org.apache.hadoop.chukwa.datacollection.writer

Class Dedup

java.lang.Object

org.apache.hadoop.chukwa.datacollection.writer.PipelineableWriter

org.apache.hadoop.chukwa.datacollection.writer.Dedup

All Implemented Interfaces:

ChukwaWriter

public class Dedup
extends PipelineableWriter

Uses a fixed size cache to check for and filter out duplicate chunks. Duplicate detection uses chunk metadata, not content.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.hadoop.chukwa.datacollection.writer.ChukwaWriter

ChukwaWriter.COMMIT_PENDING, ChukwaWriter.CommitStatus

Field Summary

Fields inherited from interface org.apache.hadoop.chukwa.datacollection.writer.ChukwaWriter

COMMIT_FAIL, COMMIT_OK

Constructor Summary

Constructors

Constructor and Description
Dedup()

Method Summary

Modifier and Type	Method and Description
ChukwaWriter.CommitStatus	add(List<Chunk> chunks) Called repeatedly with data that should be serialized.
void	close() Called once, indicating that the writer should close files and prepare to exit.
void	init(org.apache.hadoop.conf.Configuration c) Called once to initialize this writer.

Methods inherited from class org.apache.hadoop.chukwa.datacollection.writer.PipelineableWriter

setNextStage

Methods inherited from class java.lang.Object

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

Constructor Detail

Dedup

public Dedup()

Method Detail

add

public ChukwaWriter.CommitStatus add(List<Chunk> chunks)
                              throws WriterException

Description copied from interface: ChukwaWriter

Called repeatedly with data that should be serialized. Subclasses may assume that init() will be called before any calls to add(), and that add() won't be called after close().

Specified by:

add in interface ChukwaWriter

Overrides:

add in class PipelineableWriter

Parameters:

chunks - is a list of data to send

Returns:

CommitStatus

Throws:

WriterException - if error writing data

close

public void close()
           throws WriterException

Description copied from interface: ChukwaWriter

Called once, indicating that the writer should close files and prepare to exit.

Throws:

WriterException - if error writing data

init

public void init(org.apache.hadoop.conf.Configuration c)
          throws WriterException

Description copied from interface: ChukwaWriter

Called once to initialize this writer.

Parameters:

c - is Chukwa configuration

Throws:

WriterException - if error writing data