• Socket聊天服务器任务：ChatServer类负责开启Server端服务；ReceiveMsg负责接收消息；SendMsg负责发送消息；Server端响应请求，向Client端返回数据。

public class ChatServer extends Thread {
        private ChatServer() throws IOException {
            //创建Socket服务
            CreateSocket();
        }

        public void run() {
            Socket client;
            //定义接收的文本
            String txt;
            try {
                //始终在监听
                while (true) {
                    //开启线程实时监听socket端口
                    //获取应答消息
                    client = ResponseSocket();
                    //响应客户端连接请求
                    while (true) {
                        //接受客户端消息
                        txt = ReceiveMsg(client);
                        //连接获得客户端发来消息
                        //并将其显示在Server端屏幕上
                        SendMsg(client, txt);
                        //向客户端返回消息
                        if (true) {
                            break;
                        }
                        //中断，继续等待连接请求
                    }
                    //关闭此次连接
                    CloseSocket(client);
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        //定义一个ServerSocket对象
        private ServerSocket server = null;
        //定义端口
        private static final int PORT = 5000;
        //定义写buffer
        private BufferedWriter writer;
        //定义读buffer
        private BufferedReader reader;

        //实例化ServerSocket
        private void CreateSocket() throws IOException {
            server = new ServerSocket(PORT, 100);
        }

        //接收消息
        private Socket ResponseSocket() throws IOException {
            Socket client = server.accept();
            return client;
        }

        //关闭打开的连接和缓存
        private void CloseSocket(Socket socket) throws IOException {
            reader.close();
            writer.close();
            socket.close();
        }

        //封装发送消息的方法
        private void SendMsg(Socket socket, String Msg) throws IOException {
            //要发送的消息写入BufferedWriter中
            writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
            //添加空行分隔符
            writer.write(Msg + "\n");
            //刷新，发送
            writer.flush();
        }

        //接收消息的方法
        private String ReceiveMsg(Socket socket) throws IOException {
            //保存到读buffer
            reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            //将接收到的信息保存到字符串中
            String txt = "Server send:" + reader.readLine();
            return txt;
        }
    }

启动服务器的代码如下

ChatServer chatServer = null;
                try {
                    chatServer = new ChatServer();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                //检测服务器是否已经起动，如果没有则启动服务器
                if(chatServer != null){
                    chatServer.start();
                }

客户端的任务：客户端发起连接请求，并向服务器发送数据；客户端接收服务器的数据。

//客户端获取消息类
private Socket RequestSocket(String host, int port) throws UnknownHostException, IOException {
    Socket socket = new Socket(host, port);
    return socket;
}

//客户端发送消息类
private void SendMsg(Socket socket, String msg) throws IOException {
    //要发送的消息写入BufferedWriter中
    BufferedWriter wirter = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
    //格式转换
    wirter.write(msg.replace("\n", "  ") + "\n");
    //刷新，发送
    wirter.flush();
}

//客户端接收消息类
private String ReceiveMsg(Socket socket) throws IOException {
    //写入读buffer
    BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    //将信息保存到字符串中
    String txt = reader.readLine();
    return txt;
}