Class ZlibDecoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.ByteToMessageDecoder

io.netty.handler.codec.compression.ZlibDecoder

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler

Direct Known Subclasses:

JdkZlibDecoder, JZlibDecoder

public abstract class ZlibDecoder
extends ByteToMessageDecoder

Decompresses a ByteBuf using the deflate algorithm.

Nested Class Summary

Nested classes/interfaces inherited from class ByteToMessageDecoder

ByteToMessageDecoder.Cumulator

Modifier and Type	Class	Description
static interface	ByteToMessageDecoder.Cumulator	Cumulate ByteBufs.

Nested classes/interfaces inherited from interface ChannelHandler

ChannelHandler.Sharable

Modifier and Type	Interface	Description
static @interface	ChannelHandler.Sharable	Indicates that the same instance of the annotated ChannelHandler can be added to one or more ChannelPipelines multiple times without a race condition.

Field Summary

Fields

Modifier and Type	Field	Description
protected final int	maxAllocation	Maximum allowed size of the decompression buffer.

Fields inherited from class ByteToMessageDecoder

COMPOSITE_CUMULATOR, MERGE_CUMULATOR

Modifier and Type	Field	Description
static final ByteToMessageDecoder.Cumulator	COMPOSITE_CUMULATOR	Cumulate ByteBufs by add them to a CompositeByteBuf and so do no memory copy whenever possible.
static final ByteToMessageDecoder.Cumulator	MERGE_CUMULATOR	Cumulate ByteBufs by merge them into one ByteBuf's, using memory copies.

Constructor Summary

Constructors

Constructor	Description
ZlibDecoder()	Same as ZlibDecoder(int) with maxAllocation = 0.
ZlibDecoder(int maxAllocation)	Construct a new ZlibDecoder.

Method Summary

Modifier and Type	Method	Description
protected void	decompressionBufferExhausted(ByteBuf buffer)	Called when the decompression buffer cannot be expanded further.
abstract boolean	isClosed()	Returns true if and only if the end of the compressed stream has been reached.
protected ByteBuf	prepareDecompressBuffer(ChannelHandlerContext ctx, ByteBuf buffer, int preferredSize)	Allocate or expand the decompression buffer, without exceeding the maximum allocation.

Methods inherited from class ByteToMessageDecoder

actualReadableBytes, callDecode, channelInactive, channelRead, channelReadComplete, decode, decodeLast, discardSomeReadBytes, handlerRemoved, handlerRemoved0, internalBuffer, isSingleDecode, setCumulator, setDiscardAfterReads, setSingleDecode, userEventTriggered

Modifier and Type	Method	Description
protected int	actualReadableBytes()	Returns the actual number of readable bytes in the internal cumulative buffer of this decoder.
protected void	callDecode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out)	Called once data should be decoded from the given ByteBuf.
void	channelInactive(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelInactive() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelRead(ChannelHandlerContext ctx, Object input)	Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelReadComplete(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelReadComplete() to forward to the next ChannelInboundHandler in the ChannelPipeline.
protected abstract void	decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out)	Decode the from one ByteBuf to an other.
protected void	decodeLast(ChannelHandlerContext ctx, ByteBuf in, List<Object> out)	Is called one last time when the ChannelHandlerContext goes in-active.
protected final void	discardSomeReadBytes()
final void	handlerRemoved(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
protected void	handlerRemoved0(ChannelHandlerContext ctx)	Gets called after the ByteToMessageDecoder was removed from the actual context and it doesn't handle events anymore.
protected ByteBuf	internalBuffer()	Returns the internal cumulative buffer of this decoder.
boolean	isSingleDecode()	If true then only one message is decoded on each ByteToMessageDecoder.channelRead(ChannelHandlerContext, Object) call.
void	setCumulator(ByteToMessageDecoder.Cumulator cumulator)	Set the ByteToMessageDecoder.Cumulator to use for cumulate the received ByteBufs.
void	setDiscardAfterReads(int discardAfterReads)	Set the number of reads after which ByteBuf.discardSomeReadBytes() are called and so free up memory.
void	setSingleDecode(boolean singleDecode)	If set then only one message is decoded on each ByteToMessageDecoder.channelRead(ChannelHandlerContext, Object) call.
void	userEventTriggered(ChannelHandlerContext ctx, Object evt)	Calls ChannelHandlerContext.fireUserEventTriggered(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.

Methods inherited from class ChannelInboundHandlerAdapter

channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

Modifier and Type	Method	Description
void	channelActive(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelActive() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelRegistered(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelRegistered() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelUnregistered(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelUnregistered() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelWritabilityChanged(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelWritabilityChanged() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	exceptionCaught(ChannelHandlerContext ctx, Throwable cause)	Calls ChannelHandlerContext.fireExceptionCaught(Throwable) to forward to the next ChannelHandler in the ChannelPipeline.

Methods inherited from class ChannelHandlerAdapter

ensureNotSharable, handlerAdded, isSharable

Modifier and Type	Method	Description
protected void	ensureNotSharable()	Throws IllegalStateException if ChannelHandlerAdapter.isSharable() returns true
void	handlerAdded(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
boolean	isSharable()	Return true if the implementation is ChannelHandler.Sharable and so can be added to different ChannelPipelines.

Methods inherited from class Object

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

Field Details

maxAllocation

protected final int maxAllocation

Maximum allowed size of the decompression buffer.

Constructor Details

ZlibDecoder

public ZlibDecoder()

Same as ZlibDecoder(int) with maxAllocation = 0.

ZlibDecoder

public ZlibDecoder(int maxAllocation)

Construct a new ZlibDecoder.

Parameters:

maxAllocation - Maximum size of the decompression buffer. Must be >= 0. If zero, maximum size is decided by the ByteBufAllocator.

Method Details

isClosed

public abstract boolean isClosed()

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

prepareDecompressBuffer

protected ByteBuf prepareDecompressBuffer(ChannelHandlerContext ctx,
 ByteBuf buffer,
 int preferredSize)

Allocate or expand the decompression buffer, without exceeding the maximum allocation. Calls decompressionBufferExhausted(ByteBuf) if the buffer is full and cannot be expanded further.

decompressionBufferExhausted

protected void decompressionBufferExhausted(ByteBuf buffer)

Called when the decompression buffer cannot be expanded further. Default implementation is a no-op, but subclasses can override in case they want to do something before the DecompressionException is thrown, such as log the data that was decompressed so far.