org.apache.hadoop.hbase.regionserver.wal
Class WALEditCodec

java.lang.Object
  extended by org.apache.hadoop.hbase.regionserver.wal.WALEditCodec
All Implemented Interfaces:
Codec

public class WALEditCodec
extends Object
implements Codec


Field Summary
static String WAL_EDIT_CODEC_CLASS_KEY
          Configuration key for a custom class to use when serializing the WALEdits to the HLog
 
Constructor Summary
WALEditCodec()
          Nullary Constructor - all subclass must support this to load from configuration.
 
Method Summary
static WALEditCodec create(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.hbase.regionserver.wal.CompressionContext compressionContext)
          Create and setup a WALEditCodec from the Configuration, if one has been specified.
 Decoder getDecoder(InputStream is)
           
 Encoder getEncoder(OutputStream os)
           
 void init(org.apache.hadoop.conf.Configuration conf)
          Initialize this - called exactly once after the object is instantiated and before any other method in this class.
 void setCompression(org.apache.hadoop.hbase.regionserver.wal.CompressionContext compression)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

WAL_EDIT_CODEC_CLASS_KEY

public static final String WAL_EDIT_CODEC_CLASS_KEY
Configuration key for a custom class to use when serializing the WALEdits to the HLog

See Also:
Constant Field Values
Constructor Detail

WALEditCodec

public WALEditCodec()
Nullary Constructor - all subclass must support this to load from configuration. Setup can be completed in the init(org.apache.hadoop.conf.Configuration) method.

This implementation defaults to having no compression on the resulting Encoder/ Decoder, though it can be added via setCompression(CompressionContext)

Method Detail

init

public void init(org.apache.hadoop.conf.Configuration conf)
Initialize this - called exactly once after the object is instantiated and before any other method in this class. By default, does nothing.

Parameters:
conf - Configuration from which to configure this

setCompression

public void setCompression(org.apache.hadoop.hbase.regionserver.wal.CompressionContext compression)

getDecoder

public Decoder getDecoder(InputStream is)
Specified by:
getDecoder in interface Codec

getEncoder

public Encoder getEncoder(OutputStream os)
Specified by:
getEncoder in interface Codec

create

public static WALEditCodec create(org.apache.hadoop.conf.Configuration conf,
                                  org.apache.hadoop.hbase.regionserver.wal.CompressionContext compressionContext)
                           throws IOException
Create and setup a WALEditCodec from the Configuration, if one has been specified. Fully prepares the codec for use in serialization.

Parameters:
conf - Configuration to read for the user-specified codec. If none is specified, uses a WALEditCodec.
compressionContext - compression to setup on the codec.
Returns:
a WALEditCodec ready for use.
Throws:
IOException - if the codec cannot be created


Copyright © 2013 The Apache Software Foundation. All Rights Reserved.