org.apache.flink.state.api.output

Class MergeOperatorStates

java.lang.Object

org.apache.flink.state.api.output.MergeOperatorStates

All Implemented Interfaces:

Serializable, Function, GroupReduceFunction<OperatorState,CheckpointMetadata>

@Internal
public class MergeOperatorStates
extends Object
implements GroupReduceFunction<OperatorState,CheckpointMetadata>

A reducer that aggregates multiple OperatorState's into a single CheckpointMetadata.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
MergeOperatorStates(Collection<MasterState> masterStates)

Method Summary

Modifier and Type	Method and Description
void	reduce(Iterable<OperatorState> values, Collector<CheckpointMetadata> out) The reduce method.

Methods inherited from class java.lang.Object

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

Constructor Detail

MergeOperatorStates

public MergeOperatorStates(Collection<MasterState> masterStates)

Method Detail

reduce

public void reduce(Iterable<OperatorState> values,
                   Collector<CheckpointMetadata> out)

Description copied from interface: GroupReduceFunction

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

Specified by:

reduce in interface GroupReduceFunction<OperatorState,CheckpointMetadata>

Parameters:

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

out - The collector to hand results to.