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

Class BufferConsumer

java.lang.Object

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

All Implemented Interfaces:

Closeable, AutoCloseable

@NotThreadSafe
public class BufferConsumer
extends Object
implements Closeable

Not thread safe class for producing Buffer.

It reads data written by BufferBuilder. Although it is not thread safe and can be used only by one single thread, this thread can be different than the thread using/writing to BufferBuilder. Pattern here is simple: one thread writes data to BufferBuilder and there can be a different thread reading from it using BufferConsumer.

Constructor Summary

Constructors

Constructor and Description
BufferConsumer(Buffer buffer, org.apache.flink.runtime.io.network.buffer.BufferBuilder.PositionMarker currentWriterPosition, int currentReaderPosition)
BufferConsumer(Buffer buffer, int size) Constructs BufferConsumer instance with static content of a certain size.

Method Summary

Modifier and Type	Method and Description
Buffer	build()
void	close()
BufferConsumer	copy() Returns a retained copy with separate indexes.
BufferConsumer	copyWithReaderPosition(int readerPosition) Returns a retained copy with separate indexes and sets the reader position to the given value.
Buffer.DataType	getDataType()
int	getWrittenBytes()
boolean	isBuffer()
boolean	isDataAvailable() Returns true if there is new data available for reading.
boolean	isFinished() Checks whether the BufferBuilder has already been finished.
boolean	isRecycled()
String	toDebugString(boolean includeHash)

Methods inherited from class java.lang.Object

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

Constructor Detail

BufferConsumer

public BufferConsumer(Buffer buffer,
                      int size)

Constructs BufferConsumer instance with static content of a certain size.

BufferConsumer

public BufferConsumer(Buffer buffer,
                      org.apache.flink.runtime.io.network.buffer.BufferBuilder.PositionMarker currentWriterPosition,
                      int currentReaderPosition)

Method Detail

isFinished

public boolean isFinished()

Checks whether the BufferBuilder has already been finished.

BEWARE: this method accesses the cached value of the position marker which is only updated after calls to build() and skip(int)!

Returns:

true if the buffer was finished, false otherwise

build

public Buffer build()

Returns:

sliced Buffer containing the not yet consumed data. Returned Buffer shares the reference counter with the parent BufferConsumer - in order to recycle memory both of them must be recycled/closed.

copy

public BufferConsumer copy()

Returns a retained copy with separate indexes. This allows to read from the same MemorySegment twice.

WARNING: the newly returned BufferConsumer will have its reader index copied from the original buffer. In other words, data already consumed before copying will not be visible to the returned copies.

Returns:

a retained copy of self with separate indexes

copyWithReaderPosition

public BufferConsumer copyWithReaderPosition(int readerPosition)

Returns a retained copy with separate indexes and sets the reader position to the given value. This allows to read from the same MemorySegment twice starting from the supplied position.

Parameters:

readerPosition - the new reader position. Can be less than the currentReaderPosition, but may not exceed the current writer's position.

Returns:

a retained copy of self with separate indexes

isBuffer

public boolean isBuffer()

getDataType

public Buffer.DataType getDataType()

close

public void close()

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

isRecycled

public boolean isRecycled()

getWrittenBytes

public int getWrittenBytes()

isDataAvailable

public boolean isDataAvailable()

Returns true if there is new data available for reading.

toDebugString

public String toDebugString(boolean includeHash)