Java UDP通信示例

Server端

1. 初始化DatagramSocket:port和ip
2. 用buffer初始化DatagramPacket
3. 接收DatagramPacket
4. 关闭socket

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;public class UDPServer {public static void main(String[] args) {DatagramSocket socket = null;try {try {socket = new DatagramSocket(8080, InetAddress.getByName("127.0.0.1"));} catch (UnknownHostException e) {e.printStackTrace();}} catch (SocketException e) {e.printStackTrace();}// 创建接收缓冲区byte[] buffer = new byte[1024];// 创建接收数据包DatagramPacket receivePacket = new DatagramPacket(buffer, buffer.length);// 接收数据try {socket.receive(receivePacket);} catch (IOException e) {e.printStackTrace();} finally {if (socket != null) {socket.close();}}// 解析消息并打印数据String string = new String(receivePacket.getData(), 0, receivePacket.getLength());System.out.println(string);}
}

Client

1. 初始化DatagramSocket:port和ip
2. 用buffer初始化DatagramPacket
3. 发送DatagramPacket
4. 关闭socket

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;public class UDPClient {public static void main(String[] args) {DatagramSocket socket = null;try {socket = new DatagramSocket();} catch (SocketException e) {e.printStackTrace();}try {InetAddress ip = InetAddress.getByName("127.0.0.1");int port = 8080;byte[] buffer = "Hello world".getBytes();// 创建发送类型的数据包，这个数据包包含了要发往的ip地址和端口DatagramPacket packet = new DatagramPacket(buffer, buffer.length, ip, port);try {socket.send(packet);} catch (IOException e) {e.printStackTrace();} finally {if (socket != null) {socket.close();}}} catch (UnknownHostException e) {e.printStackTrace();}}
}