io.netty.handler.codec.http

Class HttpContentEncoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.ChannelDuplexHandler

io.netty.handler.codec.MessageToMessageCodec<HttpRequest,HttpObject>

io.netty.handler.codec.http.HttpContentEncoder

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler, ChannelOutboundHandler

Direct Known Subclasses:

HttpContentCompressor

public abstract class HttpContentEncoder
extends MessageToMessageCodec<HttpRequest,HttpObject>

Encodes the content of the outbound HttpResponse and HttpContent. The original content is replaced with the new content encoded by the EmbeddedChannel, which is created by beginEncode(HttpResponse, String). Once encoding is finished, the value of the 'Content-Encoding' header is set to the target content encoding, as returned by beginEncode(HttpResponse, String). Also, the 'Content-Length' header is updated to the length of the encoded content. If there is no supported or allowed encoding in the corresponding HttpRequest's "Accept-Encoding" header, beginEncode(HttpResponse, String) should return null so that no encoding occurs (i.e. pass-through).

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

This handler must be placed after HttpObjectEncoder in the pipeline so that this handler can intercept HTTP responses before HttpObjectEncoder converts them into ByteBufs.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	HttpContentEncoder.Result

Nested classes/interfaces inherited from interface io.netty.channel.ChannelHandler

ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor and Description
HttpContentEncoder()

Method Summary

Modifier and Type	Method and Description
boolean	acceptOutboundMessage(Object msg) Returns true if and only if the specified message can be encoded by this codec.
protected abstract HttpContentEncoder.Result	beginEncode(HttpResponse headers, String acceptEncoding) Prepare to encode the HTTP message content.
void	channelInactive(ChannelHandlerContext ctx) Calls ChannelHandlerContext.fireChannelInactive() to forward to the next ChannelInboundHandler in the ChannelPipeline.
protected void	decode(ChannelHandlerContext ctx, HttpRequest msg, List<Object> out)
protected void	encode(ChannelHandlerContext ctx, HttpObject msg, List<Object> out)
void	handlerRemoved(ChannelHandlerContext ctx) Do nothing by default, sub-classes may override this method.

Methods inherited from class io.netty.handler.codec.MessageToMessageCodec

acceptInboundMessage, channelRead, write

Methods inherited from class io.netty.channel.ChannelDuplexHandler

bind, close, connect, deregister, disconnect, flush, read

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelReadComplete, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught, userEventTriggered

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, handlerAdded, isSharable

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.netty.channel.ChannelHandler

exceptionCaught, handlerAdded

Constructor Detail

HttpContentEncoder

public HttpContentEncoder()

Method Detail

acceptOutboundMessage

public boolean acceptOutboundMessage(Object msg)
                              throws Exception

Description copied from class: MessageToMessageCodec

Returns true if and only if the specified message can be encoded by this codec.

Overrides:

acceptOutboundMessage in class MessageToMessageCodec<HttpRequest,HttpObject>

Parameters:

msg - the message

Throws:

Exception

decode

protected void decode(ChannelHandlerContext ctx,
                      HttpRequest msg,
                      List<Object> out)
               throws Exception

Specified by:

decode in class MessageToMessageCodec<HttpRequest,HttpObject>

Throws:

Exception

See Also:

MessageToMessageDecoder.decode(ChannelHandlerContext, Object, List)

encode

protected void encode(ChannelHandlerContext ctx,
                      HttpObject msg,
                      List<Object> out)
               throws Exception

Specified by:

encode in class MessageToMessageCodec<HttpRequest,HttpObject>

Throws:

Exception

See Also:

MessageToMessageEncoder.encode(ChannelHandlerContext, Object, List)

beginEncode

protected abstract HttpContentEncoder.Result beginEncode(HttpResponse headers,
                                                         String acceptEncoding)
                                                  throws Exception

Prepare to encode the HTTP message content.

Parameters:

headers - the headers

acceptEncoding - the value of the "Accept-Encoding" header

Returns:

the result of preparation, which is composed of the determined target content encoding and a new EmbeddedChannel that encodes the content into the target content encoding. null if acceptEncoding is unsupported or rejected and thus the content should be handled as-is (i.e. no encoding).

Throws:

Exception

handlerRemoved

public void handlerRemoved(ChannelHandlerContext ctx)
                    throws Exception

Description copied from class: ChannelHandlerAdapter

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

Specified by:

handlerRemoved in interface ChannelHandler

Overrides:

handlerRemoved in class ChannelHandlerAdapter

Throws:

Exception

channelInactive

public void channelInactive(ChannelHandlerContext ctx)
                     throws Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelInactive() to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelInactive in interface ChannelInboundHandler

Overrides:

channelInactive in class ChannelInboundHandlerAdapter

Throws:

Exception