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.temporal; 58 59 import android.icu.text.DateTimePatternGenerator; 60 import android.icu.util.ULocale; 61 import java.time.DayOfWeek; 62 import java.time.Instant; 63 import java.time.Year; 64 import java.time.ZoneOffset; 65 import java.time.chrono.ChronoLocalDate; 66 import java.time.chrono.Chronology; 67 import java.util.Locale; 68 import java.util.Objects; 69 70 import static java.time.temporal.ChronoUnit.DAYS; 71 import static java.time.temporal.ChronoUnit.ERAS; 72 import static java.time.temporal.ChronoUnit.FOREVER; 73 import static java.time.temporal.ChronoUnit.HALF_DAYS; 74 import static java.time.temporal.ChronoUnit.HOURS; 75 import static java.time.temporal.ChronoUnit.MICROS; 76 import static java.time.temporal.ChronoUnit.MILLIS; 77 import static java.time.temporal.ChronoUnit.MINUTES; 78 import static java.time.temporal.ChronoUnit.MONTHS; 79 import static java.time.temporal.ChronoUnit.NANOS; 80 import static java.time.temporal.ChronoUnit.SECONDS; 81 import static java.time.temporal.ChronoUnit.WEEKS; 82 import static java.time.temporal.ChronoUnit.YEARS; 83 84 /** 85 * A standard set of fields. 86 * <p> 87 * This set of fields provide field-based access to manipulate a date, time or date-time. 88 * The standard set of fields can be extended by implementing {@link TemporalField}. 89 * <p> 90 * These fields are intended to be applicable in multiple calendar systems. 91 * For example, most non-ISO calendar systems define dates as a year, month and day, 92 * just with slightly different rules. 93 * The documentation of each field explains how it operates. 94 * 95 * @implSpec 96 * This is a final, immutable and thread-safe enum. 97 * 98 * @since 1.8 99 */ 100 public enum ChronoField implements TemporalField { 101 102 /** 103 * The nano-of-second. 104 * <p> 105 * This counts the nanosecond within the second, from 0 to 999,999,999. 106 * This field has the same meaning for all calendar systems. 107 * <p> 108 * This field is used to represent the nano-of-second handling any fraction of the second. 109 * Implementations of {@code TemporalAccessor} should provide a value for this field if 110 * they can return a value for {@link #SECOND_OF_MINUTE}, {@link #SECOND_OF_DAY} or 111 * {@link #INSTANT_SECONDS} filling unknown precision with zero. 112 * <p> 113 * When this field is used for setting a value, it should set as much precision as the 114 * object stores, using integer division to remove excess precision. 115 * For example, if the {@code TemporalAccessor} stores time to millisecond precision, 116 * then the nano-of-second must be divided by 1,000,000 before replacing the milli-of-second. 117 * <p> 118 * When parsing this field it behaves equivalent to the following: 119 * The value is validated in strict and smart mode but not in lenient mode. 120 * The field is resolved in combination with {@code MILLI_OF_SECOND} and {@code MICRO_OF_SECOND}. 121 */ 122 NANO_OF_SECOND("NanoOfSecond", NANOS, SECONDS, ValueRange.of(0, 999_999_999)), 123 /** 124 * The nano-of-day. 125 * <p> 126 * This counts the nanosecond within the day, from 0 to (24 * 60 * 60 * 1,000,000,000) - 1. 127 * This field has the same meaning for all calendar systems. 128 * <p> 129 * This field is used to represent the nano-of-day handling any fraction of the second. 130 * Implementations of {@code TemporalAccessor} should provide a value for this field if 131 * they can return a value for {@link #SECOND_OF_DAY} filling unknown precision with zero. 132 * <p> 133 * When parsing this field it behaves equivalent to the following: 134 * The value is validated in strict and smart mode but not in lenient mode. 135 * The value is split to form {@code NANO_OF_SECOND}, {@code SECOND_OF_MINUTE}, 136 * {@code MINUTE_OF_HOUR} and {@code HOUR_OF_DAY} fields. 137 */ 138 NANO_OF_DAY("NanoOfDay", NANOS, DAYS, ValueRange.of(0, 86400L * 1000_000_000L - 1)), 139 /** 140 * The micro-of-second. 141 * <p> 142 * This counts the microsecond within the second, from 0 to 999,999. 143 * This field has the same meaning for all calendar systems. 144 * <p> 145 * This field is used to represent the micro-of-second handling any fraction of the second. 146 * Implementations of {@code TemporalAccessor} should provide a value for this field if 147 * they can return a value for {@link #SECOND_OF_MINUTE}, {@link #SECOND_OF_DAY} or 148 * {@link #INSTANT_SECONDS} filling unknown precision with zero. 149 * <p> 150 * When this field is used for setting a value, it should behave in the same way as 151 * setting {@link #NANO_OF_SECOND} with the value multiplied by 1,000. 152 * <p> 153 * When parsing this field it behaves equivalent to the following: 154 * The value is validated in strict and smart mode but not in lenient mode. 155 * The field is resolved in combination with {@code MILLI_OF_SECOND} to produce 156 * {@code NANO_OF_SECOND}. 157 */ 158 MICRO_OF_SECOND("MicroOfSecond", MICROS, SECONDS, ValueRange.of(0, 999_999)), 159 /** 160 * The micro-of-day. 161 * <p> 162 * This counts the microsecond within the day, from 0 to (24 * 60 * 60 * 1,000,000) - 1. 163 * This field has the same meaning for all calendar systems. 164 * <p> 165 * This field is used to represent the micro-of-day handling any fraction of the second. 166 * Implementations of {@code TemporalAccessor} should provide a value for this field if 167 * they can return a value for {@link #SECOND_OF_DAY} filling unknown precision with zero. 168 * <p> 169 * When this field is used for setting a value, it should behave in the same way as 170 * setting {@link #NANO_OF_DAY} with the value multiplied by 1,000. 171 * <p> 172 * When parsing this field it behaves equivalent to the following: 173 * The value is validated in strict and smart mode but not in lenient mode. 174 * The value is split to form {@code MICRO_OF_SECOND}, {@code SECOND_OF_MINUTE}, 175 * {@code MINUTE_OF_HOUR} and {@code HOUR_OF_DAY} fields. 176 */ 177 MICRO_OF_DAY("MicroOfDay", MICROS, DAYS, ValueRange.of(0, 86400L * 1000_000L - 1)), 178 /** 179 * The milli-of-second. 180 * <p> 181 * This counts the millisecond within the second, from 0 to 999. 182 * This field has the same meaning for all calendar systems. 183 * <p> 184 * This field is used to represent the milli-of-second handling any fraction of the second. 185 * Implementations of {@code TemporalAccessor} should provide a value for this field if 186 * they can return a value for {@link #SECOND_OF_MINUTE}, {@link #SECOND_OF_DAY} or 187 * {@link #INSTANT_SECONDS} filling unknown precision with zero. 188 * <p> 189 * When this field is used for setting a value, it should behave in the same way as 190 * setting {@link #NANO_OF_SECOND} with the value multiplied by 1,000,000. 191 * <p> 192 * When parsing this field it behaves equivalent to the following: 193 * The value is validated in strict and smart mode but not in lenient mode. 194 * The field is resolved in combination with {@code MICRO_OF_SECOND} to produce 195 * {@code NANO_OF_SECOND}. 196 */ 197 MILLI_OF_SECOND("MilliOfSecond", MILLIS, SECONDS, ValueRange.of(0, 999)), 198 /** 199 * The milli-of-day. 200 * <p> 201 * This counts the millisecond within the day, from 0 to (24 * 60 * 60 * 1,000) - 1. 202 * This field has the same meaning for all calendar systems. 203 * <p> 204 * This field is used to represent the milli-of-day handling any fraction of the second. 205 * Implementations of {@code TemporalAccessor} should provide a value for this field if 206 * they can return a value for {@link #SECOND_OF_DAY} filling unknown precision with zero. 207 * <p> 208 * When this field is used for setting a value, it should behave in the same way as 209 * setting {@link #NANO_OF_DAY} with the value multiplied by 1,000,000. 210 * <p> 211 * When parsing this field it behaves equivalent to the following: 212 * The value is validated in strict and smart mode but not in lenient mode. 213 * The value is split to form {@code MILLI_OF_SECOND}, {@code SECOND_OF_MINUTE}, 214 * {@code MINUTE_OF_HOUR} and {@code HOUR_OF_DAY} fields. 215 */ 216 MILLI_OF_DAY("MilliOfDay", MILLIS, DAYS, ValueRange.of(0, 86400L * 1000L - 1)), 217 /** 218 * The second-of-minute. 219 * <p> 220 * This counts the second within the minute, from 0 to 59. 221 * This field has the same meaning for all calendar systems. 222 * <p> 223 * When parsing this field it behaves equivalent to the following: 224 * The value is validated in strict and smart mode but not in lenient mode. 225 */ 226 SECOND_OF_MINUTE("SecondOfMinute", SECONDS, MINUTES, ValueRange.of(0, 59), "second"), 227 /** 228 * The second-of-day. 229 * <p> 230 * This counts the second within the day, from 0 to (24 * 60 * 60) - 1. 231 * This field has the same meaning for all calendar systems. 232 * <p> 233 * When parsing this field it behaves equivalent to the following: 234 * The value is validated in strict and smart mode but not in lenient mode. 235 * The value is split to form {@code SECOND_OF_MINUTE}, {@code MINUTE_OF_HOUR} 236 * and {@code HOUR_OF_DAY} fields. 237 */ 238 SECOND_OF_DAY("SecondOfDay", SECONDS, DAYS, ValueRange.of(0, 86400L - 1)), 239 /** 240 * The minute-of-hour. 241 * <p> 242 * This counts the minute within the hour, from 0 to 59. 243 * This field has the same meaning for all calendar systems. 244 * <p> 245 * When parsing this field it behaves equivalent to the following: 246 * The value is validated in strict and smart mode but not in lenient mode. 247 */ 248 MINUTE_OF_HOUR("MinuteOfHour", MINUTES, HOURS, ValueRange.of(0, 59), "minute"), 249 /** 250 * The minute-of-day. 251 * <p> 252 * This counts the minute within the day, from 0 to (24 * 60) - 1. 253 * This field has the same meaning for all calendar systems. 254 * <p> 255 * When parsing this field it behaves equivalent to the following: 256 * The value is validated in strict and smart mode but not in lenient mode. 257 * The value is split to form {@code MINUTE_OF_HOUR} and {@code HOUR_OF_DAY} fields. 258 */ 259 MINUTE_OF_DAY("MinuteOfDay", MINUTES, DAYS, ValueRange.of(0, (24 * 60) - 1)), 260 /** 261 * The hour-of-am-pm. 262 * <p> 263 * This counts the hour within the AM/PM, from 0 to 11. 264 * This is the hour that would be observed on a standard 12-hour digital clock. 265 * This field has the same meaning for all calendar systems. 266 * <p> 267 * When parsing this field it behaves equivalent to the following: 268 * The value is validated from 0 to 11 in strict and smart mode. 269 * In lenient mode the value is not validated. It is combined with 270 * {@code AMPM_OF_DAY} to form {@code HOUR_OF_DAY} by multiplying 271 * the {AMPM_OF_DAY} value by 12. 272 */ 273 HOUR_OF_AMPM("HourOfAmPm", HOURS, HALF_DAYS, ValueRange.of(0, 11)), 274 /** 275 * The clock-hour-of-am-pm. 276 * <p> 277 * This counts the hour within the AM/PM, from 1 to 12. 278 * This is the hour that would be observed on a standard 12-hour analog wall clock. 279 * This field has the same meaning for all calendar systems. 280 * <p> 281 * When parsing this field it behaves equivalent to the following: 282 * The value is validated from 1 to 12 in strict mode and from 283 * 0 to 12 in smart mode. In lenient mode the value is not validated. 284 * The field is converted to an {@code HOUR_OF_AMPM} with the same value, 285 * unless the value is 12, in which case it is converted to 0. 286 */ 287 CLOCK_HOUR_OF_AMPM("ClockHourOfAmPm", HOURS, HALF_DAYS, ValueRange.of(1, 12)), 288 /** 289 * The hour-of-day. 290 * <p> 291 * This counts the hour within the day, from 0 to 23. 292 * This is the hour that would be observed on a standard 24-hour digital clock. 293 * This field has the same meaning for all calendar systems. 294 * <p> 295 * When parsing this field it behaves equivalent to the following: 296 * The value is validated in strict and smart mode but not in lenient mode. 297 * The field is combined with {@code MINUTE_OF_HOUR}, {@code SECOND_OF_MINUTE} and 298 * {@code NANO_OF_SECOND} to produce a {@code LocalTime}. 299 * In lenient mode, any excess days are added to the parsed date, or 300 * made available via {@link java.time.format.DateTimeFormatter#parsedExcessDays()}. 301 */ 302 HOUR_OF_DAY("HourOfDay", HOURS, DAYS, ValueRange.of(0, 23), "hour"), 303 /** 304 * The clock-hour-of-day. 305 * <p> 306 * This counts the hour within the AM/PM, from 1 to 24. 307 * This is the hour that would be observed on a 24-hour analog wall clock. 308 * This field has the same meaning for all calendar systems. 309 * <p> 310 * When parsing this field it behaves equivalent to the following: 311 * The value is validated from 1 to 24 in strict mode and from 312 * 0 to 24 in smart mode. In lenient mode the value is not validated. 313 * The field is converted to an {@code HOUR_OF_DAY} with the same value, 314 * unless the value is 24, in which case it is converted to 0. 315 */ 316 CLOCK_HOUR_OF_DAY("ClockHourOfDay", HOURS, DAYS, ValueRange.of(1, 24)), 317 /** 318 * The am-pm-of-day. 319 * <p> 320 * This counts the AM/PM within the day, from 0 (AM) to 1 (PM). 321 * This field has the same meaning for all calendar systems. 322 * <p> 323 * When parsing this field it behaves equivalent to the following: 324 * The value is validated from 0 to 1 in strict and smart mode. 325 * In lenient mode the value is not validated. It is combined with 326 * {@code HOUR_OF_AMPM} to form {@code HOUR_OF_DAY} by multiplying 327 * the {AMPM_OF_DAY} value by 12. 328 */ 329 AMPM_OF_DAY("AmPmOfDay", HALF_DAYS, DAYS, ValueRange.of(0, 1), "dayperiod"), 330 /** 331 * The day-of-week, such as Tuesday. 332 * <p> 333 * This represents the standard concept of the day of the week. 334 * In the default ISO calendar system, this has values from Monday (1) to Sunday (7). 335 * The {@link DayOfWeek} class can be used to interpret the result. 336 * <p> 337 * Most non-ISO calendar systems also define a seven day week that aligns with ISO. 338 * Those calendar systems must also use the same numbering system, from Monday (1) to 339 * Sunday (7), which allows {@code DayOfWeek} to be used. 340 * <p> 341 * Calendar systems that do not have a standard seven day week should implement this field 342 * if they have a similar concept of named or numbered days within a period similar 343 * to a week. It is recommended that the numbering starts from 1. 344 */ 345 DAY_OF_WEEK("DayOfWeek", DAYS, WEEKS, ValueRange.of(1, 7), "weekday"), 346 /** 347 * The aligned day-of-week within a month. 348 * <p> 349 * This represents concept of the count of days within the period of a week 350 * where the weeks are aligned to the start of the month. 351 * This field is typically used with {@link #ALIGNED_WEEK_OF_MONTH}. 352 * <p> 353 * For example, in a calendar systems with a seven day week, the first aligned-week-of-month 354 * starts on day-of-month 1, the second aligned-week starts on day-of-month 8, and so on. 355 * Within each of these aligned-weeks, the days are numbered from 1 to 7 and returned 356 * as the value of this field. 357 * As such, day-of-month 1 to 7 will have aligned-day-of-week values from 1 to 7. 358 * And day-of-month 8 to 14 will repeat this with aligned-day-of-week values from 1 to 7. 359 * <p> 360 * Calendar systems that do not have a seven day week should typically implement this 361 * field in the same way, but using the alternate week length. 362 */ 363 ALIGNED_DAY_OF_WEEK_IN_MONTH("AlignedDayOfWeekInMonth", DAYS, WEEKS, ValueRange.of(1, 7)), 364 /** 365 * The aligned day-of-week within a year. 366 * <p> 367 * This represents concept of the count of days within the period of a week 368 * where the weeks are aligned to the start of the year. 369 * This field is typically used with {@link #ALIGNED_WEEK_OF_YEAR}. 370 * <p> 371 * For example, in a calendar systems with a seven day week, the first aligned-week-of-year 372 * starts on day-of-year 1, the second aligned-week starts on day-of-year 8, and so on. 373 * Within each of these aligned-weeks, the days are numbered from 1 to 7 and returned 374 * as the value of this field. 375 * As such, day-of-year 1 to 7 will have aligned-day-of-week values from 1 to 7. 376 * And day-of-year 8 to 14 will repeat this with aligned-day-of-week values from 1 to 7. 377 * <p> 378 * Calendar systems that do not have a seven day week should typically implement this 379 * field in the same way, but using the alternate week length. 380 */ 381 ALIGNED_DAY_OF_WEEK_IN_YEAR("AlignedDayOfWeekInYear", DAYS, WEEKS, ValueRange.of(1, 7)), 382 /** 383 * The day-of-month. 384 * <p> 385 * This represents the concept of the day within the month. 386 * In the default ISO calendar system, this has values from 1 to 31 in most months. 387 * April, June, September, November have days from 1 to 30, while February has days 388 * from 1 to 28, or 29 in a leap year. 389 * <p> 390 * Non-ISO calendar systems should implement this field using the most recognized 391 * day-of-month values for users of the calendar system. 392 * Normally, this is a count of days from 1 to the length of the month. 393 */ 394 DAY_OF_MONTH("DayOfMonth", DAYS, MONTHS, ValueRange.of(1, 28, 31), "day"), 395 /** 396 * The day-of-year. 397 * <p> 398 * This represents the concept of the day within the year. 399 * In the default ISO calendar system, this has values from 1 to 365 in standard 400 * years and 1 to 366 in leap years. 401 * <p> 402 * Non-ISO calendar systems should implement this field using the most recognized 403 * day-of-year values for users of the calendar system. 404 * Normally, this is a count of days from 1 to the length of the year. 405 * <p> 406 * Note that a non-ISO calendar system may have year numbering system that changes 407 * at a different point to the natural reset in the month numbering. An example 408 * of this is the Japanese calendar system where a change of era, which resets 409 * the year number to 1, can happen on any date. The era and year reset also cause 410 * the day-of-year to be reset to 1, but not the month-of-year or day-of-month. 411 */ 412 DAY_OF_YEAR("DayOfYear", DAYS, YEARS, ValueRange.of(1, 365, 366)), 413 /** 414 * The epoch-day, based on the Java epoch of 1970-01-01 (ISO). 415 * <p> 416 * This field is the sequential count of days where 1970-01-01 (ISO) is zero. 417 * Note that this uses the <i>local</i> time-line, ignoring offset and time-zone. 418 * <p> 419 * This field is strictly defined to have the same meaning in all calendar systems. 420 * This is necessary to ensure interoperation between calendars. 421 */ 422 EPOCH_DAY("EpochDay", DAYS, FOREVER, ValueRange.of((long) (Year.MIN_VALUE * 365.25), (long) (Year.MAX_VALUE * 365.25))), 423 /** 424 * The aligned week within a month. 425 * <p> 426 * This represents concept of the count of weeks within the period of a month 427 * where the weeks are aligned to the start of the month. 428 * This field is typically used with {@link #ALIGNED_DAY_OF_WEEK_IN_MONTH}. 429 * <p> 430 * For example, in a calendar systems with a seven day week, the first aligned-week-of-month 431 * starts on day-of-month 1, the second aligned-week starts on day-of-month 8, and so on. 432 * Thus, day-of-month values 1 to 7 are in aligned-week 1, while day-of-month values 433 * 8 to 14 are in aligned-week 2, and so on. 434 * <p> 435 * Calendar systems that do not have a seven day week should typically implement this 436 * field in the same way, but using the alternate week length. 437 */ 438 ALIGNED_WEEK_OF_MONTH("AlignedWeekOfMonth", WEEKS, MONTHS, ValueRange.of(1, 4, 5)), 439 /** 440 * The aligned week within a year. 441 * <p> 442 * This represents concept of the count of weeks within the period of a year 443 * where the weeks are aligned to the start of the year. 444 * This field is typically used with {@link #ALIGNED_DAY_OF_WEEK_IN_YEAR}. 445 * <p> 446 * For example, in a calendar systems with a seven day week, the first aligned-week-of-year 447 * starts on day-of-year 1, the second aligned-week starts on day-of-year 8, and so on. 448 * Thus, day-of-year values 1 to 7 are in aligned-week 1, while day-of-year values 449 * 8 to 14 are in aligned-week 2, and so on. 450 * <p> 451 * Calendar systems that do not have a seven day week should typically implement this 452 * field in the same way, but using the alternate week length. 453 */ 454 ALIGNED_WEEK_OF_YEAR("AlignedWeekOfYear", WEEKS, YEARS, ValueRange.of(1, 53)), 455 /** 456 * The month-of-year, such as March. 457 * <p> 458 * This represents the concept of the month within the year. 459 * In the default ISO calendar system, this has values from January (1) to December (12). 460 * <p> 461 * Non-ISO calendar systems should implement this field using the most recognized 462 * month-of-year values for users of the calendar system. 463 * Normally, this is a count of months starting from 1. 464 */ 465 MONTH_OF_YEAR("MonthOfYear", MONTHS, YEARS, ValueRange.of(1, 12), "month"), 466 /** 467 * The proleptic-month based, counting months sequentially from year 0. 468 * <p> 469 * This field is the sequential count of months where the first month 470 * in proleptic-year zero has the value zero. 471 * Later months have increasingly larger values. 472 * Earlier months have increasingly small values. 473 * There are no gaps or breaks in the sequence of months. 474 * Note that this uses the <i>local</i> time-line, ignoring offset and time-zone. 475 * <p> 476 * In the default ISO calendar system, June 2012 would have the value 477 * {@code (2012 * 12 + 6 - 1)}. This field is primarily for internal use. 478 * <p> 479 * Non-ISO calendar systems must implement this field as per the definition above. 480 * It is just a simple zero-based count of elapsed months from the start of proleptic-year 0. 481 * All calendar systems with a full proleptic-year definition will have a year zero. 482 * If the calendar system has a minimum year that excludes year zero, then one must 483 * be extrapolated in order for this method to be defined. 484 */ 485 PROLEPTIC_MONTH("ProlepticMonth", MONTHS, FOREVER, ValueRange.of(Year.MIN_VALUE * 12L, Year.MAX_VALUE * 12L + 11)), 486 /** 487 * The year within the era. 488 * <p> 489 * This represents the concept of the year within the era. 490 * This field is typically used with {@link #ERA}. 491 * <p> 492 * The standard mental model for a date is based on three concepts - year, month and day. 493 * These map onto the {@code YEAR}, {@code MONTH_OF_YEAR} and {@code DAY_OF_MONTH} fields. 494 * Note that there is no reference to eras. 495 * The full model for a date requires four concepts - era, year, month and day. These map onto 496 * the {@code ERA}, {@code YEAR_OF_ERA}, {@code MONTH_OF_YEAR} and {@code DAY_OF_MONTH} fields. 497 * Whether this field or {@code YEAR} is used depends on which mental model is being used. 498 * See {@link ChronoLocalDate} for more discussion on this topic. 499 * <p> 500 * In the default ISO calendar system, there are two eras defined, 'BCE' and 'CE'. 501 * The era 'CE' is the one currently in use and year-of-era runs from 1 to the maximum value. 502 * The era 'BCE' is the previous era, and the year-of-era runs backwards. 503 * <p> 504 * For example, subtracting a year each time yield the following:<br> 505 * - year-proleptic 2 = 'CE' year-of-era 2<br> 506 * - year-proleptic 1 = 'CE' year-of-era 1<br> 507 * - year-proleptic 0 = 'BCE' year-of-era 1<br> 508 * - year-proleptic -1 = 'BCE' year-of-era 2<br> 509 * <p> 510 * Note that the ISO-8601 standard does not actually define eras. 511 * Note also that the ISO eras do not align with the well-known AD/BC eras due to the 512 * change between the Julian and Gregorian calendar systems. 513 * <p> 514 * Non-ISO calendar systems should implement this field using the most recognized 515 * year-of-era value for users of the calendar system. 516 * Since most calendar systems have only two eras, the year-of-era numbering approach 517 * will typically be the same as that used by the ISO calendar system. 518 * The year-of-era value should typically always be positive, however this is not required. 519 */ 520 YEAR_OF_ERA("YearOfEra", YEARS, FOREVER, ValueRange.of(1, Year.MAX_VALUE, Year.MAX_VALUE + 1)), 521 /** 522 * The proleptic year, such as 2012. 523 * <p> 524 * This represents the concept of the year, counting sequentially and using negative numbers. 525 * The proleptic year is not interpreted in terms of the era. 526 * See {@link #YEAR_OF_ERA} for an example showing the mapping from proleptic year to year-of-era. 527 * <p> 528 * The standard mental model for a date is based on three concepts - year, month and day. 529 * These map onto the {@code YEAR}, {@code MONTH_OF_YEAR} and {@code DAY_OF_MONTH} fields. 530 * Note that there is no reference to eras. 531 * The full model for a date requires four concepts - era, year, month and day. These map onto 532 * the {@code ERA}, {@code YEAR_OF_ERA}, {@code MONTH_OF_YEAR} and {@code DAY_OF_MONTH} fields. 533 * Whether this field or {@code YEAR_OF_ERA} is used depends on which mental model is being used. 534 * See {@link ChronoLocalDate} for more discussion on this topic. 535 * <p> 536 * Non-ISO calendar systems should implement this field as follows. 537 * If the calendar system has only two eras, before and after a fixed date, then the 538 * proleptic-year value must be the same as the year-of-era value for the later era, 539 * and increasingly negative for the earlier era. 540 * If the calendar system has more than two eras, then the proleptic-year value may be 541 * defined with any appropriate value, although defining it to be the same as ISO may be 542 * the best option. 543 */ 544 YEAR("Year", YEARS, FOREVER, ValueRange.of(Year.MIN_VALUE, Year.MAX_VALUE), "year"), 545 /** 546 * The era. 547 * <p> 548 * This represents the concept of the era, which is the largest division of the time-line. 549 * This field is typically used with {@link #YEAR_OF_ERA}. 550 * <p> 551 * In the default ISO calendar system, there are two eras defined, 'BCE' and 'CE'. 552 * The era 'CE' is the one currently in use and year-of-era runs from 1 to the maximum value. 553 * The era 'BCE' is the previous era, and the year-of-era runs backwards. 554 * See {@link #YEAR_OF_ERA} for a full example. 555 * <p> 556 * Non-ISO calendar systems should implement this field to define eras. 557 * The value of the era that was active on 1970-01-01 (ISO) must be assigned the value 1. 558 * Earlier eras must have sequentially smaller values. 559 * Later eras must have sequentially larger values, 560 */ 561 ERA("Era", ERAS, FOREVER, ValueRange.of(0, 1), "era"), 562 /** 563 * The instant epoch-seconds. 564 * <p> 565 * This represents the concept of the sequential count of seconds where 566 * 1970-01-01T00:00Z (ISO) is zero. 567 * This field may be used with {@link #NANO_OF_SECOND} to represent the fraction of the second. 568 * <p> 569 * An {@link Instant} represents an instantaneous point on the time-line. 570 * On their own, an instant has insufficient information to allow a local date-time to be obtained. 571 * Only when paired with an offset or time-zone can the local date or time be calculated. 572 * <p> 573 * This field is strictly defined to have the same meaning in all calendar systems. 574 * This is necessary to ensure interoperation between calendars. 575 */ 576 INSTANT_SECONDS("InstantSeconds", SECONDS, FOREVER, ValueRange.of(Long.MIN_VALUE, Long.MAX_VALUE)), 577 /** 578 * The offset from UTC/Greenwich. 579 * <p> 580 * This represents the concept of the offset in seconds of local time from UTC/Greenwich. 581 * <p> 582 * A {@link ZoneOffset} represents the period of time that local time differs from UTC/Greenwich. 583 * This is usually a fixed number of hours and minutes. 584 * It is equivalent to the {@link ZoneOffset#getTotalSeconds() total amount} of the offset in seconds. 585 * For example, during the winter Paris has an offset of {@code +01:00}, which is 3600 seconds. 586 * <p> 587 * This field is strictly defined to have the same meaning in all calendar systems. 588 * This is necessary to ensure interoperation between calendars. 589 */ 590 OFFSET_SECONDS("OffsetSeconds", SECONDS, FOREVER, ValueRange.of(-18 * 3600, 18 * 3600)); 591 592 private final String name; 593 private final TemporalUnit baseUnit; 594 private final TemporalUnit rangeUnit; 595 private final ValueRange range; 596 private final String displayNameKey; 597 598 private ChronoField(String name, TemporalUnit baseUnit, TemporalUnit rangeUnit, ValueRange range) { 599 this.name = name; 600 this.baseUnit = baseUnit; 601 this.rangeUnit = rangeUnit; 602 this.range = range; 603 this.displayNameKey = null; 604 } 605 606 private ChronoField(String name, TemporalUnit baseUnit, TemporalUnit rangeUnit, 607 ValueRange range, String displayNameKey) { 608 this.name = name; 609 this.baseUnit = baseUnit; 610 this.rangeUnit = rangeUnit; 611 this.range = range; 612 this.displayNameKey = displayNameKey; 613 } 614 615 @Override 616 public String getDisplayName(Locale locale) { 617 Objects.requireNonNull(locale, "locale"); 618 if (displayNameKey == null) { 619 return name; 620 } 621 622 // Android-changed: use ICU names. 623 DateTimePatternGenerator generator = DateTimePatternGenerator 624 .getFrozenInstance(ULocale.forLocale(locale)); 625 String icuName = generator.getAppendItemName(getIcuFieldNumber(this)); 626 return icuName != null && !icuName.isEmpty() ? icuName : name; 627 } 628 629 /** 630 * @return the field id according to {@link DateTimePatternGenerator} for the field. 631 */ 632 private static int getIcuFieldNumber(ChronoField field) { 633 switch (field) { 634 case SECOND_OF_MINUTE: 635 return DateTimePatternGenerator.SECOND; 636 case MINUTE_OF_HOUR: 637 return DateTimePatternGenerator.MINUTE; 638 case HOUR_OF_DAY: 639 return DateTimePatternGenerator.HOUR; 640 case AMPM_OF_DAY: 641 return DateTimePatternGenerator.DAYPERIOD; 642 case DAY_OF_WEEK: 643 return DateTimePatternGenerator.WEEKDAY; 644 case DAY_OF_MONTH: 645 return DateTimePatternGenerator.DAY; 646 case MONTH_OF_YEAR: 647 return DateTimePatternGenerator.MONTH; 648 case YEAR: 649 return DateTimePatternGenerator.YEAR; 650 case ERA: 651 return DateTimePatternGenerator.ERA; 652 default: 653 throw new IllegalArgumentException("Unexpected ChronoField " + field.name()); 654 } 655 } 656 657 @Override 658 public TemporalUnit getBaseUnit() { 659 return baseUnit; 660 } 661 662 @Override 663 public TemporalUnit getRangeUnit() { 664 return rangeUnit; 665 } 666 667 /** 668 * Gets the range of valid values for the field. 669 * <p> 670 * All fields can be expressed as a {@code long} integer. 671 * This method returns an object that describes the valid range for that value. 672 * <p> 673 * This method returns the range of the field in the ISO-8601 calendar system. 674 * This range may be incorrect for other calendar systems. 675 * Use {@link Chronology#range(ChronoField)} to access the correct range 676 * for a different calendar system. 677 * <p> 678 * Note that the result only describes the minimum and maximum valid values 679 * and it is important not to read too much into them. For example, there 680 * could be values within the range that are invalid for the field. 681 * 682 * @return the range of valid values for the field, not null 683 */ 684 @Override 685 public ValueRange range() { 686 return range; 687 } 688 689 //----------------------------------------------------------------------- 690 /** 691 * Checks if this field represents a component of a date. 692 * <p> 693 * Fields from day-of-week to era are date-based. 694 * 695 * @return true if it is a component of a date 696 */ 697 @Override 698 public boolean isDateBased() { 699 return ordinal() >= DAY_OF_WEEK.ordinal() && ordinal() <= ERA.ordinal(); 700 } 701 702 /** 703 * Checks if this field represents a component of a time. 704 * <p> 705 * Fields from nano-of-second to am-pm-of-day are time-based. 706 * 707 * @return true if it is a component of a time 708 */ 709 @Override 710 public boolean isTimeBased() { 711 return ordinal() < DAY_OF_WEEK.ordinal(); 712 } 713 714 //----------------------------------------------------------------------- 715 /** 716 * Checks that the specified value is valid for this field. 717 * <p> 718 * This validates that the value is within the outer range of valid values 719 * returned by {@link #range()}. 720 * <p> 721 * This method checks against the range of the field in the ISO-8601 calendar system. 722 * This range may be incorrect for other calendar systems. 723 * Use {@link Chronology#range(ChronoField)} to access the correct range 724 * for a different calendar system. 725 * 726 * @param value the value to check 727 * @return the value that was passed in 728 */ 729 public long checkValidValue(long value) { 730 return range().checkValidValue(value, this); 731 } 732 733 /** 734 * Checks that the specified value is valid and fits in an {@code int}. 735 * <p> 736 * This validates that the value is within the outer range of valid values 737 * returned by {@link #range()}. 738 * It also checks that all valid values are within the bounds of an {@code int}. 739 * <p> 740 * This method checks against the range of the field in the ISO-8601 calendar system. 741 * This range may be incorrect for other calendar systems. 742 * Use {@link Chronology#range(ChronoField)} to access the correct range 743 * for a different calendar system. 744 * 745 * @param value the value to check 746 * @return the value that was passed in 747 */ 748 public int checkValidIntValue(long value) { 749 return range().checkValidIntValue(value, this); 750 } 751 752 //----------------------------------------------------------------------- 753 @Override 754 public boolean isSupportedBy(TemporalAccessor temporal) { 755 return temporal.isSupported(this); 756 } 757 758 @Override 759 public ValueRange rangeRefinedBy(TemporalAccessor temporal) { 760 return temporal.range(this); 761 } 762 763 @Override 764 public long getFrom(TemporalAccessor temporal) { 765 return temporal.getLong(this); 766 } 767 768 @SuppressWarnings("unchecked") 769 @Override 770 public <R extends Temporal> R adjustInto(R temporal, long newValue) { 771 return (R) temporal.with(this, newValue); 772 } 773 774 //----------------------------------------------------------------------- 775 @Override 776 public String toString() { 777 return name; 778 } 779 780 } 781
