package UDPword;

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

public class test extends Thread{
public static void main(String[] args) throws IOException {
int port = 10000;
String name;
MulticastSocket ms = new MulticastSocket(port);

Scanner sc = new Scanner(System.in);
InetAddress address = InetAddress.getByName("224.0.1.0");
ms.joinGroup(address);

System.out.println("请输入网名");
name=sc.next();
System.out.println("----------------");
new Thread(() -> {
    while (true) {
        try {
            String txt = name+": "+sc.next();
            byte[] bytes = txt.getBytes();
            DatagramPacket dp = new DatagramPacket(bytes,bytes.length, address, port);
            ms.send(dp);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}).start();

new Thread(() -> {
    while (true){
        byte[] bytes = new byte[1024];
        try {
            DatagramPacket dp =new DatagramPacket(bytes,bytes.length);
            ms.receive(dp);

            byte[] data = dp.getData();
            int length = dp.getLength();

            String b = new String(data,0,length);

            System.out.println(b);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}).start();

}
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}