背景

作为网络传输框架，免不了传输对象，对象在传输之前就要序列化，这个序列化的过程就是编码过程。接收到编码后的数据就需要解码，还原传输的数据。

编解码技术就是java序列化技术，序列化的目的有两个，一是进行网络传输，二是对象持久化。

但是Java的序列化缺点很多，如无法跨语言，序列化后码流太大，序列化性能太低

主流的序列化框架：

JBoss Marshalling的实现

代码示例：

public class Server {

    public static void main(String[] args) throws Exception {

        EventLoopGroup pGroup = new NioEventLoopGroup();
        EventLoopGroup cGroup = new NioEventLoopGroup();

        ServerBootstrap b = new ServerBootstrap();
        b.group(pGroup, cGroup).channel(NioServerSocketChannel.class).option(ChannelOption.SO_BACKLOG, 1024)
                // 设置日志
                .handler(new LoggingHandler(LogLevel.INFO)).childHandler(new ChannelInitializer<SocketChannel>() {
                    protected void initChannel(SocketChannel sc) throws Exception {
                        sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingDecoder());
                        sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingEncoder());
                        sc.pipeline().addLast(new ServerHandler());
                    }
                });

        ChannelFuture cf = b.bind(8765).sync();

        cf.channel().closeFuture().sync();
        pGroup.shutdownGracefully();
        cGroup.shutdownGracefully();

    }
}

public class ServerHandler extends ChannelHandlerAdapter {

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {

    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        Req req = (Req) msg;
        System.out.println("Server : " + req.getId() + ", " + req.getName() + ", " + req.getRequestMessage());
        byte[] attachment = GzipUtils.ungzip(req.getAttachment());

        String path = System.getProperty("user.dir") + File.separatorChar + "receive" + File.separatorChar + "001.jpg";
        FileOutputStream fos = new FileOutputStream(path);
        fos.write(attachment);
        fos.close();

        Resp resp = new Resp();
        resp.setId(req.getId());
        resp.setName("resp" + req.getId());
        resp.setResponseMessage("响应内容" + req.getId());
        ctx.writeAndFlush(resp);// .addListener(ChannelFutureListener.CLOSE);
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {

    }