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 java.io.DataInput; 60 import java.io.DataOutput; 61 import java.io.IOException; 62 import java.io.InvalidObjectException; 63 import java.io.ObjectStreamException; 64 import java.io.Serializable; 65 import java.time.DateTimeException; 66 import java.time.LocalDate; 67 import java.time.temporal.Era; 68 import java.util.Arrays; 69 70 import sun.util.calendar.CalendarDate; 71 72 /** 73 * An era in the Japanese Imperial calendar system. 74 * <p> 75 * This class defines the valid eras for the Japanese chronology. 76 * Only Meiji (1868-09-08 - 1912-07-29) and later eras are supported. 77 * Japan introduced the Gregorian calendar since Meiji 6. The dates 78 * between Meiji 1 - 5 are not historically correct. 79 * The older eras are recognized as Seireki (Western calendar) era, 80 * and the year of era of Seireki is proleptic Gregorian year. 81 * (The Julian to Gregorian transition is not supported.) 82 * 83 * <h3>Specification for implementors</h3> 84 * This class is immutable and thread-safe. 85 * 86 * @since 1.8 87 */ 88 final class JapaneseEra 89 implements Era<JapaneseChrono>, Serializable { 90 91 // The offset value to 0-based index from the era value. 92 // i.e., getValue() + ERA_OFFSET == 0-based index; except that -999 is mapped to zero 93 static final int ERA_OFFSET = 2; 94 95 static final sun.util.calendar.Era[] ERA_CONFIG; 96 97 /** 98 * The singleton instance for the before Meiji era ( - 1868-09-07) 99 * which has the value -999. 100 */ 101 public static final JapaneseEra SEIREKI = new JapaneseEra(-999, LocalDate.MIN); 102 /** 103 * The singleton instance for the 'Meiji' era (1868-09-08 - 1912-07-29) 104 * which has the value -1. 105 */ 106 public static final JapaneseEra MEIJI = new JapaneseEra(-1, LocalDate.of(1868, 9, 8)); 107 /** 108 * The singleton instance for the 'Taisho' era (1912-07-30 - 1926-12-24) 109 * which has the value 0. 110 */ 111 public static final JapaneseEra TAISHO = new JapaneseEra(0, LocalDate.of(1912, 7, 30)); 112 /** 113 * The singleton instance for the 'Showa' era (1926-12-25 - 1989-01-07) 114 * which has the value 1. 115 */ 116 public static final JapaneseEra SHOWA = new JapaneseEra(1, LocalDate.of(1926, 12, 25)); 117 /** 118 * The singleton instance for the 'Heisei' era (1989-01-08 - current) 119 * which has the value 2. 120 */ 121 public static final JapaneseEra HEISEI = new JapaneseEra(2, LocalDate.of(1989, 1, 8)); 122 123 // the number of defined JapaneseEra constants. 124 // There could be an extra era defined in its configuration. 125 private static final int N_ERA_CONSTANTS = HEISEI.getValue() + ERA_OFFSET + 1; 126 127 /** 128 * Serialization version. 129 */ 130 private static final long serialVersionUID = 1466499369062886794L; 131 132 // array for the singleton JapaneseEra instances 133 private static final JapaneseEra[] KNOWN_ERAS; 134 135 static { 136 sun.util.calendar.Era[] sunEras = JapaneseChrono.JCAL.getEras(); 137 ERA_CONFIG = new sun.util.calendar.Era[sunEras.length + 1]; 138 for (int i = 1; i < ERA_CONFIG.length; i++) { 139 ERA_CONFIG[i] = sunEras[i - 1]; 140 } 141 KNOWN_ERAS = new JapaneseEra[ERA_CONFIG.length]; 142 KNOWN_ERAS[0] = SEIREKI; 143 KNOWN_ERAS[1] = MEIJI; 144 KNOWN_ERAS[2] = TAISHO; 145 KNOWN_ERAS[3] = SHOWA; 146 KNOWN_ERAS[4] = HEISEI; 147 for (int i = N_ERA_CONSTANTS; i < ERA_CONFIG.length; i++) { 148 CalendarDate date = ERA_CONFIG[i].getSinceDate(); 149 LocalDate isoDate = LocalDate.of(date.getYear(), date.getMonth(), date.getDayOfMonth()); 150 KNOWN_ERAS[i] = new JapaneseEra(i - ERA_OFFSET, isoDate); 151 } 152 }; 153 154 /** 155 * The era value. 156 * @serial 157 */ 158 private final int eraValue; 159 160 // the first day of the era 161 private final transient LocalDate since; 162 163 /** 164 * Creates an instance. 165 * 166 * @param eraValue the era value, validated 167 * @param since the date representing the first date of the era, validated not null 168 */ 169 private JapaneseEra(int eraValue, LocalDate since) { 170 this.eraValue = eraValue; 171 this.since = since; 172 } 173 174 /** 175 * Returns the singleton {@code JapaneseEra} corresponding to this object. 176 * It's possible that this version of {@code JapaneseEra} doesn't support the latest era value. 177 * In that case, this method throws an {@code ObjectStreamException}. 178 * 179 * @return the singleton {@code JapaneseEra} for this object 180 * @throws ObjectStreamException if the deserialized object has any unknown numeric era value. 181 */ 182 private Object readResolve() throws ObjectStreamException { 183 try { 184 return of(eraValue); 185 } catch (DateTimeException e) { 186 InvalidObjectException ex = new InvalidObjectException("Invalid era"); 187 ex.initCause(e); 188 throw ex; 189 } 190 } 191 192 //----------------------------------------------------------------------- 193 /** 194 * Returns the Sun private Era instance corresponding to this {@code JapaneseEra}. 195 * SEIREKI doesn't have its corresponding one. 196 * 197 * @return the Sun private Era instance for this {@code JapaneseEra}, 198 * or null for SEIREKI. 199 */ 200 sun.util.calendar.Era getPrivateEra() { 201 return ERA_CONFIG[ordinal(eraValue)]; 202 } 203 204 //----------------------------------------------------------------------- 205 /** 206 * Obtains an instance of {@code JapaneseEra} from a value. 207 * <p> 208 * The {@link #SHOWA} era that contains 1970-01-01 (ISO calendar system) has the value 1 209 * Later era is numbered 2 ({@link #HEISEI}). Earlier eras are numbered 0 ({@link #TAISHO}), 210 * -1 ({@link #MEIJI}), only Meiji and later eras are supported. The prior to Meiji, 211 * {@link #SEIREKI} is used. 212 * 213 * @param japaneseEra the era to represent 214 * @return the {@code JapaneseEra} singleton, never null 215 * @throws DateTimeException if {@code japaneseEra} is invalid 216 */ 217 public static JapaneseEra of(int japaneseEra) { 218 if (japaneseEra != SEIREKI.eraValue && 219 (japaneseEra < MEIJI.eraValue || japaneseEra > HEISEI.eraValue)) { 220 throw new DateTimeException("japaneseEra is invalid"); 221 } 222 return KNOWN_ERAS[ordinal(japaneseEra)]; 223 } 224 225 /** 226 * Returns an array of JapaneseEras. 227 * @return an array of JapaneseEras 228 */ 229 static JapaneseEra[] values() { 230 return Arrays.copyOf(KNOWN_ERAS, KNOWN_ERAS.length); 231 } 232 233 //----------------------------------------------------------------------- 234 /** 235 * Obtains an instance of {@code JapaneseEra} from a date. 236 * 237 * @param date the date, not null 238 * @return the Era singleton, never null 239 */ 240 static JapaneseEra from(LocalDate date) { 241 for (int i = KNOWN_ERAS.length - 1; i > 0; i--) { 242 JapaneseEra era = KNOWN_ERAS[i]; 243 if (date.compareTo(era.since) >= 0) { 244 return era; 245 } 246 } 247 return SEIREKI; 248 } 249 250 static JapaneseEra toJapaneseEra(sun.util.calendar.Era privateEra) { 251 for (int i = ERA_CONFIG.length - 1; i > 0; i--) { 252 if (ERA_CONFIG[i].equals(privateEra)) { 253 return KNOWN_ERAS[i]; 254 } 255 } 256 return SEIREKI; 257 } 258 259 static sun.util.calendar.Era privateEraFrom(LocalDate isoDate) { 260 for (int i = KNOWN_ERAS.length - 1; i > 0; i--) { 261 JapaneseEra era = KNOWN_ERAS[i]; 262 if (isoDate.compareTo(era.since) >= 0) { 263 return ERA_CONFIG[i]; 264 } 265 } 266 return null; 267 } 268 269 /** 270 * Returns the index into the arrays from the Era value. 271 * the eraValue is a valid Era number, -999, -1..2. 272 * @param eravalue the era value to convert to the index 273 * @return the index of the current Era 274 */ 275 private static int ordinal(int eravalue) { 276 return (eravalue == SEIREKI.eraValue) ? 0 : eravalue + ERA_OFFSET; 277 } 278 279 //----------------------------------------------------------------------- 280 /** 281 * Returns the numeric value of this {@code JapaneseEra}. 282 * <p> 283 * The {@link #SHOWA} era that contains 1970-01-01 (ISO calendar system) has the value 1. 284 * Later eras are numbered from 2 ({@link #HEISEI}). 285 * Earlier eras are numbered 0 ({@link #TAISHO}), -1 ({@link #MEIJI}), and -999 ({@link #SEIREKI}). 286 * 287 * @return the era value 288 */ 289 @Override 290 public int getValue() { 291 return eraValue; 292 } 293 294 @Override 295 public JapaneseChrono getChrono() { 296 return JapaneseChrono.INSTANCE; 297 } 298 299 //----------------------------------------------------------------------- 300 String getAbbreviation() { 301 int index = ordinal(getValue()); 302 if (index == 0) { 303 return ""; 304 } 305 return ERA_CONFIG[index].getAbbreviation(); 306 } 307 308 String getName() { 309 int index = ordinal(getValue()); 310 if (index == 0) { 311 return "Seireki"; 312 } 313 return ERA_CONFIG[index].getName(); 314 } 315 316 @Override 317 public String toString() { 318 return getName(); 319 } 320 321 //----------------------------------------------------------------------- 322 private Object writeReplace() { 323 return new Ser(Ser.JAPANESE_ERA_TYPE, this); 324 } 325 326 void writeExternal(DataOutput out) throws IOException { 327 out.writeByte(this.getValue()); 328 } 329 330 static JapaneseEra readExternal(DataInput in) throws IOException { 331 byte eraValue = in.readByte(); 332 return JapaneseEra.of(eraValue); 333 } 334 335 }