1 /*
2 * Copyright (c) 2012, 2019, 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 static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH;
60 import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR;
61 import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_MONTH;
62 import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_YEAR;
63 import static java.time.temporal.ChronoField.DAY_OF_MONTH;
64 import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
65 import static java.time.temporal.ChronoField.YEAR;
66
67 import java.io.IOException;
68 import java.io.InvalidObjectException;
69 import java.io.ObjectInput;
70 import java.io.ObjectInputStream;
71 import java.io.ObjectOutput;
72 import java.io.Serializable;
73 import java.time.Clock;
74 import java.time.DateTimeException;
75 import java.time.LocalDate;
76 import java.time.LocalTime;
77 import java.time.ZoneId;
78 import java.time.temporal.ChronoField;
79 import java.time.temporal.TemporalAccessor;
80 import java.time.temporal.TemporalAdjuster;
81 import java.time.temporal.TemporalAmount;
82 import java.time.temporal.TemporalField;
83 import java.time.temporal.TemporalQuery;
84 import java.time.temporal.TemporalUnit;
85 import java.time.temporal.UnsupportedTemporalTypeException;
86 import java.time.temporal.ValueRange;
87
88 /**
89 * A date in the Hijrah calendar system.
90 * <p>
91 * This date operates using one of several variants of the
92 * {@linkplain HijrahChronology Hijrah calendar}.
93 * <p>
94 * The Hijrah calendar has a different total of days in a year than
95 * Gregorian calendar, and the length of each month is based on the period
96 * of a complete revolution of the moon around the earth
97 * (as between successive new moons).
98 * Refer to the {@link HijrahChronology} for details of supported variants.
99 * <p>
100 * Each HijrahDate is created bound to a particular HijrahChronology,
101 * The same chronology is propagated to each HijrahDate computed from the date.
102 * To use a different Hijrah variant, its HijrahChronology can be used
103 * to create new HijrahDate instances.
104 * Alternatively, the {@link #withVariant} method can be used to convert
105 * to a new HijrahChronology.
106 * <p>
107 * This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
108 * class; programmers should treat instances that are
109 * {@linkplain #equals(Object) equal} as interchangeable and should not
110 * use instances for synchronization, or unpredictable behavior may
111 * occur. For example, in a future release, synchronization may fail.
112 * The {@code equals} method should be used for comparisons.
113 *
114 * @implSpec
115 * This class is immutable and thread-safe.
116 *
117 * @since 1.8
118 */
119 @jdk.internal.ValueBased
120 @jdk.internal.MigratedValueClass
121 public final class HijrahDate
122 extends ChronoLocalDateImpl<HijrahDate>
123 implements ChronoLocalDate, Serializable {
124
125 /**
126 * Serialization version.
127 */
128 @java.io.Serial
129 private static final long serialVersionUID = -5207853542612002020L;
130 /**
131 * The Chronology of this HijrahDate.
132 */
133 private final transient HijrahChronology chrono;
134 /**
135 * The proleptic year.
136 */
137 private final transient int prolepticYear;
138 /**
139 * The month-of-year.
140 */
141 private final transient int monthOfYear;
142 /**
143 * The day-of-month.
144 */
145 private final transient int dayOfMonth;
146
147 //-------------------------------------------------------------------------
148 /**
149 * Obtains an instance of {@code HijrahDate} from the Hijrah proleptic year,
150 * month-of-year and day-of-month.
151 *
152 * @param prolepticYear the proleptic year to represent in the Hijrah calendar
153 * @param monthOfYear the month-of-year to represent, from 1 to 12
154 * @param dayOfMonth the day-of-month to represent, from 1 to 30
155 * @return the Hijrah date, never null
156 * @throws DateTimeException if the value of any field is out of range
157 */
158 static HijrahDate of(HijrahChronology chrono, int prolepticYear, int monthOfYear, int dayOfMonth) {
159 return new HijrahDate(chrono, prolepticYear, monthOfYear, dayOfMonth);
160 }
161
162 /**
163 * Returns a HijrahDate for the chronology and epochDay.
164 * @param chrono The Hijrah chronology
165 * @param epochDay the epoch day
166 * @return a HijrahDate for the epoch day; non-null
167 */
168 static HijrahDate ofEpochDay(HijrahChronology chrono, long epochDay) {
169 return new HijrahDate(chrono, epochDay);
170 }
171
172 //-----------------------------------------------------------------------
173 /**
174 * Obtains the current {@code HijrahDate} of the Islamic Umm Al-Qura calendar
175 * in the default time-zone.
176 * <p>
177 * This will query the {@link Clock#systemDefaultZone() system clock} in the default
178 * time-zone to obtain the current date.
179 * <p>
180 * Using this method will prevent the ability to use an alternate clock for testing
181 * because the clock is hard-coded.
182 *
183 * @return the current date using the system clock and default time-zone, not null
184 */
185 public static HijrahDate now() {
186 return now(Clock.systemDefaultZone());
187 }
188
189 /**
190 * Obtains the current {@code HijrahDate} of the Islamic Umm Al-Qura calendar
191 * in the specified time-zone.
192 * <p>
193 * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date.
194 * Specifying the time-zone avoids dependence on the default time-zone.
195 * <p>
196 * Using this method will prevent the ability to use an alternate clock for testing
197 * because the clock is hard-coded.
198 *
199 * @param zone the zone ID to use, not null
200 * @return the current date using the system clock, not null
201 */
202 public static HijrahDate now(ZoneId zone) {
203 return now(Clock.system(zone));
204 }
205
206 /**
207 * Obtains the current {@code HijrahDate} of the Islamic Umm Al-Qura calendar
208 * from the specified clock.
209 * <p>
210 * This will query the specified clock to obtain the current date - today.
211 * Using this method allows the use of an alternate clock for testing.
212 * The alternate clock may be introduced using {@linkplain Clock dependency injection}.
213 *
214 * @param clock the clock to use, not null
215 * @return the current date, not null
216 * @throws DateTimeException if the current date cannot be obtained
217 */
218 public static HijrahDate now(Clock clock) {
219 return HijrahDate.ofEpochDay(HijrahChronology.INSTANCE, LocalDate.now(clock).toEpochDay());
220 }
221
222 /**
223 * Obtains a {@code HijrahDate} of the Islamic Umm Al-Qura calendar
224 * from the proleptic-year, month-of-year and day-of-month fields.
225 * <p>
226 * This returns a {@code HijrahDate} with the specified fields.
227 * The day must be valid for the year and month, otherwise an exception will be thrown.
228 *
229 * @param prolepticYear the Hijrah proleptic-year
230 * @param month the Hijrah month-of-year, from 1 to 12
231 * @param dayOfMonth the Hijrah day-of-month, from 1 to 30
232 * @return the date in Hijrah calendar system, not null
233 * @throws DateTimeException if the value of any field is out of range,
234 * or if the day-of-month is invalid for the month-year
235 */
236 public static HijrahDate of(int prolepticYear, int month, int dayOfMonth) {
237 return HijrahChronology.INSTANCE.date(prolepticYear, month, dayOfMonth);
238 }
239
240 /**
241 * Obtains a {@code HijrahDate} of the Islamic Umm Al-Qura calendar from a temporal object.
242 * <p>
243 * This obtains a date in the Hijrah calendar system based on the specified temporal.
244 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
245 * which this factory converts to an instance of {@code HijrahDate}.
246 * <p>
247 * The conversion typically uses the {@link ChronoField#EPOCH_DAY EPOCH_DAY}
248 * field, which is standardized across calendar systems.
249 * <p>
250 * This method matches the signature of the functional interface {@link TemporalQuery}
251 * allowing it to be used as a query via method reference, {@code HijrahDate::from}.
252 *
253 * @param temporal the temporal object to convert, not null
254 * @return the date in Hijrah calendar system, not null
255 * @throws DateTimeException if unable to convert to a {@code HijrahDate}
256 */
257 public static HijrahDate from(TemporalAccessor temporal) {
258 return HijrahChronology.INSTANCE.date(temporal);
259 }
260
261 //-----------------------------------------------------------------------
262 /**
263 * Constructs an {@code HijrahDate} with the proleptic-year, month-of-year and
264 * day-of-month fields.
265 *
266 * @param chrono The chronology to create the date with
267 * @param prolepticYear the proleptic year
268 * @param monthOfYear the month of year
269 * @param dayOfMonth the day of month
270 */
271 private HijrahDate(HijrahChronology chrono, int prolepticYear, int monthOfYear, int dayOfMonth) {
272 // Computing the Gregorian day checks the valid ranges
273 chrono.getEpochDay(prolepticYear, monthOfYear, dayOfMonth);
274
275 this.chrono = chrono;
276 this.prolepticYear = prolepticYear;
277 this.monthOfYear = monthOfYear;
278 this.dayOfMonth = dayOfMonth;
279 }
280
281 /**
282 * Constructs an instance with the Epoch Day.
283 *
284 * @param epochDay the epochDay
285 */
286 private HijrahDate(HijrahChronology chrono, long epochDay) {
287 int[] dateInfo = chrono.getHijrahDateInfo((int)epochDay);
288
289 this.chrono = chrono;
290 this.prolepticYear = dateInfo[0];
291 this.monthOfYear = dateInfo[1];
292 this.dayOfMonth = dateInfo[2];
293 }
294
295 //-----------------------------------------------------------------------
296 /**
297 * Gets the chronology of this date, which is the Hijrah calendar system.
298 * <p>
299 * The {@code Chronology} represents the calendar system in use.
300 * The era and other fields in {@link ChronoField} are defined by the chronology.
301 *
302 * @return the Hijrah chronology, not null
303 */
304 @Override
305 public HijrahChronology getChronology() {
306 return chrono;
307 }
308
309 /**
310 * Gets the era applicable at this date.
311 * <p>
312 * The Hijrah calendar system has one era, 'AH',
313 * defined by {@link HijrahEra}.
314 *
315 * @return the era applicable at this date, not null
316 */
317 @Override
318 public HijrahEra getEra() {
319 return HijrahEra.AH;
320 }
321
322 /**
323 * Returns the length of the month represented by this date.
324 * <p>
325 * This returns the length of the month in days.
326 * Month lengths in the Hijrah calendar system vary between 29 and 30 days.
327 *
328 * @return the length of the month in days
329 */
330 @Override
331 public int lengthOfMonth() {
332 return chrono.getMonthLength(prolepticYear, monthOfYear);
333 }
334
335 /**
336 * Returns the length of the year represented by this date.
337 * <p>
338 * This returns the length of the year in days.
339 * A Hijrah calendar system year is typically shorter than
340 * that of the ISO calendar system.
341 *
342 * @return the length of the year in days
343 */
344 @Override
345 public int lengthOfYear() {
346 return chrono.getYearLength(prolepticYear);
347 }
348
349 //-----------------------------------------------------------------------
350 @Override
351 public ValueRange range(TemporalField field) {
352 if (field instanceof ChronoField) {
353 if (isSupported(field)) {
354 ChronoField f = (ChronoField) field;
355 return switch (f) {
356 case DAY_OF_MONTH -> ValueRange.of(1, lengthOfMonth());
357 case DAY_OF_YEAR -> ValueRange.of(1, lengthOfYear());
358 case ALIGNED_WEEK_OF_MONTH -> ValueRange.of(1, 5); // TODO
359 // TODO does the limited range of valid years cause years to
360 // start/end part way through? that would affect range
361 default -> getChronology().range(f);
362 };
363 }
364 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
365 }
366 return field.rangeRefinedBy(this);
367 }
368
369 @Override
370 public long getLong(TemporalField field) {
371 if (field instanceof ChronoField) {
372 return switch ((ChronoField) field) {
373 case DAY_OF_WEEK -> getDayOfWeek();
374 case ALIGNED_DAY_OF_WEEK_IN_MONTH -> ((dayOfMonth - 1) % 7) + 1;
375 case ALIGNED_DAY_OF_WEEK_IN_YEAR -> ((getDayOfYear() - 1) % 7) + 1;
376 case DAY_OF_MONTH -> this.dayOfMonth;
377 case DAY_OF_YEAR -> this.getDayOfYear();
378 case EPOCH_DAY -> toEpochDay();
379 case ALIGNED_WEEK_OF_MONTH -> ((dayOfMonth - 1) / 7) + 1;
380 case ALIGNED_WEEK_OF_YEAR -> ((getDayOfYear() - 1) / 7) + 1;
381 case MONTH_OF_YEAR -> monthOfYear;
382 case PROLEPTIC_MONTH -> getProlepticMonth();
383 case YEAR_OF_ERA -> prolepticYear;
384 case YEAR -> prolepticYear;
385 case ERA -> getEraValue();
386 default -> throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
387 };
388 }
389 return field.getFrom(this);
390 }
391
392 private long getProlepticMonth() {
393 return prolepticYear * 12L + monthOfYear - 1;
394 }
395
396 @Override
397 public HijrahDate with(TemporalField field, long newValue) {
398 if (field instanceof ChronoField chronoField) {
399 // not using checkValidIntValue so EPOCH_DAY and PROLEPTIC_MONTH work
400 chrono.range(chronoField).checkValidValue(newValue, chronoField); // TODO: validate value
401 int nvalue = (int) newValue;
402 return switch (chronoField) {
403 case DAY_OF_WEEK -> plusDays(newValue - getDayOfWeek());
404 case ALIGNED_DAY_OF_WEEK_IN_MONTH -> plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_MONTH));
405 case ALIGNED_DAY_OF_WEEK_IN_YEAR -> plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_YEAR));
406 case DAY_OF_MONTH -> resolvePreviousValid(prolepticYear, monthOfYear, nvalue);
407 case DAY_OF_YEAR -> plusDays(Math.min(nvalue, lengthOfYear()) - getDayOfYear());
408 case EPOCH_DAY -> new HijrahDate(chrono, newValue);
409 case ALIGNED_WEEK_OF_MONTH -> plusDays((newValue - getLong(ALIGNED_WEEK_OF_MONTH)) * 7);
410 case ALIGNED_WEEK_OF_YEAR -> plusDays((newValue - getLong(ALIGNED_WEEK_OF_YEAR)) * 7);
411 case MONTH_OF_YEAR -> resolvePreviousValid(prolepticYear, nvalue, dayOfMonth);
412 case PROLEPTIC_MONTH -> plusMonths(newValue - getProlepticMonth());
413 case YEAR_OF_ERA -> resolvePreviousValid(prolepticYear >= 1 ? nvalue : 1 - nvalue, monthOfYear, dayOfMonth);
414 case YEAR -> resolvePreviousValid(nvalue, monthOfYear, dayOfMonth);
415 case ERA -> resolvePreviousValid(1 - prolepticYear, monthOfYear, dayOfMonth);
416 default -> throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
417 };
418 }
419 return super.with(field, newValue);
420 }
421
422 private HijrahDate resolvePreviousValid(int prolepticYear, int month, int day) {
423 int monthDays = chrono.getMonthLength(prolepticYear, month);
424 if (day > monthDays) {
425 day = monthDays;
426 }
427 return HijrahDate.of(chrono, prolepticYear, month, day);
428 }
429
430 /**
431 * {@inheritDoc}
432 * @throws DateTimeException if unable to make the adjustment.
433 * For example, if the adjuster requires an ISO chronology
434 * @throws ArithmeticException {@inheritDoc}
435 */
436 @Override
437 public HijrahDate with(TemporalAdjuster adjuster) {
438 return super.with(adjuster);
439 }
440
441 /**
442 * Returns a {@code HijrahDate} with the Chronology requested.
443 * <p>
444 * The year, month, and day are checked against the new requested
445 * HijrahChronology. If the chronology has a shorter month length
446 * for the month, the day is reduced to be the last day of the month.
447 *
448 * @param chronology the new HijrahChonology, non-null
449 * @return a HijrahDate with the requested HijrahChronology, non-null
450 */
451 public HijrahDate withVariant(HijrahChronology chronology) {
452 if (chrono == chronology) {
453 return this;
454 }
455 // Like resolvePreviousValid the day is constrained to stay in the same month
456 int monthDays = chronology.getDayOfYear(prolepticYear, monthOfYear);
457 return HijrahDate.of(chronology, prolepticYear, monthOfYear,(dayOfMonth > monthDays) ? monthDays : dayOfMonth );
458 }
459
460 /**
461 * {@inheritDoc}
462 * @throws DateTimeException {@inheritDoc}
463 * @throws ArithmeticException {@inheritDoc}
464 */
465 @Override
466 public HijrahDate plus(TemporalAmount amount) {
467 return super.plus(amount);
468 }
469
470 /**
471 * {@inheritDoc}
472 * @throws DateTimeException {@inheritDoc}
473 * @throws ArithmeticException {@inheritDoc}
474 */
475 @Override
476 public HijrahDate minus(TemporalAmount amount) {
477 return super.minus(amount);
478 }
479
480 @Override
481 public long toEpochDay() {
482 return chrono.getEpochDay(prolepticYear, monthOfYear, dayOfMonth);
483 }
484
485 /**
486 * Gets the day-of-year field.
487 * <p>
488 * This method returns the primitive {@code int} value for the day-of-year.
489 *
490 * @return the day-of-year
491 */
492 private int getDayOfYear() {
493 return chrono.getDayOfYear(prolepticYear, monthOfYear) + dayOfMonth;
494 }
495
496 /**
497 * Gets the day-of-week value.
498 *
499 * @return the day-of-week; computed from the epochday
500 */
501 private int getDayOfWeek() {
502 int dow0 = Math.floorMod(toEpochDay() + 3, 7);
503 return dow0 + 1;
504 }
505
506 /**
507 * Gets the Era of this date.
508 *
509 * @return the Era of this date; computed from epochDay
510 */
511 private int getEraValue() {
512 return (prolepticYear > 1 ? 1 : 0);
513 }
514
515 //-----------------------------------------------------------------------
516 /**
517 * Checks if the year is a leap year, according to the Hijrah calendar system rules.
518 *
519 * @return true if this date is in a leap year
520 */
521 @Override
522 public boolean isLeapYear() {
523 return chrono.isLeapYear(prolepticYear);
524 }
525
526 //-----------------------------------------------------------------------
527 @Override
528 HijrahDate plusYears(long years) {
529 if (years == 0) {
530 return this;
531 }
532 int newYear = Math.addExact(this.prolepticYear, (int)years);
533 return resolvePreviousValid(newYear, monthOfYear, dayOfMonth);
534 }
535
536 @Override
537 HijrahDate plusMonths(long monthsToAdd) {
538 if (monthsToAdd == 0) {
539 return this;
540 }
541 long monthCount = prolepticYear * 12L + (monthOfYear - 1);
542 long calcMonths = monthCount + monthsToAdd; // safe overflow
543 int newYear = chrono.checkValidYear(Math.floorDiv(calcMonths, 12L));
544 int newMonth = (int)Math.floorMod(calcMonths, 12L) + 1;
545 return resolvePreviousValid(newYear, newMonth, dayOfMonth);
546 }
547
548 @Override
549 HijrahDate plusWeeks(long weeksToAdd) {
550 return super.plusWeeks(weeksToAdd);
551 }
552
553 @Override
554 HijrahDate plusDays(long days) {
555 return new HijrahDate(chrono, toEpochDay() + days);
556 }
557
558 @Override
559 public HijrahDate plus(long amountToAdd, TemporalUnit unit) {
560 return super.plus(amountToAdd, unit);
561 }
562
563 @Override
564 public HijrahDate minus(long amountToSubtract, TemporalUnit unit) {
565 return super.minus(amountToSubtract, unit);
566 }
567
568 @Override
569 HijrahDate minusYears(long yearsToSubtract) {
570 return super.minusYears(yearsToSubtract);
571 }
572
573 @Override
574 HijrahDate minusMonths(long monthsToSubtract) {
575 return super.minusMonths(monthsToSubtract);
576 }
577
578 @Override
579 HijrahDate minusWeeks(long weeksToSubtract) {
580 return super.minusWeeks(weeksToSubtract);
581 }
582
583 @Override
584 HijrahDate minusDays(long daysToSubtract) {
585 return super.minusDays(daysToSubtract);
586 }
587
588 @Override // for javadoc and covariant return type
589 @SuppressWarnings("unchecked")
590 public final ChronoLocalDateTime<HijrahDate> atTime(LocalTime localTime) {
591 return (ChronoLocalDateTime<HijrahDate>)super.atTime(localTime);
592 }
593
594 @Override
595 public ChronoPeriod until(ChronoLocalDate endDate) {
596 // TODO: untested
597 HijrahDate end = getChronology().date(endDate);
598 long totalMonths = (end.prolepticYear - this.prolepticYear) * 12 + (end.monthOfYear - this.monthOfYear); // safe
599 int days = end.dayOfMonth - this.dayOfMonth;
600 if (totalMonths > 0 && days < 0) {
601 totalMonths--;
602 HijrahDate calcDate = this.plusMonths(totalMonths);
603 days = (int) (end.toEpochDay() - calcDate.toEpochDay()); // safe
604 } else if (totalMonths < 0 && days > 0) {
605 totalMonths++;
606 days -= end.lengthOfMonth();
607 }
608 long years = totalMonths / 12; // safe
609 int months = (int) (totalMonths % 12); // safe
610 return getChronology().period(Math.toIntExact(years), months, days);
611 }
612
613 //-------------------------------------------------------------------------
614 /**
615 * Compares this date to another date, including the chronology.
616 * <p>
617 * Compares this {@code HijrahDate} with another ensuring that the date is the same.
618 * <p>
619 * Only objects of type {@code HijrahDate} are compared, other types return false.
620 * To compare the dates of two {@code TemporalAccessor} instances, including dates
621 * in two different chronologies, use {@link ChronoField#EPOCH_DAY} as a comparator.
622 *
623 * @param obj the object to check, null returns false
624 * @return true if this is equal to the other date and the Chronologies are equal
625 */
626 @Override // override for performance
627 public boolean equals(Object obj) {
628 if (this == obj) {
629 return true;
630 }
631 return (obj instanceof HijrahDate otherDate)
632 && prolepticYear == otherDate.prolepticYear
633 && this.monthOfYear == otherDate.monthOfYear
634 && this.dayOfMonth == otherDate.dayOfMonth
635 && getChronology().equals(otherDate.getChronology());
636 }
637
638 /**
639 * A hash code for this date.
640 *
641 * @return a suitable hash code based only on the Chronology and the date
642 */
643 @Override // override for performance
644 public int hashCode() {
645 int yearValue = prolepticYear;
646 int monthValue = monthOfYear;
647 int dayValue = dayOfMonth;
648 return getChronology().getId().hashCode() ^ (yearValue & 0xFFFFF800)
649 ^ ((yearValue << 11) + (monthValue << 6) + (dayValue));
650 }
651
652 //-----------------------------------------------------------------------
653 /**
654 * Defend against malicious streams.
655 *
656 * @param s the stream to read
657 * @throws InvalidObjectException always
658 */
659 @java.io.Serial
660 private void readObject(ObjectInputStream s) throws InvalidObjectException {
661 throw new InvalidObjectException("Deserialization via serialization delegate");
662 }
663
664 /**
665 * Writes the object using a
666 * <a href="{@docRoot}/serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>.
667 * @serialData
668 * <pre>
669 * out.writeByte(6); // identifies a HijrahDate
670 * out.writeObject(chrono); // the HijrahChronology variant
671 * out.writeInt(get(YEAR));
672 * out.writeByte(get(MONTH_OF_YEAR));
673 * out.writeByte(get(DAY_OF_MONTH));
674 * </pre>
675 *
676 * @return the instance of {@code Ser}, not null
677 */
678 @java.io.Serial
679 private Object writeReplace() {
680 return new Ser(Ser.HIJRAH_DATE_TYPE, this);
681 }
682
683 void writeExternal(ObjectOutput out) throws IOException {
684 // HijrahChronology is implicit in the Hijrah_DATE_TYPE
685 out.writeObject(getChronology());
686 out.writeInt(get(YEAR));
687 out.writeByte(get(MONTH_OF_YEAR));
688 out.writeByte(get(DAY_OF_MONTH));
689 }
690
691 static HijrahDate readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
692 HijrahChronology chrono = (HijrahChronology) in.readObject();
693 int year = in.readInt();
694 int month = in.readByte();
695 int dayOfMonth = in.readByte();
696 return chrono.date(year, month, dayOfMonth);
697 }
698
699 }