1 /*
2 * Copyright (c) 2012, 2013, 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 /*
27 * Copyright (c) 2012, Stephen Colebourne & Michael Nascimento Santos
28 *
29 * All rights reserved.
30 *
31 * Redistribution and use in source and binary forms, with or without
32 * modification, are permitted provided that the following conditions are met:
33 *
34 * * Redistributions of source code must retain the above copyright notice,
35 * this list of conditions and the following disclaimer.
36 *
37 * * Redistributions in binary form must reproduce the above copyright notice,
38 * this list of conditions and the following disclaimer in the documentation
39 * and/or other materials provided with the distribution.
40 *
41 * * Neither the name of JSR-310 nor the names of its contributors
42 * may be used to endorse or promote products derived from this software
43 * without specific prior written permission.
44 *
45 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
46 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
47 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
48 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
49 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
50 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
51 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
52 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
53 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
54 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
55 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56 */
57 package java.time.chrono;
58
59 import java.io.DataInput;
60 import java.io.DataOutput;
61 import java.io.IOException;
62 import java.time.DateTimeException;
63
64 /**
65 * An era in the Hijrah calendar system.
66 * <p>
67 * The Hijrah calendar system has two eras.
68 * The date {@code 0001-01-01 (Hijrah)} is {@code 622-06-19 (ISO)}.
69 * <p>
70 * <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code HijrahEra}.
71 * Use {@code getValue()} instead.</b>
72 *
73 * <h3>Specification for implementors</h3>
74 * This is an immutable and thread-safe enum.
75 *
76 * @since 1.8
77 */
78 enum HijrahEra implements Era {
79
80 /**
81 * The singleton instance for the era before the current one, 'Before Anno Hegirae',
82 * which has the value 0.
83 */
84 BEFORE_AH,
85 /**
86 * The singleton instance for the current era, 'Anno Hegirae', which has the value 1.
87 */
88 AH;
89
90 //-----------------------------------------------------------------------
91 /**
92 * Obtains an instance of {@code HijrahEra} from a value.
93 * <p>
94 * The current era (from ISO date 622-06-19 onwards) has the value 1
95 * The previous era has the value 0.
96 *
97 * @param hijrahEra the era to represent, from 0 to 1
98 * @return the HijrahEra singleton, never null
99 * @throws DateTimeException if the era is invalid
100 */
101 public static HijrahEra of(int hijrahEra) {
102 switch (hijrahEra) {
103 case 0:
104 return BEFORE_AH;
105 case 1:
106 return AH;
107 default:
108 throw new DateTimeException("HijrahEra not valid");
109 }
110 }
111
112 //-----------------------------------------------------------------------
113 /**
114 * Gets the era numeric value.
115 * <p>
116 * The current era (from ISO date 622-06-19 onwards) has the value 1.
117 * The previous era has the value 0.
118 *
119 * @return the era value, from 0 (BEFORE_AH) to 1 (AH)
120 */
121 @Override
122 public int getValue() {
123 return ordinal();
124 }
125
126 @Override
127 public HijrahChronology getChronology() {
128 return HijrahChronology.INSTANCE;
129 }
130
131 // JDK8 default methods:
132 //-----------------------------------------------------------------------
133 @Override
134 public HijrahDate date(int year, int month, int day) {
135 return (HijrahDate)(getChronology().date(this, year, month, day));
136 }
137
138 @Override
139 public HijrahDate dateYearDay(int year, int dayOfYear) {
140 return (HijrahDate)(getChronology().dateYearDay(this, year, dayOfYear));
141 }
142
143 //-------------------------------------------------------------------------
144 /**
145 * Returns the proleptic year from this era and year of era.
146 *
147 * @param yearOfEra the year of Era
148 * @return the computed prolepticYear
149 */
150 int prolepticYear(int yearOfEra) {
151 return (this == HijrahEra.AH ? yearOfEra : 1 - yearOfEra);
152 }
153
154 //-----------------------------------------------------------------------
155 private Object writeReplace() {
156 return new Ser(Ser.HIJRAH_ERA_TYPE, this);
157 }
158
159 void writeExternal(DataOutput out) throws IOException {
160 out.writeByte(this.getValue());
161 }
162
163 static HijrahEra readExternal(DataInput in) throws IOException {
164 byte eraValue = in.readByte();
165 return HijrahEra.of(eraValue);
166 }
167
168 }