netty中的传输

public void bio(int port) throws IOException{
        final ServerSocket socket = new ServerSocket(port);
        try {
            //死循环,直到有连接再用线程将内容写入
            while (true){
                Socket client = socket.accept();//阻塞
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        OutputStream out;
                        try {
                            out = client.getOutputStream();
                            out.write("hello world".getBytes(CharsetUtil.UTF_8));
                            out.flush();
                            client.close();
                        }catch (IOException e){
                            e.printStackTrace();
                        }finally {
                            try {
                                client.close();
                            }catch (IOException e){
                                e.printStackTrace();
                            }
                        }
                    }
                }).start();
            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }

public void serve(int port) throws IOException {
        ServerSocketChannel serverChannel = ServerSocketChannel.open();
        serverChannel.configureBlocking(false);//channel设置为非阻塞模式
        ServerSocket ss = serverChannel.socket();
        InetSocketAddress address = new InetSocketAddress(port);
        ss.bind(address);
        Selector selector = Selector.open();
        serverChannel.register(selector, SelectionKey.OP_ACCEPT);
        final ByteBuffer msg = ByteBuffer.wrap("Hi!\r\n".getBytes());
        for (;;){
            try {
                selector.select();//这个函数是阻塞的
            } catch (IOException ex) {
                ex.printStackTrace();
                //handle exception
                break;
            }
            Set readyKeys = selector.selectedKeys();
            Iterator iterator = readyKeys.iterator();
            while (iterator.hasNext()) {
                SelectionKey key = iterator.next();
                iterator.remove();
                try {
                    if (key.isAcceptable()) {
                        ServerSocketChannel server =
                                (ServerSocketChannel) key.channel();
                        SocketChannel client = server.accept();
                        client.configureBlocking(false);
                        client.register(selector, SelectionKey.OP_WRITE |
                                SelectionKey.OP_READ, msg.duplicate());//注册到selector中
                        System.out.println(
                                "Accepted connection from " + client);
                    }
                    if (key.isWritable()) {
                        SocketChannel client =
                                (SocketChannel) key.channel();
                        ByteBuffer buffer =
                                (ByteBuffer) key.attachment();
                        while (buffer.hasRemaining()) {
                            if (client.write(buffer) == 0) {
                                break;
                            }
                        }
                        client.close();
                    }
                } catch (IOException ex) {
                    key.cancel();
                    try {
                        key.channel().close();
                    } catch (IOException cex) {
                        // ignore on close
                    }
                }
            }
        }
    }