1：客户端程序
package com.pb.udp;import java.io.IOException;import java.net.DatagramPacket;import java.net.InetAddress;import java.net.UnknownHostException;import java.net.DatagramSocket;/** * 使用Sender类来代表客户端程序，， * @author ccna_zhang * */public class Sender {public static void main(String[] args) {String msg = "Hello, World";byte[] buf = msg.getBytes();try {InetAddress address = InetAddress.getByName("192.168.1.80"); //服务器地址int port = 8080; //服务器的端口号//创建发送方的数据报信息DatagramPacket dataGramPacket = new DatagramPacket(buf, buf.length, address, port);DatagramSocket socket = new DatagramSocket(); //创建套接字socket.send(dataGramPacket); //通过套接字发送数据//接收服务器反馈数据byte[] backbuf = new byte[1024];DatagramPacket backPacket = new DatagramPacket(backbuf, backbuf.length);socket.receive(backPacket); //接收返回数据String backMsg = new String(backbuf, 0, backPacket.getLength());System.out.println("服务器返回的数据为:" + backMsg);socket.close();} catch (UnknownHostException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}}
2：服务器端程序
package com.pb.udp;import java.io.IOException;import java.net.DatagramPacket;import java.net.DatagramSocket;import java.net.InetAddress;import java.net.SocketAddress;import java.net.UnknownHostException;/** * 服务器端程序 * @author ccna_zhang * */public class Receiver {public static void main(String[] args) {try {InetAddress address = InetAddress.getLocalHost();int port = 8080;//创建DatagramSocket对象DatagramSocket socket = new DatagramSocket(port, address);byte[] buf = new byte[1024]; //定义byte数组DatagramPacket packet = new DatagramPacket(buf, buf.length); //创建DatagramPacket对象socket.receive(packet); //通过套接字接收数据String getMsg = new String(buf, 0, packet.getLength());System.out.println("客户端发送的数据为：" + getMsg);//从服务器返回给客户端数据InetAddress clientAddress = packet.getAddress(); //获得客户端的IP地址int clientPort = packet.getPort(); //获得客户端的端口号SocketAddress sendAddress = packet.getSocketAddress();String feedback = "Received";byte[] backbuf = feedback.getBytes();DatagramPacket sendPacket = new DatagramPacket(backbuf, backbuf.length, sendAddress); //封装返回给客户端的数据socket.send(sendPacket); //通过套接字反馈服务器数据socket.close(); //关闭套接字} catch (UnknownHostException e) {e.printStackTrace();} catch(IOException e) {e.printStackTrace();}}}
3：程序运行结果
服务器端：
客户端发送的数据为：Hello, World
客户端：
服务器返回的数据为:Received
如果可以，我真想和你一直旅行。或许是某个未开发的荒凉小岛，
