-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathChronology.java
More file actions
753 lines (718 loc) · 32.8 KB
/
Chronology.java
File metadata and controls
753 lines (718 loc) · 32.8 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
/*
* Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
/*
*
*
*
*
*
* Copyright (c) 2012, Stephen Colebourne & Michael Nascimento Santos
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of JSR-310 nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package java.time.chrono;
import java.time.Clock;
import java.time.DateTimeException;
import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatterBuilder;
import java.time.format.ResolverStyle;
import java.time.format.TextStyle;
import java.time.temporal.ChronoField;
import java.time.temporal.TemporalAccessor;
import java.time.temporal.TemporalField;
import java.time.temporal.TemporalQueries;
import java.time.temporal.TemporalQuery;
import java.time.temporal.UnsupportedTemporalTypeException;
import java.time.temporal.ValueRange;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
/**
* A calendar system, used to organize and identify dates.
* <p>
* The main date and time API is built on the ISO calendar system.
* The chronology operates behind the scenes to represent the general concept of a calendar system.
* For example, the Japanese, Minguo, Thai Buddhist and others.
* <p>
* Most other calendar systems also operate on the shared concepts of year, month and day,
* linked to the cycles of the Earth around the Sun, and the Moon around the Earth.
* These shared concepts are defined by {@link ChronoField} and are available
* for use by any {@code Chronology} implementation:
* <pre>
* LocalDate isoDate = ...
* ThaiBuddhistDate thaiDate = ...
* int isoYear = isoDate.get(ChronoField.YEAR);
* int thaiYear = thaiDate.get(ChronoField.YEAR);
* </pre>
* As shown, although the date objects are in different calendar systems, represented by different
* {@code Chronology} instances, both can be queried using the same constant on {@code ChronoField}.
* For a full discussion of the implications of this, see {@link ChronoLocalDate}.
* In general, the advice is to use the known ISO-based {@code LocalDate}, rather than
* {@code ChronoLocalDate}.
* <p>
* While a {@code Chronology} object typically uses {@code ChronoField} and is based on
* an era, year-of-era, month-of-year, day-of-month model of a date, this is not required.
* A {@code Chronology} instance may represent a totally different kind of calendar system,
* such as the Mayan.
* <p>
* In practical terms, the {@code Chronology} instance also acts as a factory.
* The {@link #of(String)} method allows an instance to be looked up by identifier,
* while the {@link #ofLocale(Locale)} method allows lookup by locale.
* <p>
* The {@code Chronology} instance provides a set of methods to create {@code ChronoLocalDate} instances.
* The date classes are used to manipulate specific dates.
* <ul>
* <li> {@link #dateNow() dateNow()}
* <li> {@link #dateNow(Clock) dateNow(clock)}
* <li> {@link #dateNow(ZoneId) dateNow(zone)}
* <li> {@link #date(int, int, int) date(yearProleptic, month, day)}
* <li> {@link #date(Era, int, int, int) date(era, yearOfEra, month, day)}
* <li> {@link #dateYearDay(int, int) dateYearDay(yearProleptic, dayOfYear)}
* <li> {@link #dateYearDay(Era, int, int) dateYearDay(era, yearOfEra, dayOfYear)}
* <li> {@link #date(TemporalAccessor) date(TemporalAccessor)}
* </ul>
*
* <h3 id="addcalendars">Adding New Calendars</h3>
* The set of available chronologies can be extended by applications.
* Adding a new calendar system requires the writing of an implementation of
* {@code Chronology}, {@code ChronoLocalDate} and {@code Era}.
* The majority of the logic specific to the calendar system will be in
* {@code ChronoLocalDate}. The {@code Chronology} subclass acts as a factory.
* <p>
* To permit the discovery of additional chronologies, the {@link java.util.ServiceLoader ServiceLoader}
* is used. A file must be added to the {@code META-INF/services} directory with the
* name 'java.time.chrono.Chronology' listing the implementation classes.
* See the ServiceLoader for more details on service loading.
* For lookup by id or calendarType, the system provided calendars are found
* first followed by application provided calendars.
* <p>
* Each chronology must define a chronology ID that is unique within the system.
* If the chronology represents a calendar system defined by the
* CLDR specification then the calendar type is the concatenation of the
* CLDR type and, if applicable, the CLDR variant,
*
* @implSpec
* This interface must be implemented with care to ensure other classes operate correctly.
* All implementations that can be instantiated must be final, immutable and thread-safe.
* Subclasses should be Serializable wherever possible.
*
* @since 1.8
*/
public interface Chronology extends Comparable<Chronology> {
/**
* Obtains an instance of {@code Chronology} from a temporal object.
* <p>
* This obtains a chronology based on the specified temporal.
* A {@code TemporalAccessor} represents an arbitrary set of date and time information,
* which this factory converts to an instance of {@code Chronology}.
* <p>
* The conversion will obtain the chronology using {@link TemporalQueries#chronology()}.
* If the specified temporal object does not have a chronology, {@link IsoChronology} is returned.
* <p>
* This method matches the signature of the functional interface {@link TemporalQuery}
* allowing it to be used in queries via method reference, {@code Chronology::from}.
*
* @param temporal the temporal to convert, not null
* @return the chronology, not null
* @throws DateTimeException if unable to convert to an {@code Chronology}
*/
static Chronology from(TemporalAccessor temporal) {
Objects.requireNonNull(temporal, "temporal");
Chronology obj = temporal.query(TemporalQueries.chronology());
return (obj != null ? obj : IsoChronology.INSTANCE);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code Chronology} from a locale.
* <p>
* This returns a {@code Chronology} based on the specified locale,
* typically returning {@code IsoChronology}. Other calendar systems
* are only returned if they are explicitly selected within the locale.
* <p>
* The {@link Locale} class provide access to a range of information useful
* for localizing an application. This includes the language and region,
* such as "en-GB" for English as used in Great Britain.
* <p>
* The {@code Locale} class also supports an extension mechanism that
* can be used to identify a calendar system. The mechanism is a form
* of key-value pairs, where the calendar system has the key "ca".
* For example, the locale "en-JP-u-ca-japanese" represents the English
* language as used in Japan with the Japanese calendar system.
* <p>
* This method finds the desired calendar system by in a manner equivalent
* to passing "ca" to {@link Locale#getUnicodeLocaleType(String)}.
* If the "ca" key is not present, then {@code IsoChronology} is returned.
* <p>
* Note that the behavior of this method differs from the older
* {@link java.util.Calendar#getInstance(Locale)} method.
* If that method receives a locale of "th_TH" it will return {@code BuddhistCalendar}.
* By contrast, this method will return {@code IsoChronology}.
* Passing the locale "th-TH-u-ca-buddhist" into either method will
* result in the Thai Buddhist calendar system and is therefore the
* recommended approach going forward for Thai calendar system localization.
* <p>
* A similar, but simpler, situation occurs for the Japanese calendar system.
* The locale "jp_JP_JP" has previously been used to access the calendar.
* However, unlike the Thai locale, "ja_JP_JP" is automatically converted by
* {@code Locale} to the modern and recommended form of "ja-JP-u-ca-japanese".
* Thus, there is no difference in behavior between this method and
* {@code Calendar#getInstance(Locale)}.
*
* @param locale the locale to use to obtain the calendar system, not null
* @return the calendar system associated with the locale, not null
* @throws DateTimeException if the locale-specified calendar cannot be found
*/
static Chronology ofLocale(Locale locale) {
return AbstractChronology.ofLocale(locale);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code Chronology} from a chronology ID or
* calendar system type.
* <p>
* This returns a chronology based on either the ID or the type.
* The {@link #getId() chronology ID} uniquely identifies the chronology.
* The {@link #getCalendarType() calendar system type} is defined by the
* CLDR specification.
* <p>
* The chronology may be a system chronology or a chronology
* provided by the application via ServiceLoader configuration.
* <p>
* Since some calendars can be customized, the ID or type typically refers
* to the default customization. For example, the Gregorian calendar can have multiple
* cutover dates from the Julian, but the lookup only provides the default cutover date.
*
* @param id the chronology ID or calendar system type, not null
* @return the chronology with the identifier requested, not null
* @throws DateTimeException if the chronology cannot be found
*/
static Chronology of(String id) {
return AbstractChronology.of(id);
}
/**
* Returns the available chronologies.
* <p>
* Each returned {@code Chronology} is available for use in the system.
* The set of chronologies includes the system chronologies and
* any chronologies provided by the application via ServiceLoader
* configuration.
*
* @return the independent, modifiable set of the available chronology IDs, not null
*/
static Set<Chronology> getAvailableChronologies() {
return AbstractChronology.getAvailableChronologies();
}
//-----------------------------------------------------------------------
/**
* Gets the ID of the chronology.
* <p>
* The ID uniquely identifies the {@code Chronology}.
* It can be used to lookup the {@code Chronology} using {@link #of(String)}.
*
* @return the chronology ID, not null
* @see #getCalendarType()
*/
String getId();
/**
* Gets the calendar type of the calendar system.
* <p>
* The calendar type is an identifier defined by the CLDR and
* <em>Unicode Locale Data Markup Language (LDML)</em> specifications
* to uniquely identification a calendar.
* The {@code getCalendarType} is the concatenation of the CLDR calendar type
* and the variant, if applicable, is appended separated by "-".
* The calendar type is used to lookup the {@code Chronology} using {@link #of(String)}.
*
* @return the calendar system type, null if the calendar is not defined by CLDR/LDML
* @see #getId()
*/
String getCalendarType();
//-----------------------------------------------------------------------
/**
* Obtains a local date in this chronology from the era, year-of-era,
* month-of-year and day-of-month fields.
*
* @implSpec
* The default implementation combines the era and year-of-era into a proleptic
* year before calling {@link #date(int, int, int)}.
*
* @param era the era of the correct type for the chronology, not null
* @param yearOfEra the chronology year-of-era
* @param month the chronology month-of-year
* @param dayOfMonth the chronology day-of-month
* @return the local date in this chronology, not null
* @throws DateTimeException if unable to create the date
* @throws ClassCastException if the {@code era} is not of the correct type for the chronology
*/
default ChronoLocalDate date(Era era, int yearOfEra, int month, int dayOfMonth) {
return date(prolepticYear(era, yearOfEra), month, dayOfMonth);
}
/**
* Obtains a local date in this chronology from the proleptic-year,
* month-of-year and day-of-month fields.
*
* @param prolepticYear the chronology proleptic-year
* @param month the chronology month-of-year
* @param dayOfMonth the chronology day-of-month
* @return the local date in this chronology, not null
* @throws DateTimeException if unable to create the date
*/
ChronoLocalDate date(int prolepticYear, int month, int dayOfMonth);
/**
* Obtains a local date in this chronology from the era, year-of-era and
* day-of-year fields.
*
* @implSpec
* The default implementation combines the era and year-of-era into a proleptic
* year before calling {@link #dateYearDay(int, int)}.
*
* @param era the era of the correct type for the chronology, not null
* @param yearOfEra the chronology year-of-era
* @param dayOfYear the chronology day-of-year
* @return the local date in this chronology, not null
* @throws DateTimeException if unable to create the date
* @throws ClassCastException if the {@code era} is not of the correct type for the chronology
*/
default ChronoLocalDate dateYearDay(Era era, int yearOfEra, int dayOfYear) {
return dateYearDay(prolepticYear(era, yearOfEra), dayOfYear);
}
/**
* Obtains a local date in this chronology from the proleptic-year and
* day-of-year fields.
*
* @param prolepticYear the chronology proleptic-year
* @param dayOfYear the chronology day-of-year
* @return the local date in this chronology, not null
* @throws DateTimeException if unable to create the date
*/
ChronoLocalDate dateYearDay(int prolepticYear, int dayOfYear);
/**
* Obtains a local date in this chronology from the epoch-day.
* <p>
* The definition of {@link ChronoField#EPOCH_DAY EPOCH_DAY} is the same
* for all calendar systems, thus it can be used for conversion.
*
* @param epochDay the epoch day
* @return the local date in this chronology, not null
* @throws DateTimeException if unable to create the date
*/
ChronoLocalDate dateEpochDay(long epochDay);
//-----------------------------------------------------------------------
/**
* Obtains the current local date in this chronology from the system clock in the default time-zone.
* <p>
* This will query the {@link Clock#systemDefaultZone() system clock} in the default
* time-zone to obtain the current date.
* <p>
* Using this method will prevent the ability to use an alternate clock for testing
* because the clock is hard-coded.
*
* @implSpec
* The default implementation invokes {@link #dateNow(Clock)}.
*
* @return the current local date using the system clock and default time-zone, not null
* @throws DateTimeException if unable to create the date
*/
default ChronoLocalDate dateNow() {
return dateNow(Clock.systemDefaultZone());
}
/**
* Obtains the current local date in this chronology from the system clock in the specified time-zone.
* <p>
* This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date.
* Specifying the time-zone avoids dependence on the default time-zone.
* <p>
* Using this method will prevent the ability to use an alternate clock for testing
* because the clock is hard-coded.
*
* @implSpec
* The default implementation invokes {@link #dateNow(Clock)}.
*
* @param zone the zone ID to use, not null
* @return the current local date using the system clock, not null
* @throws DateTimeException if unable to create the date
*/
default ChronoLocalDate dateNow(ZoneId zone) {
return dateNow(Clock.system(zone));
}
/**
* Obtains the current local date in this chronology from the specified clock.
* <p>
* This will query the specified clock to obtain the current date - today.
* Using this method allows the use of an alternate clock for testing.
* The alternate clock may be introduced using {@link Clock dependency injection}.
*
* @implSpec
* The default implementation invokes {@link #date(TemporalAccessor)} )}.
*
* @param clock the clock to use, not null
* @return the current local date, not null
* @throws DateTimeException if unable to create the date
*/
default ChronoLocalDate dateNow(Clock clock) {
Objects.requireNonNull(clock, "clock");
return date(LocalDate.now(clock));
}
//-----------------------------------------------------------------------
/**
* Obtains a local date in this chronology from another temporal object.
* <p>
* This obtains a date in this chronology based on the specified temporal.
* A {@code TemporalAccessor} represents an arbitrary set of date and time information,
* which this factory converts to an instance of {@code ChronoLocalDate}.
* <p>
* The conversion typically uses the {@link ChronoField#EPOCH_DAY EPOCH_DAY}
* field, which is standardized across calendar systems.
* <p>
* This method matches the signature of the functional interface {@link TemporalQuery}
* allowing it to be used as a query via method reference, {@code aChronology::date}.
*
* @param temporal the temporal object to convert, not null
* @return the local date in this chronology, not null
* @throws DateTimeException if unable to create the date
* @see ChronoLocalDate#from(TemporalAccessor)
*/
ChronoLocalDate date(TemporalAccessor temporal);
/**
* Obtains a local date-time in this chronology from another temporal object.
* <p>
* This obtains a date-time in this chronology based on the specified temporal.
* A {@code TemporalAccessor} represents an arbitrary set of date and time information,
* which this factory converts to an instance of {@code ChronoLocalDateTime}.
* <p>
* The conversion extracts and combines the {@code ChronoLocalDate} and the
* {@code LocalTime} from the temporal object.
* Implementations are permitted to perform optimizations such as accessing
* those fields that are equivalent to the relevant objects.
* The result uses this chronology.
* <p>
* This method matches the signature of the functional interface {@link TemporalQuery}
* allowing it to be used as a query via method reference, {@code aChronology::localDateTime}.
*
* @param temporal the temporal object to convert, not null
* @return the local date-time in this chronology, not null
* @throws DateTimeException if unable to create the date-time
* @see ChronoLocalDateTime#from(TemporalAccessor)
*/
default ChronoLocalDateTime<? extends ChronoLocalDate> localDateTime(TemporalAccessor temporal) {
try {
return date(temporal).atTime(LocalTime.from(temporal));
} catch (DateTimeException ex) {
throw new DateTimeException("Unable to obtain ChronoLocalDateTime from TemporalAccessor: " + temporal.getClass(), ex);
}
}
/**
* Obtains a {@code ChronoZonedDateTime} in this chronology from another temporal object.
* <p>
* This obtains a zoned date-time in this chronology based on the specified temporal.
* A {@code TemporalAccessor} represents an arbitrary set of date and time information,
* which this factory converts to an instance of {@code ChronoZonedDateTime}.
* <p>
* The conversion will first obtain a {@code ZoneId} from the temporal object,
* falling back to a {@code ZoneOffset} if necessary. It will then try to obtain
* an {@code Instant}, falling back to a {@code ChronoLocalDateTime} if necessary.
* The result will be either the combination of {@code ZoneId} or {@code ZoneOffset}
* with {@code Instant} or {@code ChronoLocalDateTime}.
* Implementations are permitted to perform optimizations such as accessing
* those fields that are equivalent to the relevant objects.
* The result uses this chronology.
* <p>
* This method matches the signature of the functional interface {@link TemporalQuery}
* allowing it to be used as a query via method reference, {@code aChronology::zonedDateTime}.
*
* @param temporal the temporal object to convert, not null
* @return the zoned date-time in this chronology, not null
* @throws DateTimeException if unable to create the date-time
* @see ChronoZonedDateTime#from(TemporalAccessor)
*/
default ChronoZonedDateTime<? extends ChronoLocalDate> zonedDateTime(TemporalAccessor temporal) {
try {
ZoneId zone = ZoneId.from(temporal);
try {
Instant instant = Instant.from(temporal);
return zonedDateTime(instant, zone);
} catch (DateTimeException ex1) {
ChronoLocalDateTimeImpl<?> cldt = ChronoLocalDateTimeImpl.ensureValid(this, localDateTime(temporal));
return ChronoZonedDateTimeImpl.ofBest(cldt, zone, null);
}
} catch (DateTimeException ex) {
throw new DateTimeException("Unable to obtain ChronoZonedDateTime from TemporalAccessor: " + temporal.getClass(), ex);
}
}
/**
* Obtains a {@code ChronoZonedDateTime} in this chronology from an {@code Instant}.
* <p>
* This obtains a zoned date-time with the same instant as that specified.
*
* @param instant the instant to create the date-time from, not null
* @param zone the time-zone, not null
* @return the zoned date-time, not null
* @throws DateTimeException if the result exceeds the supported range
*/
default ChronoZonedDateTime<? extends ChronoLocalDate> zonedDateTime(Instant instant, ZoneId zone) {
return ChronoZonedDateTimeImpl.ofInstant(this, instant, zone);
}
//-----------------------------------------------------------------------
/**
* Checks if the specified year is a leap year.
* <p>
* A leap-year is a year of a longer length than normal.
* The exact meaning is determined by the chronology according to the following constraints.
* <ul>
* <li>a leap-year must imply a year-length longer than a non leap-year.
* <li>a chronology that does not support the concept of a year must return false.
* </ul>
*
* @param prolepticYear the proleptic-year to check, not validated for range
* @return true if the year is a leap year
*/
boolean isLeapYear(long prolepticYear);
/**
* Calculates the proleptic-year given the era and year-of-era.
* <p>
* This combines the era and year-of-era into the single proleptic-year field.
* <p>
* If the chronology makes active use of eras, such as {@code JapaneseChronology}
* then the year-of-era will be validated against the era.
* For other chronologies, validation is optional.
*
* @param era the era of the correct type for the chronology, not null
* @param yearOfEra the chronology year-of-era
* @return the proleptic-year
* @throws DateTimeException if unable to convert to a proleptic-year,
* such as if the year is invalid for the era
* @throws ClassCastException if the {@code era} is not of the correct type for the chronology
*/
int prolepticYear(Era era, int yearOfEra);
/**
* Creates the chronology era object from the numeric value.
* <p>
* The era is, conceptually, the largest division of the time-line.
* Most calendar systems have a single epoch dividing the time-line into two eras.
* However, some have multiple eras, such as one for the reign of each leader.
* The exact meaning is determined by the chronology according to the following constraints.
* <p>
* The era in use at 1970-01-01 must have the value 1.
* Later eras must have sequentially higher values.
* Earlier eras must have sequentially lower values.
* Each chronology must refer to an enum or similar singleton to provide the era values.
* <p>
* This method returns the singleton era of the correct type for the specified era value.
*
* @param eraValue the era value
* @return the calendar system era, not null
* @throws DateTimeException if unable to create the era
*/
Era eraOf(int eraValue);
/**
* Gets the list of eras for the chronology.
* <p>
* Most calendar systems have an era, within which the year has meaning.
* If the calendar system does not support the concept of eras, an empty
* list must be returned.
*
* @return the list of eras for the chronology, may be immutable, not null
*/
List<Era> eras();
//-----------------------------------------------------------------------
/**
* Gets the range of valid values for the specified field.
* <p>
* All fields can be expressed as a {@code long} integer.
* This method returns an object that describes the valid range for that value.
* <p>
* Note that the result only describes the minimum and maximum valid values
* and it is important not to read too much into them. For example, there
* could be values within the range that are invalid for the field.
* <p>
* This method will return a result whether or not the chronology supports the field.
*
* @param field the field to get the range for, not null
* @return the range of valid values for the field, not null
* @throws DateTimeException if the range for the field cannot be obtained
*/
ValueRange range(ChronoField field);
//-----------------------------------------------------------------------
/**
* Gets the textual representation of this chronology.
* <p>
* This returns the textual name used to identify the chronology,
* suitable for presentation to the user.
* The parameters control the style of the returned text and the locale.
*
* @implSpec
* The default implementation behaves as the the formatter was used to
* format the chronology textual name.
*
* @param style the style of the text required, not null
* @param locale the locale to use, not null
* @return the text value of the chronology, not null
*/
default String getDisplayName(TextStyle style, Locale locale) {
TemporalAccessor temporal = new TemporalAccessor() {
@Override
public boolean isSupported(TemporalField field) {
return false;
}
@Override
public long getLong(TemporalField field) {
throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
}
@SuppressWarnings("unchecked")
@Override
public <R> R query(TemporalQuery<R> query) {
if (query == TemporalQueries.chronology()) {
return (R) Chronology.this;
}
return TemporalAccessor.super.query(query);
}
};
return new DateTimeFormatterBuilder().appendChronologyText(style).toFormatter(locale).format(temporal);
}
//-----------------------------------------------------------------------
/**
* Resolves parsed {@code ChronoField} values into a date during parsing.
* <p>
* Most {@code TemporalField} implementations are resolved using the
* resolve method on the field. By contrast, the {@code ChronoField} class
* defines fields that only have meaning relative to the chronology.
* As such, {@code ChronoField} date fields are resolved here in the
* context of a specific chronology.
* <p>
* The default implementation, which explains typical resolve behaviour,
* is provided in {@link AbstractChronology}.
*
* @param fieldValues the map of fields to values, which can be updated, not null
* @param resolverStyle the requested type of resolve, not null
* @return the resolved date, null if insufficient information to create a date
* @throws DateTimeException if the date cannot be resolved, typically
* because of a conflict in the input data
*/
ChronoLocalDate resolveDate(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle);
//-----------------------------------------------------------------------
/**
* Obtains a period for this chronology based on years, months and days.
* <p>
* This returns a period tied to this chronology using the specified
* years, months and days. All supplied chronologies use periods
* based on years, months and days, however the {@code ChronoPeriod} API
* allows the period to be represented using other units.
*
* @implSpec
* The default implementation returns an implementation class suitable
* for most calendar systems. It is based solely on the three units.
* Normalization, addition and subtraction derive the number of months
* in a year from the {@link #range(ChronoField)}. If the number of
* months within a year is fixed, then the calculation approach for
* addition, subtraction and normalization is slightly different.
* <p>
* If implementing an unusual calendar system that is not based on
* years, months and days, or where you want direct control, then
* the {@code ChronoPeriod} interface must be directly implemented.
* <p>
* The returned period is immutable and thread-safe.
*
* @param years the number of years, may be negative
* @param months the number of years, may be negative
* @param days the number of years, may be negative
* @return the period in terms of this chronology, not null
*/
default ChronoPeriod period(int years, int months, int days) {
return new ChronoPeriodImpl(this, years, months, days);
}
//-----------------------------------------------------------------------
/**
* Compares this chronology to another chronology.
* <p>
* The comparison order first by the chronology ID string, then by any
* additional information specific to the subclass.
* It is "consistent with equals", as defined by {@link Comparable}.
*
* @param other the other chronology to compare to, not null
* @return the comparator value, negative if less, positive if greater
*/
@Override
int compareTo(Chronology other);
/**
* Checks if this chronology is equal to another chronology.
* <p>
* The comparison is based on the entire state of the object.
*
* @param obj the object to check, null returns false
* @return true if this is equal to the other chronology
*/
@Override
boolean equals(Object obj);
/**
* A hash code for this chronology.
* <p>
* The hash code should be based on the entire state of the object.
*
* @return a suitable hash code
*/
@Override
int hashCode();
//-----------------------------------------------------------------------
/**
* Outputs this chronology as a {@code String}.
* <p>
* The format should include the entire state of the object.
*
* @return a string representation of this chronology, not null
*/
@Override
String toString();
}