org.jboss.netty.handler.codec.http

Class HttpContentDecoder

java.lang.Object

org.jboss.netty.channel.SimpleChannelUpstreamHandler

org.jboss.netty.handler.codec.http.HttpContentDecoder

All Implemented Interfaces:

ChannelHandler, ChannelUpstreamHandler, LifeCycleAwareChannelHandler

Direct Known Subclasses:

HttpContentDecompressor

public abstract class HttpContentDecoder
extends SimpleChannelUpstreamHandler
implements LifeCycleAwareChannelHandler

Decodes the content of the received HttpRequest and HttpChunk. The original content is replaced with the new content decoded by the DecoderEmbedder, which is created by newContentDecoder(String). Once decoding is finished, the value of the 'Content-Encoding' header is set to the target content encoding, as returned by getTargetContentEncoding(String). Also, the 'Content-Length' header is updated to the length of the decoded content. If the content encoding of the original is not supported by the decoder, newContentDecoder(String) should return null so that no decoding occurs (i.e. pass-through).

Please note that this is an abstract class. You have to extend this class and implement newContentDecoder(String) properly to make this class functional. For example, refer to the source code of HttpContentDecompressor.

This handler must be placed after HttpMessageDecoder in the pipeline so that this handler can intercept HTTP requests after HttpMessageDecoder converts ChannelBuffers into HTTP requests.

Nested Class Summary

Nested classes/interfaces inherited from interface org.jboss.netty.channel.ChannelHandler

ChannelHandler.Sharable

Field Summary

Fields

Modifier and Type	Field and Description
private DecoderEmbedder<ChannelBuffer>	decoder

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	HttpContentDecoder() Creates a new instance.

Method Summary

Modifier and Type	Method and Description
void	afterAdd(ChannelHandlerContext ctx)
void	afterRemove(ChannelHandlerContext ctx)
void	beforeAdd(ChannelHandlerContext ctx)
void	beforeRemove(ChannelHandlerContext ctx)
void	channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e) Invoked when a Channel was closed and all its related resources were released.
private ChannelBuffer	decode(ChannelBuffer buf)
private ChannelBuffer	finishDecode()
protected java.lang.String	getTargetContentEncoding(java.lang.String contentEncoding) Returns the expected content encoding of the decoded content.
void	messageReceived(ChannelHandlerContext ctx, MessageEvent e) Invoked when a message object (e.g: ChannelBuffer) was received from a remote peer.
protected abstract DecoderEmbedder<ChannelBuffer>	newContentDecoder(java.lang.String contentEncoding) Returns a new DecoderEmbedder that decodes the HTTP message content encoded in the specified contentEncoding.

Methods inherited from class org.jboss.netty.channel.SimpleChannelUpstreamHandler

channelBound, channelConnected, channelDisconnected, channelInterestChanged, channelOpen, channelUnbound, childChannelClosed, childChannelOpen, exceptionCaught, handleUpstream, writeComplete

Methods inherited from class java.lang.Object

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

Field Detail

decoder

private DecoderEmbedder<ChannelBuffer> decoder

Constructor Detail

HttpContentDecoder

protected HttpContentDecoder()

Creates a new instance.

Method Detail

messageReceived

public void messageReceived(ChannelHandlerContext ctx,
                            MessageEvent e)
                     throws java.lang.Exception

Description copied from class: SimpleChannelUpstreamHandler

Invoked when a message object (e.g: ChannelBuffer) was received from a remote peer.

Overrides:

messageReceived in class SimpleChannelUpstreamHandler

Throws:

java.lang.Exception

channelClosed

public void channelClosed(ChannelHandlerContext ctx,
                          ChannelStateEvent e)
                   throws java.lang.Exception

Description copied from class: SimpleChannelUpstreamHandler

Invoked when a Channel was closed and all its related resources were released.

Overrides:

channelClosed in class SimpleChannelUpstreamHandler

Throws:

java.lang.Exception

newContentDecoder

protected abstract DecoderEmbedder<ChannelBuffer> newContentDecoder(java.lang.String contentEncoding)
                                                             throws java.lang.Exception

Returns a new DecoderEmbedder that decodes the HTTP message content encoded in the specified contentEncoding.

Parameters:

contentEncoding - the value of the "Content-Encoding" header

Returns:

a new DecoderEmbedder if the specified encoding is supported. null otherwise (alternatively, you can throw an exception to block unknown encoding).

Throws:

java.lang.Exception

getTargetContentEncoding

protected java.lang.String getTargetContentEncoding(java.lang.String contentEncoding)
                                             throws java.lang.Exception

Returns the expected content encoding of the decoded content. This method returns "identity" by default, which is the case for most decoders.

Parameters:

contentEncoding - the value of the "Content-Encoding" header

Returns:

the expected content encoding of the new content

Throws:

java.lang.Exception

decode

private ChannelBuffer decode(ChannelBuffer buf)

finishDecode

private ChannelBuffer finishDecode()

beforeAdd

public void beforeAdd(ChannelHandlerContext ctx)
               throws java.lang.Exception

Specified by:

beforeAdd in interface LifeCycleAwareChannelHandler

Throws:

java.lang.Exception

afterAdd

public void afterAdd(ChannelHandlerContext ctx)
              throws java.lang.Exception

Specified by:

afterAdd in interface LifeCycleAwareChannelHandler

Throws:

java.lang.Exception

beforeRemove

public void beforeRemove(ChannelHandlerContext ctx)
                  throws java.lang.Exception

Specified by:

beforeRemove in interface LifeCycleAwareChannelHandler

Throws:

java.lang.Exception

afterRemove

public void afterRemove(ChannelHandlerContext ctx)
                 throws java.lang.Exception

Specified by:

afterRemove in interface LifeCycleAwareChannelHandler

Throws:

java.lang.Exception