Package org.apache.hadoop.mapred

Class MapReduceBase

java.lang.Object

org.apache.hadoop.mapred.MapReduceBase

All Implemented Interfaces:

Closeable, AutoCloseable, Closeable, JobConfigurable

Direct Known Subclasses:

IdentityMapper, IdentityReducer, InverseMapper, LongSumReducer, RegexMapper, TokenCountMapper

@Public
@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

Constructors

Constructor	Description
MapReduceBase()

Method Summary

Modifier and Type	Method	Description
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 Details

MapReduceBase

public MapReduceBase()

Method Details

close

public void close()
           throws IOException

Default implementation that does nothing.

Specified by:

close in interface AutoCloseable

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