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 */ 017 018 package examples; 019 020 import java.io.IOException; 021 import java.net.InetAddress; 022 023 import org.apache.commons.net.time.TimeTCPClient; 024 import org.apache.commons.net.time.TimeUDPClient; 025 026 /*** 027 * This is an example program demonstrating how to use the TimeTCPClient 028 * and TimeUDPClient classes. It's very similar to the simple Unix rdate 029 * command. This program connects to the default time service port of a 030 * specified server, retrieves the time, and prints it to standard output. 031 * The default is to use the TCP port. Use the -udp flag to use the UDP 032 * port. You can test this program by using the NIST time server at 033 * 132.163.135.130 (warning: the IP address may change). 034 * <p> 035 * Usage: rdate [-udp] <hostname> 036 * <p> 037 * <p> 038 * @author Daniel F. Savarese 039 ***/ 040 public final class rdate 041 { 042 043 public static final void timeTCP(String host) throws IOException 044 { 045 TimeTCPClient client = new TimeTCPClient(); 046 047 // We want to timeout if a response takes longer than 60 seconds 048 client.setDefaultTimeout(60000); 049 client.connect(host); 050 System.out.println(client.getDate().toString()); 051 client.disconnect(); 052 } 053 054 public static final void timeUDP(String host) throws IOException 055 { 056 TimeUDPClient client = new TimeUDPClient(); 057 058 // We want to timeout if a response takes longer than 60 seconds 059 client.setDefaultTimeout(60000); 060 client.open(); 061 System.out.println(client.getDate(InetAddress.getByName(host)).toString()); 062 client.close(); 063 } 064 065 066 public static final void main(String[] args) 067 { 068 069 if (args.length == 1) 070 { 071 try 072 { 073 timeTCP(args[0]); 074 } 075 catch (IOException e) 076 { 077 e.printStackTrace(); 078 System.exit(1); 079 } 080 } 081 else if (args.length == 2 && args[0].equals("-udp")) 082 { 083 try 084 { 085 timeUDP(args[1]); 086 } 087 catch (IOException e) 088 { 089 e.printStackTrace(); 090 System.exit(1); 091 } 092 } 093 else 094 { 095 System.err.println("Usage: rdate [-udp] <hostname>"); 096 System.exit(1); 097 } 098 099 } 100 101 } 102