public class TcpServer{

 public static void main(String[] args) throws IOException{
   IoAcceptor acceptor = new NioSocketAcceptor();

   // 添加一个Filter，用于接收、发送的内容按照"\r\n"分割
   acceptor.getFilterChain().addLast("codec",
       new ProtocolCodecFilter(new TextLineCodecFactory(Charset.forName("UTF-8"), "\r\n", "\r\n")));

   acceptor.setHandler(new TcpServerHandle());
   acceptor.bind(new InetSocketAddress(8080));
 }

}

class TcpServerHandle extends IoHandlerAdapter{

 @Override
 public void exceptionCaught(IoSession session, Throwable cause)
     throws Exception{
   cause.printStackTrace();
 }

 // 接收到新的数据
 @Override
 public void messageReceived(IoSession session, Object message)
     throws Exception{

   // 接收客户端的数据，这里接收到的不再是IoBuffer类型，而是字符串
   String line = (String) message;
   System.out.println("messageReceived:" + line);

 }

 @Override
 public void sessionCreated(IoSession session) throws Exception{
   System.out.println("sessionCreated");
 }

 @Override
 public void sessionClosed(IoSession session) throws Exception{
   System.out.println("sessionClosed");
 }
}

public class TcpServer{

 public static void main(String[] args) throws InterruptedException{
   EventLoopGroup bossGroup = new NioEventLoopGroup();
   EventLoopGroup workerGroup = new NioEventLoopGroup();
   try {
     ServerBootstrap b = new ServerBootstrap();
     b.group(bossGroup, workerGroup)
         .channel(NioServerSocketChannel.class)
         .childHandler(new ChannelInitializer() {
           @Override
           public void initChannel(SocketChannel ch)
               throws Exception{
             ChannelPipeline pipeline = ch.pipeline();

             // LineBasedFrameDecoder按行分割消息
             pipeline.addLast(new LineBasedFrameDecoder(80));
             // 再按UTF-8编码转成字符串
             pipeline.addLast(new StringDecoder(CharsetUtil.UTF_8));

             pipeline.addLast(new TcpServerHandler());
           }
         });
     ChannelFuture f = b.bind(8080).sync();
     f.channel().closeFuture().sync();
   } finally {
     workerGroup.shutdownGracefully();
     bossGroup.shutdownGracefully();
   }
 }

}

class TcpServerHandler extends ChannelInboundHandlerAdapter{

 // 接收到新的数据
 @Override
 public void channelRead(ChannelHandlerContext ctx, Object msg){

   // msg经过StringDecoder后类型不再是ByteBuf而是String
   String line = (String) msg;
   System.out.println("channelRead:" + line);
 }

 @Override
 public void channelActive(ChannelHandlerContext ctx){
   System.out.println("channelActive");
 }

 @Override
 public void channelInactive(ChannelHandlerContext ctx){
   System.out.println("channelInactive");
 }

 @Override
 public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause){
   cause.printStackTrace();
   ctx.close();
 }
}

# -*- coding:utf-8 –*-

from twisted.protocols.basic import LineOnlyReceiver
from twisted.internet.protocol import Factory
from twisted.internet import reactor

class TcpServerHandle(LineOnlyReceiver):

   # 新的连接建立
   def connectionMade(self):
       print 'connectionMade'

   # 连接断开
   def connectionLost(self, reason):
       print 'connectionLost'

   # 接收到新的一行数据
   def lineReceived(self, data):
       print 'lineReceived:' + data

factory = Factory()
factory.protocol = TcpServerHandle
reactor.listenTCP(8080, factory)
reactor.run()

public class TcpClient{

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

   Socket socket = null;
   OutputStream out = null;

   try {

     socket = new Socket("localhost", 8080);
     out = socket.getOutputStream();

     // 请求服务器
     String lines = "床前明月光\r\n疑是地上霜\r\n举头望明月\r\n低头思故乡\r\n";
     byte[] outputBytes = lines.getBytes("UTF-8");
     out.write(outputBytes);
     out.flush();

   } finally {
     // 关闭连接
     out.close();
     socket.close();
   }

 }

}

sessionCreated

messageReceived:床前明月光

messageReceived:疑是地上霜

messageReceived:举头望明月

messageReceived:低头思故乡

sessionClosed

channelActive

channelRead:床前明月光

channelRead:疑是地上霜

channelRead:举头望明月

channelRead:低头思故乡

channelInactive

connectionMade

lineReceived:床前明月光

lineReceived:疑是地上霜

lineReceived:举头望明月

lineReceived:低头思故乡

connectionLost