer's recycler.

指定者:

getRecycler 在接口中 Buffer

返回:

buffer recycler

recycleBuffer

public void recycleBuffer()

从接口复制的说明: Buffer

Releases this buffer once, i.e. reduces the reference count and recycles the buffer if the reference count reaches 0.

指定者:

recycleBuffer 在接口中 Buffer

另请参阅:

Buffer.retainBuffer()

isRecycled

public boolean isRecycled()

从接口复制的说明: Buffer

Returns whether this buffer has been recycled or not.

指定者:

isRecycled 在接口中 Buffer

返回:

true if already recycled, false otherwise

retainBuffer

public FileRegionBuffer retainBuffer()

从接口复制的说明: Buffer

Retains this buffer for further use, increasing the reference counter by 1.

指定者:

retainBuffer 在接口中 Buffer

返回:

this instance (for chained calls)

另请参阅:

Buffer.recycleBuffer()

isCompressed

public boolean isCompressed()

指定者:

isCompressed 在接口中 Buffer

返回:

whether the buffer is compressed or not.

setCompressed

public void setCompressed(boolean isCompressed)

从接口复制的说明: Buffer

Tags the buffer as compressed or uncompressed.

指定者:

setCompressed 在接口中 Buffer

getDataType

public Buffer.DataType getDataType()

从接口复制的说明: Buffer

Gets the type of data this buffer represents.

指定者:

getDataType 在接口中 Buffer

setDataType

public void setDataType(Buffer.DataType dataType)

从接口复制的说明: Buffer

Sets the type of data this buffer represents.

指定者:

setDataType 在接口中 Buffer

deallocate

public void deallocate()

覆盖:

deallocate 在类中 org.apache.flink.shaded.netty4.io.netty.channel.DefaultFileRegion

readInto

public Buffer readInto(org.apache.flink.core.memory.MemorySegment segment)
                throws IOException

抛出:

IOException