org.apache.hadoop.mapred.lib

Class FilterOutputFormat<K,V>

java.lang.Object

org.apache.hadoop.mapred.lib.FilterOutputFormat<K,V>

All Implemented Interfaces:

OutputFormat<K,V>

Direct Known Subclasses:

LazyOutputFormat

@InterfaceAudience.Public
 @InterfaceStability.Stable
public class FilterOutputFormat<K,V>
extends Object
implements OutputFormat<K,V>

FilterOutputFormat is a convenience class that wraps OutputFormat.

Field Summary

Fields

Modifier and Type	Field and Description
protected OutputFormat<K,V>	baseOut

Constructor Summary

Constructors

Constructor and Description
FilterOutputFormat()
FilterOutputFormat(OutputFormat<K,V> out) Create a FilterOutputFormat based on the supplied output format.

Method Summary

Modifier and Type	Method and Description
void	checkOutputSpecs(FileSystem ignored, JobConf job) Check for validity of the output-specification for the job.
RecordWriter<K,V>	getRecordWriter(FileSystem ignored, JobConf job, String name, Progressable progress) Get the RecordWriter for the given job.

Methods inherited from class java.lang.Object

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

Field Detail

baseOut

protected OutputFormat<K,V> baseOut

Constructor Detail

FilterOutputFormat

public FilterOutputFormat()

FilterOutputFormat

public FilterOutputFormat(OutputFormat<K,V> out)

Create a FilterOutputFormat based on the supplied output format.

Parameters:

out - the underlying OutputFormat

Method Detail

getRecordWriter

public RecordWriter<K,V> getRecordWriter(FileSystem ignored,
                                         JobConf job,
                                         String name,
                                         Progressable progress)
                                  throws IOException

Description copied from interface: OutputFormat

Get the RecordWriter for the given job.

Specified by:

getRecordWriter in interface OutputFormat<K,V>

job - configuration for the job whose output is being written.

name - the unique name for this part of the output.

progress - mechanism for reporting progress while writing to file.

Returns:

a RecordWriter to write the output for the job.

Throws:

IOException

checkOutputSpecs

public void checkOutputSpecs(FileSystem ignored,
                             JobConf job)
                      throws IOException

Description copied from interface: OutputFormat

Check for validity of the output-specification for the job.

This is to validate the output specification for the job when it is a job is submitted. Typically checks that it does not already exist, throwing an exception when it already exists, so that output is not overwritten.

Implementations which write to filesystems which support delegation tokens usually collect the tokens for the destination path(s) and attach them to the job configuration.

Specified by:

checkOutputSpecs in interface OutputFormat<K,V>

job - job configuration.

Throws:

IOException - when output should not be attempted