Package io.netty.handler.codec.http

Class HttpContentEncoder

  • All Implemented Interfaces:
    io.netty.channel.ChannelHandler, io.netty.channel.ChannelInboundHandler, io.netty.channel.ChannelOutboundHandler
    Direct Known Subclasses:
    HttpContentCompressor
    public abstract class HttpContentEncoder
extends io.netty.handler.codec.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 Description
      static class  HttpContentEncoder.Result  

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

        io.netty.channel.ChannelHandler.Sharable

    • Method Summary

      All Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      boolean acceptOutboundMessage​(Object msg)  
      protected abstract HttpContentEncoder.Result beginEncode​(HttpResponse httpResponse, String acceptEncoding)
      Prepare to encode the HTTP message content.
      void channelInactive​(io.netty.channel.ChannelHandlerContext ctx)  
      protected void decode​(io.netty.channel.ChannelHandlerContext ctx, HttpRequest msg, List<Object> out)  
      protected void encode​(io.netty.channel.ChannelHandlerContext ctx, HttpObject msg, List<Object> out)  
      void handlerRemoved​(io.netty.channel.ChannelHandlerContext ctx)  

      • 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 interface io.netty.channel.ChannelHandler

        handlerAdded

    • Constructor Detail

      • HttpContentEncoder

        public HttpContentEncoder()

    • Method Detail

      • acceptOutboundMessage

        public boolean acceptOutboundMessage​(Object msg)
                              throws Exception
        Overrides:
        acceptOutboundMessage in class io.netty.handler.codec.MessageToMessageCodec<HttpRequest,​HttpObject>
        Throws:
        Exception

      • beginEncode

        protected abstract HttpContentEncoder.Result beginEncode​(HttpResponse httpResponse,
                                                         String acceptEncoding)
                                                  throws Exception
        Prepare to encode the HTTP message content.
        Parameters:
        httpResponse - the http response
        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​(io.netty.channel.ChannelHandlerContext ctx)
                    throws Exception
        Specified by:
        handlerRemoved in interface io.netty.channel.ChannelHandler
        Overrides:
        handlerRemoved in class io.netty.channel.ChannelHandlerAdapter
        Throws:
        Exception

      • channelInactive

        public void channelInactive​(io.netty.channel.ChannelHandlerContext ctx)
                     throws Exception
        Specified by:
        channelInactive in interface io.netty.channel.ChannelInboundHandler
        Overrides:
        channelInactive in class io.netty.channel.ChannelInboundHandlerAdapter
        Throws:
        Exception