org.apache.hadoop.examples
Class WordStandardDeviation

java.lang.Object
  org.apache.hadoop.conf.Configured
      org.apache.hadoop.examples.WordStandardDeviation

All Implemented Interfaces:

org.apache.hadoop.conf.Configurable, org.apache.hadoop.util.Tool

public class WordStandardDeviation
extends org.apache.hadoop.conf.Configured
implements org.apache.hadoop.util.Tool

Nested Class Summary

static class	WordStandardDeviation.WordStandardDeviationMapper Maps words from line of text into 3 key-value pairs; one key-value pair for counting the word, one for counting its length, and one for counting the square of its length.
static class	WordStandardDeviation.WordStandardDeviationReducer Performs integer summation of all the values for each key.

Constructor Summary

WordStandardDeviation()

Method Summary

double	getStandardDeviation()
static void	main(String[] args)
int	run(String[] args)

Methods inherited from class org.apache.hadoop.conf.Configured

getConf, setConf

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.conf.Configurable

getConf, setConf

Constructor Detail

WordStandardDeviation

public WordStandardDeviation()

Method Detail

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception

run

public int run(String[] args)
        throws Exception

Specified by:

run in interface org.apache.hadoop.util.Tool

Throws:

Exception

getStandardDeviation

public double getStandardDeviation()