org.apache.hadoop.hbase.regionserver.wal

Class WALCellCodec

java.lang.Object

org.apache.hadoop.hbase.regionserver.wal.WALCellCodec

All Implemented Interfaces:

Codec

Direct Known Subclasses:

SecureWALCellCodec

@InterfaceAudience.LimitedPrivate(value={"Coprocesssor","Phoenix","Configuration"})
public class WALCellCodec
extends Object
implements Codec

Compression in this class is lifted off Compressor/KeyValueCompression. This is a pure coincidence... they are independent and don't have to be compatible. This codec is used at server side for writing cells to WAL as well as for sending edits as part of the distributed splitting process.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static class	WALCellCodec.BaosAndCompressor
static interface	WALCellCodec.ByteStringCompressor
static interface	WALCellCodec.ByteStringUncompressor
(package private) static class	WALCellCodec.CompressedKvDecoder
(package private) static class	WALCellCodec.CompressedKvEncoder
static class	WALCellCodec.EnsureKvEncoder

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.codec.Codec

Codec.Decoder, Codec.Encoder

Field Summary

Fields

Modifier and Type	Field and Description
protected CompressionContext	compression
protected WALCellCodec.ByteStringUncompressor	statelessUncompressor
static String	WAL_CELL_CODEC_CLASS_KEY Configuration key for the class to use when encoding cells in the WAL

Constructor Summary

Constructors

Constructor and Description
WALCellCodec() All subclasses must implement a no argument constructor
WALCellCodec(org.apache.hadoop.conf.Configuration conf, CompressionContext compression) Default constructor - all subclasses must implement a constructor with this signature if they are to be dynamically loaded from the Configuration.

Method Summary

Modifier and Type	Method and Description
static WALCellCodec	create(org.apache.hadoop.conf.Configuration conf, CompressionContext compression) Create and setup a WALCellCodec from the CompressionContext.
static WALCellCodec	create(org.apache.hadoop.conf.Configuration conf, String cellCodecClsName, CompressionContext compression) Create and setup a WALCellCodec from the cellCodecClsName and CompressionContext, if cellCodecClsName is specified.
WALCellCodec.ByteStringCompressor	getByteStringCompressor()
WALCellCodec.ByteStringUncompressor	getByteStringUncompressor()
Codec.Decoder	getDecoder(ByteBuff buf)
Codec.Decoder	getDecoder(InputStream is)
Codec.Encoder	getEncoder(OutputStream os)
static Class<?>	getWALCellCodecClass(org.apache.hadoop.conf.Configuration conf)
private static byte[]	uncompressByteString(org.apache.hbase.thirdparty.com.google.protobuf.ByteString bs, Dictionary dict)

Methods inherited from class java.lang.Object

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

Field Detail

WAL_CELL_CODEC_CLASS_KEY

public static final String WAL_CELL_CODEC_CLASS_KEY

Configuration key for the class to use when encoding cells in the WAL

See Also:

Constant Field Values

compression

protected final CompressionContext compression

statelessUncompressor

protected final WALCellCodec.ByteStringUncompressor statelessUncompressor

Constructor Detail

WALCellCodec

public WALCellCodec()

All subclasses must implement a no argument constructor

WALCellCodec

public WALCellCodec(org.apache.hadoop.conf.Configuration conf,
                    CompressionContext compression)

Default constructor - all subclasses must implement a constructor with this signature if they are to be dynamically loaded from the Configuration.

Parameters:

conf - configuration to configure this

compression - compression the codec should support, can be null to indicate no compression

Method Detail

getWALCellCodecClass

public static Class<?> getWALCellCodecClass(org.apache.hadoop.conf.Configuration conf)

create

public static WALCellCodec create(org.apache.hadoop.conf.Configuration conf,
                                  String cellCodecClsName,
                                  CompressionContext compression)
                           throws UnsupportedOperationException

Create and setup a WALCellCodec from the cellCodecClsName and CompressionContext, if cellCodecClsName is specified. Otherwise Cell Codec classname is read from Configuration. Fully prepares the codec for use.

Parameters:

conf - Configuration to read for the user-specified codec. If none is specified, uses a WALCellCodec.

cellCodecClsName - name of codec

compression - compression the codec should use

Returns:

a WALCellCodec ready for use.

Throws:

UnsupportedOperationException - if the codec cannot be instantiated

create

public static WALCellCodec create(org.apache.hadoop.conf.Configuration conf,
                                  CompressionContext compression)
                           throws UnsupportedOperationException

Create and setup a WALCellCodec from the CompressionContext. Cell Codec classname is read from Configuration. Fully prepares the codec for use.

Parameters:

conf - Configuration to read for the user-specified codec. If none is specified, uses a WALCellCodec.

compression - compression the codec should use

Returns:

a WALCellCodec ready for use.

Throws:

UnsupportedOperationException - if the codec cannot be instantiated

uncompressByteString

private static byte[] uncompressByteString(org.apache.hbase.thirdparty.com.google.protobuf.ByteString bs,
                                           Dictionary dict)
                                    throws IOException

Throws:

IOException

getDecoder

public Codec.Decoder getDecoder(InputStream is)

Specified by:

getDecoder in interface Codec

getDecoder

public Codec.Decoder getDecoder(ByteBuff buf)

Specified by:

getDecoder in interface Codec

getEncoder

public Codec.Encoder getEncoder(OutputStream os)

Specified by:

getEncoder in interface Codec

getByteStringCompressor

public WALCellCodec.ByteStringCompressor getByteStringCompressor()

getByteStringUncompressor

public WALCellCodec.ByteStringUncompressor getByteStringUncompressor()