一个简单的Socket通信例子

叁歲伎倆 2023-06-27 06:17 23阅读 0赞

### 客户端与服务端交互流程 ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ_size_16_color_FFFFFF_t_70][]

### 客户端 ###

public class Client { 
        // 服务端 host
        private static final String HOST = "127.0.0.1";
        // 服务端 port
        private static final int PORT = 8000;
        // 消息发送间隔
        private static final int SLEEP_TIME = 5000;
    
        public static void main(String[] args) throws IOException { 
            // 创建客户端socket
            final Socket socket = new Socket(HOST, PORT);
    
            new Thread(() -> { 
                System.out.println("客户端启动成功!");
                while (true) { 
                    try { 
                        String message = "hello world";
                        System.out.println("客户端发送数据: " + message);
                        socket.getOutputStream().write(message.getBytes());
                    } catch (Exception e) { 
                        System.out.println("写数据出错!");
                    }
                    // 睡眠一段时间再发送消息
                    sleep();
                }
            }).start();
        }
    
        private static void sleep() { 
            try { 
                Thread.sleep(SLEEP_TIME);
            } catch (InterruptedException e) { 
                e.printStackTrace();
            }
        }
    }

### 服务端 ###

public class Server { 
    
        private ServerSocket serverSocket;
    
        public Server(int port) { 
            try { 
                // 创建服务端 socket 对象
                this.serverSocket = new ServerSocket(port);
                System.out.println("服务端启动成功！端口:" + port);
            } catch (IOException e) { 
                e.printStackTrace();
            }
    
        }
    
        public void start() { 
            // 新建子线程处理请求（不阻塞主线程）
            new Thread(() -> doStart()).start();
        }
    
        private void doStart() { 
            while (true) { 
                try { 
                    // 监听消息，没有消息时会阻塞
                    Socket client = serverSocket.accept();
                    // 消息处理
                    new ClientHandler(client).start();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
        }
    }

#### 服务端处理消息的逻辑 ####

public class ClientHandler { 
    
        private static final int MAX_DATA_LEN = 1024;
    
        private Socket socket;
    
        public ClientHandler(Socket socket) { 
            this.socket = socket;
        }
    
        public void start() { 
            System.out.println("新客户端接入");
            // 创建子线程接收新客户端的消息
            new Thread(()-> doStart()).start();
        }
    
        private void doStart() { 
            try { 
                // 读取消息流
                InputStream inputStream = socket.getInputStream();
                while (true) { 
                    byte[] data = new byte[MAX_DATA_LEN];
                    int len;
                    while((len = inputStream.read(data)) != -1) { 
                        String message = new String(data, 0, len);
                        System.out.println("客户端传来的消息：" + message);
                        // 将数据回传客户端
                        socket.getOutputStream().write(data);
                    }
                }
            } catch (IOException e) { 
                e.printStackTrace();
            }
    
        }
    }

#### 服务端启动逻辑 ####

public class ServerBoot { 
        private static final int PORT = 8000;
    
        public static void main(String[] args) { 
            Server server = new Server(PORT);
            server.start();
        }
    }

### 结果验证 ###

先启动服务端，再启动客户端，在控制台上可以看到打印的结果。  
服务端控制台：  
![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ_size_16_color_FFFFFF_t_70 1][]  
客户端控制台：  
![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ_size_16_color_FFFFFF_t_70 2][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200104174843674.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ=,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20200104173123912.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ=,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ_size_16_color_FFFFFF_t_70 2]: https://img-blog.csdnimg.cn/2020010417393317.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEyMTIzOTQ=,size_16,color_FFFFFF,t_70