org.apache.hadoop.mapreduce.lib.reduce

Class LongSumReducer<KEY>

java.lang.Object

org.apache.hadoop.mapreduce.Reducer<KEY,org.apache.hadoop.io.LongWritable,KEY,org.apache.hadoop.io.LongWritable>

org.apache.hadoop.mapreduce.lib.reduce.LongSumReducer<KEY>

public class LongSumReducer<KEY>
extends Reducer<KEY,org.apache.hadoop.io.LongWritable,KEY,org.apache.hadoop.io.LongWritable>

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Reducer

Reducer.Context

Constructor Summary

Constructors

Constructor and Description
LongSumReducer()

Method Summary

Methods

Modifier and Type	Method and Description
void	reduce(KEY key, java.lang.Iterable<org.apache.hadoop.io.LongWritable> values, Reducer.Context context) This method is called once for each key.

Methods inherited from class org.apache.hadoop.mapreduce.Reducer

cleanup, run, setup

Methods inherited from class java.lang.Object

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

Constructor Detail

LongSumReducer

public LongSumReducer()

Method Detail

reduce

public void reduce(KEY key,
          java.lang.Iterable<org.apache.hadoop.io.LongWritable> values,
          Reducer.Context context)
            throws java.io.IOException,
                   java.lang.InterruptedException

Description copied from class: Reducer

This method is called once for each key. Most applications will define their reduce class by overriding this method. The default implementation is an identity function.

Overrides:

reduce in class Reducer<KEY,org.apache.hadoop.io.LongWritable,KEY,org.apache.hadoop.io.LongWritable>

Throws:

java.io.IOException

java.lang.InterruptedException