1 /*
2  * Copyright (c) 2003, 2019, 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  * <pre>{@code
45  *   Calendar system         Era name         Since (in Gregorian)
46  *   -----------------------------------------------------------------------
47  *   Japanese calendar       Meiji            1868-01-01T00:00:00 local time
48  *                           Taisho           1912-07-30T00:00:00 local time
49  *                           Showa            1926-12-25T00:00:00 local time
50  *                           Heisei           1989-01-08T00:00:00 local time
51  *                           Reiwa            2019-05-01T00:00:00 local time
52  *   -----------------------------------------------------------------------
53  * }</pre>
54  *
55  * @author Masayoshi Okutsu
56  * @since 1.5
57  */
58 
59 public final class Era {
60     private final String name;
61     private final String abbr;
62     private final long since;
63     private final CalendarDate sinceDate;
64     private final boolean localTime;
65 
66     /**
67      * Constructs an <code>Era</code> instance.
68      *
69      * @param name the era name (e.g., "BeforeCommonEra" for the Julian calendar system)
70      * @param abbr the abbreviation of the era name (e.g., "B.C.E." for "BeforeCommonEra")
71      * @param since the time (millisecond offset from January 1, 1970
72      * (Gregorian) UTC or local time) when the era starts, inclusive.
73      * @param localTime <code>true</code> if <code>since</code>
74      * specifies a local time; <code>false</code> if
75      * <code>since</code> specifies UTC
76      */
Era(String name, String abbr, long since, boolean localTime)77     public Era(String name, String abbr, long since, boolean localTime) {
78         this.name = name;
79         this.abbr = abbr;
80         this.since = since;
81         this.localTime = localTime;
82         Gregorian gcal = CalendarSystem.getGregorianCalendar();
83         BaseCalendar.Date d = (BaseCalendar.Date) gcal.newCalendarDate(null);
84         gcal.getCalendarDate(since, d);
85         sinceDate = new ImmutableGregorianDate(d);
86     }
87 
getName()88     public String getName() {
89         return name;
90     }
91 
getDisplayName(Locale locale)92     public String getDisplayName(Locale locale) {
93         return name;
94     }
95 
getAbbreviation()96     public String getAbbreviation() {
97         return abbr;
98     }
99 
getDiaplayAbbreviation(Locale locale)100     public String getDiaplayAbbreviation(Locale locale) {
101         return abbr;
102     }
103 
getSince(TimeZone zone)104     public long getSince(TimeZone zone) {
105         if (zone == null || !localTime) {
106             return since;
107         }
108         int offset = zone.getOffset(since);
109         return since - offset;
110     }
111 
getSinceDate()112     public CalendarDate getSinceDate() {
113         return sinceDate;
114     }
115 
isLocalTime()116     public boolean isLocalTime() {
117         return localTime;
118     }
119 
equals(Object o)120     public boolean equals(Object o) {
121         if (!(o instanceof Era)) {
122             return false;
123         }
124         Era that = (Era) o;
125         return name.equals(that.name)
126             && abbr.equals(that.abbr)
127             && since == that.since
128             && localTime == that.localTime;
129     }
130 
131     private int hash = 0;
132 
hashCode()133     public int hashCode() {
134         if (hash == 0) {
135             hash = name.hashCode() ^ abbr.hashCode() ^ (int)since ^ (int)(since >> 32)
136                 ^ (localTime ? 1 : 0);
137         }
138         return hash;
139     }
140 
toString()141     public String toString() {
142         StringBuilder sb = new StringBuilder();
143         sb.append('[');
144         sb.append(getName()).append(" (");
145         sb.append(getAbbreviation()).append(')');
146         sb.append(" since ").append(getSinceDate());
147         if (localTime) {
148             sb.setLength(sb.length() - 1); // remove 'Z'
149             sb.append(" local time");
150         }
151         sb.append(']');
152         return sb.toString();
153     }
154 }
155