View Javadoc
1 package org.apache.commons.net; 2 3 /* ==================================================================== 4 * The Apache Software License, Version 1.1 5 * 6 * Copyright (c) 2001 The Apache Software Foundation. All rights 7 * reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * 21 * 3. The end-user documentation included with the redistribution, 22 * if any, must include the following acknowledgment: 23 * "This product includes software developed by the 24 * Apache Software Foundation (http://www.apache.org/)." 25 * Alternately, this acknowledgment may appear in the software itself, 26 * if and wherever such third-party acknowledgments normally appear. 27 * 28 * 4. The names "Apache" and "Apache Software Foundation" and 29 * "Apache Commons" must not be used to endorse or promote products 30 * derived from this software without prior written permission. For 31 * written permission, please contact apache@apache.org. 32 * 33 * 5. Products derived from this software may not be called "Apache", 34 * nor may "Apache" appear in their name, without 35 * prior written permission of the Apache Software Foundation. 36 * 37 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED 38 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 39 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 40 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR 41 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 42 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 43 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 44 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 45 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 46 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 47 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 48 * SUCH DAMAGE. 49 * ==================================================================== 50 * 51 * This software consists of voluntary contributions made by many 52 * individuals on behalf of the Apache Software Foundation. For more 53 * information on the Apache Software Foundation, please see 54 * <http://www.apache.org/>;. 55 */ 56 57 import java.io.IOException; 58 import java.util.Date; 59 import java.io.DataInputStream; 60 61 /**** 62 * The TimeTCPClient class is a TCP implementation of a client for the 63 * Time protocol described in RFC 868. To use the class, merely 64 * establish a connection with 65 * <a href="org.apache.commons.net.SocketClient.html#connect"> connect </a> 66 * and call either <a href="#getTime"> getTime() </a> or 67 * <a href="#getDate"> getDate() </a> to retrieve the time, then 68 * call <a href="org.apache.commons.net.SocketClient.html#disconnect"> disconnect </a> 69 * to close the connection properly. 70 * <p> 71 * <p> 72 * @author Daniel F. Savarese 73 * @see TimeUDPClient 74 ***/ 75 76 public final class TimeTCPClient extends SocketClient 77 { 78 /**** The default time port. It is set to 37 according to RFC 868. ***/ 79 public static final int DEFAULT_PORT = 37; 80 81 /**** 82 * The number of seconds between 00:00 1 January 1900 and 83 * 00:00 1 January 1970. This value can be useful for converting 84 * time values to other formats. 85 ***/ 86 public static final long SECONDS_1900_TO_1970 = 2208988800L; 87 88 /**** 89 * The default TimeTCPClient constructor. It merely sets the default 90 * port to <code> DEFAULT_PORT </code>. 91 ***/ 92 public TimeTCPClient () 93 { 94 setDefaultPort(DEFAULT_PORT); 95 } 96 97 /**** 98 * Retrieves the time from the server and returns it. The time 99 * is the number of seconds since 00:00 (midnight) 1 January 1900 GMT, 100 * as specified by RFC 868. This method reads the raw 32-bit big-endian 101 * unsigned integer from the server, converts it to a Java long, and 102 * returns the value. 103 * <p> 104 * The server will have closed the connection at this point, so you should 105 * call 106 * <a href="org.apache.commons.net.SocketClient.html#disconnect"> disconnect </a> 107 * after calling this method. To retrieve another time, you must 108 * initiate another connection with 109 * <a href="org.apache.commons.net.SocketClient.html#connect"> connect </a> 110 * before calling <code> getTime() </code> again. 111 * <p> 112 * @return The time value retrieved from the server. 113 * @exception IOException If an error occurs while fetching the time. 114 ***/ 115 public long getTime() throws IOException 116 { 117 DataInputStream input; 118 input = new DataInputStream(_input_); 119 return (long)(input.readInt() & 0xffffffffL); 120 } 121 122 /**** 123 * Retrieves the time from the server and returns a Java Date 124 * containing the time converted to the local timezone. 125 * <p> 126 * The server will have closed the connection at this point, so you should 127 * call 128 * <a href="org.apache.commons.net.SocketClient.html#disconnect"> disconnect </a> 129 * after calling this method. To retrieve another time, you must 130 * initiate another connection with 131 * <a href="org.apache.commons.net.SocketClient.html#connect"> connect </a> 132 * before calling <code> getDate() </code> again. 133 * <p> 134 * @return A Date value containing the time retrieved from the server 135 * converted to the local timezone. 136 * @exception IOException If an error occurs while fetching the time. 137 ***/ 138 public Date getDate() throws IOException 139 { 140 return new Date((getTime() - SECONDS_1900_TO_1970)*1000L); 141 } 142 143 } 144

This page was automatically generated by Maven