org.apache.hadoop.examples.pi

Class DistSum.MapSide.SummingMapper

java.lang.Object

org.apache.hadoop.mapreduce.Mapper<NullWritable,SummationWritable,NullWritable,TaskResult>

org.apache.hadoop.examples.pi.DistSum.MapSide.SummingMapper

Enclosing class:

DistSum.MapSide

public static class DistSum.MapSide.SummingMapper
extends Mapper<NullWritable,SummationWritable,NullWritable,TaskResult>

A mapper which computes sums

Nested Class Summary

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

Mapper.Context

Constructor Summary

Constructors

Constructor and Description
DistSum.MapSide.SummingMapper()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	map(NullWritable nw, SummationWritable sigma, Mapper.Context context) Called once for each key/value pair in the input split.

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

cleanup, run, setup

Methods inherited from class java.lang.Object

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

Constructor Detail

DistSum.MapSide.SummingMapper

public DistSum.MapSide.SummingMapper()

Method Detail

map

protected void map(NullWritable nw,
       SummationWritable sigma,
       Mapper.Context context)
            throws IOException,
                   InterruptedException

Description copied from class: Mapper

Called once for each key/value pair in the input split. Most applications should override this, but the default is the identity function.

Overrides:

map in class Mapper<NullWritable,SummationWritable,NullWritable,TaskResult>

Throws:

IOException

InterruptedException