com.google.cloud.dataflow.sdk.util.common.worker

Interface PartialGroupByKeyOperation.Combiner<K,InputT,AccumT,OutputT>

All Known Implementing Classes:

MapTaskExecutorFactory.ValueCombiner

Enclosing class:

PartialGroupByKeyOperation

public static interface PartialGroupByKeyOperation.Combiner<K,InputT,AccumT,OutputT>

Provides client-specific operations for combining values.

Method Summary

Modifier and Type	Method and Description
AccumT	add(K key, AccumT accumulator, InputT value)
AccumT	createAccumulator(K key)
OutputT	extract(K key, AccumT accumulator)
AccumT	merge(K key, Iterable<AccumT> accumulators)

Method Detail

createAccumulator

AccumT createAccumulator(K key)

add

AccumT add(K key,
           AccumT accumulator,
           InputT value)

merge

AccumT merge(K key,
             Iterable<AccumT> accumulators)

extract

OutputT extract(K key,
                AccumT accumulator)