Package org.apache.hadoop.mapreduce.lib.output

Class FilterOutputFormat<K,V>

java.lang.Object

org.apache.hadoop.mapreduce.OutputFormat<K,V>

org.apache.hadoop.mapreduce.lib.output.FilterOutputFormat<K,V>

Direct Known Subclasses:

LazyOutputFormat

@Public
@Stable
public class FilterOutputFormat<K,V>
extends OutputFormat<K,V>

FilterOutputFormat is a convenience class that wraps OutputFormat.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	org.apache.hadoop.mapreduce.lib.output.FilterOutputFormat.FilterRecordWriter<K,V>	FilterRecordWriter is a convenience wrapper class that extends the RecordWriter.

Field Summary

Fields

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

Constructor Summary

Constructors

Constructor	Description
FilterOutputFormat()
FilterOutputFormat(OutputFormat<K,V> baseOut)	Create a FilterOutputFormat based on the underlying output format.

Method Summary

Modifier and Type	Method	Description
void	checkOutputSpecs(JobContext context)	Check for validity of the output-specification for the job.
OutputCommitter	getOutputCommitter(TaskAttemptContext context)	Get the output committer for this output format.
RecordWriter<K,V>	getRecordWriter(TaskAttemptContext context)	Get the RecordWriter for the given task.

Methods inherited from class java.lang.Object

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

Field Details

baseOut

protected OutputFormat<K,V> baseOut

Constructor Details

FilterOutputFormat

public FilterOutputFormat()

FilterOutputFormat

public FilterOutputFormat(OutputFormat<K,V> baseOut)

Create a FilterOutputFormat based on the underlying output format.

Parameters:

baseOut - the underlying OutputFormat

Method Details

getRecordWriter

public RecordWriter<K,V> getRecordWriter(TaskAttemptContext context)
                                  throws IOException,
InterruptedException

Description copied from class: OutputFormat

Get the RecordWriter for the given task.

Specified by:

getRecordWriter in class OutputFormat<K,V>

Parameters:

context - the information about the current task.

Returns:

a RecordWriter to write the output for the job.

Throws:

IOException

InterruptedException

checkOutputSpecs

public void checkOutputSpecs(JobContext context)
                      throws IOException,
InterruptedException

Description copied from class: 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 context's JobConf.

Specified by:

checkOutputSpecs in class OutputFormat<K,V>

Parameters:

context - information about the job

Throws:

IOException - when output should not be attempted

InterruptedException

getOutputCommitter

public OutputCommitter getOutputCommitter(TaskAttemptContext context)
                                   throws IOException,
InterruptedException

Description copied from class: OutputFormat

Get the output committer for this output format. This is responsible for ensuring the output is committed correctly.

Specified by:

getOutputCommitter in class OutputFormat<K,V>

Parameters:

context - the task context

Returns:

an output committer

Throws:

IOException

InterruptedException