Java中使用ServerSocket和Socket的多线程示例

Posted 2022-01-08

开始...
1、服务器端：

public class ServerSocketApp 
    public static void main(String[] args) 
        try 
            ServerSocket serverSocket = new ServerSocket(9999);
            System.out.println("服务已启动");
            while (true) 
                Socket socket = serverSocket.accept();
                System.out.println("客户" + socket.getInetAddress().getHostAddress() + "来访，");
                new Thread(() -> 
                    try 
                        InputStream inputStream = socket.getInputStream();
                        PrintStream printStream = new PrintStream(socket.getOutputStream());
                        Scanner in = new Scanner(inputStream);
                        in.useDelimiter("\n");
                        while (in.hasNext()) 
                            String message = in.next().trim();
                            if (message.equalsIgnoreCase("bye")) 
                                String bye = new String("客户端已退出，拜拜".getBytes("UTF-8"));
                                System.out.println(bye);
                                printStream.println(bye);
                             else 
                                printStream.println("ECHO>" + message);
                            
                        
                     catch (IOException e) 
                        e.printStackTrace();
                    
                ).start();
            
         catch (IOException e) 
            e.printStackTrace();
        
    

2、客户端程序：

public class ClientSocketApp 
    public static void main(String[] args) throws IOException 
        Socket socket = new Socket("localhost", 9999);
        Scanner in = new Scanner(System.in);
        Scanner inputStream = new Scanner(socket.getInputStream());
        PrintStream printStream = new PrintStream(socket.getOutputStream());
        in.useDelimiter("\n");
        inputStream.useDelimiter("\n");
        boolean b = true;
        System.out.println("请输入：");
        while (b) 
            if (in.hasNext()) 
                String message = in.next().trim();
                printStream.println(message);
                if (inputStream.hasNext()) 
                    String serverMessage = new String(inputStream.next().trim().getBytes("UTF-8"));
                    System.out.println(serverMessage);
                
                if (message.equalsIgnoreCase("bye")) 
                    b = false;
                
            
        
        socket.close();
    

3、运行
服务器
cd com/kyy/bases/socket 运行javac ServerSocketApp.java
cd classpath根目录 运行java ServerSocketApp
服务器端启动
客户端
cd com/kyy/bases/socket 运行javac ClientSocketApp.java
cd classpath根目录 运行java ClientSocketApp

遇到的问题：
如果不通过eclipse、Idea等工具，会出现 “找不到或无法加载主类 com.kyy.bases.socket.ClientSocketApp”的异常
解决办法，设置classpath=.;"JAVA_HOME"/lib
或者在cmd窗口临时设置set classpath=.;

...结束