org.snf4j.core.codec.zip

Class ZlibDecoder

java.lang.Object

org.snf4j.core.codec.zip.ZlibCodec

org.snf4j.core.codec.zip.ZlibDecoder

All Implemented Interfaces:

ICodec<byte[],ByteBuffer>, IDecoder<byte[],ByteBuffer>, IEventDrivenCodec

Direct Known Subclasses:

GzipDecoder

public class ZlibDecoder
extends ZlibCodec
implements IDecoder<byte[],ByteBuffer>, IEventDrivenCodec

Decompresses an array of bytes using the zlib compression.

Author:

SNF4J.ORG

Nested Class Summary

Nested classes/interfaces inherited from class org.snf4j.core.codec.zip.ZlibCodec

ZlibCodec.Mode

Field Summary

Fields

Modifier and Type	Field and Description
protected Inflater	inflater The decompressor used by this class to decompress data.

Constructor Summary

Constructors

Modifier	Constructor and Description
	ZlibDecoder() Creates a new zlib decoder with the default mode (ZLIB).
	ZlibDecoder(byte[] dictionary) Creates a new zlib decoder with a preset dictionary for decompression and the default mode (ZLIB).
protected	ZlibDecoder(byte[] dictionary, ZlibCodec.Mode mode) Creates a new zlib decoder with a preset dictionary for decompression and the mode.
	ZlibDecoder(ZlibCodec.Mode mode) Creates a new zlib decoder with the specified mode.

Method Summary

Modifier and Type	Method and Description
void	added(ISession session, ICodecPipeline pipeline) Does nothing.
void	decode(ISession session, byte[] data, List<ByteBuffer> out) Decompresses the input data.
void	event(ISession session, SessionEvent event) Finishes the decompression when the associated session is ending (SessionEvent.ENDING).
protected int	inflateBound(int len) Returns upper bound on the decompressed size.
boolean	isFinished() Tells if the decompression has been finished.
protected boolean	postFinish(ISession session, ByteBuffer in) Called right after the decompression has been finished.
protected void	postInflate(ISession session, byte[] data, int off, int len) Called right after decompression of a portion of compressed data.
protected void	preInflate(ISession session, ByteBuffer in) Called right before decompression of a portion of compressed data.
void	removed(ISession session, ICodecPipeline pipeline) Does nothing.

Methods inherited from class org.snf4j.core.codec.zip.ZlibCodec

getInboundType, getOutboundType

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.snf4j.core.codec.ICodec

getInboundType, getOutboundType

Field Detail

inflater

protected Inflater inflater

The decompressor used by this class to decompress data.

Constructor Detail

ZlibDecoder

public ZlibDecoder()

Creates a new zlib decoder with the default mode (ZLIB).

ZlibDecoder

public ZlibDecoder(byte[] dictionary)

Creates a new zlib decoder with a preset dictionary for decompression and the default mode (ZLIB).

Parameters:

dictionary - the preset dictionary or null if no preset dictionary should be used

ZlibDecoder

public ZlibDecoder(ZlibCodec.Mode mode)

Creates a new zlib decoder with the specified mode.

Parameters:

mode - the mode for the zlib decoder

Throws:

NullPointerException - if the mode is null

ZlibDecoder

protected ZlibDecoder(byte[] dictionary,
                      ZlibCodec.Mode mode)

Creates a new zlib decoder with a preset dictionary for decompression and the mode.

Parameters:

dictionary - the preset dictionary or null if no preset dictionary should be used

mode - the mode for the zlib decoder

Method Detail

inflateBound

protected int inflateBound(int len)

Returns upper bound on the decompressed size.

Parameters:

len - the length of the compressed data.

Returns:

the upper bound

preInflate

protected void preInflate(ISession session,
                          ByteBuffer in)
                   throws Exception

Called right before decompression of a portion of compressed data. It can be used, for example, to parse a customized header. All data being part of the header have to be consumed from the input buffer.

Parameters:

session - the session object the decoder is associated with

in - the compressed input data

Throws:

Exception - if an error has occurred

postInflate

protected void postInflate(ISession session,
                           byte[] data,
                           int off,
                           int len)
                    throws Exception

Called right after decompression of a portion of compressed data. It can be used, for example, to compute the CRC-32 of a decompressed data stream.

Parameters:

session - the session object the decoder is associated with

data - an array with decompressed data

off - the start offset in the array at which the data should be read

len - the number of bytes to read

Throws:

Exception - if an error has occurred

postFinish

protected boolean postFinish(ISession session,
                             ByteBuffer in)
                      throws Exception

Called right after the decompression has been finished. It can be used, for example, to parse a customized footer. All data being part of the footer have to be consumed from the input buffer.

Parameters:

session - the session object the decoder is associated with

in - the compressed input data

Returns:

true if all bytes forming the footer has been already consumed

Throws:

Exception - if an error has occurred

isFinished

public boolean isFinished()

Tells if the decompression has been finished.

Returns:

true if the decompression has been finished.

decode

public void decode(ISession session,
                   byte[] data,
                   List<ByteBuffer> out)
            throws Exception

Decompresses the input data.

Specified by:

decode in interface IDecoder<byte[],ByteBuffer>

Parameters:

session - the ISession which the passed data belongs to

data - the data to decode to another one

out - the List to which the decoded data should be added, or null if O is Void

Throws:

Exception - is thrown, if an error occur

added

public void added(ISession session,
                  ICodecPipeline pipeline)

Does nothing.

Specified by:

added in interface IEventDrivenCodec

Parameters:

session - the session the pipeline is associated with

pipeline - the pipeline the codec has been added to

event

public void event(ISession session,
                  SessionEvent event)

Finishes the decompression when the associated session is ending (SessionEvent.ENDING).

Specified by:

event in interface IEventDrivenCodec

Parameters:

session - the session which state is changing

event - the session event

removed

public void removed(ISession session,
                    ICodecPipeline pipeline)

Does nothing.

Specified by:

removed in interface IEventDrivenCodec

Parameters:

session - the session the pipeline is associated with

pipeline - the pipeline the codec has been removed from