org.apache.hadoop.hbase.io.hfile

Class HFileDataBlockEncoderImpl

java.lang.Object

org.apache.hadoop.hbase.io.hfile.HFileDataBlockEncoderImpl

All Implemented Interfaces:

HFileDataBlockEncoder

@InterfaceAudience.Private
public class HFileDataBlockEncoderImpl
extends Object
implements HFileDataBlockEncoder

Do different kinds of data block encoding according to column family options.

Field Summary

Fields

Modifier and Type	Field and Description
private DataBlockEncoding	encoding

Fields inherited from interface org.apache.hadoop.hbase.io.hfile.HFileDataBlockEncoder

DATA_BLOCK_ENCODING

Constructor Summary

Constructors

Constructor and Description
HFileDataBlockEncoderImpl(DataBlockEncoding encoding) Do data block encoding with specified options.

Method Summary

Modifier and Type	Method and Description
static HFileDataBlockEncoder	createFromFileInfo(HFile.FileInfo fileInfo)
int	encode(Cell cell, HFileBlockEncodingContext encodingCtx, DataOutputStream out) Encodes a KeyValue.
void	endBlockEncoding(HFileBlockEncodingContext encodingCtx, DataOutputStream out, byte[] uncompressedBytesWithHeader, BlockType blockType) Ends encoding for a block of KeyValues.
DataBlockEncoding	getDataBlockEncoding()
DataBlockEncoding	getEffectiveEncodingInCache(boolean isCompaction)
HFileBlockDecodingContext	newDataBlockDecodingContext(HFileContext fileContext) create a encoder specific decoding context for reading.
HFileBlockEncodingContext	newDataBlockEncodingContext(byte[] dummyHeader, HFileContext fileContext) Create an encoder specific encoding context object for writing.
void	saveMetadata(HFile.Writer writer) Save metadata in HFile which will be written to disk
void	startBlockEncoding(HFileBlockEncodingContext encodingCtx, DataOutputStream out) Starts encoding for a block of KeyValues.
String	toString()
boolean	useEncodedScanner() Decides whether we should use a scanner over encoded blocks.
boolean	useEncodedScanner(boolean isCompaction)

Methods inherited from class java.lang.Object

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

Field Detail

encoding

private final DataBlockEncoding encoding

Constructor Detail

HFileDataBlockEncoderImpl

public HFileDataBlockEncoderImpl(DataBlockEncoding encoding)

Do data block encoding with specified options.

Parameters:

encoding - What kind of data block encoding will be used.

Method Detail

createFromFileInfo

public static HFileDataBlockEncoder createFromFileInfo(HFile.FileInfo fileInfo)
                                                throws IOException

Throws:

IOException

saveMetadata

public void saveMetadata(HFile.Writer writer)
                  throws IOException

Description copied from interface: HFileDataBlockEncoder

Save metadata in HFile which will be written to disk

Specified by:

saveMetadata in interface HFileDataBlockEncoder

Parameters:

writer - writer for a given HFile

Throws:

IOException - on disk problems

getDataBlockEncoding

public DataBlockEncoding getDataBlockEncoding()

Specified by:

getDataBlockEncoding in interface HFileDataBlockEncoder

Returns:

the data block encoding

useEncodedScanner

public boolean useEncodedScanner(boolean isCompaction)

getEffectiveEncodingInCache

public DataBlockEncoding getEffectiveEncodingInCache(boolean isCompaction)

Specified by:

getEffectiveEncodingInCache in interface HFileDataBlockEncoder

Returns:

the effective in-cache data block encoding, taking into account whether we are doing a compaction.

encode

public int encode(Cell cell,
                  HFileBlockEncodingContext encodingCtx,
                  DataOutputStream out)
           throws IOException

Description copied from interface: HFileDataBlockEncoder

Encodes a KeyValue.

Specified by:

encode in interface HFileDataBlockEncoder

Returns:

unencoded kv size

Throws:

IOException

useEncodedScanner

public boolean useEncodedScanner()

Description copied from interface: HFileDataBlockEncoder

Decides whether we should use a scanner over encoded blocks.

Specified by:

useEncodedScanner in interface HFileDataBlockEncoder

Returns:

Whether to use encoded scanner.

toString

public String toString()

Overrides:

toString in class Object

newDataBlockEncodingContext

public HFileBlockEncodingContext newDataBlockEncodingContext(byte[] dummyHeader,
                                                             HFileContext fileContext)

Description copied from interface: HFileDataBlockEncoder

Create an encoder specific encoding context object for writing. And the encoding context should also perform compression if compressionAlgorithm is valid.

Specified by:

newDataBlockEncodingContext in interface HFileDataBlockEncoder

Parameters:

dummyHeader - header bytes

fileContext - HFile meta data

Returns:

a new HFileBlockEncodingContext object

newDataBlockDecodingContext

public HFileBlockDecodingContext newDataBlockDecodingContext(HFileContext fileContext)

Description copied from interface: HFileDataBlockEncoder

create a encoder specific decoding context for reading. And the decoding context should also do decompression if compressionAlgorithm is valid.

Specified by:

newDataBlockDecodingContext in interface HFileDataBlockEncoder

Parameters:

fileContext - - HFile meta data

Returns:

a new HFileBlockDecodingContext object

startBlockEncoding

public void startBlockEncoding(HFileBlockEncodingContext encodingCtx,
                               DataOutputStream out)
                        throws IOException

Description copied from interface: HFileDataBlockEncoder

Starts encoding for a block of KeyValues. Call HFileDataBlockEncoder.endBlockEncoding(HFileBlockEncodingContext, DataOutputStream, byte[], BlockType) to finish encoding of a block.

Specified by:

startBlockEncoding in interface HFileDataBlockEncoder

Throws:

IOException

endBlockEncoding

public void endBlockEncoding(HFileBlockEncodingContext encodingCtx,
                             DataOutputStream out,
                             byte[] uncompressedBytesWithHeader,
                             BlockType blockType)
                      throws IOException

Description copied from interface: HFileDataBlockEncoder

Ends encoding for a block of KeyValues. Gives a chance for the encoder to do the finishing stuff for the encoded block. It must be called at the end of block encoding.

Specified by:

endBlockEncoding in interface HFileDataBlockEncoder

Throws:

IOException