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    1   /*
    2    * Copyright 2001-2005 The Apache Software Foundation
    3    *
    4    * Licensed under the Apache License, Version 2.0 (the "License");
    5    * you may not use this file except in compliance with the License.
    6    * You may obtain a copy of the License at
    7    *
    8    *     http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  package examples;
    17
    18  import java.io.IOException;
    19  import java.net.InetAddress;
    20  import org.apache.commons.net.TimeTCPClient;
    21  import org.apache.commons.net.TimeUDPClient;
    22
    23  /****
    24   * This is an example program demonstrating how to use the TimeTCPClient
    25   * and TimeUDPClient classes.  It's very similar to the simple Unix rdate
    26   * command.  This program connects to the default time service port of a
    27   * specified server, retrieves the time, and prints it to standard output.
    28   * The default is to use the TCP port.  Use the -udp flag to use the UDP
    29   * port.  You can test this program by using the NIST time server at
    30   * 132.163.135.130 (warning: the IP address may change).
    31   * <p>
    32   * Usage: rdate [-udp] <hostname>
    33   * <p>
    34   * <p>
    35   * @author Daniel F. Savarese
    36   ***/
    37  public final class rdate
    38  {
    39
    40      public static final void timeTCP(String host) throws IOException
    41      {
    42          TimeTCPClient client = new TimeTCPClient();
    43
    44          // We want to timeout if a response takes longer than 60 seconds
    45          client.setDefaultTimeout(60000);
    46          client.connect(host);
    47          System.out.println(client.getDate().toString());
    48          client.disconnect();
    49      }
    50
    51      public static final void timeUDP(String host) throws IOException
    52      {
    53          TimeUDPClient client = new TimeUDPClient();
    54
    55          // We want to timeout if a response takes longer than 60 seconds
    56          client.setDefaultTimeout(60000);
    57          client.open();
    58          System.out.println(client.getDate(InetAddress.getByName(host)).toString());
    59          client.close();
    60      }
    61
    62
    63      public static final void main(String[] args)
    64      {
    65
    66          if (args.length == 1)
    67          {
    68              try
    69              {
    70                  timeTCP(args[0]);
    71              }
    72              catch (IOException e)
    73              {
    74                  e.printStackTrace();
    75                  System.exit(1);
    76              }
    77          }
    78          else if (args.length == 2 && args[0].equals("-udp"))
    79          {
    80              try
    81              {
    82                  timeUDP(args[1]);
    83              }
    84              catch (IOException e)
    85              {
    86                  e.printStackTrace();
    87                  System.exit(1);
    88              }
    89          }
    90          else
    91          {
    92              System.err.println("Usage: rdate [-udp] <hostname>");
    93              System.exit(1);
    94          }
    95
    96      }
    97
    98  }
    99