在Java内利用Socket实现在控制台进行实时聊天

朴灿烈づ我的快乐病毒、 2022-05-26 07:30 204阅读 0赞

本Demo是在CSDN的其他一篇关于Socket通信的Demo基础上，利用多线程实现了服务端与客户端的相互通信。

原Demo博客的地址https://blog.csdn.net/qiuyoungster/article/details/58030191

第一次在CSDN发博客，还有很多不懂的地方，望大佬们多多指点。

package com.lvjia.car.socket;
    
    import java.io.*;
    import java.net.ServerSocket;
    import java.net.Socket;
    import java.util.HashMap;
    import java.util.Map;
    import java.util.Scanner;
    
    public class Server {
        private ServerSocket serverSocket;
        private final Map socketMap=new HashMap();
        private final Map clientSizeMap=new HashMap();
    
    
        public Server(){
            try{
                serverSocket = new ServerSocket(8088);
            }catch(Exception e){
                e.printStackTrace();
            }
        }
    
        public void start(){
    
    
            try{
                Socket socket = null;
    
                new Thread(new Runnable() {
      //创建一条线程，向客户端发送消息
                    @Override
                    public void run() {
                        Scanner scanner = new Scanner(System.in);
                        while(true){
                            String demo=scanner.nextLine();
                            String[] demoArray=demo.split("/:");
                            String socketIp=demoArray[0];
                            String info=demoArray[1];
    
                            System.out.println("服务端输入的ip："+socketIp);
                            System.out.println("服务端发送的消息:"+info);
                            Socket socket=(Socket)socketMap.get(socketIp);
                            try{
                                OutputStream out = socket.getOutputStream();
                                //OutputStreamWriter osw = new OutputStreamWriter(out, true);
                                OutputStreamWriter osw = new OutputStreamWriter(out, "UTF-8");
                                PrintWriter pw = new PrintWriter(osw, true);
                                pw.println("你好！客户端！");
                                //创建Scanner读取用户输入内容
    
                                    //scan.nextLine();
                                    pw.println(info);
    
                            }catch(Exception e){
                                e.printStackTrace();
                            }
                        }
    
                    }
                }).start();
    
                //serverSocket.accept() 方法会产生阻塞，直到某个Socket连接，返回请求连接的Socket
                while ((socket = serverSocket.accept())!=null){
      //每当有新的客户端连接到服务器，便创建一条线程，获取连接到服务端的客户端，并将之socket保存在Map集合中
                    final  Socket socket1 = socket;
                    socketMap.put(socket1.getInetAddress().getHostAddress(),socket1);
                    System.out.println("===========================================");
                    System.out.println("有新的连接，新连接的客户端Ip："+socket1.getInetAddress().getHostAddress());
                    System.out.println("当前连接的客户端总数："+socketMap.size()+"条");
                    Integer clientsize=socketMap.size();
                    clientSizeMap.put(socket1.getInetAddress().getHostAddress(),clientsize);
    
                    new Thread(new Runnable() {
                        @Override
                        public void run() {
                            System.out.println("客户端"+clientsize+"已连接！");
                            System.out.println("===========================================");
                            try {
                                Integer number =(Integer) clientSizeMap.get(socket1.getInetAddress().getHostAddress());
                                InputStream in = socket1.getInputStream();
                                InputStreamReader isr = new InputStreamReader(in, "UTF-8");
                                BufferedReader br = new BufferedReader(isr);
                                //不断读取客户端数据
                                while(true){
                                    System.out.println("客户端"+number+"说：" + br.readLine());
                                }
                            }catch (Exception e){
                            }
    
                        }
                    }).start();
                }
    
    
            }catch(Exception e){
                e.printStackTrace();
            }
        }
    
        public static void main(String[] args) {
            // TODO Auto-generated method stub Server server = new Server();
            server.start();
        }
    }

package com.lvjia.car.socket;
    
    import java.io.*;
    import java.net.Socket;
    import java.util.HashMap;
    import java.util.Map;
    import java.util.Scanner;
    
    public class Client {
        private  Socket socket;
    
        public Client(){
            try {
                socket = new Socket("localhost", 8088);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
        public void start(){
            final  Socket socket1=this.socket;
            new Thread(new Runnable() {
      //创建一条线程，监听获取服务端发送的消息
                @Override
                public void run() {
                    try {
                        InputStream in = socket1.getInputStream();
                        InputStreamReader isr = new InputStreamReader(in, "UTF-8");
                        BufferedReader br = new BufferedReader(isr);
                        //System.out.println("客户端说：" + br.readLine());
                        //不断读取客户端数据
                        while(true){
                            System.out.println("服务端说：" + br.readLine());
                        }
                    }catch (Exception e){
                    }
                }
            }).start();
    
            try{
      //向服务端发送消息
                OutputStream out = socket.getOutputStream();
                //OutputStreamWriter osw = new OutputStreamWriter(out, true);
                OutputStreamWriter osw = new OutputStreamWriter(out, "UTF-8");
                PrintWriter pw = new PrintWriter(osw, true);
                pw.println("你好！服务器！");
                //创建Scanner读取用户输入内容
                Scanner scanner = new Scanner(System.in);
                while(true){
                    //scan.nextLine();
                    System.out.println("尊敬的用户，请您输入：");
                    pw.println(scanner.nextLine());
                }
            }catch(Exception e){
                e.printStackTrace();
            }finally{
                if(socket != null){
                    try{
                        socket.close();
                    }catch(Exception e){
                        e.printStackTrace();
                    }
                }
            }
    
        }
    
        public static void main(String[] args) {
            // TODO Auto-generated method stub Client client = new Client();
            client.start();
        }
    }

分为服务器端和客户端

注意：在启动时，先启动Server，再启动Client

不然会报    java.net.ConnectException: Connection refused: connect    异常.

==========================

启动后，Server控制台:

![70][]

Client控制台:

![70 1][]

==========================

在客户端，客户端向服务端发送消息时，直接输入想要发送的消息，然后回车，就ok

在服务端，服务端想某个客户端发送消息时，格式为:该客户端IP+/:Hello CSDN。例如：127.0.0.1/:Hello CSDN

![70 2][]

![70 3][]

第一次发稿，有很多不足，希望可以相互交流学习。

[70]: /images/20220526/ea59fd8fea604b0ba73f9748406aebc1.png
[70 1]: /images/20220526/d51c6723b1224d20a9bda6643790d2b6.png
[70 2]: /images/20220526/31ce822cde3e40dc8d081aa532b2a2a8.png
[70 3]: /images/20220526/9b18eaf91ae144e299e5065cde63b9b0.png