org.apache.flink.runtime.operators.hash

Class InPlaceMutableHashTable.ReduceFacade

java.lang.Object

org.apache.flink.runtime.operators.hash.InPlaceMutableHashTable.ReduceFacade

Enclosing class:

InPlaceMutableHashTable<T>

public final class InPlaceMutableHashTable.ReduceFacade
extends Object

A facade for doing such operations on the hash table that are needed for a reduce operator driver.

Constructor Summary

Constructors

Constructor and Description
InPlaceMutableHashTable.ReduceFacade(ReduceFunction<T> reducer, Collector<T> outputCollector, boolean objectReuseEnabled)

Method Summary

Methods

Modifier and Type	Method and Description
void	emit() Emits all elements currently held by the table to the collector.
void	emitAndReset() Emits all elements currently held by the table to the collector, and resets the table.
void	updateTableEntryWithReduce(T record) Looks up the table entry that has the same key as the given record, and updates it by performing a reduce step.

Methods inherited from class java.lang.Object

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

Constructor Detail

InPlaceMutableHashTable.ReduceFacade

public InPlaceMutableHashTable.ReduceFacade(ReduceFunction<T> reducer,
                                    Collector<T> outputCollector,
                                    boolean objectReuseEnabled)

Method Detail

updateTableEntryWithReduce

public void updateTableEntryWithReduce(T record)
                                throws Exception

Looks up the table entry that has the same key as the given record, and updates it by performing a reduce step.

Parameters:

record - The record to update.

Throws:

Exception

emit

public void emit()
          throws IOException

Emits all elements currently held by the table to the collector.

Throws:

IOException

emitAndReset

public void emitAndReset()
                  throws IOException

Emits all elements currently held by the table to the collector, and resets the table. The table will have the same number of buckets as before the reset, to avoid doing resizes again.

Throws:

IOException