ntp时间同步端口_网络客户端协议没有了

import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import org.apache.commons.net.ntp.NTPUDPClient;
import org.apache.commons.net.ntp.TimeInfo;
import org.apache.commons.net.ntp.TimeStamp;
public class NTPClient { 

public static void main(String[] args) { 

try { 

NTPUDPClient timeClient = new NTPUDPClient();
String timeServerUrl = "130.149.17.21";
InetAddress timeServerAddress = InetAddress.getByName(timeServerUrl);
TimeInfo timeInfo = timeClient.getTime(timeServerAddress);
TimeStamp timeStamp = timeInfo.getMessage().getTransmitTimeStamp();
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
System.out.println("时间：" + dateFormat.format(timeStamp.getDate()));
} catch (UnknownHostException e) { 

e.printStackTrace();
} catch (IOException e) { 

e.printStackTrace();
}
}
}