UDP消息发送

package com.wuming.lesson03;import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;//还是要等待客户端的连接
public class UdpServerDemo01 {public static void main(String[] args) throws Exception {//1.开放端口DatagramSocket socket = new DatagramSocket(9090);//接受数据包byte[] buffer = new byte[1024];DatagramPacket packet = new DatagramPacket(buffer, 0, buffer.length);socket.receive(packet);//阻塞接受System.out.println(packet.getAddress().getHostAddress());System.out.println(new String(packet.getData(),0,packet.getLength()));//关闭连接socket.close();}
}

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package com.wuming.lesson03;import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
//不需要连接服务器
public class UdpClientDemo01 {public static void main(String[] args) throws Exception {//1.建立一个socketDatagramSocket socket = new DatagramSocket();//2.建个包String msg="你好服务器";InetAddress localhost = InetAddress.getByName("localhost");int port= 9090;//数据,数据的长度起始，要发送给谁DatagramPacket packet = new DatagramPacket(msg.getBytes(), 0, msg.getBytes().length, localhost, port);//3.发送包socket.send(packet);//4.关闭流socket.close();}
}

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