LongValueMax (Hadoop 1.2.1 API) (original) (raw)

org.apache.hadoop.mapred.lib.aggregate

Class LongValueMax

java.lang.Object extended by org.apache.hadoop.mapred.lib.aggregate.LongValueMax

All Implemented Interfaces:

ValueAggregator

public class LongValueMax

extends Object

implements ValueAggregator

This class implements a value aggregator that maintain the maximum of a sequence of long values.

Constructor Summary
LongValueMax() the default constructor

Method Summary
void	addNextValue(long newVal) add a value to the aggregator
void	addNextValue(Object val) add a value to the aggregator
ArrayList<String>	getCombinerOutput()
String	getReport()
long	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

LongValueMax

public LongValueMax()

the default constructor

Method Detail

addNextValue

public void addNextValue(Object val)

add a value to the aggregator

Specified by:

[addNextValue](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html#addNextValue%28java.lang.Object%29) in interface [ValueAggregator](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html "interface in org.apache.hadoop.mapred.lib.aggregate")

Parameters:

val - an object whose string representation represents a long value.

addNextValue

public void addNextValue(long newVal)

add a value to the aggregator

Parameters:

newVal - a long value.

getVal

public long getVal()

Returns:

the aggregated value

getReport

public String getReport()

Specified by:

[getReport](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html#getReport%28%29) in interface [ValueAggregator](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html "interface in org.apache.hadoop.mapred.lib.aggregate")

Returns:

the string representation of the aggregated value

reset

public void reset()

reset the aggregator

Specified by:

[reset](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html#reset%28%29) in interface [ValueAggregator](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html "interface in org.apache.hadoop.mapred.lib.aggregate")

getCombinerOutput

public ArrayList<String> getCombinerOutput()

Specified by:

[getCombinerOutput](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html#getCombinerOutput%28%29) in interface [ValueAggregator](../../../../../../org/apache/hadoop/mapred/lib/aggregate/ValueAggregator.html "interface in org.apache.hadoop.mapred.lib.aggregate")

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.