Client和Server双端通信（线程版）

import java.net.*;
import java.io.*;
import java.util.Scanner;

class server {
    public static void main(String[] args) {
        try {
            ServerSocket ss = new ServerSocket(4321);
            System.out.println("Server OK");
            while(true) {
                Socket s = ss.accept();
                serv p = new serv(s);
                Thread t = new Thread(p);
                t.start();
            }
        } catch(IOException E) {}
    }
}

class serv implements Runnable {
    Socket s;
    static int i;
    public serv(Socket s1) {
        s = s1;
    }
    public void run() {
        try {
            BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
            String info = in.readLine();
            ++i;
            System.out.println("info from client " + i);
            PrintStream out = new PrintStream(s.getOutputStream());
            out.println("You are number " + i);
            in.close();
            out.close();
            s.close();
        } catch (IOException e) {}
    }
}

class client {
    public static void main(String[] args) {
        try {
            Socket s = new Socket("127.0.0.1",4321);
            PrintStream out = new PrintStream(s.getOutputStream());
            String c = "ACM";
            out.println(c);
            BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
            String x = in.readLine();
            System.out.println("Info from Server: " + x);
            out.close();
            in.close();
            s.close();
        } catch(IOException e) {}
    }
}