org.apache.flink.streaming.api.functions.windowing

Class ReduceApplyWindowFunction<K,W extends Window,T,R>

java.lang.Object

org.apache.flink.api.common.functions.AbstractRichFunction

org.apache.flink.api.java.operators.translation.WrappingFunction<WindowFunction<T,R,K,W>>

org.apache.flink.streaming.api.functions.windowing.ReduceApplyWindowFunction<K,W,T,R>

All Implemented Interfaces:

Serializable, Function, RichFunction, WindowFunction<T,R,K,W>

@Internal
public class ReduceApplyWindowFunction<K,W extends Window,T,R>
extends WrappingFunction<WindowFunction<T,R,K,W>>
implements WindowFunction<T,R,K,W>

Internal WindowFunction that is used for implementing a fold on a window configuration that only allows WindowFunction and cannot directly execute a ReduceFunction.

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.flink.api.java.operators.translation.WrappingFunction

wrappedFunction

Constructor Summary

Constructors

Constructor and Description
ReduceApplyWindowFunction(ReduceFunction<T> reduceFunction, WindowFunction<T,R,K,W> windowFunction)

Method Summary

Modifier and Type	Method and Description
void	apply(K k, W window, Iterable<T> input, Collector<R> out) Evaluates the window and outputs none or several elements.

Methods inherited from class org.apache.flink.api.java.operators.translation.WrappingFunction

close, getWrappedFunction, open, setRuntimeContext

Methods inherited from class org.apache.flink.api.common.functions.AbstractRichFunction

getIterationRuntimeContext, getRuntimeContext, open

Methods inherited from class java.lang.Object

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

Constructor Detail

ReduceApplyWindowFunction

public ReduceApplyWindowFunction(ReduceFunction<T> reduceFunction,
                                 WindowFunction<T,R,K,W> windowFunction)

Method Detail

apply

public void apply(K k,
                  W window,
                  Iterable<T> input,
                  Collector<R> out)
           throws Exception

Description copied from interface: WindowFunction

Evaluates the window and outputs none or several elements.

Specified by:

apply in interface WindowFunction<T,R,K,W extends Window>

Parameters:

k - The key for which this window is evaluated.

window - The window that is being evaluated.

input - The elements in the window being evaluated.

out - A collector for emitting elements.

Throws:

Exception - The function may throw exceptions to fail the program and trigger recovery.