org.apache.hadoop.mapred.lib.aggregate
Class StringValueMin

java.lang.Object
  org.apache.hadoop.mapred.lib.aggregate.StringValueMin

All Implemented Interfaces:

ValueAggregator

public class StringValueMin
extends Object
implements ValueAggregator

This class implements a value aggregator that maintain the smallest of a sequence of strings.

Constructor Summary

StringValueMin()
the default constructor

Method Summary

void	addNextValue(Object val) add a value to the aggregator
ArrayList<String>	getCombinerOutput()
String	getReport()
String	getVal()
void	reset() reset the aggregator

Methods inherited from class java.lang.Object

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

Constructor Detail

StringValueMin

public StringValueMin()

the default constructor

Method Detail

addNextValue

public void addNextValue(Object val)

add a value to the aggregator

Specified by:

addNextValue in interface ValueAggregator

Parameters:

val - a string.

getVal

public String getVal()

Returns:

the aggregated value

getReport

public String getReport()

Specified by:

getReport in interface ValueAggregator

Returns:

the string representation of the aggregated value

reset

public void reset()

reset the aggregator

Specified by:

reset in interface ValueAggregator

getCombinerOutput

public ArrayList<String> getCombinerOutput()

Specified by:

getCombinerOutput in interface ValueAggregator

Returns:

return an array of one element. The element is a string representation of the aggregated value. The return value is expected to be used by the a combiner.