Class Bzip2Encoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelOutboundHandlerAdapter

io.netty.handler.codec.MessageToByteEncoder<ByteBuf>

io.netty.handler.codec.compression.Bzip2Encoder

All Implemented Interfaces:

ChannelHandler, ChannelOutboundHandler

public class Bzip2Encoder
extends MessageToByteEncoder<ByteBuf>

Compresses a ByteBuf using the Bzip2 algorithm. See Bzip2.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static enum	Bzip2Encoder.State	Current state of stream.

Nested classes/interfaces inherited from interface ChannelHandler

ChannelHandler.Sharable

Field Summary

Fields

Modifier and Type	Field	Description
private Bzip2BlockCompressor	blockCompressor	The compressor for the current block.
private ChannelHandlerContext	ctx	Used to interact with its ChannelPipeline and other handlers.
private Bzip2Encoder.State	currentState
private boolean	finished	(@code true} if the compressed stream has been finished, otherwise false.
private final int	streamBlockSize	The declared maximum block size of the stream (before final run-length decoding).
private int	streamCRC	The merged CRC of all blocks compressed so far.
private final Bzip2BitWriter	writer	A writer that provides bit-level writes.

Constructor Summary

Constructors

Constructor	Description
Bzip2Encoder()	Creates a new bzip2 encoder with the maximum (900,000 byte) block size.
Bzip2Encoder(int blockSizeMultiplier)	Creates a new bzip2 encoder with the specified blockSizeMultiplier.

Method Summary

Modifier and Type	Method	Description
ChannelFuture	close()	Close this Bzip2Encoder and so finish the encoding.
void	close(ChannelHandlerContext ctx, ChannelPromise promise)	Calls ChannelOutboundInvoker.close(ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline.
ChannelFuture	close(ChannelPromise promise)	Close this Bzip2Encoder and so finish the encoding.
private void	closeBlock(ByteBuf out)	Close current block and update streamCRC.
private ChannelHandlerContext	ctx()
protected void	encode(ChannelHandlerContext ctx, ByteBuf in, ByteBuf out)	Encode a message into a ByteBuf.
private ChannelFuture	finishEncode(ChannelHandlerContext ctx, ChannelPromise promise)
void	handlerAdded(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
boolean	isClosed()	Returns true if and only if the end of the compressed stream has been reached.

Methods inherited from class MessageToByteEncoder

acceptOutboundMessage, allocateBuffer, isPreferDirect, write

Methods inherited from class ChannelOutboundHandlerAdapter

bind, connect, deregister, disconnect, flush, read

Methods inherited from class ChannelHandlerAdapter

ensureNotSharable, exceptionCaught, handlerRemoved, isSharable

Methods inherited from class Object

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

Methods inherited from interface ChannelHandler

exceptionCaught, handlerRemoved

Field Details

currentState

private Bzip2Encoder.State currentState

writer

private final Bzip2BitWriter writer

A writer that provides bit-level writes.

streamBlockSize

private final int streamBlockSize

The declared maximum block size of the stream (before final run-length decoding).

streamCRC

private int streamCRC

The merged CRC of all blocks compressed so far.

blockCompressor

private Bzip2BlockCompressor blockCompressor

The compressor for the current block.

finished

private volatile boolean finished

(@code true} if the compressed stream has been finished, otherwise false.

ctx

private volatile ChannelHandlerContext ctx

Used to interact with its ChannelPipeline and other handlers.

Constructor Details

Bzip2Encoder

public Bzip2Encoder()

Creates a new bzip2 encoder with the maximum (900,000 byte) block size.

Bzip2Encoder

public Bzip2Encoder(int blockSizeMultiplier)

Creates a new bzip2 encoder with the specified blockSizeMultiplier.

Parameters:

blockSizeMultiplier - The Bzip2 block size as a multiple of 100,000 bytes (minimum 1, maximum 9). Larger block sizes require more memory for both compression and decompression, but give better compression ratios. 9 will usually be the best value to use.

Method Details

encode

protected void encode(ChannelHandlerContext ctx,
 ByteBuf in,
 ByteBuf out)
               throws Exception

Description copied from class: MessageToByteEncoder

Encode a message into a ByteBuf. This method will be called for each written message that can be handled by this encoder.

Specified by:

encode in class MessageToByteEncoder<ByteBuf>

Parameters:

ctx - the ChannelHandlerContext which this MessageToByteEncoder belongs to

in - the message to encode

out - the ByteBuf into which the encoded message will be written

Throws:

Exception - is thrown if an error occurs

closeBlock

private void closeBlock(ByteBuf out)

Close current block and update streamCRC.

isClosed

public boolean isClosed()

Returns true if and only if the end of the compressed stream has been reached.

close

public ChannelFuture close()

Close this Bzip2Encoder and so finish the encoding. The returned ChannelFuture will be notified once the operation completes.

close

public ChannelFuture close(ChannelPromise promise)

Close this Bzip2Encoder and so finish the encoding. The given ChannelFuture will be notified once the operation completes and will also be returned.

close

public void close(ChannelHandlerContext ctx,
 ChannelPromise promise)
           throws Exception

Description copied from class: ChannelOutboundHandlerAdapter

Calls ChannelOutboundInvoker.close(ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

close in interface ChannelOutboundHandler

Overrides:

close in class ChannelOutboundHandlerAdapter

Parameters:

ctx - the ChannelHandlerContext for which the close operation is made

promise - the ChannelPromise to notify once the operation completes

Throws:

Exception - thrown if an error occurs

finishEncode

private ChannelFuture finishEncode(ChannelHandlerContext ctx,
 ChannelPromise promise)

ctx

private ChannelHandlerContext ctx()

handlerAdded

public void handlerAdded(ChannelHandlerContext ctx)
                  throws Exception

Description copied from class: ChannelHandlerAdapter

Do nothing by default, sub-classes may override this method.

Specified by:

handlerAdded in interface ChannelHandler

Overrides:

handlerAdded in class ChannelHandlerAdapter

Throws:

Exception