org.apache.hadoop.mapred
Class MapReduceBase

java.lang.Object
  org.apache.hadoop.mapred.MapReduceBase

All Implemented Interfaces:

Closeable, JobConfigurable

Direct Known Subclasses:

IdentityMapper, IdentityReducer, InverseMapper, LongSumReducer, RegexMapper, TokenCountMapper

@InterfaceAudience.Public
@InterfaceStability.Stable
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