UDPdemo1

package day2;

import org.junit.Test;
import java.io.IOException;
import java.net.*;
import java.nio.charset.StandardCharsets;

public class UDPdemo1 {
    @Test
    public void sender() throws IOException {
        DatagramSocket socket=new DatagramSocket();

        String str="UDP方式发送的消息";
        byte[] data=str.getBytes();
        InetAddress inet=InetAddress.getLocalHost();
        DatagramPacket packet=new DatagramPacket(data,0,data.length,inet,9090);

        socket.send(packet);
        socket.close();
    }

    @Test
    public void receiver() throws IOException {
        DatagramSocket socket=new DatagramSocket(9090);
        byte[] buffer=new byte[100];
        DatagramPacket packet=new DatagramPacket(buffer,0,buffer.length);
        socket.receive(packet);

        System.out.println(new String(packet.getData(),0,packet.getLength()) );
        socket.close();
    }
}