org.apache.flink.api.java.operators.translation

Class CombineToGroupCombineWrapper<IN,OUT,F extends CombineFunction<IN,IN> & GroupReduceFunction<IN,OUT>>

java.lang.Object

org.apache.flink.api.java.operators.translation.CombineToGroupCombineWrapper<IN,OUT,F>

All Implemented Interfaces:

Serializable, Function, GroupCombineFunction<IN,IN>, GroupReduceFunction<IN,OUT>

@Internal
public class CombineToGroupCombineWrapper<IN,OUT,F extends CombineFunction<IN,IN> & GroupReduceFunction<IN,OUT>>
extends Object
implements GroupCombineFunction<IN,IN>, GroupReduceFunction<IN,OUT>

A wrapper the wraps a function that implements both CombineFunction and GroupReduceFunction interfaces and makes it look like a function that implements GroupCombineFunction and GroupReduceFunction to the runtime.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
CombineToGroupCombineWrapper(F wrappedFunction)

Method Summary

Modifier and Type	Method and Description
void	combine(Iterable<IN> values, Collector<IN> out) The combine method, called (potentially multiple timed) with subgroups of elements.
void	reduce(Iterable<IN> values, Collector<OUT> out) The reduce method.

Methods inherited from class java.lang.Object

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

Constructor Detail

CombineToGroupCombineWrapper

public CombineToGroupCombineWrapper(F wrappedFunction)

Method Detail

combine

public void combine(Iterable<IN> values,
                    Collector<IN> out)
             throws Exception

Description copied from interface: GroupCombineFunction

The combine method, called (potentially multiple timed) with subgroups of elements.

Specified by:

combine in interface GroupCombineFunction<IN,IN>

Parameters:

values - The elements to be combined.

out - The collector to use to return values from the function.

Throws:

Exception - The function may throw Exceptions, which will cause the program to cancel, and may trigger the recovery logic.

reduce

public void reduce(Iterable<IN> values,
                   Collector<OUT> out)
            throws Exception

Description copied from interface: GroupReduceFunction

The reduce method. The function receives one call per group of elements.

Specified by:

reduce in interface GroupReduceFunction<IN,OUT>

Parameters:

values - All records that belong to the given input key.

out - The collector to hand results to.

Throws:

Exception - This method may throw exceptions. Throwing an exception will cause the operation to fail and may trigger recovery.