UDP

package IntTest;

import org.junit.Test;

import java.io.IOException;
import java.net.*;

public class UDPTest {

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

        String str="12334";
        byte [] by=str.getBytes();
        InetAddress inet=InetAddress.getByName("192.168.1.107");
        //DatagramPacket 对象封装了UDP数据报，在数据报中包含了发送端的IP和端口号, 以及接受端的IP地址和端口号
        DatagramPacket packet=new DatagramPacket(by,0,by.length,inet,9091);
        socket.send(packet);

        socket.close();

    }

    @Test
    public void receiver() throws IOException {

        DatagramSocket socket = new DatagramSocket(9091);

        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();
    }


}