public abstract class HttpContentDecoder extends SimpleChannelUpstreamHandler implements LifeCycleAwareChannelHandler
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 ChannelBuffer
s into HTTP requests.
ChannelHandler.Sharable
Modifier | Constructor and Description |
---|---|
protected |
HttpContentDecoder()
Creates a new instance.
|
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. |
protected String |
getTargetContentEncoding(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(String contentEncoding)
Returns a new
DecoderEmbedder that decodes the HTTP message
content encoded in the specified contentEncoding. |
channelBound, channelConnected, channelDisconnected, channelInterestChanged, channelOpen, channelUnbound, childChannelClosed, childChannelOpen, exceptionCaught, handleUpstream, writeComplete
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception
SimpleChannelUpstreamHandler
ChannelBuffer
) was received
from a remote peer.messageReceived
in class SimpleChannelUpstreamHandler
Exception
public void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception
SimpleChannelUpstreamHandler
Channel
was closed and all its related resources
were released.channelClosed
in class SimpleChannelUpstreamHandler
Exception
protected abstract DecoderEmbedder<ChannelBuffer> newContentDecoder(String contentEncoding) throws Exception
DecoderEmbedder
that decodes the HTTP message
content encoded in the specified contentEncoding.contentEncoding
- the value of the "Content-Encoding"
headerDecoderEmbedder
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 beforeAdd(ChannelHandlerContext ctx) throws Exception
beforeAdd
in interface LifeCycleAwareChannelHandler
Exception
public void afterAdd(ChannelHandlerContext ctx) throws Exception
afterAdd
in interface LifeCycleAwareChannelHandler
Exception
public void beforeRemove(ChannelHandlerContext ctx) throws Exception
beforeRemove
in interface LifeCycleAwareChannelHandler
Exception
public void afterRemove(ChannelHandlerContext ctx) throws Exception
afterRemove
in interface LifeCycleAwareChannelHandler
Exception
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