001 package examples.ntp; 002 003 /* 004 * Licensed to the Apache Software Foundation (ASF) under one or more 005 * contributor license agreements. See the NOTICE file distributed with 006 * this work for additional information regarding copyright ownership. 007 * The ASF licenses this file to You under the Apache License, Version 2.0 008 * (the "License"); you may not use this file except in compliance with 009 * the License. You may obtain a copy of the License at 010 * 011 * http://www.apache.org/licenses/LICENSE-2.0 012 * 013 * Unless required by applicable law or agreed to in writing, software 014 * distributed under the License is distributed on an "AS IS" BASIS, 015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 016 * See the License for the specific language governing permissions and 017 * limitations under the License. 018 */ 019 020 021 import java.io.IOException; 022 import java.net.InetAddress; 023 024 import org.apache.commons.net.time.TimeTCPClient; 025 import org.apache.commons.net.time.TimeUDPClient; 026 027 /*** 028 * This is an example program demonstrating how to use the TimeTCPClient 029 * and TimeUDPClient classes. 030 * This program connects to the default time service port of a 031 * specified server, retrieves the time, and prints it to standard output. 032 * See <A HREF="ftp://ftp.rfc-editor.org/in-notes/rfc868.txt"> the spec </A> 033 * for details. The default is to use the TCP port. Use the -udp flag to 034 * use the UDP port. 035 * <p> 036 * Usage: TimeClient [-udp] <hostname> 037 * <p> 038 ***/ 039 public final class TimeClient 040 { 041 042 public static final void timeTCP(String host) throws IOException 043 { 044 TimeTCPClient client = new TimeTCPClient(); 045 try { 046 // We want to timeout if a response takes longer than 60 seconds 047 client.setDefaultTimeout(60000); 048 client.connect(host); 049 System.out.println(client.getDate()); 050 } finally { 051 client.disconnect(); 052 } 053 } 054 055 public static final void timeUDP(String host) throws IOException 056 { 057 TimeUDPClient client = new TimeUDPClient(); 058 059 // We want to timeout if a response takes longer than 60 seconds 060 client.setDefaultTimeout(60000); 061 client.open(); 062 System.out.println(client.getDate(InetAddress.getByName(host))); 063 client.close(); 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: TimeClient [-udp] <hostname>"); 096 System.exit(1); 097 } 098 099 } 100 101 } 102