001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.net.examples.ntp;
019
020import java.io.IOException;
021import java.net.InetAddress;
022import java.time.Duration;
023
024import org.apache.commons.net.time.TimeTCPClient;
025import org.apache.commons.net.time.TimeUDPClient;
026
027/**
028 * This is an example program demonstrating how to use the TimeTCPClient and TimeUDPClient classes. This program connects to the default time service port of a
029 * specified server, retrieves the time, and prints it to standard output. See <A HREF="ftp://ftp.rfc-editor.org/in-notes/rfc868.txt"> the spec </A> for
030 * details. The default is to use the TCP port. Use the -udp flag to use the UDP port.
031 * <p>
032 * Usage: TimeClient [-udp] <hostname>
033 * </p>
034 */
035public final class TimeClient {
036
037    public static void main(final String[] args) {
038
039        if (args.length == 1) {
040            try {
041                timeTCP(args[0]);
042            } catch (final IOException e) {
043                e.printStackTrace();
044                System.exit(1);
045            }
046        } else if (args.length == 2 && args[0].equals("-udp")) {
047            try {
048                timeUDP(args[1]);
049            } catch (final IOException e) {
050                e.printStackTrace();
051                System.exit(1);
052            }
053        } else {
054            System.err.println("Usage: TimeClient [-udp] <hostname>");
055            System.exit(1);
056        }
057
058    }
059
060    public static void timeTCP(final String host) throws IOException {
061        final TimeTCPClient client = new TimeTCPClient();
062        try {
063            // We want to timeout if a response takes longer than 60 seconds
064            client.setDefaultTimeout(60000);
065            client.connect(host);
066            System.out.println(client.getDate());
067        } finally {
068            client.disconnect();
069        }
070    }
071
072    public static void timeUDP(final String host) throws IOException {
073        final TimeUDPClient client = new TimeUDPClient();
074
075        // We want to timeout if a response takes longer than 60 seconds
076        client.setDefaultTimeout(Duration.ofSeconds(60));
077        client.open();
078        System.out.println(client.getDate(InetAddress.getByName(host)));
079        client.close();
080    }
081
082}