netty解决tcp粘包拆包问题

tcp粘包拆包解决方案

1.发送定长的消息

server端：

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

		ServerBootstrap b = new ServerBootstrap();
		b.group(pGroup, cGroup)
		 .channel(NioServerSocketChannel.class)
		 .childHandler(new ChannelInitializer<SocketChannel>() {
			@Override
			protected void initChannel(SocketChannel sc) throws Exception {
				//设置定长字符串接收
				sc.pipeline().addLast(new FixedLengthFrameDecoder(5));
				//设置字符串形式的解码
				sc.pipeline().addLast(new StringDecoder());
				sc.pipeline().addLast(new ServerHandler());
			}
		});

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

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

client：

EventLoopGroup group = new NioEventLoopGroup();

		Bootstrap b = new Bootstrap();
		b.group(group)
		 .channel(NioSocketChannel.class)
		 .handler(new ChannelInitializer<SocketChannel>() {
			@Override
			protected void initChannel(SocketChannel sc) throws Exception {
				sc.pipeline().addLast(new FixedLengthFrameDecoder(5));
				sc.pipeline().addLast(new StringDecoder());
				sc.pipeline().addLast(new ClientHandler());
			}
		});

		ChannelFuture cf = b.connect("127.0.0.1", 8765).sync();

		cf.channel().writeAndFlush(Unpooled.wrappedBuffer("111111112222222".getBytes()));
		cf.channel().writeAndFlush(Unpooled.copiedBuffer("3333333".getBytes()));

		cf.channel().closeFuture().sync();
		group.shutdownGracefully();

2.采用特殊分割符来进行分割

server端：

          
        EventLoopGroup pGroup = new NioEventLoopGroup();
		EventLoopGroup cGroup = new NioEventLoopGroup();
		ServerBootstrap b = new ServerBootstrap();
		b.group(pGroup, cGroup)
		 .channel(NioServerSocketChannel.class)
		 .option(ChannelOption.SO_BACKLOG, 1024)
		 .option(ChannelOption.SO_SNDBUF, 32*1024)
		 .option(ChannelOption.SO_RCVBUF, 32*1024)
		 .childHandler(new ChannelInitializer<SocketChannel>() {
			@Override
			protected void initChannel(SocketChannel sc) throws Exception {
				//设置特殊分隔符
				ByteBuf buf = Unpooled.copiedBuffer("$_".getBytes());
				sc.pipeline().addLast(new DelimiterBasedFrameDecoder(1024, buf));
				//设置字符串形式的解码
				sc.pipeline().addLast(new StringDecoder());
				sc.pipeline().addLast(new ServerHandler());
			}
		});

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

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

client：

                EventLoopGroup group = new NioEventLoopGroup();

		Bootstrap b = new Bootstrap();
		b.group(group)
		 .channel(NioSocketChannel.class)
		 .handler(new ChannelInitializer<SocketChannel>() {
			@Override
			protected void initChannel(SocketChannel sc) throws Exception {
				//$_作为分割符号
				ByteBuf buf = Unpooled.copiedBuffer("$_".getBytes());
				sc.pipeline().addLast(new DelimiterBasedFrameDecoder(1024, buf));
				sc.pipeline().addLast(new StringDecoder());
				sc.pipeline().addLast(new ClientHandler());
			}
		});

		ChannelFuture cf = b.connect("127.0.0.1", 8765).sync();

		cf.channel().writeAndFlush(Unpooled.wrappedBuffer("111111111$_".getBytes()));
		cf.channel().writeAndFlush(Unpooled.wrappedBuffer("222$_".getBytes()));

		//等待客户端端口关闭
		cf.channel().closeFuture().sync();
		group.shutdownGracefully();

采用自定义协议方式