1 /* 2 * Copyright (c) 2012, 2017, 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 * This file is available under and governed by the GNU General Public 28 * License version 2 only, as published by the Free Software Foundation. 29 * However, the following notice accompanied the original version of this 30 * file: 31 * 32 * Copyright (c) 2012, Stephen Colebourne & Michael Nascimento Santos 33 * 34 * All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions are met: 38 * 39 * * Redistributions of source code must retain the above copyright notice, 40 * this list of conditions and the following disclaimer. 41 * 42 * * Redistributions in binary form must reproduce the above copyright notice, 43 * this list of conditions and the following disclaimer in the documentation 44 * and/or other materials provided with the distribution. 45 * 46 * * Neither the name of JSR-310 nor the names of its contributors 47 * may be used to endorse or promote products derived from this software 48 * without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 51 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 52 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 53 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 54 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 55 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 56 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 57 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 58 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 59 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 60 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 61 */ 62 package java.time.chrono; 63 64 import static java.time.chrono.JapaneseDate.MEIJI_6_ISODATE; 65 import static java.time.temporal.ChronoField.ERA; 66 67 import java.io.DataInput; 68 import java.io.DataOutput; 69 import java.io.IOException; 70 import java.io.InvalidObjectException; 71 import java.io.ObjectInputStream; 72 import java.io.ObjectStreamException; 73 import java.io.Serializable; 74 import java.time.DateTimeException; 75 import java.time.LocalDate; 76 import java.time.format.TextStyle; 77 import java.time.temporal.ChronoField; 78 import java.time.temporal.TemporalField; 79 import java.time.temporal.UnsupportedTemporalTypeException; 80 import java.time.temporal.ValueRange; 81 import java.util.Arrays; 82 import java.util.Locale; 83 import java.util.Objects; 84 85 import sun.util.calendar.CalendarDate; 86 87 /** 88 * An era in the Japanese Imperial calendar system. 89 * <p> 90 * This class defines the valid eras for the Japanese chronology. 91 * Japan introduced the Gregorian calendar starting with Meiji 6. 92 * Only Meiji and later eras are supported; 93 * dates before Meiji 6, January 1 are not supported. 94 * 95 * @implSpec 96 * This class is immutable and thread-safe. 97 * 98 * @since 1.8 99 */ 100 public final class JapaneseEra 101 implements Era, Serializable { 102 103 // The offset value to 0-based index from the era value. 104 // i.e., getValue() + ERA_OFFSET == 0-based index 105 static final int ERA_OFFSET = 2; 106 107 static final sun.util.calendar.Era[] ERA_CONFIG; 108 109 /** 110 * The singleton instance for the 'Meiji' era (1868-01-01 - 1912-07-29) 111 * which has the value -1. 112 */ 113 public static final JapaneseEra MEIJI = new JapaneseEra(-1, LocalDate.of(1868, 1, 1)); 114 /** 115 * The singleton instance for the 'Taisho' era (1912-07-30 - 1926-12-24) 116 * which has the value 0. 117 */ 118 public static final JapaneseEra TAISHO = new JapaneseEra(0, LocalDate.of(1912, 7, 30)); 119 /** 120 * The singleton instance for the 'Showa' era (1926-12-25 - 1989-01-07) 121 * which has the value 1. 122 */ 123 public static final JapaneseEra SHOWA = new JapaneseEra(1, LocalDate.of(1926, 12, 25)); 124 /** 125 * The singleton instance for the 'Heisei' era (1989-01-08 - current) 126 * which has the value 2. 127 */ 128 public static final JapaneseEra HEISEI = new JapaneseEra(2, LocalDate.of(1989, 1, 8)); 129 130 // The number of predefined JapaneseEra constants. 131 // There may be a supplemental era defined by the property. 132 private static final int N_ERA_CONSTANTS = HEISEI.getValue() + ERA_OFFSET; 133 134 /** 135 * Serialization version. 136 */ 137 private static final long serialVersionUID = 1466499369062886794L; 138 139 // array for the singleton JapaneseEra instances 140 private static final JapaneseEra[] KNOWN_ERAS; 141 142 static { 143 ERA_CONFIG = JapaneseChronology.JCAL.getEras(); 144 145 KNOWN_ERAS = new JapaneseEra[ERA_CONFIG.length]; 146 KNOWN_ERAS[0] = MEIJI; 147 KNOWN_ERAS[1] = TAISHO; 148 KNOWN_ERAS[2] = SHOWA; 149 KNOWN_ERAS[3] = HEISEI; 150 for (int i = N_ERA_CONSTANTS; i < ERA_CONFIG.length; i++) { 151 CalendarDate date = ERA_CONFIG[i].getSinceDate(); 152 LocalDate isoDate = LocalDate.of(date.getYear(), date.getMonth(), date.getDayOfMonth()); 153 KNOWN_ERAS[i] = new JapaneseEra(i - ERA_OFFSET + 1, isoDate); 154 } 155 }; 156 157 /** 158 * The era value. 159 * @serial 160 */ 161 private final transient int eraValue; 162 163 // the first day of the era 164 private final transient LocalDate since; 165 166 /** 167 * Creates an instance. 168 * 169 * @param eraValue the era value, validated 170 * @param since the date representing the first date of the era, validated not null 171 */ 172 private JapaneseEra(int eraValue, LocalDate since) { 173 this.eraValue = eraValue; 174 this.since = since; 175 } 176 177 //----------------------------------------------------------------------- 178 /** 179 * Returns the Sun private Era instance corresponding to this {@code JapaneseEra}. 180 * 181 * @return the Sun private Era instance for this {@code JapaneseEra}. 182 */ 183 sun.util.calendar.Era getPrivateEra() { 184 return ERA_CONFIG[ordinal(eraValue)]; 185 } 186 187 //----------------------------------------------------------------------- 188 /** 189 * Obtains an instance of {@code JapaneseEra} from an {@code int} value. 190 * <p> 191 * The {@link #SHOWA} era that contains 1970-01-01 (ISO calendar system) has the value 1 192 * Later era is numbered 2 ({@link #HEISEI}). Earlier eras are numbered 0 ({@link #TAISHO}), 193 * -1 ({@link #MEIJI}), only Meiji and later eras are supported. 194 * 195 * @param japaneseEra the era to represent 196 * @return the {@code JapaneseEra} singleton, not null 197 * @throws DateTimeException if the value is invalid 198 */ 199 public static JapaneseEra of(int japaneseEra) { 200 int i = ordinal(japaneseEra); 201 if (i < 0 || i >= KNOWN_ERAS.length) { 202 throw new DateTimeException("Invalid era: " + japaneseEra); 203 } 204 return KNOWN_ERAS[i]; 205 } 206 207 /** 208 * Returns the {@code JapaneseEra} with the name. 209 * <p> 210 * The string must match exactly the name of the era. 211 * (Extraneous whitespace characters are not permitted.) 212 * 213 * @param japaneseEra the japaneseEra name; non-null 214 * @return the {@code JapaneseEra} singleton, never null 215 * @throws IllegalArgumentException if there is not JapaneseEra with the specified name 216 */ 217 public static JapaneseEra valueOf(String japaneseEra) { 218 Objects.requireNonNull(japaneseEra, "japaneseEra"); 219 for (JapaneseEra era : KNOWN_ERAS) { 220 if (era.getName().equals(japaneseEra)) { 221 return era; 222 } 223 } 224 throw new IllegalArgumentException("japaneseEra is invalid"); 225 } 226 227 /** 228 * Returns an array of JapaneseEras. 229 * <p> 230 * This method may be used to iterate over the JapaneseEras as follows: 231 * <pre> 232 * for (JapaneseEra c : JapaneseEra.values()) 233 * System.out.println(c); 234 * </pre> 235 * 236 * @return an array of JapaneseEras 237 */ 238 public static JapaneseEra[] values() { 239 return Arrays.copyOf(KNOWN_ERAS, KNOWN_ERAS.length); 240 } 241 242 /** 243 * {@inheritDoc} 244 * 245 * @param style {@inheritDoc} 246 * @param locale {@inheritDoc} 247 */ 248 @Override 249 public String getDisplayName(TextStyle style, Locale locale) { 250 // If this JapaneseEra is a supplemental one, obtain the name from 251 // the era definition. 252 if (getValue() > N_ERA_CONSTANTS - ERA_OFFSET) { 253 Objects.requireNonNull(locale, "locale"); 254 return style.asNormal() == TextStyle.NARROW ? getAbbreviation() : getName(); 255 } 256 return Era.super.getDisplayName(style, locale); 257 } 258 259 //----------------------------------------------------------------------- 260 /** 261 * Obtains an instance of {@code JapaneseEra} from a date. 262 * 263 * @param date the date, not null 264 * @return the Era singleton, never null 265 */ 266 static JapaneseEra from(LocalDate date) { 267 if (date.isBefore(MEIJI_6_ISODATE)) { 268 throw new DateTimeException("JapaneseDate before Meiji 6 are not supported"); 269 } 270 for (int i = KNOWN_ERAS.length - 1; i > 0; i--) { 271 JapaneseEra era = KNOWN_ERAS[i]; 272 if (date.compareTo(era.since) >= 0) { 273 return era; 274 } 275 } 276 return null; 277 } 278 279 static JapaneseEra toJapaneseEra(sun.util.calendar.Era privateEra) { 280 for (int i = ERA_CONFIG.length - 1; i >= 0; i--) { 281 if (ERA_CONFIG[i].equals(privateEra)) { 282 return KNOWN_ERAS[i]; 283 } 284 } 285 return null; 286 } 287 288 static sun.util.calendar.Era privateEraFrom(LocalDate isoDate) { 289 for (int i = KNOWN_ERAS.length - 1; i > 0; i--) { 290 JapaneseEra era = KNOWN_ERAS[i]; 291 if (isoDate.compareTo(era.since) >= 0) { 292 return ERA_CONFIG[i]; 293 } 294 } 295 return null; 296 } 297 298 /** 299 * Returns the index into the arrays from the Era value. 300 * the eraValue is a valid Era number, -1..2. 301 * 302 * @param eraValue the era value to convert to the index 303 * @return the index of the current Era 304 */ 305 private static int ordinal(int eraValue) { 306 return eraValue + ERA_OFFSET - 1; 307 } 308 309 //----------------------------------------------------------------------- 310 /** 311 * Gets the numeric era {@code int} value. 312 * <p> 313 * The {@link #SHOWA} era that contains 1970-01-01 (ISO calendar system) has the value 1. 314 * Later eras are numbered from 2 ({@link #HEISEI}). 315 * Earlier eras are numbered 0 ({@link #TAISHO}), -1 ({@link #MEIJI})). 316 * 317 * @return the era value 318 */ 319 @Override 320 public int getValue() { 321 return eraValue; 322 } 323 324 //----------------------------------------------------------------------- 325 /** 326 * Gets the range of valid values for the specified field. 327 * <p> 328 * The range object expresses the minimum and maximum valid values for a field. 329 * This era is used to enhance the accuracy of the returned range. 330 * If it is not possible to return the range, because the field is not supported 331 * or for some other reason, an exception is thrown. 332 * <p> 333 * If the field is a {@link ChronoField} then the query is implemented here. 334 * The {@code ERA} field returns the range. 335 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}. 336 * <p> 337 * If the field is not a {@code ChronoField}, then the result of this method 338 * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)} 339 * passing {@code this} as the argument. 340 * Whether the range can be obtained is determined by the field. 341 * <p> 342 * The range of valid Japanese eras can change over time due to the nature 343 * of the Japanese calendar system. 344 * 345 * @param field the field to query the range for, not null 346 * @return the range of valid values for the field, not null 347 * @throws DateTimeException if the range for the field cannot be obtained 348 * @throws UnsupportedTemporalTypeException if the unit is not supported 349 */ 350 @Override // override as super would return range from 0 to 1 351 public ValueRange range(TemporalField field) { 352 if (field == ERA) { 353 return JapaneseChronology.INSTANCE.range(ERA); 354 } 355 return Era.super.range(field); 356 } 357 358 //----------------------------------------------------------------------- 359 String getAbbreviation() { 360 return ERA_CONFIG[ordinal(getValue())].getAbbreviation(); 361 } 362 363 String getName() { 364 return ERA_CONFIG[ordinal(getValue())].getName(); 365 } 366 367 @Override 368 public String toString() { 369 return getName(); 370 } 371 372 //----------------------------------------------------------------------- 373 /** 374 * Defend against malicious streams. 375 * 376 * @param s the stream to read 377 * @throws InvalidObjectException always 378 */ 379 private void readObject(ObjectInputStream s) throws InvalidObjectException { 380 throw new InvalidObjectException("Deserialization via serialization delegate"); 381 } 382 383 //----------------------------------------------------------------------- 384 /** 385 * Writes the object using a 386 * <a href="../../../serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>. 387 * @serialData 388 * <pre> 389 * out.writeByte(5); // identifies a JapaneseEra 390 * out.writeInt(getValue()); 391 * </pre> 392 * 393 * @return the instance of {@code Ser}, not null 394 */ 395 private Object writeReplace() { 396 return new Ser(Ser.JAPANESE_ERA_TYPE, this); 397 } 398 399 void writeExternal(DataOutput out) throws IOException { 400 out.writeByte(this.getValue()); 401 } 402 403 static JapaneseEra readExternal(DataInput in) throws IOException { 404 byte eraValue = in.readByte(); 405 return JapaneseEra.of(eraValue); 406 } 407 408 }