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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package examples.unix;
19  
20  import java.io.IOException;
21  import java.net.InetAddress;
22  
23  import org.apache.commons.net.time.TimeTCPClient;
24  import org.apache.commons.net.time.TimeUDPClient;
25  
26  /***
27   * This is an example program demonstrating how to use the TimeTCPClient
28   * and TimeUDPClient classes.  It's very similar to the simple Unix rdate
29   * command.  This program connects to the default time service port of a
30   * specified server, retrieves the time, and prints it to standard output.
31   * The default is to use the TCP port.  Use the -udp flag to use the UDP
32   * port.  You can test this program by using the NIST time server at
33   * 132.163.135.130 (warning: the IP address may change).
34   * <p>
35   * Usage: rdate [-udp] <hostname>
36   * <p>
37   * <p>
38   ***/
39  public final class rdate
40  {
41  
42      public static final void timeTCP(String host) throws IOException
43      {
44          TimeTCPClient client = new TimeTCPClient();
45  
46          // We want to timeout if a response takes longer than 60 seconds
47          client.setDefaultTimeout(60000);
48          client.connect(host);
49          System.out.println(client.getDate().toString());
50          client.disconnect();
51      }
52  
53      public static final void timeUDP(String host) throws IOException
54      {
55          TimeUDPClient client = new TimeUDPClient();
56  
57          // We want to timeout if a response takes longer than 60 seconds
58          client.setDefaultTimeout(60000);
59          client.open();
60          System.out.println(client.getDate(InetAddress.getByName(host)).toString());
61          client.close();
62      }
63  
64  
65      public static void main(String[] args)
66      {
67  
68          if (args.length == 1)
69          {
70              try
71              {
72                  timeTCP(args[0]);
73              }
74              catch (IOException e)
75              {
76                  e.printStackTrace();
77                  System.exit(1);
78              }
79          }
80          else if (args.length == 2 && args[0].equals("-udp"))
81          {
82              try
83              {
84                  timeUDP(args[1]);
85              }
86              catch (IOException e)
87              {
88                  e.printStackTrace();
89                  System.exit(1);
90              }
91          }
92          else
93          {
94              System.err.println("Usage: rdate [-udp] <hostname>");
95              System.exit(1);
96          }
97  
98      }
99  
100 }
101