org.apache.hadoop.hbase.io

Class TagCompressionContext

java.lang.Object

org.apache.hadoop.hbase.io.TagCompressionContext

@InterfaceAudience.Private
public class TagCompressionContext
extends Object

Context that holds the dictionary for Tag compression and doing the compress/uncompress. This will be used for compressing tags while writing into HFiles and WALs.

Field Summary

Fields

Modifier and Type	Field and Description
private Dictionary	tagDict

Constructor Summary

Constructors

Constructor and Description
TagCompressionContext(Class<? extends Dictionary> dictType, int dictCapacity)

Method Summary

Modifier and Type	Method and Description
void	clear()
void	compressTags(OutputStream out, byte[] in, int offset, int length) Compress tags one by one and writes to the OutputStream.
void	compressTags(OutputStream out, ByteBuffer in, int offset, int length) Compress tags one by one and writes to the OutputStream.
int	uncompressTags(ByteBuff src, byte[] dest, int offset, int length) Uncompress tags from the input ByteBuffer and writes to the destination array.
void	uncompressTags(InputStream src, byte[] dest, int offset, int length) Uncompress tags from the InputStream and writes to the destination array.
void	uncompressTags(InputStream src, ByteBuffer dest, int length) Uncompress tags from the InputStream and writes to the destination buffer.

Methods inherited from class java.lang.Object

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

Field Detail

tagDict

private final Dictionary tagDict

Constructor Detail

TagCompressionContext

public TagCompressionContext(Class<? extends Dictionary> dictType,
                             int dictCapacity)
                      throws SecurityException,
                             NoSuchMethodException,
                             InstantiationException,
                             IllegalAccessException,
                             InvocationTargetException

Throws:

SecurityException

NoSuchMethodException

InstantiationException

IllegalAccessException

InvocationTargetException

Method Detail

clear

public void clear()

compressTags

public void compressTags(OutputStream out,
                         byte[] in,
                         int offset,
                         int length)
                  throws IOException

Compress tags one by one and writes to the OutputStream.

Parameters:

out - Stream to which the compressed tags to be written

in - Source where tags are available

offset - Offset for the tags bytes

length - Length of all tag bytes

Throws:

IOException

compressTags

public void compressTags(OutputStream out,
                         ByteBuffer in,
                         int offset,
                         int length)
                  throws IOException

Compress tags one by one and writes to the OutputStream.

Parameters:

out - Stream to which the compressed tags to be written

in - Source buffer where tags are available

offset - Offset for the tags byte buffer

length - Length of all tag bytes

Throws:

IOException

uncompressTags

public void uncompressTags(InputStream src,
                           byte[] dest,
                           int offset,
                           int length)
                    throws IOException

Uncompress tags from the InputStream and writes to the destination array.

Parameters:

src - Stream where the compressed tags are available

dest - Destination array where to write the uncompressed tags

offset - Offset in destination where tags to be written

length - Length of all tag bytes

Throws:

IOException

uncompressTags

public int uncompressTags(ByteBuff src,
                          byte[] dest,
                          int offset,
                          int length)
                   throws IOException

Uncompress tags from the input ByteBuffer and writes to the destination array.

Parameters:

src - Buffer where the compressed tags are available

dest - Destination array where to write the uncompressed tags

offset - Offset in destination where tags to be written

length - Length of all tag bytes

Returns:

bytes count read from source to uncompress all tags.

Throws:

IOException

uncompressTags

public void uncompressTags(InputStream src,
                           ByteBuffer dest,
                           int length)
                    throws IOException

Uncompress tags from the InputStream and writes to the destination buffer.

Parameters:

src - Stream where the compressed tags are available

dest - Destination buffer where to write the uncompressed tags

length - Length of all tag bytes

Throws:

IOException - when the dictionary does not have the entry