org.apache.hadoop.mapred

Class MROutputFiles

java.lang.Object

org.apache.hadoop.mapred.MapOutputFile

org.apache.hadoop.mapred.MROutputFiles

All Implemented Interfaces:

Configurable

@InterfaceAudience.Private
@InterfaceStability.Unstable
public class MROutputFiles
extends MapOutputFile

Manipulate the working area for the transient store for maps and reduces. This class is used by map and reduce tasks to identify the directories that they need to write to/read from for intermediate files. The callers of these methods are from the Child running the Task.

Constructor Summary

Constructors

Constructor and Description
MROutputFiles()

Method Summary

Methods

Modifier and Type	Method and Description
Path	getInputFile(int mapId) Return a local reduce input file created earlier
Path	getInputFileForWrite(TaskID mapId, long size) Create a local reduce input file name.
Path	getOutputFile() Return the path to local map output file created earlier
Path	getOutputFileForWrite(long size) Create a local map output file name.
Path	getOutputFileForWriteInVolume(Path existing) Create a local map output file name on the same volume.
Path	getOutputIndexFile() Return the path to a local map output index file created earlier
Path	getOutputIndexFileForWrite(long size) Create a local map output index file name.
Path	getOutputIndexFileForWriteInVolume(Path existing) Create a local map output index file name on the same volume.
Path	getSpillFile(int spillNumber) Return a local map spill file created earlier.
Path	getSpillFileForWrite(int spillNumber, long size) Create a local map spill file name.
Path	getSpillIndexFile(int spillNumber) Return a local map spill index file created earlier
Path	getSpillIndexFileForWrite(int spillNumber, long size) Create a local map spill index file name.
void	removeAll() Removes all of the files related to a task.
void	setConf(Configuration conf) Set the configuration to be used by this object.

Methods inherited from class org.apache.hadoop.mapred.MapOutputFile

getConf

Methods inherited from class java.lang.Object

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

Constructor Detail

MROutputFiles

public MROutputFiles()

Method Detail

getOutputFile

public Path getOutputFile()
                   throws IOException

Return the path to local map output file created earlier

Specified by:

getOutputFile in class MapOutputFile

Returns:

path

Throws:

IOException

getOutputFileForWrite

public Path getOutputFileForWrite(long size)
                           throws IOException

Create a local map output file name.

Specified by:

getOutputFileForWrite in class MapOutputFile

Parameters:

size - the size of the file

Returns:

path

Throws:

IOException

getOutputFileForWriteInVolume

public Path getOutputFileForWriteInVolume(Path existing)

Create a local map output file name on the same volume.

Specified by:

getOutputFileForWriteInVolume in class MapOutputFile

getOutputIndexFile

public Path getOutputIndexFile()
                        throws IOException

Return the path to a local map output index file created earlier

Specified by:

getOutputIndexFile in class MapOutputFile

Returns:

path

Throws:

IOException

getOutputIndexFileForWrite

public Path getOutputIndexFileForWrite(long size)
                                throws IOException

Create a local map output index file name.

Specified by:

getOutputIndexFileForWrite in class MapOutputFile

Parameters:

size - the size of the file

Returns:

path

Throws:

IOException

getOutputIndexFileForWriteInVolume

public Path getOutputIndexFileForWriteInVolume(Path existing)

Create a local map output index file name on the same volume.

Specified by:

getOutputIndexFileForWriteInVolume in class MapOutputFile

getSpillFile

public Path getSpillFile(int spillNumber)
                  throws IOException

Return a local map spill file created earlier.

Specified by:

getSpillFile in class MapOutputFile

Parameters:

spillNumber - the number

Returns:

path

Throws:

IOException

getSpillFileForWrite

public Path getSpillFileForWrite(int spillNumber,
                        long size)
                          throws IOException

Create a local map spill file name.

Specified by:

getSpillFileForWrite in class MapOutputFile

Parameters:

spillNumber - the number

size - the size of the file

Returns:

path

Throws:

IOException

getSpillIndexFile

public Path getSpillIndexFile(int spillNumber)
                       throws IOException

Return a local map spill index file created earlier

Specified by:

getSpillIndexFile in class MapOutputFile

Parameters:

spillNumber - the number

Returns:

path

Throws:

IOException

getSpillIndexFileForWrite

public Path getSpillIndexFileForWrite(int spillNumber,
                             long size)
                               throws IOException

Create a local map spill index file name.

Specified by:

getSpillIndexFileForWrite in class MapOutputFile

Parameters:

spillNumber - the number

size - the size of the file

Returns:

path

Throws:

IOException

getInputFile

public Path getInputFile(int mapId)
                  throws IOException

Return a local reduce input file created earlier

Specified by:

getInputFile in class MapOutputFile

Parameters:

mapId - a map task id

Returns:

path

Throws:

IOException

getInputFileForWrite

public Path getInputFileForWrite(TaskID mapId,
                        long size)
                          throws IOException

Create a local reduce input file name.

Specified by:

getInputFileForWrite in class MapOutputFile

Parameters:

mapId - a map task id

size - the size of the file

Returns:

path

Throws:

IOException

removeAll

public void removeAll()
               throws IOException

Removes all of the files related to a task.

Specified by:

removeAll in class MapOutputFile

Throws:

IOException

setConf

public void setConf(Configuration conf)

Description copied from interface: Configurable

Set the configuration to be used by this object.

Specified by:

setConf in interface Configurable

Overrides:

setConf in class MapOutputFile