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; 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 * @author Daniel F. Savarese 39 ***/ 40 public final class rdate 41 { 42 43 public static final void timeTCP(String host) throws IOException 44 { 45 TimeTCPClient client = new TimeTCPClient(); 46 47 // We want to timeout if a response takes longer than 60 seconds 48 client.setDefaultTimeout(60000); 49 client.connect(host); 50 System.out.println(client.getDate().toString()); 51 client.disconnect(); 52 } 53 54 public static final void timeUDP(String host) throws IOException 55 { 56 TimeUDPClient client = new TimeUDPClient(); 57 58 // We want to timeout if a response takes longer than 60 seconds 59 client.setDefaultTimeout(60000); 60 client.open(); 61 System.out.println(client.getDate(InetAddress.getByName(host)).toString()); 62 client.close(); 63 } 64 65 66 public static final void main(String[] args) 67 { 68 69 if (args.length == 1) 70 { 71 try 72 { 73 timeTCP(args[0]); 74 } 75 catch (IOException e) 76 { 77 e.printStackTrace(); 78 System.exit(1); 79 } 80 } 81 else if (args.length == 2 && args[0].equals("-udp")) 82 { 83 try 84 { 85 timeUDP(args[1]); 86 } 87 catch (IOException e) 88 { 89 e.printStackTrace(); 90 System.exit(1); 91 } 92 } 93 else 94 { 95 System.err.println("Usage: rdate [-udp] <hostname>"); 96 System.exit(1); 97 } 98 99 } 100 101 } 102