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