Package org.apache.spark

Class Aggregator<K,V,C>

Object

org.apache.spark.Aggregator<K,V,C>

All Implemented Interfaces:

Serializable, scala.Equals, scala.Product

public class Aggregator<K,V,C>
extends Object
implements scala.Product, Serializable

:: DeveloperApi :: A set of functions used to aggregate data.

param: createCombiner function to create the initial value of the aggregation. param: mergeValue function to merge a new value into the aggregation result. param: mergeCombiners function to merge outputs from multiple mergeValue function.

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
Aggregator(scala.Function1<V,C> createCombiner, scala.Function2<C,V,C> mergeValue, scala.Function2<C,C,C> mergeCombiners)

Method Summary

Modifier and Type	Method	Description
scala.collection.Iterator<scala.Tuple2<K,C>>	combineCombinersByKey(scala.collection.Iterator<scala.Product2<K,C>> iter, TaskContext context)
scala.collection.Iterator<scala.Tuple2<K,C>>	combineValuesByKey(scala.collection.Iterator<scala.Product2<K,V>> iter, TaskContext context)
scala.Function1<V,C>	createCombiner()
scala.Function2<C,C,C>	mergeCombiners()
scala.Function2<C,V,C>	mergeValue()

Methods inherited from class java.lang.Object

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

Methods inherited from interface scala.Equals

canEqual, equals

Methods inherited from interface scala.Product

productArity, productElement, productElementName, productElementNames, productIterator, productPrefix

Constructor Details

Aggregator

public Aggregator(scala.Function1<V,C> createCombiner,
 scala.Function2<C,V,C> mergeValue,
 scala.Function2<C,C,C> mergeCombiners)

Method Details

createCombiner

public scala.Function1<V,C> createCombiner()

mergeValue

public scala.Function2<C,V,C> mergeValue()

mergeCombiners

public scala.Function2<C,C,C> mergeCombiners()

combineValuesByKey

public scala.collection.Iterator<scala.Tuple2<K,C>> combineValuesByKey(scala.collection.Iterator<scala.Product2<K,V>> iter,
 TaskContext context)

combineCombinersByKey

public scala.collection.Iterator<scala.Tuple2<K,C>> combineCombinersByKey(scala.collection.Iterator<scala.Product2<K,C>> iter,
 TaskContext context)