org.apache.hadoop.mapred
Class MapReduceBase

java.lang.Object
  extended by org.apache.hadoop.mapred.MapReduceBase
All Implemented Interfaces:
Closeable, JobConfigurable
Direct Known Subclasses:
DistributedPentomino.PentMap, IdentityMapper, IdentityReducer, IndexUpdateCombiner, IndexUpdateMapper, IndexUpdateReducer, InverseMapper, LongSumReducer, MultiFileWordCount.MapClass, PiEstimator.PiMapper, PiEstimator.PiReducer, RegexMapper, TeraGen.SortGenMapper, TokenCountMapper

public class MapReduceBase
extends Object
implements Closeable, JobConfigurable

Base class for Mapper and Reducer implementations.

Provides default no-op implementations for a few methods, most non-trivial applications need to override some of them.


Constructor Summary
MapReduceBase()
           
 
Method Summary
 void close()
          Default implementation that does nothing.
 void configure(JobConf job)
          Default implementation that does nothing.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

MapReduceBase

public MapReduceBase()
Method Detail

close

public void close()
           throws IOException
Default implementation that does nothing.

Specified by:
close in interface Closeable
Throws:
IOException

configure

public void configure(JobConf job)
Default implementation that does nothing.

Specified by:
configure in interface JobConfigurable
Parameters:
job - the configuration


Copyright © 2009 The Apache Software Foundation