基础网络编程

先定义udp接收方

package internet;

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 {
        //创建接收对象 端口号
        DatagramSocket ds =new DatagramSocket(12345);
        while(true){
            //创建数据包 用了接收数据
            byte[]bys=new byte[1024];
            DatagramPacket dp=new DatagramPacket(bys,bys.length);
        //调用DatagrampaSocket对象方法接收数据
            ds.receive(dp);
            //解析数据，并打印
            System.out.println("数据是："+new String(dp.getData(),0,dp.getLength()));

        }
    }
} 
发送方：

package internet;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.nio.charset.StandardCharsets;


public class UdpSend {
    public static void main(String[] args) throws IOException {
        //创建发送端的Socke对象
        DatagramSocket ds=new DatagramSocket();
        //键盘录入封装
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        String line;
        while( (line=br.readLine())!=null){
            if ("886".equals(line)){
                break;
            }
            //创建数据打包
            byte[]bys=line.getBytes();
            DatagramPacket dp=new DatagramPacket(bys,bys.length, InetAddress.getByName("172.20.37.152"),12345);
       ds.send(dp);
        }
       ds.close();
    }
}