代码如下:

package UdpPracticePack;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.net.SocketException;public class SendDemo {public static void main(String[] args) throws IOException {DatagramSocket ds = new DatagramSocket();BufferedReader br = new BufferedReader(new InputStreamReader(System.in));String line;while((line = br.readLine())!=null){if ("886".equals(line)){break;}byte[] bys = line.getBytes();DatagramPacket dp = new DatagramPacket(bys,bys.length, InetAddress.getByName("192.168.1.123"),12345);ds.send(dp);}ds.close();}}

package UdpPracticePack;import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;public class ReceiveDemo {public static void main(String[] args) throws IOException {DatagramSocket ds = new DatagramSocket(12345);while(true) {byte[] bys = new byte[1024];DatagramPacket dp = new DatagramPacket(bys, bys.length);ds.receive(dp);System.out.println("数据是 " + new String(dp.getData(), 0, dp.getLength()));}//        ds.close();}
}