MessageToMessageCodec

• MessageToMessageCodec
  • Decoder&Encoder
  • usage
  • demo

Decoder&Encoder

• MessageToMessageDecoder
• MessageToMessageEncoder

通过下面二个类的相关的功能，分析MessageToMessageCodec的用法

• StringDecoder
• StringEncoder

usage

StringDecoder,StringEncoder 可以再 netty 中进行基于String类型的数据通信

• StringDecoder 把ByteBuf转化为String,把接受到的 byte 字节，转化为 String
• StringEncoder 把String转化为ByteBuf,把String转化为byte字节，进行网络的传输

demo

Decodes a received ByteBuf into a String. Please note that this decoder must be used with a proper ByteToMessageDecoder such as DelimiterBasedFrameDecoder or LineBasedFrameDecoder if you are using a stream-based transport such as TCP/IP. A typical setup for a text-based line protocol in a TCP/IP socket would be:

ChannelPipeline pipeline = ...;
// Decoders
pipeline.addLast("frameDecoder", new LineBasedFrameDecoder(80));
pipeline.addLast("stringDecoder", new StringDecoder(CharsetUtil.UTF_8));

// Encoder
pipeline.addLast("stringEncoder", new StringEncoder(CharsetUtil.UTF_8));

// and then you can use a String instead of a ByteBuf as a message:
void channelRead(ChannelHandlerContext ctx, String msg) {
     ch.write("Did you say '" + msg + "'?\n");
}