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.calendar;
58
59 import static java.time.temporal.ChronoField.YEAR;
60
61 import java.io.Serializable;
62 import java.time.DateTimeException;
63 import java.time.LocalDate;
64 import java.time.temporal.Chrono;
65 import java.time.temporal.ChronoField;
66 import java.time.temporal.ChronoLocalDate;
67 import java.time.temporal.Era;
68 import java.time.temporal.ISOChrono;
69 import java.time.temporal.TemporalAccessor;
70 import java.time.temporal.ValueRange;
71 import java.util.Arrays;
72 import java.util.List;
73 import java.util.Locale;
74
75 /**
76 * The Minguo calendar system.
77 * <p>
78 * This chronology defines the rules of the Minguo calendar system.
79 * This calendar system is primarily used in the Republic of China, often known as Taiwan.
80 * Dates are aligned such that {@code 0001-01-01 (Minguo)} is {@code 1911-01-01 (ISO)}.
81 * <p>
82 * The fields are defined as follows:
83 * <p><ul>
84 * <li>era - There are two eras, the current 'Republic' (ERA_ROC) and the previous era (ERA_BEFORE_ROC).
85 * <li>year-of-era - The year-of-era for the current era increases uniformly from the epoch at year one.
86 * For the previous era the year increases from one as time goes backwards.
87 * The value for the current era is equal to the ISO proleptic-year minus 1911.
88 * <li>proleptic-year - The proleptic year is the same as the year-of-era for the
89 * current era. For the previous era, years have zero, then negative values.
90 * The value is equal to the ISO proleptic-year minus 1911.
91 * <li>month-of-year - The Minguo month-of-year exactly matches ISO.
92 * <li>day-of-month - The Minguo day-of-month exactly matches ISO.
93 * <li>day-of-year - The Minguo day-of-year exactly matches ISO.
94 * <li>leap-year - The Minguo leap-year pattern exactly matches ISO, such that the two calendars
95 * are never out of step.
96 * </ul><p>
97 *
98 * <h3>Specification for implementors</h3>
99 * This class is immutable and thread-safe.
100 *
101 * @since 1.8
102 */
103 public final class MinguoChrono extends Chrono<MinguoChrono> implements Serializable {
104
105 /**
106 * Singleton instance for the Minguo chronology.
107 */
108 public static final MinguoChrono INSTANCE = new MinguoChrono();
109
110 /**
111 * The singleton instance for the era ROC.
112 */
113 public static final Era<MinguoChrono> ERA_ROC = MinguoEra.ROC;
114
115 /**
116 * The singleton instance for the era BEFORE_ROC.
117 */
118 public static final Era<MinguoChrono> ERA_BEFORE_ROC = MinguoEra.BEFORE_ROC;
119
120 /**
121 * Serialization version.
122 */
123 private static final long serialVersionUID = 1039765215346859963L;
124 /**
125 * The difference in years between ISO and Minguo.
126 */
127 static final int YEARS_DIFFERENCE = 1911;
128
129 /**
130 * Restricted constructor.
131 */
132 private MinguoChrono() {
133 }
134
135 /**
136 * Resolve singleton.
137 *
138 * @return the singleton instance, not null
139 */
140 private Object readResolve() {
141 return INSTANCE;
142 }
143
144 //-----------------------------------------------------------------------
145 /**
146 * Gets the ID of the chronology - 'Minguo'.
147 * <p>
148 * The ID uniquely identifies the {@code Chrono}.
149 * It can be used to lookup the {@code Chrono} using {@link #of(String)}.
150 *
151 * @return the chronology ID - 'Minguo'
152 * @see #getCalendarType()
153 */
154 @Override
155 public String getId() {
156 return "Minguo";
157 }
158
159 /**
160 * Gets the calendar type of the underlying calendar system - 'roc'.
161 * <p>
162 * The calendar type is an identifier defined by the
163 * <em>Unicode Locale Data Markup Language (LDML)</em> specification.
164 * It can be used to lookup the {@code Chrono} using {@link #of(String)}.
165 * It can also be used as part of a locale, accessible via
166 * {@link Locale#getUnicodeLocaleType(String)} with the key 'ca'.
167 *
168 * @return the calendar system type - 'roc'
169 * @see #getId()
170 */
171 @Override
172 public String getCalendarType() {
173 return "roc";
174 }
175
176 //-----------------------------------------------------------------------
177 @Override
178 public ChronoLocalDate<MinguoChrono> date(int prolepticYear, int month, int dayOfMonth) {
179 return new MinguoDate(LocalDate.of(prolepticYear + YEARS_DIFFERENCE, month, dayOfMonth));
180 }
181
182 @Override
183 public ChronoLocalDate<MinguoChrono> dateYearDay(int prolepticYear, int dayOfYear) {
184 return new MinguoDate(LocalDate.ofYearDay(prolepticYear + YEARS_DIFFERENCE, dayOfYear));
185 }
186
187 @Override
188 public ChronoLocalDate<MinguoChrono> date(TemporalAccessor temporal) {
189 if (temporal instanceof MinguoDate) {
190 return (MinguoDate) temporal;
191 }
192 return new MinguoDate(LocalDate.from(temporal));
193 }
194
195 //-----------------------------------------------------------------------
196 /**
197 * Checks if the specified year is a leap year.
198 * <p>
199 * Minguo leap years occur exactly in line with ISO leap years.
200 * This method does not validate the year passed in, and only has a
201 * well-defined result for years in the supported range.
202 *
203 * @param prolepticYear the proleptic-year to check, not validated for range
204 * @return true if the year is a leap year
205 */
206 @Override
207 public boolean isLeapYear(long prolepticYear) {
208 return ISOChrono.INSTANCE.isLeapYear(prolepticYear + YEARS_DIFFERENCE);
209 }
210
211 @Override
212 public int prolepticYear(Era<MinguoChrono> era, int yearOfEra) {
213 if (era instanceof MinguoEra == false) {
214 throw new DateTimeException("Era must be MinguoEra");
215 }
216 return (era == MinguoEra.ROC ? yearOfEra : 1 - yearOfEra);
217 }
218
219 @Override
220 public Era<MinguoChrono> eraOf(int eraValue) {
221 return MinguoEra.of(eraValue);
222 }
223
224 @Override
225 public List<Era<MinguoChrono>> eras() {
226 return Arrays.<Era<MinguoChrono>>asList(MinguoEra.values());
227 }
228
229 //-----------------------------------------------------------------------
230 @Override
231 public ValueRange range(ChronoField field) {
232 switch (field) {
233 case YEAR_OF_ERA: {
234 ValueRange range = YEAR.range();
235 return ValueRange.of(1, range.getMaximum() - YEARS_DIFFERENCE, -range.getMinimum() + 1 + YEARS_DIFFERENCE);
236 }
237 case YEAR: {
238 ValueRange range = YEAR.range();
239 return ValueRange.of(range.getMinimum() - YEARS_DIFFERENCE, range.getMaximum() - YEARS_DIFFERENCE);
240 }
241 }
242 return field.range();
243 }
244
245 }