Java-网络编程-UDP

1、send方

package cn.bruce.internetkeyboard;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Scanner;

/*
 * 实现UDP协议发送端：
 * 实现封装数据的类：java.net.DatagramPacket 将你的数据包装
 * 实现封装传输的类：java.net.DatagramSocket 将数据包发出去
 * 实现步骤：
 * 1、创建DatagramPacket对象，封装数据，接受的地址和端口
 * 2、创建DatagramSocket，并调用send方法，发送数据报包
 * 3、关闭资源
 */
public class UDPSEND {
    public static void main(String[] args) throws IOException {
        Scanner sc = new Scanner(System.in);
        InetAddress inet = InetAddress.getByName("127.0.0.1");// 封装接收IP
        DatagramSocket DS = new DatagramSocket();
        while (true)
        {
            byte[] data = sc.nextLine().getBytes();// 封装数据
            // 封装数据报包
            DatagramPacket dPacket = new DatagramPacket(data, data.length, inet, 6033);
            // 发送数据
            DS.send(dPacket);
        }
        // 关闭资源
        // DS.close();
    }

}

2、receive方

package cn.bruce.internetkeyboard;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;

public class UDPRECEIVE {
    public static void main(String[] args) throws IOException {
        DatagramSocket datagramSocket = new DatagramSocket(6033);
        byte[] data = new byte[1024];
        
        while (true)
        {
            DatagramPacket dPacket = new DatagramPacket(data, data.length);
            datagramSocket.receive(dPacket);
            System.out.println(new String(data, 0, dPacket.getLength()));
        } // 长度使用方法来获取
        // datagramSocket.close();
    }
}

先运行receive，进行线程等待，再运行send，进行文字输入