java UDP广播与接收(服务端与客户端)

package com.ilike.udp; import java.net.DatagramPacket; import java.net.InetAddress; import java.net.MulticastSocket; public class UdpBroadCast { // private static String ip="114.113.33.205"; // 服务端ip //端口 private static int BROADCAST_PORT = 9899; //组ip private static String BROADCAST_IP = "224.0.0.1"; //组 static InetAddress inetAddress = null; //多组数据报套接字 static MulticastSocket multicastSocket = null; public static void main(String[] args) { try { //创建组 inetAddress = InetAddress.getByName(BROADCAST_IP); //创建服务器 multicastSocket = new MulticastSocket(BROADCAST_PORT); //当参数为0时，指定数据报停留在本地主机，为1时，指定数据报发送到本地局域网网，为32时，发送到本站点的网络上。为64时，发送到本地区，128时，发送到本大洲，255为全球。 multicastSocket.setTimeToLive(1); //加入组 multicastSocket.joinGroup(inetAddress); } catch (Exception e) { e.printStackTrace(); } new Thread(new Runnable() { @Override public void run() { //创建数据传输对象 DatagramPacket dataPacket = null; //被传输的数据 byte[] data ="hello".getBytes(); dataPacket = new DatagramPacket(data, data.length, inetAddress,BROADCAST_PORT); while(true){ try{ //发送 multicastSocket.send(dataPacket); Thread.sleep(3000); System.out.println("再次发送ip地址广播:....."); } catch (Exception e){ e.printStackTrace(); } } } }).start(); } }