public abstract class HttpContentDecoder extends MessageToMessageDecoder<HttpObject>
HttpRequest
and HttpContent
.
The original content is replaced with the new content decoded by the
EmbeddedChannel
, 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 HttpObjectDecoder
in the pipeline
so that this handler can intercept HTTP requests after HttpObjectDecoder
converts ByteBuf
s into HTTP requests.
ChannelHandler.Sharable
Modifier and Type | Field and Description |
---|---|
protected ChannelHandlerContext |
ctx |
Constructor and Description |
---|
HttpContentDecoder() |
Modifier and Type | Method and Description |
---|---|
void |
channelInactive(ChannelHandlerContext ctx)
Calls
ChannelHandlerContext.fireChannelInactive() 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 void |
decode(ChannelHandlerContext ctx,
HttpObject msg,
List<Object> out)
Decode from one message to an other.
|
protected String |
getTargetContentEncoding(String contentEncoding)
Returns the expected content encoding of the decoded content.
|
void |
handlerAdded(ChannelHandlerContext ctx)
Do nothing by default, sub-classes may override this method.
|
void |
handlerRemoved(ChannelHandlerContext ctx)
Do nothing by default, sub-classes may override this method.
|
protected abstract EmbeddedChannel |
newContentDecoder(String contentEncoding)
Returns a new
EmbeddedChannel that decodes the HTTP message
content encoded in the specified contentEncoding. |
acceptInboundMessage, channelRead
channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught, userEventTriggered
ensureNotSharable, isSharable
protected ChannelHandlerContext ctx
protected void decode(ChannelHandlerContext ctx, HttpObject msg, List<Object> out) throws Exception
MessageToMessageDecoder
decode
in class MessageToMessageDecoder<HttpObject>
ctx
- the ChannelHandlerContext
which this MessageToMessageDecoder
belongs tomsg
- the message to decode to an other oneout
- the List
to which decoded messages should be addedException
- is thrown if an error occurspublic void channelReadComplete(ChannelHandlerContext ctx) throws Exception
ChannelInboundHandlerAdapter
ChannelHandlerContext.fireChannelReadComplete()
to forward
to the next ChannelInboundHandler
in the ChannelPipeline
.
Sub-classes may override this method to change behavior.channelReadComplete
in interface ChannelInboundHandler
channelReadComplete
in class ChannelInboundHandlerAdapter
Exception
protected abstract EmbeddedChannel newContentDecoder(String contentEncoding) throws Exception
EmbeddedChannel
that decodes the HTTP message
content encoded in the specified contentEncoding.contentEncoding
- the value of the "Content-Encoding"
headerEmbeddedChannel
if the specified encoding is supported.
null
otherwise (alternatively, you can throw an exception
to block unknown encoding).Exception
protected String getTargetContentEncoding(String contentEncoding) throws Exception
"identity"
by default, which is the case for
most decoders.contentEncoding
- the value of the "Content-Encoding"
headerException
public void handlerRemoved(ChannelHandlerContext ctx) throws Exception
ChannelHandlerAdapter
handlerRemoved
in interface ChannelHandler
handlerRemoved
in class ChannelHandlerAdapter
Exception
public void channelInactive(ChannelHandlerContext ctx) throws Exception
ChannelInboundHandlerAdapter
ChannelHandlerContext.fireChannelInactive()
to forward
to the next ChannelInboundHandler
in the ChannelPipeline
.
Sub-classes may override this method to change behavior.channelInactive
in interface ChannelInboundHandler
channelInactive
in class ChannelInboundHandlerAdapter
Exception
public void handlerAdded(ChannelHandlerContext ctx) throws Exception
ChannelHandlerAdapter
handlerAdded
in interface ChannelHandler
handlerAdded
in class ChannelHandlerAdapter
Exception
Copyright © 2008–2024 The Netty Project. All rights reserved.