java使用MulticastSocket实现组播

import java.net.DatagramPacket;
import java.net.InetAddress;
import java.net.MulticastSocket;
 
public class Sender {
 
 public static void main(String[] args) {
 try {
  byte[] msg = new byte[] { 'h', 'e', 'l', 'l', 'o' };
  InetAddress inetAddress = InetAddress.getByName("230.0.0.1");//根据主机名返回主机的IP地址
  DatagramPacket datagramPacket = new DatagramPacket(msg, msg.length, inetAddress, 7777);//数据包包含消息内容，消息长度，组播IP和端口
  MulticastSocket multicastSocket = new MulticastSocket();
  multicastSocket.send(datagramPacket);//发送数据包
 } catch (Exception exception) {
  exception.printStackTrace();
 }
 }
}

import java.net.DatagramPacket;
import java.net.InetAddress;
import java.net.MulticastSocket;
 
public class Receiver {
 public static void main(String[] arstring) {
 try {
  MulticastSocket multicastSocket = new MulticastSocket(7777);//创建组播套接字并绑定到发送端口
  InetAddress inetAddress = InetAddress.getByName("230.0.0.1");
  multicastSocket.joinGroup(inetAddress);//组播套接字加入组播组
  
  while (true) {
  byte[] data = new byte[100];
  DatagramPacket datagramPacket = new DatagramPacket(data,data.length);//创建一个用于接收数据的数据包
  multicastSocket.receive(datagramPacket);//接收数据包
  System.out.println(new String(data));
  }
 } catch (Exception exception) {
  exception.printStackTrace();
 }
 }
}