1 /*
   2  * Copyright (c) 2003, 2005, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.util.calendar;
  27 
  28 import java.util.Locale;
  29 import java.util.TimeZone;
  30 
  31 /**
  32  * The class <code>Era</code> represents a calendar era that defines a
  33  * period of time in which the same year numbering is used. For
  34  * example, Gregorian year 2004 is <I>Heisei</I> 16 in the Japanese
  35  * calendar system. An era starts at any point of time (Gregorian) that is
  36  * represented by <code>CalendarDate</code>.
  37  *
  38  * <p><code>Era</code>s that are applicable to a particular calendar
  39  * system can be obtained by calling {@link CalendarSystem#getEras}
  40  * one of which can be used to specify a date in
  41  * <code>CalendarDate</code>.
  42  *
  43  * <p>The following era names are defined in this release.
  44  * <!-- TODO: use HTML table -->
  45  * <pre><tt>
  46  *   Calendar system         Era name         Since (in Gregorian)
  47  *   -----------------------------------------------------------------------
  48  *   Japanese calendar       Meiji            1868-01-01 midnight local time
  49  *                           Taisho           1912-07-30 midnight local time
  50  *                           Showa            1926-12-26 midnight local time
  51  *                           Heisei           1989-01-08 midnight local time
  52  *   Julian calendar         BeforeCommonEra  -292275055-05-16T16:47:04.192Z
  53  *                           CommonEra        0000-12-30 midnight local time
  54  *   Taiwanese calendar      MinGuo           1911-01-01 midnight local time
  55  *   Thai Buddhist calendar  BuddhistEra      -543-01-01 midnight local time
  56  *   -----------------------------------------------------------------------
  57  * </tt></pre>
  58  *
  59  * @author Masayoshi Okutsu
  60  * @since 1.5
  61  */
  62 
  63 public final class Era {
  64     private final String name;
  65     private final String abbr;
  66     private final long since;
  67     private final CalendarDate sinceDate;
  68     private final boolean localTime;
  69 
  70     /**
  71      * Constructs an <code>Era</code> instance.
  72      *
  73      * @param name the era name (e.g., "BeforeCommonEra" for the Julian calendar system)
  74      * @param abbr the abbreviation of the era name (e.g., "B.C.E." for "BeforeCommonEra")
  75      * @param since the time (millisecond offset from January 1, 1970
  76      * (Gregorian) UTC or local time) when the era starts, inclusive.
  77      * @param localTime <code>true</code> if <code>since</code>
  78      * specifies a local time; <code>false</code> if
  79      * <code>since</code> specifies UTC
  80      */
  81     public Era(String name, String abbr, long since, boolean localTime) {
  82         this.name = name;
  83         this.abbr = abbr;
  84         this.since = since;
  85         this.localTime = localTime;
  86         Gregorian gcal = CalendarSystem.getGregorianCalendar();
  87         BaseCalendar.Date d = (BaseCalendar.Date) gcal.newCalendarDate(null);
  88         gcal.getCalendarDate(since, d);
  89         sinceDate = new ImmutableGregorianDate(d);
  90     }
  91 
  92     public String getName() {
  93         return name;
  94     }
  95 
  96     public String getDisplayName(Locale locale) {
  97         return name;
  98     }
  99 
 100     public String getAbbreviation() {
 101         return abbr;
 102     }
 103 
 104     public String getDiaplayAbbreviation(Locale locale) {
 105         return abbr;
 106     }
 107 
 108     public long getSince(TimeZone zone) {
 109         if (zone == null || !localTime) {
 110             return since;
 111         }
 112         int offset = zone.getOffset(since);
 113         return since - offset;
 114     }
 115 
 116     public CalendarDate getSinceDate() {
 117         return sinceDate;
 118     }
 119 
 120     public boolean isLocalTime() {
 121         return localTime;
 122     }
 123 
 124     public boolean equals(Object o) {
 125         if (!(o instanceof Era)) {
 126             return false;
 127         }
 128         Era that = (Era) o;
 129         return name.equals(that.name)
 130             && abbr.equals(that.abbr)
 131             && since == that.since
 132             && localTime == that.localTime;
 133     }
 134 
 135     private int hash = 0;
 136 
 137     public int hashCode() {
 138         if (hash == 0) {
 139             hash = name.hashCode() ^ abbr.hashCode() ^ (int)since ^ (int)(since >> 32)
 140                 ^ (localTime ? 1 : 0);
 141         }
 142         return hash;
 143     }
 144 
 145     public String toString() {
 146         StringBuilder sb = new StringBuilder();
 147         sb.append('[');
 148         sb.append(getName()).append(" (");
 149         sb.append(getAbbreviation()).append(')');
 150         sb.append(" since ").append(getSinceDate());
 151         if (localTime) {
 152             sb.setLength(sb.length() - 1); // remove 'Z'
 153             sb.append(" local time");
 154         }
 155         sb.append(']');
 156         return sb.toString();
 157     }
 158 }