Server.java

package com.zby;import java.net.DatagramPacket;import java.net.DatagramSocket;public class Server {    private static boolean running = true;    public static void main(String[] args) throws Exception {        DatagramSocket server = new DatagramSocket(8888);        byte[] buffer = new byte[1024];        DatagramPacket requestPacket = new DatagramPacket(buffer, buffer.length);        while (running) {            server.receive(requestPacket);            String request = new String(requestPacket.getData(), 0, requestPacket.getLength());            System.out.println("request:" + request);            System.out.println("InetAddress:" + requestPacket.getAddress());            System.out.println("port:" + requestPacket.getPort());            System.out.println();            String response = "Hello,Client!";            DatagramPacket responsePacket = new DatagramPacket(response.getBytes(), response.getBytes().length,                    requestPacket.getAddress(), requestPacket.getPort());            server.send(responsePacket);        }        server.close();    }}

Client.java

package com.zby;import java.net.DatagramPacket;import java.net.DatagramSocket;import java.net.InetAddress;public class Client {    public static void main(String[] args) throws Exception {        DatagramSocket client = new DatagramSocket(7777);        String request = "Hello,Server!";        DatagramPacket datagramPacket = new DatagramPacket(request.getBytes(), request.getBytes().length,                InetAddress.getLocalHost(), 8888);        client.send(datagramPacket);        byte[] buffer = new byte[1024];        DatagramPacket responsePacket = new DatagramPacket(buffer, buffer.length);        client.receive(responsePacket);        String response = new String(responsePacket.getData(), 0, responsePacket.getLength());        System.out.println("response:" + response);        System.out.println("InetAddress:" + responsePacket.getAddress());        System.out.println("port:" + responsePacket.getPort());        System.out.println();        client.close();    }}