org.apache.flink.streaming.runtime.operators.windowing.buffers

Class FoldingWindowBuffer<T,ACC>

java.lang.Object

org.apache.flink.streaming.runtime.operators.windowing.buffers.FoldingWindowBuffer<T,ACC>

Type Parameters:

T - The type of elements that can be added to this WindowBuffer.

ACC - The type of the accumulator that this WindowBuffer can store.

All Implemented Interfaces:

WindowBuffer<T,ACC>

@Internal
public class FoldingWindowBuffer<T,ACC>
extends Object
implements WindowBuffer<T,ACC>

An WindowBuffer that stores elements on the Java Heap. This buffer uses a FoldFunction to incrementally aggregate elements that are added to the buffer.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FoldingWindowBuffer.Factory<T,ACC>

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FoldingWindowBuffer(org.apache.flink.api.common.functions.FoldFunction<T,ACC> foldFunction, ACC initialAccumulator, org.apache.flink.api.common.typeutils.TypeSerializer<ACC> accSerializer)
protected	FoldingWindowBuffer(org.apache.flink.api.common.functions.FoldFunction<T,ACC> foldFunction, StreamRecord<ACC> initialAccumulator, org.apache.flink.api.common.typeutils.TypeSerializer<ACC> accSerializer)

Method Summary

Modifier and Type	Method and Description
Iterable<StreamRecord<ACC>>	getElements() Returns all elements that are currently in the buffer.
Iterable<ACC>	getUnpackedElements() Returns all elements that are currently in the buffer.
int	size() Returns the number of elements that are currently in the buffer.
void	snapshot(org.apache.flink.core.memory.DataOutputView out) Writes the contents of the window buffer to a DataOutputView for checkpointing.
void	storeElement(StreamRecord<T> element) Adds the element to the buffer.

Methods inherited from class java.lang.Object

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

Constructor Detail

FoldingWindowBuffer

protected FoldingWindowBuffer(org.apache.flink.api.common.functions.FoldFunction<T,ACC> foldFunction,
                              ACC initialAccumulator,
                              org.apache.flink.api.common.typeutils.TypeSerializer<ACC> accSerializer)

FoldingWindowBuffer

protected FoldingWindowBuffer(org.apache.flink.api.common.functions.FoldFunction<T,ACC> foldFunction,
                              StreamRecord<ACC> initialAccumulator,
                              org.apache.flink.api.common.typeutils.TypeSerializer<ACC> accSerializer)

Method Detail

storeElement

public void storeElement(StreamRecord<T> element)
                  throws Exception

Description copied from interface: WindowBuffer

Adds the element to the buffer.

Specified by:

storeElement in interface WindowBuffer<T,ACC>

Parameters:

element - The element to add.

Throws:

Exception

getElements

public Iterable<StreamRecord<ACC>> getElements()

Description copied from interface: WindowBuffer

Returns all elements that are currently in the buffer.

Specified by:

getElements in interface WindowBuffer<T,ACC>

getUnpackedElements

public Iterable<ACC> getUnpackedElements()

Description copied from interface: WindowBuffer

Returns all elements that are currently in the buffer. This will unwrap the contained elements from their StreamRecord.

Specified by:

getUnpackedElements in interface WindowBuffer<T,ACC>

size

public int size()

Description copied from interface: WindowBuffer

Returns the number of elements that are currently in the buffer.

Specified by:

size in interface WindowBuffer<T,ACC>

snapshot

public void snapshot(org.apache.flink.core.memory.DataOutputView out)
              throws IOException

Description copied from interface: WindowBuffer

Writes the contents of the window buffer to a DataOutputView for checkpointing.

Specified by:

snapshot in interface WindowBuffer<T,ACC>

Throws:

IOException