1 /*
2 * Copyright (c) 2012, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 /*
27 * This file is available under and governed by the GNU General Public
28 * License version 2 only, as published by the Free Software Foundation.
29 * However, the following notice accompanied the original version of this
30 * file:
31 *
32 * Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
33 *
34 * All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions are met:
38 *
39 * * Redistributions of source code must retain the above copyright notice,
40 * this list of conditions and the following disclaimer.
41 *
42 * * Redistributions in binary form must reproduce the above copyright notice,
43 * this list of conditions and the following disclaimer in the documentation
44 * and/or other materials provided with the distribution.
45 *
46 * * Neither the name of JSR-310 nor the names of its contributors
47 * may be used to endorse or promote products derived from this software
48 * without specific prior written permission.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
51 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
52 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
53 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
54 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
55 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
56 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
57 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
58 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
59 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
60 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61 */
62 package java.time;
63
64 import static java.time.LocalTime.SECONDS_PER_DAY;
65 import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH;
66 import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR;
67 import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_MONTH;
68 import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_YEAR;
69 import static java.time.temporal.ChronoField.DAY_OF_MONTH;
70 import static java.time.temporal.ChronoField.DAY_OF_YEAR;
71 import static java.time.temporal.ChronoField.EPOCH_DAY;
72 import static java.time.temporal.ChronoField.ERA;
73 import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
74 import static java.time.temporal.ChronoField.PROLEPTIC_MONTH;
75 import static java.time.temporal.ChronoField.YEAR;
76
77 import java.io.DataInput;
78 import java.io.DataOutput;
79 import java.io.IOException;
80 import java.io.InvalidObjectException;
81 import java.io.ObjectInputStream;
82 import java.io.Serializable;
83 import java.time.chrono.ChronoLocalDate;
84 import java.time.chrono.IsoEra;
85 import java.time.chrono.IsoChronology;
86 import java.time.format.DateTimeFormatter;
87 import java.time.format.DateTimeParseException;
88 import java.time.temporal.ChronoField;
89 import java.time.temporal.ChronoUnit;
90 import java.time.temporal.Temporal;
91 import java.time.temporal.TemporalAccessor;
92 import java.time.temporal.TemporalAdjuster;
93 import java.time.temporal.TemporalAmount;
94 import java.time.temporal.TemporalField;
95 import java.time.temporal.TemporalQueries;
96 import java.time.temporal.TemporalQuery;
97 import java.time.temporal.TemporalUnit;
98 import java.time.temporal.UnsupportedTemporalTypeException;
99 import java.time.temporal.ValueRange;
100 import java.time.zone.ZoneOffsetTransition;
101 import java.time.zone.ZoneRules;
102 import java.util.Objects;
103 import java.util.stream.LongStream;
104 import java.util.stream.Stream;
105
106 /**
107 * A date without a time-zone in the ISO-8601 calendar system,
108 * such as {@code 2007-12-03}.
109 * <p>
110 * {@code LocalDate} is an immutable date-time object that represents a date,
111 * often viewed as year-month-day. Other date fields, such as day-of-year,
112 * day-of-week and week-of-year, can also be accessed.
113 * For example, the value "2nd October 2007" can be stored in a {@code LocalDate}.
114 * <p>
115 * This class does not store or represent a time or time-zone.
116 * Instead, it is a description of the date, as used for birthdays.
117 * It cannot represent an instant on the time-line without additional information
118 * such as an offset or time-zone.
119 * <p>
120 * The ISO-8601 calendar system is the modern civil calendar system used today
121 * in most of the world. It is equivalent to the proleptic Gregorian calendar
122 * system, in which today's rules for leap years are applied for all time.
123 * For most applications written today, the ISO-8601 rules are entirely suitable.
124 * However, any application that makes use of historical dates, and requires them
125 * to be accurate will find the ISO-8601 approach unsuitable.
126 * <p>
127 * This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
128 * class; programmers should treat instances that are
129 * {@linkplain #equals(Object) equal} as interchangeable and should not
130 * use instances for synchronization, or unpredictable behavior may
131 * occur. For example, in a future release, synchronization may fail.
132 * The {@code equals} method should be used for comparisons.
133 *
134 * @implSpec
135 * This class is immutable and thread-safe.
136 *
137 * @since 1.8
138 */
139 @jdk.internal.ValueBased
140 public final class LocalDate
141 implements Temporal, TemporalAdjuster, ChronoLocalDate, Serializable {
142
143 /**
144 * The minimum supported {@code LocalDate}, '-999999999-01-01'.
145 * This could be used by an application as a "far past" date.
146 */
147 public static final LocalDate MIN = LocalDate.of(Year.MIN_VALUE, 1, 1);
148 /**
149 * The maximum supported {@code LocalDate}, '+999999999-12-31'.
150 * This could be used by an application as a "far future" date.
151 */
152 public static final LocalDate MAX = LocalDate.of(Year.MAX_VALUE, 12, 31);
153 /**
154 * The epoch year {@code LocalDate}, '1970-01-01'.
155 *
156 * @since 9
157 */
158 public static final LocalDate EPOCH = LocalDate.of(1970, 1, 1);
159
160 /**
161 * Serialization version.
162 */
163 @java.io.Serial
164 private static final long serialVersionUID = 2942565459149668126L;
165 /**
166 * The number of days in a 400 year cycle.
167 */
168 private static final int DAYS_PER_CYCLE = 146097;
169 /**
170 * The number of days from year zero to year 1970.
171 * There are five 400 year cycles from year zero to 2000.
172 * There are 7 leap years from 1970 to 2000.
173 */
174 static final long DAYS_0000_TO_1970 = (DAYS_PER_CYCLE * 5L) - (30L * 365L + 7L);
175
176 /**
177 * The year.
178 */
179 private final int year;
180 /**
181 * The month-of-year.
182 */
183 private final short month;
184 /**
185 * The day-of-month.
186 */
187 private final short day;
188
189 //-----------------------------------------------------------------------
190 /**
191 * Obtains the current date from the system clock in the default time-zone.
192 * <p>
193 * This will query the {@link Clock#systemDefaultZone() system clock} in the default
194 * time-zone to obtain the current date.
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 * @return the current date using the system clock and default time-zone, not null
200 */
201 public static LocalDate now() {
202 return now(Clock.systemDefaultZone());
203 }
204
205 /**
206 * Obtains the current date from the system clock in the specified time-zone.
207 * <p>
208 * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date.
209 * Specifying the time-zone avoids dependence on the default time-zone.
210 * <p>
211 * Using this method will prevent the ability to use an alternate clock for testing
212 * because the clock is hard-coded.
213 *
214 * @param zone the zone ID to use, not null
215 * @return the current date using the system clock, not null
216 */
217 public static LocalDate now(ZoneId zone) {
218 return now(Clock.system(zone));
219 }
220
221 /**
222 * Obtains the current date from the specified clock.
223 * <p>
224 * This will query the specified clock to obtain the current date - today.
225 * Using this method allows the use of an alternate clock for testing.
226 * The alternate clock may be introduced using {@link Clock dependency injection}.
227 *
228 * @param clock the clock to use, not null
229 * @return the current date, not null
230 */
231 public static LocalDate now(Clock clock) {
232 Objects.requireNonNull(clock, "clock");
233 final Instant now = clock.instant(); // called once
234 return ofInstant(now, clock.getZone());
235 }
236
237 //-----------------------------------------------------------------------
238 /**
239 * Obtains an instance of {@code LocalDate} from a year, month and day.
240 * <p>
241 * This returns a {@code LocalDate} with the specified year, month and day-of-month.
242 * The day must be valid for the year and month, otherwise an exception will be thrown.
243 *
244 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
245 * @param month the month-of-year to represent, not null
246 * @param dayOfMonth the day-of-month to represent, from 1 to 31
247 * @return the local date, not null
248 * @throws DateTimeException if the value of any field is out of range,
249 * or if the day-of-month is invalid for the month-year
250 */
251 public static LocalDate of(int year, Month month, int dayOfMonth) {
252 YEAR.checkValidValue(year);
253 Objects.requireNonNull(month, "month");
254 DAY_OF_MONTH.checkValidValue(dayOfMonth);
255 return create(year, month.getValue(), dayOfMonth);
256 }
257
258 /**
259 * Obtains an instance of {@code LocalDate} from a year, month and day.
260 * <p>
261 * This returns a {@code LocalDate} with the specified year, month and day-of-month.
262 * The day must be valid for the year and month, otherwise an exception will be thrown.
263 *
264 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
265 * @param month the month-of-year to represent, from 1 (January) to 12 (December)
266 * @param dayOfMonth the day-of-month to represent, from 1 to 31
267 * @return the local date, not null
268 * @throws DateTimeException if the value of any field is out of range,
269 * or if the day-of-month is invalid for the month-year
270 */
271 public static LocalDate of(int year, int month, int dayOfMonth) {
272 YEAR.checkValidValue(year);
273 MONTH_OF_YEAR.checkValidValue(month);
274 DAY_OF_MONTH.checkValidValue(dayOfMonth);
275 return create(year, month, dayOfMonth);
276 }
277
278 //-----------------------------------------------------------------------
279 /**
280 * Obtains an instance of {@code LocalDate} from a year and day-of-year.
281 * <p>
282 * This returns a {@code LocalDate} with the specified year and day-of-year.
283 * The day-of-year must be valid for the year, otherwise an exception will be thrown.
284 *
285 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
286 * @param dayOfYear the day-of-year to represent, from 1 to 366
287 * @return the local date, not null
288 * @throws DateTimeException if the value of any field is out of range,
289 * or if the day-of-year is invalid for the year
290 */
291 public static LocalDate ofYearDay(int year, int dayOfYear) {
292 YEAR.checkValidValue(year);
293 DAY_OF_YEAR.checkValidValue(dayOfYear);
294 boolean leap = IsoChronology.INSTANCE.isLeapYear(year);
295 if (dayOfYear == 366 && leap == false) {
296 throw new DateTimeException("Invalid date 'DayOfYear 366' as '" + year + "' is not a leap year");
297 }
298 Month moy = Month.of((dayOfYear - 1) / 31 + 1);
299 int monthEnd = moy.firstDayOfYear(leap) + moy.length(leap) - 1;
300 if (dayOfYear > monthEnd) {
301 moy = moy.plus(1);
302 }
303 int dom = dayOfYear - moy.firstDayOfYear(leap) + 1;
304 return new LocalDate(year, moy.getValue(), dom);
305 }
306
307 //-----------------------------------------------------------------------
308 /**
309 * Obtains an instance of {@code LocalDate} from an {@code Instant} and zone ID.
310 * <p>
311 * This creates a local date based on the specified instant.
312 * First, the offset from UTC/Greenwich is obtained using the zone ID and instant,
313 * which is simple as there is only one valid offset for each instant.
314 * Then, the instant and offset are used to calculate the local date.
315 *
316 * @param instant the instant to create the date from, not null
317 * @param zone the time-zone, which may be an offset, not null
318 * @return the local date, not null
319 * @throws DateTimeException if the result exceeds the supported range
320 * @since 9
321 */
322 public static LocalDate ofInstant(Instant instant, ZoneId zone) {
323 Objects.requireNonNull(instant, "instant");
324 Objects.requireNonNull(zone, "zone");
325 ZoneRules rules = zone.getRules();
326 ZoneOffset offset = rules.getOffset(instant);
327 long localSecond = instant.getEpochSecond() + offset.getTotalSeconds();
328 long localEpochDay = Math.floorDiv(localSecond, SECONDS_PER_DAY);
329 return ofEpochDay(localEpochDay);
330 }
331
332 //-----------------------------------------------------------------------
333 /**
334 * Obtains an instance of {@code LocalDate} from the epoch day count.
335 * <p>
336 * This returns a {@code LocalDate} with the specified epoch-day.
337 * The {@link ChronoField#EPOCH_DAY EPOCH_DAY} is a simple incrementing count
338 * of days where day 0 is 1970-01-01. Negative numbers represent earlier days.
339 *
340 * @param epochDay the Epoch Day to convert, based on the epoch 1970-01-01
341 * @return the local date, not null
342 * @throws DateTimeException if the epoch day exceeds the supported date range
343 */
344 public static LocalDate ofEpochDay(long epochDay) {
345 EPOCH_DAY.checkValidValue(epochDay);
346 long zeroDay = epochDay + DAYS_0000_TO_1970;
347 // find the march-based year
348 zeroDay -= 60; // adjust to 0000-03-01 so leap day is at end of four year cycle
349 long adjust = 0;
350 if (zeroDay < 0) {
351 // adjust negative years to positive for calculation
352 long adjustCycles = (zeroDay + 1) / DAYS_PER_CYCLE - 1;
353 adjust = adjustCycles * 400;
354 zeroDay += -adjustCycles * DAYS_PER_CYCLE;
355 }
356 long yearEst = (400 * zeroDay + 591) / DAYS_PER_CYCLE;
357 long doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
358 if (doyEst < 0) {
359 // fix estimate
360 yearEst--;
361 doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
362 }
363 yearEst += adjust; // reset any negative year
364 int marchDoy0 = (int) doyEst;
365
366 // convert march-based values back to january-based
367 int marchMonth0 = (marchDoy0 * 5 + 2) / 153;
368 int month = marchMonth0 + 3;
369 if (month > 12) {
370 month -= 12;
371 }
372 int dom = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1;
373 if (marchDoy0 >= 306) {
374 yearEst++;
375 }
376
377 return new LocalDate((int)yearEst, month, dom);
378 }
379
380 //-----------------------------------------------------------------------
381 /**
382 * Obtains an instance of {@code LocalDate} from a temporal object.
383 * <p>
384 * This obtains a local date based on the specified temporal.
385 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
386 * which this factory converts to an instance of {@code LocalDate}.
387 * <p>
388 * The conversion uses the {@link TemporalQueries#localDate()} query, which relies
389 * on extracting the {@link ChronoField#EPOCH_DAY EPOCH_DAY} field.
390 * <p>
391 * This method matches the signature of the functional interface {@link TemporalQuery}
392 * allowing it to be used as a query via method reference, {@code LocalDate::from}.
393 *
394 * @param temporal the temporal object to convert, not null
395 * @return the local date, not null
396 * @throws DateTimeException if unable to convert to a {@code LocalDate}
397 */
398 public static LocalDate from(TemporalAccessor temporal) {
399 Objects.requireNonNull(temporal, "temporal");
400 LocalDate date = temporal.query(TemporalQueries.localDate());
401 if (date == null) {
402 throw new DateTimeException("Unable to obtain LocalDate from TemporalAccessor: " +
403 temporal + " of type " + temporal.getClass().getName());
404 }
405 return date;
406 }
407
408 //-----------------------------------------------------------------------
409 /**
410 * Obtains an instance of {@code LocalDate} from a text string such as {@code 2007-12-03}.
411 * <p>
412 * The string must represent a valid date and is parsed using
413 * {@link java.time.format.DateTimeFormatter#ISO_LOCAL_DATE}.
414 *
415 * @param text the text to parse such as "2007-12-03", not null
416 * @return the parsed local date, not null
417 * @throws DateTimeParseException if the text cannot be parsed
418 */
419 public static LocalDate parse(CharSequence text) {
420 return parse(text, DateTimeFormatter.ISO_LOCAL_DATE);
421 }
422
423 /**
424 * Obtains an instance of {@code LocalDate} from a text string using a specific formatter.
425 * <p>
426 * The text is parsed using the formatter, returning a date.
427 *
428 * @param text the text to parse, not null
429 * @param formatter the formatter to use, not null
430 * @return the parsed local date, not null
431 * @throws DateTimeParseException if the text cannot be parsed
432 */
433 public static LocalDate parse(CharSequence text, DateTimeFormatter formatter) {
434 Objects.requireNonNull(formatter, "formatter");
435 return formatter.parse(text, LocalDate::from);
436 }
437
438 //-----------------------------------------------------------------------
439 /**
440 * Creates a local date from the year, month and day fields.
441 *
442 * @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
443 * @param month the month-of-year to represent, from 1 to 12, validated
444 * @param dayOfMonth the day-of-month to represent, validated from 1 to 31
445 * @return the local date, not null
446 * @throws DateTimeException if the day-of-month is invalid for the month-year
447 */
448 private static LocalDate create(int year, int month, int dayOfMonth) {
449 if (dayOfMonth > 28) {
450 int dom = switch (month) {
451 case 2 -> (IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
452 case 4, 6, 9, 11 -> 30;
453 default -> 31;
454 };
455 if (dayOfMonth > dom) {
456 if (dayOfMonth == 29) {
457 throw new DateTimeException("Invalid date 'February 29' as '" + year + "' is not a leap year");
458 } else {
459 throw new DateTimeException("Invalid date '" + Month.of(month).name() + " " + dayOfMonth + "'");
460 }
461 }
462 }
463 return new LocalDate(year, month, dayOfMonth);
464 }
465
466 /**
467 * Resolves the date, resolving days past the end of month.
468 *
469 * @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
470 * @param month the month-of-year to represent, validated from 1 to 12
471 * @param day the day-of-month to represent, validated from 1 to 31
472 * @return the resolved date, not null
473 */
474 private static LocalDate resolvePreviousValid(int year, int month, int day) {
475 switch (month) {
476 case 2 -> day = Math.min(day, IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
477 case 4, 6, 9, 11 -> day = Math.min(day, 30);
478 }
479 return new LocalDate(year, month, day);
480 }
481
482 /**
483 * Constructor, previously validated.
484 *
485 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
486 * @param month the month-of-year to represent, not null
487 * @param dayOfMonth the day-of-month to represent, valid for year-month, from 1 to 31
488 */
489 private LocalDate(int year, int month, int dayOfMonth) {
490 this.year = year;
491 this.month = (short) month;
492 this.day = (short) dayOfMonth;
493 }
494
495 //-----------------------------------------------------------------------
496 /**
497 * Checks if the specified field is supported.
498 * <p>
499 * This checks if this date can be queried for the specified field.
500 * If false, then calling the {@link #range(TemporalField) range},
501 * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
502 * methods will throw an exception.
503 * <p>
504 * If the field is a {@link ChronoField} then the query is implemented here.
505 * The supported fields are:
506 * <ul>
507 * <li>{@code DAY_OF_WEEK}
508 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH}
509 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR}
510 * <li>{@code DAY_OF_MONTH}
511 * <li>{@code DAY_OF_YEAR}
512 * <li>{@code EPOCH_DAY}
513 * <li>{@code ALIGNED_WEEK_OF_MONTH}
514 * <li>{@code ALIGNED_WEEK_OF_YEAR}
515 * <li>{@code MONTH_OF_YEAR}
516 * <li>{@code PROLEPTIC_MONTH}
517 * <li>{@code YEAR_OF_ERA}
518 * <li>{@code YEAR}
519 * <li>{@code ERA}
520 * </ul>
521 * All other {@code ChronoField} instances will return false.
522 * <p>
523 * If the field is not a {@code ChronoField}, then the result of this method
524 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
525 * passing {@code this} as the argument.
526 * Whether the field is supported is determined by the field.
527 *
528 * @param field the field to check, null returns false
529 * @return true if the field is supported on this date, false if not
530 */
531 @Override // override for Javadoc
532 public boolean isSupported(TemporalField field) {
533 return ChronoLocalDate.super.isSupported(field);
534 }
535
536 /**
537 * Checks if the specified unit is supported.
538 * <p>
539 * This checks if the specified unit can be added to, or subtracted from, this date.
540 * If false, then calling the {@link #plus(long, TemporalUnit)} and
541 * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
542 * <p>
543 * If the unit is a {@link ChronoUnit} then the query is implemented here.
544 * The supported units are:
545 * <ul>
546 * <li>{@code DAYS}
547 * <li>{@code WEEKS}
548 * <li>{@code MONTHS}
549 * <li>{@code YEARS}
550 * <li>{@code DECADES}
551 * <li>{@code CENTURIES}
552 * <li>{@code MILLENNIA}
553 * <li>{@code ERAS}
554 * </ul>
555 * All other {@code ChronoUnit} instances will return false.
556 * <p>
557 * If the unit is not a {@code ChronoUnit}, then the result of this method
558 * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
559 * passing {@code this} as the argument.
560 * Whether the unit is supported is determined by the unit.
561 *
562 * @param unit the unit to check, null returns false
563 * @return true if the unit can be added/subtracted, false if not
564 */
565 @Override // override for Javadoc
566 public boolean isSupported(TemporalUnit unit) {
567 return ChronoLocalDate.super.isSupported(unit);
568 }
569
570 //-----------------------------------------------------------------------
571 /**
572 * Gets the range of valid values for the specified field.
573 * <p>
574 * The range object expresses the minimum and maximum valid values for a field.
575 * This date is used to enhance the accuracy of the returned range.
576 * If it is not possible to return the range, because the field is not supported
577 * or for some other reason, an exception is thrown.
578 * <p>
579 * If the field is a {@link ChronoField} then the query is implemented here.
580 * The {@link #isSupported(TemporalField) supported fields} will return
581 * appropriate range instances.
582 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
583 * <p>
584 * If the field is not a {@code ChronoField}, then the result of this method
585 * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
586 * passing {@code this} as the argument.
587 * Whether the range can be obtained is determined by the field.
588 *
589 * @param field the field to query the range for, not null
590 * @return the range of valid values for the field, not null
591 * @throws DateTimeException if the range for the field cannot be obtained
592 * @throws UnsupportedTemporalTypeException if the field is not supported
593 */
594 @Override
595 public ValueRange range(TemporalField field) {
596 if (field instanceof ChronoField chronoField) {
597 if (chronoField.isDateBased()) {
598 return switch (chronoField) {
599 case DAY_OF_MONTH -> ValueRange.of(1, lengthOfMonth());
600 case DAY_OF_YEAR -> ValueRange.of(1, lengthOfYear());
601 case ALIGNED_WEEK_OF_MONTH -> ValueRange.of(1, getMonth() == Month.FEBRUARY && !isLeapYear() ? 4 : 5);
602 case YEAR_OF_ERA -> (getYear() <= 0 ? ValueRange.of(1, Year.MAX_VALUE + 1) : ValueRange.of(1, Year.MAX_VALUE));
603 default -> field.range();
604 };
605 }
606 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
607 }
608 return field.rangeRefinedBy(this);
609 }
610
611 /**
612 * Gets the value of the specified field from this date as an {@code int}.
613 * <p>
614 * This queries this date for the value of the specified field.
615 * The returned value will always be within the valid range of values for the field.
616 * If it is not possible to return the value, because the field is not supported
617 * or for some other reason, an exception is thrown.
618 * <p>
619 * If the field is a {@link ChronoField} then the query is implemented here.
620 * The {@link #isSupported(TemporalField) supported fields} will return valid
621 * values based on this date, except {@code EPOCH_DAY} and {@code PROLEPTIC_MONTH}
622 * which are too large to fit in an {@code int} and throw an {@code UnsupportedTemporalTypeException}.
623 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
624 * <p>
625 * If the field is not a {@code ChronoField}, then the result of this method
626 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
627 * passing {@code this} as the argument. Whether the value can be obtained,
628 * and what the value represents, is determined by the field.
629 *
630 * @param field the field to get, not null
631 * @return the value for the field
632 * @throws DateTimeException if a value for the field cannot be obtained or
633 * the value is outside the range of valid values for the field
634 * @throws UnsupportedTemporalTypeException if the field is not supported or
635 * the range of values exceeds an {@code int}
636 * @throws ArithmeticException if numeric overflow occurs
637 */
638 @Override // override for Javadoc and performance
639 public int get(TemporalField field) {
640 if (field instanceof ChronoField) {
641 return get0(field);
642 }
643 return ChronoLocalDate.super.get(field);
644 }
645
646 /**
647 * Gets the value of the specified field from this date as a {@code long}.
648 * <p>
649 * This queries this date for the value of the specified field.
650 * If it is not possible to return the value, because the field is not supported
651 * or for some other reason, an exception is thrown.
652 * <p>
653 * If the field is a {@link ChronoField} then the query is implemented here.
654 * The {@link #isSupported(TemporalField) supported fields} will return valid
655 * values based on this date.
656 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
657 * <p>
658 * If the field is not a {@code ChronoField}, then the result of this method
659 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
660 * passing {@code this} as the argument. Whether the value can be obtained,
661 * and what the value represents, is determined by the field.
662 *
663 * @param field the field to get, not null
664 * @return the value for the field
665 * @throws DateTimeException if a value for the field cannot be obtained
666 * @throws UnsupportedTemporalTypeException if the field is not supported
667 * @throws ArithmeticException if numeric overflow occurs
668 */
669 @Override
670 public long getLong(TemporalField field) {
671 if (field instanceof ChronoField) {
672 if (field == EPOCH_DAY) {
673 return toEpochDay();
674 }
675 if (field == PROLEPTIC_MONTH) {
676 return getProlepticMonth();
677 }
678 return get0(field);
679 }
680 return field.getFrom(this);
681 }
682
683 private int get0(TemporalField field) {
684 return switch ((ChronoField) field) {
685 case DAY_OF_WEEK -> getDayOfWeek().getValue();
686 case ALIGNED_DAY_OF_WEEK_IN_MONTH -> ((day - 1) % 7) + 1;
687 case ALIGNED_DAY_OF_WEEK_IN_YEAR -> ((getDayOfYear() - 1) % 7) + 1;
688 case DAY_OF_MONTH -> day;
689 case DAY_OF_YEAR -> getDayOfYear();
690 case EPOCH_DAY -> throw new UnsupportedTemporalTypeException("Invalid field 'EpochDay' for get() method, use getLong() instead");
691 case ALIGNED_WEEK_OF_MONTH -> ((day - 1) / 7) + 1;
692 case ALIGNED_WEEK_OF_YEAR -> ((getDayOfYear() - 1) / 7) + 1;
693 case MONTH_OF_YEAR -> month;
694 case PROLEPTIC_MONTH -> throw new UnsupportedTemporalTypeException("Invalid field 'ProlepticMonth' for get() method, use getLong() instead");
695 case YEAR_OF_ERA -> (year >= 1 ? year : 1 - year);
696 case YEAR -> year;
697 case ERA -> (year >= 1 ? 1 : 0);
698 default -> throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
699 };
700 }
701
702 private long getProlepticMonth() {
703 return (year * 12L + month - 1);
704 }
705
706 //-----------------------------------------------------------------------
707 /**
708 * Gets the chronology of this date, which is the ISO calendar system.
709 * <p>
710 * The {@code Chronology} represents the calendar system in use.
711 * The ISO-8601 calendar system is the modern civil calendar system used today
712 * in most of the world. It is equivalent to the proleptic Gregorian calendar
713 * system, in which today's rules for leap years are applied for all time.
714 *
715 * @return the ISO chronology, not null
716 */
717 @Override
718 public IsoChronology getChronology() {
719 return IsoChronology.INSTANCE;
720 }
721
722 /**
723 * Gets the era applicable at this date.
724 * <p>
725 * The official ISO-8601 standard does not define eras, however {@code IsoChronology} does.
726 * It defines two eras, 'CE' from year one onwards and 'BCE' from year zero backwards.
727 * Since dates before the Julian-Gregorian cutover are not in line with history,
728 * the cutover between 'BCE' and 'CE' is also not aligned with the commonly used
729 * eras, often referred to using 'BC' and 'AD'.
730 * <p>
731 * Users of this class should typically ignore this method as it exists primarily
732 * to fulfill the {@link ChronoLocalDate} contract where it is necessary to support
733 * the Japanese calendar system.
734 *
735 * @return the IsoEra applicable at this date, not null
736 */
737 @Override // override for Javadoc
738 public IsoEra getEra() {
739 return (getYear() >= 1 ? IsoEra.CE : IsoEra.BCE);
740 }
741
742 /**
743 * Gets the year field.
744 * <p>
745 * This method returns the primitive {@code int} value for the year.
746 * <p>
747 * The year returned by this method is proleptic as per {@code get(YEAR)}.
748 * To obtain the year-of-era, use {@code get(YEAR_OF_ERA)}.
749 *
750 * @return the year, from MIN_YEAR to MAX_YEAR
751 */
752 public int getYear() {
753 return year;
754 }
755
756 /**
757 * Gets the month-of-year field from 1 to 12.
758 * <p>
759 * This method returns the month as an {@code int} from 1 to 12.
760 * Application code is frequently clearer if the enum {@link Month}
761 * is used by calling {@link #getMonth()}.
762 *
763 * @return the month-of-year, from 1 to 12
764 * @see #getMonth()
765 */
766 public int getMonthValue() {
767 return month;
768 }
769
770 /**
771 * Gets the month-of-year field using the {@code Month} enum.
772 * <p>
773 * This method returns the enum {@link Month} for the month.
774 * This avoids confusion as to what {@code int} values mean.
775 * If you need access to the primitive {@code int} value then the enum
776 * provides the {@link Month#getValue() int value}.
777 *
778 * @return the month-of-year, not null
779 * @see #getMonthValue()
780 */
781 public Month getMonth() {
782 return Month.of(month);
783 }
784
785 /**
786 * Gets the day-of-month field.
787 * <p>
788 * This method returns the primitive {@code int} value for the day-of-month.
789 *
790 * @return the day-of-month, from 1 to 31
791 */
792 public int getDayOfMonth() {
793 return day;
794 }
795
796 /**
797 * Gets the day-of-year field.
798 * <p>
799 * This method returns the primitive {@code int} value for the day-of-year.
800 *
801 * @return the day-of-year, from 1 to 365, or 366 in a leap year
802 */
803 public int getDayOfYear() {
804 return getMonth().firstDayOfYear(isLeapYear()) + day - 1;
805 }
806
807 /**
808 * Gets the day-of-week field, which is an enum {@code DayOfWeek}.
809 * <p>
810 * This method returns the enum {@link DayOfWeek} for the day-of-week.
811 * This avoids confusion as to what {@code int} values mean.
812 * If you need access to the primitive {@code int} value then the enum
813 * provides the {@link DayOfWeek#getValue() int value}.
814 * <p>
815 * Additional information can be obtained from the {@code DayOfWeek}.
816 * This includes textual names of the values.
817 *
818 * @return the day-of-week, not null
819 */
820 public DayOfWeek getDayOfWeek() {
821 int dow0 = Math.floorMod(toEpochDay() + 3, 7);
822 return DayOfWeek.of(dow0 + 1);
823 }
824
825 //-----------------------------------------------------------------------
826 /**
827 * Checks if the year is a leap year, according to the ISO proleptic
828 * calendar system rules.
829 * <p>
830 * This method applies the current rules for leap years across the whole time-line.
831 * In general, a year is a leap year if it is divisible by four without
832 * remainder. However, years divisible by 100, are not leap years, with
833 * the exception of years divisible by 400 which are.
834 * <p>
835 * For example, 1904 is a leap year it is divisible by 4.
836 * 1900 was not a leap year as it is divisible by 100, however 2000 was a
837 * leap year as it is divisible by 400.
838 * <p>
839 * The calculation is proleptic - applying the same rules into the far future and far past.
840 * This is historically inaccurate, but is correct for the ISO-8601 standard.
841 *
842 * @return true if the year is leap, false otherwise
843 */
844 @Override // override for Javadoc and performance
845 public boolean isLeapYear() {
846 return IsoChronology.INSTANCE.isLeapYear(year);
847 }
848
849 /**
850 * Returns the length of the month represented by this date.
851 * <p>
852 * This returns the length of the month in days.
853 * For example, a date in January would return 31.
854 *
855 * @return the length of the month in days
856 */
857 @Override
858 public int lengthOfMonth() {
859 return switch (month) {
860 case 2 -> (isLeapYear() ? 29 : 28);
861 case 4, 6, 9, 11 -> 30;
862 default -> 31;
863 };
864 }
865
866 /**
867 * Returns the length of the year represented by this date.
868 * <p>
869 * This returns the length of the year in days, either 365 or 366.
870 *
871 * @return 366 if the year is leap, 365 otherwise
872 */
873 @Override // override for Javadoc and performance
874 public int lengthOfYear() {
875 return (isLeapYear() ? 366 : 365);
876 }
877
878 //-----------------------------------------------------------------------
879 /**
880 * Returns an adjusted copy of this date.
881 * <p>
882 * This returns a {@code LocalDate}, based on this one, with the date adjusted.
883 * The adjustment takes place using the specified adjuster strategy object.
884 * Read the documentation of the adjuster to understand what adjustment will be made.
885 * <p>
886 * A simple adjuster might simply set the one of the fields, such as the year field.
887 * A more complex adjuster might set the date to the last day of the month.
888 * <p>
889 * A selection of common adjustments is provided in
890 * {@link java.time.temporal.TemporalAdjusters TemporalAdjusters}.
891 * These include finding the "last day of the month" and "next Wednesday".
892 * Key date-time classes also implement the {@code TemporalAdjuster} interface,
893 * such as {@link Month} and {@link java.time.MonthDay MonthDay}.
894 * The adjuster is responsible for handling special cases, such as the varying
895 * lengths of month and leap years.
896 * <p>
897 * For example this code returns a date on the last day of July:
898 * <pre>
899 * import static java.time.Month.*;
900 * import static java.time.temporal.TemporalAdjusters.*;
901 *
902 * result = localDate.with(JULY).with(lastDayOfMonth());
903 * </pre>
904 * <p>
905 * The result of this method is obtained by invoking the
906 * {@link TemporalAdjuster#adjustInto(Temporal)} method on the
907 * specified adjuster passing {@code this} as the argument.
908 * <p>
909 * This instance is immutable and unaffected by this method call.
910 *
911 * @param adjuster the adjuster to use, not null
912 * @return a {@code LocalDate} based on {@code this} with the adjustment made, not null
913 * @throws DateTimeException if the adjustment cannot be made
914 * @throws ArithmeticException if numeric overflow occurs
915 */
916 @Override
917 public LocalDate with(TemporalAdjuster adjuster) {
918 // optimizations
919 if (adjuster instanceof LocalDate) {
920 return (LocalDate) adjuster;
921 }
922 return (LocalDate) adjuster.adjustInto(this);
923 }
924
925 /**
926 * Returns a copy of this date with the specified field set to a new value.
927 * <p>
928 * This returns a {@code LocalDate}, based on this one, with the value
929 * for the specified field changed.
930 * This can be used to change any supported field, such as the year, month or day-of-month.
931 * If it is not possible to set the value, because the field is not supported or for
932 * some other reason, an exception is thrown.
933 * <p>
934 * In some cases, changing the specified field can cause the resulting date to become invalid,
935 * such as changing the month from 31st January to February would make the day-of-month invalid.
936 * In cases like this, the field is responsible for resolving the date. Typically it will choose
937 * the previous valid date, which would be the last valid day of February in this example.
938 * <p>
939 * If the field is a {@link ChronoField} then the adjustment is implemented here.
940 * The supported fields behave as follows:
941 * <ul>
942 * <li>{@code DAY_OF_WEEK} -
943 * Returns a {@code LocalDate} with the specified day-of-week.
944 * The date is adjusted up to 6 days forward or backward within the boundary
945 * of a Monday to Sunday week.
946 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH} -
947 * Returns a {@code LocalDate} with the specified aligned-day-of-week.
948 * The date is adjusted to the specified month-based aligned-day-of-week.
949 * Aligned weeks are counted such that the first week of a given month starts
950 * on the first day of that month.
951 * This may cause the date to be moved up to 6 days into the following month.
952 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR} -
953 * Returns a {@code LocalDate} with the specified aligned-day-of-week.
954 * The date is adjusted to the specified year-based aligned-day-of-week.
955 * Aligned weeks are counted such that the first week of a given year starts
956 * on the first day of that year.
957 * This may cause the date to be moved up to 6 days into the following year.
958 * <li>{@code DAY_OF_MONTH} -
959 * Returns a {@code LocalDate} with the specified day-of-month.
960 * The month and year will be unchanged. If the day-of-month is invalid for the
961 * year and month, then a {@code DateTimeException} is thrown.
962 * <li>{@code DAY_OF_YEAR} -
963 * Returns a {@code LocalDate} with the specified day-of-year.
964 * The year will be unchanged. If the day-of-year is invalid for the
965 * year, then a {@code DateTimeException} is thrown.
966 * <li>{@code EPOCH_DAY} -
967 * Returns a {@code LocalDate} with the specified epoch-day.
968 * This completely replaces the date and is equivalent to {@link #ofEpochDay(long)}.
969 * <li>{@code ALIGNED_WEEK_OF_MONTH} -
970 * Returns a {@code LocalDate} with the specified aligned-week-of-month.
971 * Aligned weeks are counted such that the first week of a given month starts
972 * on the first day of that month.
973 * This adjustment moves the date in whole week chunks to match the specified week.
974 * The result will have the same day-of-week as this date.
975 * This may cause the date to be moved into the following month.
976 * <li>{@code ALIGNED_WEEK_OF_YEAR} -
977 * Returns a {@code LocalDate} with the specified aligned-week-of-year.
978 * Aligned weeks are counted such that the first week of a given year starts
979 * on the first day of that year.
980 * This adjustment moves the date in whole week chunks to match the specified week.
981 * The result will have the same day-of-week as this date.
982 * This may cause the date to be moved into the following year.
983 * <li>{@code MONTH_OF_YEAR} -
984 * Returns a {@code LocalDate} with the specified month-of-year.
985 * The year will be unchanged. The day-of-month will also be unchanged,
986 * unless it would be invalid for the new month and year. In that case, the
987 * day-of-month is adjusted to the maximum valid value for the new month and year.
988 * <li>{@code PROLEPTIC_MONTH} -
989 * Returns a {@code LocalDate} with the specified proleptic-month.
990 * The day-of-month will be unchanged, unless it would be invalid for the new month
991 * and year. In that case, the day-of-month is adjusted to the maximum valid value
992 * for the new month and year.
993 * <li>{@code YEAR_OF_ERA} -
994 * Returns a {@code LocalDate} with the specified year-of-era.
995 * The era and month will be unchanged. The day-of-month will also be unchanged,
996 * unless it would be invalid for the new month and year. In that case, the
997 * day-of-month is adjusted to the maximum valid value for the new month and year.
998 * <li>{@code YEAR} -
999 * Returns a {@code LocalDate} with the specified year.
1000 * The month will be unchanged. The day-of-month will also be unchanged,
1001 * unless it would be invalid for the new month and year. In that case, the
1002 * day-of-month is adjusted to the maximum valid value for the new month and year.
1003 * <li>{@code ERA} -
1004 * Returns a {@code LocalDate} with the specified era.
1005 * The year-of-era and month will be unchanged. The day-of-month will also be unchanged,
1006 * unless it would be invalid for the new month and year. In that case, the
1007 * day-of-month is adjusted to the maximum valid value for the new month and year.
1008 * </ul>
1009 * <p>
1010 * In all cases, if the new value is outside the valid range of values for the field
1011 * then a {@code DateTimeException} will be thrown.
1012 * <p>
1013 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
1014 * <p>
1015 * If the field is not a {@code ChronoField}, then the result of this method
1016 * is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
1017 * passing {@code this} as the argument. In this case, the field determines
1018 * whether and how to adjust the instant.
1019 * <p>
1020 * This instance is immutable and unaffected by this method call.
1021 *
1022 * @param field the field to set in the result, not null
1023 * @param newValue the new value of the field in the result
1024 * @return a {@code LocalDate} based on {@code this} with the specified field set, not null
1025 * @throws DateTimeException if the field cannot be set
1026 * @throws UnsupportedTemporalTypeException if the field is not supported
1027 * @throws ArithmeticException if numeric overflow occurs
1028 */
1029 @Override
1030 public LocalDate with(TemporalField field, long newValue) {
1031 if (field instanceof ChronoField chronoField) {
1032 chronoField.checkValidValue(newValue);
1033 return switch (chronoField) {
1034 case DAY_OF_WEEK -> plusDays(newValue - getDayOfWeek().getValue());
1035 case ALIGNED_DAY_OF_WEEK_IN_MONTH -> plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_MONTH));
1036 case ALIGNED_DAY_OF_WEEK_IN_YEAR -> plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_YEAR));
1037 case DAY_OF_MONTH -> withDayOfMonth((int) newValue);
1038 case DAY_OF_YEAR -> withDayOfYear((int) newValue);
1039 case EPOCH_DAY -> LocalDate.ofEpochDay(newValue);
1040 case ALIGNED_WEEK_OF_MONTH -> plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_MONTH));
1041 case ALIGNED_WEEK_OF_YEAR -> plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_YEAR));
1042 case MONTH_OF_YEAR -> withMonth((int) newValue);
1043 case PROLEPTIC_MONTH -> plusMonths(newValue - getProlepticMonth());
1044 case YEAR_OF_ERA -> withYear((int) (year >= 1 ? newValue : 1 - newValue));
1045 case YEAR -> withYear((int) newValue);
1046 case ERA -> (getLong(ERA) == newValue ? this : withYear(1 - year));
1047 default -> throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
1048 };
1049 }
1050 return field.adjustInto(this, newValue);
1051 }
1052
1053 //-----------------------------------------------------------------------
1054 /**
1055 * Returns a copy of this {@code LocalDate} with the year altered.
1056 * <p>
1057 * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
1058 * <p>
1059 * This instance is immutable and unaffected by this method call.
1060 *
1061 * @param year the year to set in the result, from MIN_YEAR to MAX_YEAR
1062 * @return a {@code LocalDate} based on this date with the requested year, not null
1063 * @throws DateTimeException if the year value is invalid
1064 */
1065 public LocalDate withYear(int year) {
1066 if (this.year == year) {
1067 return this;
1068 }
1069 YEAR.checkValidValue(year);
1070 return resolvePreviousValid(year, month, day);
1071 }
1072
1073 /**
1074 * Returns a copy of this {@code LocalDate} with the month-of-year altered.
1075 * <p>
1076 * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
1077 * <p>
1078 * This instance is immutable and unaffected by this method call.
1079 *
1080 * @param month the month-of-year to set in the result, from 1 (January) to 12 (December)
1081 * @return a {@code LocalDate} based on this date with the requested month, not null
1082 * @throws DateTimeException if the month-of-year value is invalid
1083 */
1084 public LocalDate withMonth(int month) {
1085 if (this.month == month) {
1086 return this;
1087 }
1088 MONTH_OF_YEAR.checkValidValue(month);
1089 return resolvePreviousValid(year, month, day);
1090 }
1091
1092 /**
1093 * Returns a copy of this {@code LocalDate} with the day-of-month altered.
1094 * <p>
1095 * If the resulting date is invalid, an exception is thrown.
1096 * <p>
1097 * This instance is immutable and unaffected by this method call.
1098 *
1099 * @param dayOfMonth the day-of-month to set in the result, from 1 to 28-31
1100 * @return a {@code LocalDate} based on this date with the requested day, not null
1101 * @throws DateTimeException if the day-of-month value is invalid,
1102 * or if the day-of-month is invalid for the month-year
1103 */
1104 public LocalDate withDayOfMonth(int dayOfMonth) {
1105 if (this.day == dayOfMonth) {
1106 return this;
1107 }
1108 return of(year, month, dayOfMonth);
1109 }
1110
1111 /**
1112 * Returns a copy of this {@code LocalDate} with the day-of-year altered.
1113 * <p>
1114 * If the resulting date is invalid, an exception is thrown.
1115 * <p>
1116 * This instance is immutable and unaffected by this method call.
1117 *
1118 * @param dayOfYear the day-of-year to set in the result, from 1 to 365-366
1119 * @return a {@code LocalDate} based on this date with the requested day, not null
1120 * @throws DateTimeException if the day-of-year value is invalid,
1121 * or if the day-of-year is invalid for the year
1122 */
1123 public LocalDate withDayOfYear(int dayOfYear) {
1124 if (this.getDayOfYear() == dayOfYear) {
1125 return this;
1126 }
1127 return ofYearDay(year, dayOfYear);
1128 }
1129
1130 //-----------------------------------------------------------------------
1131 /**
1132 * Returns a copy of this date with the specified amount added.
1133 * <p>
1134 * This returns a {@code LocalDate}, based on this one, with the specified amount added.
1135 * The amount is typically {@link Period} but may be any other type implementing
1136 * the {@link TemporalAmount} interface.
1137 * <p>
1138 * The calculation is delegated to the amount object by calling
1139 * {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
1140 * to implement the addition in any way it wishes, however it typically
1141 * calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
1142 * of the amount implementation to determine if it can be successfully added.
1143 * <p>
1144 * This instance is immutable and unaffected by this method call.
1145 *
1146 * @param amountToAdd the amount to add, not null
1147 * @return a {@code LocalDate} based on this date with the addition made, not null
1148 * @throws DateTimeException if the addition cannot be made
1149 * @throws ArithmeticException if numeric overflow occurs
1150 */
1151 @Override
1152 public LocalDate plus(TemporalAmount amountToAdd) {
1153 if (amountToAdd instanceof Period periodToAdd) {
1154 return plusMonths(periodToAdd.toTotalMonths()).plusDays(periodToAdd.getDays());
1155 }
1156 Objects.requireNonNull(amountToAdd, "amountToAdd");
1157 return (LocalDate) amountToAdd.addTo(this);
1158 }
1159
1160 /**
1161 * Returns a copy of this date with the specified amount added.
1162 * <p>
1163 * This returns a {@code LocalDate}, based on this one, with the amount
1164 * in terms of the unit added. If it is not possible to add the amount, because the
1165 * unit is not supported or for some other reason, an exception is thrown.
1166 * <p>
1167 * In some cases, adding the amount can cause the resulting date to become invalid.
1168 * For example, adding one month to 31st January would result in 31st February.
1169 * In cases like this, the unit is responsible for resolving the date.
1170 * Typically it will choose the previous valid date, which would be the last valid
1171 * day of February in this example.
1172 * <p>
1173 * If the field is a {@link ChronoUnit} then the addition is implemented here.
1174 * The supported fields behave as follows:
1175 * <ul>
1176 * <li>{@code DAYS} -
1177 * Returns a {@code LocalDate} with the specified number of days added.
1178 * This is equivalent to {@link #plusDays(long)}.
1179 * <li>{@code WEEKS} -
1180 * Returns a {@code LocalDate} with the specified number of weeks added.
1181 * This is equivalent to {@link #plusWeeks(long)} and uses a 7 day week.
1182 * <li>{@code MONTHS} -
1183 * Returns a {@code LocalDate} with the specified number of months added.
1184 * This is equivalent to {@link #plusMonths(long)}.
1185 * The day-of-month will be unchanged unless it would be invalid for the new
1186 * month and year. In that case, the day-of-month is adjusted to the maximum
1187 * valid value for the new month and year.
1188 * <li>{@code YEARS} -
1189 * Returns a {@code LocalDate} with the specified number of years added.
1190 * This is equivalent to {@link #plusYears(long)}.
1191 * The day-of-month will be unchanged unless it would be invalid for the new
1192 * month and year. In that case, the day-of-month is adjusted to the maximum
1193 * valid value for the new month and year.
1194 * <li>{@code DECADES} -
1195 * Returns a {@code LocalDate} with the specified number of decades added.
1196 * This is equivalent to calling {@link #plusYears(long)} with the amount
1197 * multiplied by 10.
1198 * The day-of-month will be unchanged unless it would be invalid for the new
1199 * month and year. In that case, the day-of-month is adjusted to the maximum
1200 * valid value for the new month and year.
1201 * <li>{@code CENTURIES} -
1202 * Returns a {@code LocalDate} with the specified number of centuries added.
1203 * This is equivalent to calling {@link #plusYears(long)} with the amount
1204 * multiplied by 100.
1205 * The day-of-month will be unchanged unless it would be invalid for the new
1206 * month and year. In that case, the day-of-month is adjusted to the maximum
1207 * valid value for the new month and year.
1208 * <li>{@code MILLENNIA} -
1209 * Returns a {@code LocalDate} with the specified number of millennia added.
1210 * This is equivalent to calling {@link #plusYears(long)} with the amount
1211 * multiplied by 1,000.
1212 * The day-of-month will be unchanged unless it would be invalid for the new
1213 * month and year. In that case, the day-of-month is adjusted to the maximum
1214 * valid value for the new month and year.
1215 * <li>{@code ERAS} -
1216 * Returns a {@code LocalDate} with the specified number of eras added.
1217 * Only two eras are supported so the amount must be one, zero or minus one.
1218 * If the amount is non-zero then the year is changed such that the year-of-era
1219 * is unchanged.
1220 * The day-of-month will be unchanged unless it would be invalid for the new
1221 * month and year. In that case, the day-of-month is adjusted to the maximum
1222 * valid value for the new month and year.
1223 * </ul>
1224 * <p>
1225 * All other {@code ChronoUnit} instances will throw an {@code UnsupportedTemporalTypeException}.
1226 * <p>
1227 * If the field is not a {@code ChronoUnit}, then the result of this method
1228 * is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
1229 * passing {@code this} as the argument. In this case, the unit determines
1230 * whether and how to perform the addition.
1231 * <p>
1232 * This instance is immutable and unaffected by this method call.
1233 *
1234 * @param amountToAdd the amount of the unit to add to the result, may be negative
1235 * @param unit the unit of the amount to add, not null
1236 * @return a {@code LocalDate} based on this date with the specified amount added, not null
1237 * @throws DateTimeException if the addition cannot be made
1238 * @throws UnsupportedTemporalTypeException if the unit is not supported
1239 * @throws ArithmeticException if numeric overflow occurs
1240 */
1241 @Override
1242 public LocalDate plus(long amountToAdd, TemporalUnit unit) {
1243 if (unit instanceof ChronoUnit chronoUnit) {
1244 return switch (chronoUnit) {
1245 case DAYS -> plusDays(amountToAdd);
1246 case WEEKS -> plusWeeks(amountToAdd);
1247 case MONTHS -> plusMonths(amountToAdd);
1248 case YEARS -> plusYears(amountToAdd);
1249 case DECADES -> plusYears(Math.multiplyExact(amountToAdd, 10));
1250 case CENTURIES -> plusYears(Math.multiplyExact(amountToAdd, 100));
1251 case MILLENNIA -> plusYears(Math.multiplyExact(amountToAdd, 1000));
1252 case ERAS -> with(ERA, Math.addExact(getLong(ERA), amountToAdd));
1253 default -> throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1254 };
1255 }
1256 return unit.addTo(this, amountToAdd);
1257 }
1258
1259 //-----------------------------------------------------------------------
1260 /**
1261 * Returns a copy of this {@code LocalDate} with the specified number of years added.
1262 * <p>
1263 * This method adds the specified amount to the years field in three steps:
1264 * <ol>
1265 * <li>Add the input years to the year field</li>
1266 * <li>Check if the resulting date would be invalid</li>
1267 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1268 * </ol>
1269 * <p>
1270 * For example, 2008-02-29 (leap year) plus one year would result in the
1271 * invalid date 2009-02-29 (standard year). Instead of returning an invalid
1272 * result, the last valid day of the month, 2009-02-28, is selected instead.
1273 * <p>
1274 * This instance is immutable and unaffected by this method call.
1275 *
1276 * @param yearsToAdd the years to add, may be negative
1277 * @return a {@code LocalDate} based on this date with the years added, not null
1278 * @throws DateTimeException if the result exceeds the supported date range
1279 */
1280 public LocalDate plusYears(long yearsToAdd) {
1281 if (yearsToAdd == 0) {
1282 return this;
1283 }
1284 int newYear = YEAR.checkValidIntValue(year + yearsToAdd); // safe overflow
1285 return resolvePreviousValid(newYear, month, day);
1286 }
1287
1288 /**
1289 * Returns a copy of this {@code LocalDate} with the specified number of months added.
1290 * <p>
1291 * This method adds the specified amount to the months field in three steps:
1292 * <ol>
1293 * <li>Add the input months to the month-of-year field</li>
1294 * <li>Check if the resulting date would be invalid</li>
1295 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1296 * </ol>
1297 * <p>
1298 * For example, 2007-03-31 plus one month would result in the invalid date
1299 * 2007-04-31. Instead of returning an invalid result, the last valid day
1300 * of the month, 2007-04-30, is selected instead.
1301 * <p>
1302 * This instance is immutable and unaffected by this method call.
1303 *
1304 * @param monthsToAdd the months to add, may be negative
1305 * @return a {@code LocalDate} based on this date with the months added, not null
1306 * @throws DateTimeException if the result exceeds the supported date range
1307 */
1308 public LocalDate plusMonths(long monthsToAdd) {
1309 if (monthsToAdd == 0) {
1310 return this;
1311 }
1312 long monthCount = year * 12L + (month - 1);
1313 long calcMonths = monthCount + monthsToAdd; // safe overflow
1314 int newYear = YEAR.checkValidIntValue(Math.floorDiv(calcMonths, 12));
1315 int newMonth = Math.floorMod(calcMonths, 12) + 1;
1316 return resolvePreviousValid(newYear, newMonth, day);
1317 }
1318
1319 /**
1320 * Returns a copy of this {@code LocalDate} with the specified number of weeks added.
1321 * <p>
1322 * This method adds the specified amount in weeks to the days field incrementing
1323 * the month and year fields as necessary to ensure the result remains valid.
1324 * The result is only invalid if the maximum/minimum year is exceeded.
1325 * <p>
1326 * For example, 2008-12-31 plus one week would result in 2009-01-07.
1327 * <p>
1328 * This instance is immutable and unaffected by this method call.
1329 *
1330 * @param weeksToAdd the weeks to add, may be negative
1331 * @return a {@code LocalDate} based on this date with the weeks added, not null
1332 * @throws DateTimeException if the result exceeds the supported date range
1333 */
1334 public LocalDate plusWeeks(long weeksToAdd) {
1335 return plusDays(Math.multiplyExact(weeksToAdd, 7));
1336 }
1337
1338 /**
1339 * Returns a copy of this {@code LocalDate} with the specified number of days added.
1340 * <p>
1341 * This method adds the specified amount to the days field incrementing the
1342 * month and year fields as necessary to ensure the result remains valid.
1343 * The result is only invalid if the maximum/minimum year is exceeded.
1344 * <p>
1345 * For example, 2008-12-31 plus one day would result in 2009-01-01.
1346 * <p>
1347 * This instance is immutable and unaffected by this method call.
1348 *
1349 * @param daysToAdd the days to add, may be negative
1350 * @return a {@code LocalDate} based on this date with the days added, not null
1351 * @throws DateTimeException if the result exceeds the supported date range
1352 */
1353 public LocalDate plusDays(long daysToAdd) {
1354 if (daysToAdd == 0) {
1355 return this;
1356 }
1357 long dom = day + daysToAdd;
1358 if (dom > 0) {
1359 if (dom <= 28) {
1360 return new LocalDate(year, month, (int) dom);
1361 } else if (dom <= 59) { // 59th Jan is 28th Feb, 59th Feb is 31st Mar
1362 long monthLen = lengthOfMonth();
1363 if (dom <= monthLen) {
1364 return new LocalDate(year, month, (int) dom);
1365 } else if (month < 12) {
1366 return new LocalDate(year, month + 1, (int) (dom - monthLen));
1367 } else {
1368 YEAR.checkValidValue(year + 1);
1369 return new LocalDate(year + 1, 1, (int) (dom - monthLen));
1370 }
1371 }
1372 }
1373
1374 long mjDay = Math.addExact(toEpochDay(), daysToAdd);
1375 return LocalDate.ofEpochDay(mjDay);
1376 }
1377
1378 //-----------------------------------------------------------------------
1379 /**
1380 * Returns a copy of this date with the specified amount subtracted.
1381 * <p>
1382 * This returns a {@code LocalDate}, based on this one, with the specified amount subtracted.
1383 * The amount is typically {@link Period} but may be any other type implementing
1384 * the {@link TemporalAmount} interface.
1385 * <p>
1386 * The calculation is delegated to the amount object by calling
1387 * {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
1388 * to implement the subtraction in any way it wishes, however it typically
1389 * calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
1390 * of the amount implementation to determine if it can be successfully subtracted.
1391 * <p>
1392 * This instance is immutable and unaffected by this method call.
1393 *
1394 * @param amountToSubtract the amount to subtract, not null
1395 * @return a {@code LocalDate} based on this date with the subtraction made, not null
1396 * @throws DateTimeException if the subtraction cannot be made
1397 * @throws ArithmeticException if numeric overflow occurs
1398 */
1399 @Override
1400 public LocalDate minus(TemporalAmount amountToSubtract) {
1401 if (amountToSubtract instanceof Period periodToSubtract) {
1402 return minusMonths(periodToSubtract.toTotalMonths()).minusDays(periodToSubtract.getDays());
1403 }
1404 Objects.requireNonNull(amountToSubtract, "amountToSubtract");
1405 return (LocalDate) amountToSubtract.subtractFrom(this);
1406 }
1407
1408 /**
1409 * Returns a copy of this date with the specified amount subtracted.
1410 * <p>
1411 * This returns a {@code LocalDate}, based on this one, with the amount
1412 * in terms of the unit subtracted. If it is not possible to subtract the amount,
1413 * because the unit is not supported or for some other reason, an exception is thrown.
1414 * <p>
1415 * This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
1416 * See that method for a full description of how addition, and thus subtraction, works.
1417 * <p>
1418 * This instance is immutable and unaffected by this method call.
1419 *
1420 * @param amountToSubtract the amount of the unit to subtract from the result, may be negative
1421 * @param unit the unit of the amount to subtract, not null
1422 * @return a {@code LocalDate} based on this date with the specified amount subtracted, not null
1423 * @throws DateTimeException if the subtraction cannot be made
1424 * @throws UnsupportedTemporalTypeException if the unit is not supported
1425 * @throws ArithmeticException if numeric overflow occurs
1426 */
1427 @Override
1428 public LocalDate minus(long amountToSubtract, TemporalUnit unit) {
1429 return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
1430 }
1431
1432 //-----------------------------------------------------------------------
1433 /**
1434 * Returns a copy of this {@code LocalDate} with the specified number of years subtracted.
1435 * <p>
1436 * This method subtracts the specified amount from the years field in three steps:
1437 * <ol>
1438 * <li>Subtract the input years from the year field</li>
1439 * <li>Check if the resulting date would be invalid</li>
1440 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1441 * </ol>
1442 * <p>
1443 * For example, 2008-02-29 (leap year) minus one year would result in the
1444 * invalid date 2007-02-29 (standard year). Instead of returning an invalid
1445 * result, the last valid day of the month, 2007-02-28, is selected instead.
1446 * <p>
1447 * This instance is immutable and unaffected by this method call.
1448 *
1449 * @param yearsToSubtract the years to subtract, may be negative
1450 * @return a {@code LocalDate} based on this date with the years subtracted, not null
1451 * @throws DateTimeException if the result exceeds the supported date range
1452 */
1453 public LocalDate minusYears(long yearsToSubtract) {
1454 return (yearsToSubtract == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-yearsToSubtract));
1455 }
1456
1457 /**
1458 * Returns a copy of this {@code LocalDate} with the specified number of months subtracted.
1459 * <p>
1460 * This method subtracts the specified amount from the months field in three steps:
1461 * <ol>
1462 * <li>Subtract the input months from the month-of-year field</li>
1463 * <li>Check if the resulting date would be invalid</li>
1464 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1465 * </ol>
1466 * <p>
1467 * For example, 2007-03-31 minus one month would result in the invalid date
1468 * 2007-02-31. Instead of returning an invalid result, the last valid day
1469 * of the month, 2007-02-28, is selected instead.
1470 * <p>
1471 * This instance is immutable and unaffected by this method call.
1472 *
1473 * @param monthsToSubtract the months to subtract, may be negative
1474 * @return a {@code LocalDate} based on this date with the months subtracted, not null
1475 * @throws DateTimeException if the result exceeds the supported date range
1476 */
1477 public LocalDate minusMonths(long monthsToSubtract) {
1478 return (monthsToSubtract == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-monthsToSubtract));
1479 }
1480
1481 /**
1482 * Returns a copy of this {@code LocalDate} with the specified number of weeks subtracted.
1483 * <p>
1484 * This method subtracts the specified amount in weeks from the days field decrementing
1485 * the month and year fields as necessary to ensure the result remains valid.
1486 * The result is only invalid if the maximum/minimum year is exceeded.
1487 * <p>
1488 * For example, 2009-01-07 minus one week would result in 2008-12-31.
1489 * <p>
1490 * This instance is immutable and unaffected by this method call.
1491 *
1492 * @param weeksToSubtract the weeks to subtract, may be negative
1493 * @return a {@code LocalDate} based on this date with the weeks subtracted, not null
1494 * @throws DateTimeException if the result exceeds the supported date range
1495 */
1496 public LocalDate minusWeeks(long weeksToSubtract) {
1497 return (weeksToSubtract == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeksToSubtract));
1498 }
1499
1500 /**
1501 * Returns a copy of this {@code LocalDate} with the specified number of days subtracted.
1502 * <p>
1503 * This method subtracts the specified amount from the days field decrementing the
1504 * month and year fields as necessary to ensure the result remains valid.
1505 * The result is only invalid if the maximum/minimum year is exceeded.
1506 * <p>
1507 * For example, 2009-01-01 minus one day would result in 2008-12-31.
1508 * <p>
1509 * This instance is immutable and unaffected by this method call.
1510 *
1511 * @param daysToSubtract the days to subtract, may be negative
1512 * @return a {@code LocalDate} based on this date with the days subtracted, not null
1513 * @throws DateTimeException if the result exceeds the supported date range
1514 */
1515 public LocalDate minusDays(long daysToSubtract) {
1516 return (daysToSubtract == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-daysToSubtract));
1517 }
1518
1519 //-----------------------------------------------------------------------
1520 /**
1521 * Queries this date using the specified query.
1522 * <p>
1523 * This queries this date using the specified query strategy object.
1524 * The {@code TemporalQuery} object defines the logic to be used to
1525 * obtain the result. Read the documentation of the query to understand
1526 * what the result of this method will be.
1527 * <p>
1528 * The result of this method is obtained by invoking the
1529 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
1530 * specified query passing {@code this} as the argument.
1531 *
1532 * @param <R> the type of the result
1533 * @param query the query to invoke, not null
1534 * @return the query result, null may be returned (defined by the query)
1535 * @throws DateTimeException if unable to query (defined by the query)
1536 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
1537 */
1538 @SuppressWarnings("unchecked")
1539 @Override
1540 public <R> R query(TemporalQuery<R> query) {
1541 if (query == TemporalQueries.localDate()) {
1542 return (R) this;
1543 }
1544 return ChronoLocalDate.super.query(query);
1545 }
1546
1547 /**
1548 * Adjusts the specified temporal object to have the same date as this object.
1549 * <p>
1550 * This returns a temporal object of the same observable type as the input
1551 * with the date changed to be the same as this.
1552 * <p>
1553 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
1554 * passing {@link ChronoField#EPOCH_DAY} as the field.
1555 * <p>
1556 * In most cases, it is clearer to reverse the calling pattern by using
1557 * {@link Temporal#with(TemporalAdjuster)}:
1558 * <pre>
1559 * // these two lines are equivalent, but the second approach is recommended
1560 * temporal = thisLocalDate.adjustInto(temporal);
1561 * temporal = temporal.with(thisLocalDate);
1562 * </pre>
1563 * <p>
1564 * This instance is immutable and unaffected by this method call.
1565 *
1566 * @param temporal the target object to be adjusted, not null
1567 * @return the adjusted object, not null
1568 * @throws DateTimeException if unable to make the adjustment
1569 * @throws ArithmeticException if numeric overflow occurs
1570 */
1571 @Override // override for Javadoc
1572 public Temporal adjustInto(Temporal temporal) {
1573 return ChronoLocalDate.super.adjustInto(temporal);
1574 }
1575
1576 /**
1577 * Calculates the amount of time until another date in terms of the specified unit.
1578 * <p>
1579 * This calculates the amount of time between two {@code LocalDate}
1580 * objects in terms of a single {@code TemporalUnit}.
1581 * The start and end points are {@code this} and the specified date.
1582 * The result will be negative if the end is before the start.
1583 * The {@code Temporal} passed to this method is converted to a
1584 * {@code LocalDate} using {@link #from(TemporalAccessor)}.
1585 * For example, the amount in days between two dates can be calculated
1586 * using {@code startDate.until(endDate, DAYS)}.
1587 * <p>
1588 * The calculation returns a whole number, representing the number of
1589 * complete units between the two dates.
1590 * For example, the amount in months between 2012-06-15 and 2012-08-14
1591 * will only be one month as it is one day short of two months.
1592 * <p>
1593 * There are two equivalent ways of using this method.
1594 * The first is to invoke this method.
1595 * The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
1596 * <pre>
1597 * // these two lines are equivalent
1598 * amount = start.until(end, MONTHS);
1599 * amount = MONTHS.between(start, end);
1600 * </pre>
1601 * The choice should be made based on which makes the code more readable.
1602 * <p>
1603 * The calculation is implemented in this method for {@link ChronoUnit}.
1604 * The units {@code DAYS}, {@code WEEKS}, {@code MONTHS}, {@code YEARS},
1605 * {@code DECADES}, {@code CENTURIES}, {@code MILLENNIA} and {@code ERAS}
1606 * are supported. Other {@code ChronoUnit} values will throw an exception.
1607 * <p>
1608 * If the unit is not a {@code ChronoUnit}, then the result of this method
1609 * is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
1610 * passing {@code this} as the first argument and the converted input temporal
1611 * as the second argument.
1612 * <p>
1613 * This instance is immutable and unaffected by this method call.
1614 *
1615 * @param endExclusive the end date, exclusive, which is converted to a {@code LocalDate}, not null
1616 * @param unit the unit to measure the amount in, not null
1617 * @return the amount of time between this date and the end date
1618 * @throws DateTimeException if the amount cannot be calculated, or the end
1619 * temporal cannot be converted to a {@code LocalDate}
1620 * @throws UnsupportedTemporalTypeException if the unit is not supported
1621 * @throws ArithmeticException if numeric overflow occurs
1622 */
1623 @Override
1624 public long until(Temporal endExclusive, TemporalUnit unit) {
1625 LocalDate end = LocalDate.from(endExclusive);
1626 if (unit instanceof ChronoUnit chronoUnit) {
1627 return switch (chronoUnit) {
1628 case DAYS -> daysUntil(end);
1629 case WEEKS -> daysUntil(end) / 7;
1630 case MONTHS -> monthsUntil(end);
1631 case YEARS -> monthsUntil(end) / 12;
1632 case DECADES -> monthsUntil(end) / 120;
1633 case CENTURIES -> monthsUntil(end) / 1200;
1634 case MILLENNIA -> monthsUntil(end) / 12000;
1635 case ERAS -> end.getLong(ERA) - getLong(ERA);
1636 default -> throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1637 };
1638 }
1639 return unit.between(this, end);
1640 }
1641
1642 long daysUntil(LocalDate end) {
1643 return end.toEpochDay() - toEpochDay(); // no overflow
1644 }
1645
1646 private long monthsUntil(LocalDate end) {
1647 long packed1 = getProlepticMonth() * 32L + getDayOfMonth(); // no overflow
1648 long packed2 = end.getProlepticMonth() * 32L + end.getDayOfMonth(); // no overflow
1649 return (packed2 - packed1) / 32;
1650 }
1651
1652 /**
1653 * Calculates the period between this date and another date as a {@code Period}.
1654 * <p>
1655 * This calculates the period between two dates in terms of years, months and days.
1656 * The start and end points are {@code this} and the specified date.
1657 * The result will be negative if the end is before the start.
1658 * The negative sign will be the same in each of year, month and day.
1659 * <p>
1660 * The calculation is performed using the ISO calendar system.
1661 * If necessary, the input date will be converted to ISO.
1662 * <p>
1663 * The start date is included, but the end date is not.
1664 * The period is calculated by removing complete months, then calculating
1665 * the remaining number of days, adjusting to ensure that both have the same sign.
1666 * The number of months is then normalized into years and months based on a 12 month year.
1667 * A month is considered to be complete if the end day-of-month is greater
1668 * than or equal to the start day-of-month.
1669 * For example, from {@code 2010-01-15} to {@code 2011-03-18} is "1 year, 2 months and 3 days".
1670 * <p>
1671 * There are two equivalent ways of using this method.
1672 * The first is to invoke this method.
1673 * The second is to use {@link Period#between(LocalDate, LocalDate)}:
1674 * <pre>
1675 * // these two lines are equivalent
1676 * period = start.until(end);
1677 * period = Period.between(start, end);
1678 * </pre>
1679 * The choice should be made based on which makes the code more readable.
1680 *
1681 * @param endDateExclusive the end date, exclusive, which may be in any chronology, not null
1682 * @return the period between this date and the end date, not null
1683 */
1684 @Override
1685 public Period until(ChronoLocalDate endDateExclusive) {
1686 LocalDate end = LocalDate.from(endDateExclusive);
1687 long totalMonths = end.getProlepticMonth() - this.getProlepticMonth(); // safe
1688 int days = end.day - this.day;
1689 if (totalMonths > 0 && days < 0) {
1690 totalMonths--;
1691 LocalDate calcDate = this.plusMonths(totalMonths);
1692 days = (int) (end.toEpochDay() - calcDate.toEpochDay()); // safe
1693 } else if (totalMonths < 0 && days > 0) {
1694 totalMonths++;
1695 days -= end.lengthOfMonth();
1696 }
1697 long years = totalMonths / 12; // safe
1698 int months = (int) (totalMonths % 12); // safe
1699 return Period.of(Math.toIntExact(years), months, days);
1700 }
1701
1702 /**
1703 * Returns a sequential ordered stream of dates. The returned stream starts from this date
1704 * (inclusive) and goes to {@code endExclusive} (exclusive) by an incremental step of 1 day.
1705 * <p>
1706 * This method is equivalent to {@code datesUntil(endExclusive, Period.ofDays(1))}.
1707 *
1708 * @param endExclusive the end date, exclusive, not null
1709 * @return a sequential {@code Stream} for the range of {@code LocalDate} values
1710 * @throws IllegalArgumentException if end date is before this date
1711 * @since 9
1712 */
1713 public Stream<LocalDate> datesUntil(LocalDate endExclusive) {
1714 long end = endExclusive.toEpochDay();
1715 long start = toEpochDay();
1716 if (end < start) {
1717 throw new IllegalArgumentException(endExclusive + " < " + this);
1718 }
1719 return LongStream.range(start, end).mapToObj(LocalDate::ofEpochDay);
1720 }
1721
1722 /**
1723 * Returns a sequential ordered stream of dates by given incremental step. The returned stream
1724 * starts from this date (inclusive) and goes to {@code endExclusive} (exclusive).
1725 * <p>
1726 * The n-th date which appears in the stream is equal to {@code this.plus(step.multipliedBy(n))}
1727 * (but the result of step multiplication never overflows). For example, if this date is
1728 * {@code 2015-01-31}, the end date is {@code 2015-05-01} and the step is 1 month, then the
1729 * stream contains {@code 2015-01-31}, {@code 2015-02-28}, {@code 2015-03-31}, and
1730 * {@code 2015-04-30}.
1731 *
1732 * @param endExclusive the end date, exclusive, not null
1733 * @param step the non-zero, non-negative {@code Period} which represents the step.
1734 * @return a sequential {@code Stream} for the range of {@code LocalDate} values
1735 * @throws IllegalArgumentException if step is zero, or {@code step.getDays()} and
1736 * {@code step.toTotalMonths()} have opposite sign, or end date is before this date
1737 * and step is positive, or end date is after this date and step is negative
1738 * @since 9
1739 */
1740 public Stream<LocalDate> datesUntil(LocalDate endExclusive, Period step) {
1741 if (step.isZero()) {
1742 throw new IllegalArgumentException("step is zero");
1743 }
1744 long end = endExclusive.toEpochDay();
1745 long start = toEpochDay();
1746 long until = end - start;
1747 long months = step.toTotalMonths();
1748 long days = step.getDays();
1749 if ((months < 0 && days > 0) || (months > 0 && days < 0)) {
1750 throw new IllegalArgumentException("period months and days are of opposite sign");
1751 }
1752 if (until == 0) {
1753 return Stream.empty();
1754 }
1755 int sign = months > 0 || days > 0 ? 1 : -1;
1756 if (sign < 0 ^ until < 0) {
1757 throw new IllegalArgumentException(endExclusive + (sign < 0 ? " > " : " < ") + this);
1758 }
1759 if (months == 0) {
1760 long steps = (until - sign) / days; // non-negative
1761 return LongStream.rangeClosed(0, steps).mapToObj(
1762 n -> LocalDate.ofEpochDay(start + n * days));
1763 }
1764 // 48699/1600 = 365.2425/12, no overflow, non-negative result
1765 long steps = until * 1600 / (months * 48699 + days * 1600) + 1;
1766 long addMonths = months * steps;
1767 long addDays = days * steps;
1768 long maxAddMonths = months > 0 ? MAX.getProlepticMonth() - getProlepticMonth()
1769 : getProlepticMonth() - MIN.getProlepticMonth();
1770 // adjust steps estimation
1771 if (addMonths * sign > maxAddMonths
1772 || (plusMonths(addMonths).toEpochDay() + addDays) * sign >= end * sign) {
1773 steps--;
1774 addMonths -= months;
1775 addDays -= days;
1776 if (addMonths * sign > maxAddMonths
1777 || (plusMonths(addMonths).toEpochDay() + addDays) * sign >= end * sign) {
1778 steps--;
1779 }
1780 }
1781 return LongStream.rangeClosed(0, steps).mapToObj(
1782 n -> this.plusMonths(months * n).plusDays(days * n));
1783 }
1784
1785 /**
1786 * Formats this date using the specified formatter.
1787 * <p>
1788 * This date will be passed to the formatter to produce a string.
1789 *
1790 * @param formatter the formatter to use, not null
1791 * @return the formatted date string, not null
1792 * @throws DateTimeException if an error occurs during printing
1793 */
1794 @Override // override for Javadoc and performance
1795 public String format(DateTimeFormatter formatter) {
1796 Objects.requireNonNull(formatter, "formatter");
1797 return formatter.format(this);
1798 }
1799
1800 //-----------------------------------------------------------------------
1801 /**
1802 * Combines this date with a time to create a {@code LocalDateTime}.
1803 * <p>
1804 * This returns a {@code LocalDateTime} formed from this date at the specified time.
1805 * All possible combinations of date and time are valid.
1806 *
1807 * @param time the time to combine with, not null
1808 * @return the local date-time formed from this date and the specified time, not null
1809 */
1810 @Override
1811 public LocalDateTime atTime(LocalTime time) {
1812 return LocalDateTime.of(this, time);
1813 }
1814
1815 /**
1816 * Combines this date with a time to create a {@code LocalDateTime}.
1817 * <p>
1818 * This returns a {@code LocalDateTime} formed from this date at the
1819 * specified hour and minute.
1820 * The seconds and nanosecond fields will be set to zero.
1821 * The individual time fields must be within their valid range.
1822 * All possible combinations of date and time are valid.
1823 *
1824 * @param hour the hour-of-day to use, from 0 to 23
1825 * @param minute the minute-of-hour to use, from 0 to 59
1826 * @return the local date-time formed from this date and the specified time, not null
1827 * @throws DateTimeException if the value of any field is out of range
1828 */
1829 public LocalDateTime atTime(int hour, int minute) {
1830 return atTime(LocalTime.of(hour, minute));
1831 }
1832
1833 /**
1834 * Combines this date with a time to create a {@code LocalDateTime}.
1835 * <p>
1836 * This returns a {@code LocalDateTime} formed from this date at the
1837 * specified hour, minute and second.
1838 * The nanosecond field will be set to zero.
1839 * The individual time fields must be within their valid range.
1840 * All possible combinations of date and time are valid.
1841 *
1842 * @param hour the hour-of-day to use, from 0 to 23
1843 * @param minute the minute-of-hour to use, from 0 to 59
1844 * @param second the second-of-minute to represent, from 0 to 59
1845 * @return the local date-time formed from this date and the specified time, not null
1846 * @throws DateTimeException if the value of any field is out of range
1847 */
1848 public LocalDateTime atTime(int hour, int minute, int second) {
1849 return atTime(LocalTime.of(hour, minute, second));
1850 }
1851
1852 /**
1853 * Combines this date with a time to create a {@code LocalDateTime}.
1854 * <p>
1855 * This returns a {@code LocalDateTime} formed from this date at the
1856 * specified hour, minute, second and nanosecond.
1857 * The individual time fields must be within their valid range.
1858 * All possible combinations of date and time are valid.
1859 *
1860 * @param hour the hour-of-day to use, from 0 to 23
1861 * @param minute the minute-of-hour to use, from 0 to 59
1862 * @param second the second-of-minute to represent, from 0 to 59
1863 * @param nanoOfSecond the nano-of-second to represent, from 0 to 999,999,999
1864 * @return the local date-time formed from this date and the specified time, not null
1865 * @throws DateTimeException if the value of any field is out of range
1866 */
1867 public LocalDateTime atTime(int hour, int minute, int second, int nanoOfSecond) {
1868 return atTime(LocalTime.of(hour, minute, second, nanoOfSecond));
1869 }
1870
1871 /**
1872 * Combines this date with an offset time to create an {@code OffsetDateTime}.
1873 * <p>
1874 * This returns an {@code OffsetDateTime} formed from this date at the specified time.
1875 * All possible combinations of date and time are valid.
1876 *
1877 * @param time the time to combine with, not null
1878 * @return the offset date-time formed from this date and the specified time, not null
1879 */
1880 public OffsetDateTime atTime(OffsetTime time) {
1881 return OffsetDateTime.of(LocalDateTime.of(this, time.toLocalTime()), time.getOffset());
1882 }
1883
1884 /**
1885 * Combines this date with the time of midnight to create a {@code LocalDateTime}
1886 * at the start of this date.
1887 * <p>
1888 * This returns a {@code LocalDateTime} formed from this date at the time of
1889 * midnight, 00:00, at the start of this date.
1890 *
1891 * @return the local date-time of midnight at the start of this date, not null
1892 */
1893 public LocalDateTime atStartOfDay() {
1894 return LocalDateTime.of(this, LocalTime.MIDNIGHT);
1895 }
1896
1897 /**
1898 * Returns a zoned date-time from this date at the earliest valid time according
1899 * to the rules in the time-zone.
1900 * <p>
1901 * Time-zone rules, such as daylight savings, mean that not every local date-time
1902 * is valid for the specified zone, thus the local date-time may not be midnight.
1903 * <p>
1904 * In most cases, there is only one valid offset for a local date-time.
1905 * In the case of an overlap, there are two valid offsets, and the earlier one is used,
1906 * corresponding to the first occurrence of midnight on the date.
1907 * In the case of a gap, the zoned date-time will represent the instant just after the gap.
1908 * <p>
1909 * If the zone ID is a {@link ZoneOffset}, then the result always has a time of midnight.
1910 * <p>
1911 * To convert to a specific time in a given time-zone call {@link #atTime(LocalTime)}
1912 * followed by {@link LocalDateTime#atZone(ZoneId)}.
1913 *
1914 * @param zone the zone ID to use, not null
1915 * @return the zoned date-time formed from this date and the earliest valid time for the zone, not null
1916 */
1917 public ZonedDateTime atStartOfDay(ZoneId zone) {
1918 Objects.requireNonNull(zone, "zone");
1919 // need to handle case where there is a gap from 11:30 to 00:30
1920 // standard ZDT factory would result in 01:00 rather than 00:30
1921 LocalDateTime ldt = atTime(LocalTime.MIDNIGHT);
1922 if (!(zone instanceof ZoneOffset)) {
1923 ZoneRules rules = zone.getRules();
1924 ZoneOffsetTransition trans = rules.getTransition(ldt);
1925 if (trans != null && trans.isGap()) {
1926 ldt = trans.getDateTimeAfter();
1927 }
1928 }
1929 return ZonedDateTime.of(ldt, zone);
1930 }
1931
1932 //-----------------------------------------------------------------------
1933 @Override
1934 public long toEpochDay() {
1935 long y = year;
1936 long m = month;
1937 long total = 0;
1938 total += 365 * y;
1939 if (y >= 0) {
1940 total += (y + 3) / 4 - (y + 99) / 100 + (y + 399) / 400;
1941 } else {
1942 total -= y / -4 - y / -100 + y / -400;
1943 }
1944 total += ((367 * m - 362) / 12);
1945 total += day - 1;
1946 if (m > 2) {
1947 total--;
1948 if (isLeapYear() == false) {
1949 total--;
1950 }
1951 }
1952 return total - DAYS_0000_TO_1970;
1953 }
1954
1955 /**
1956 * Converts this {@code LocalDate} to the number of seconds since the epoch
1957 * of 1970-01-01T00:00:00Z.
1958 * <p>
1959 * This combines this local date with the specified time and
1960 * offset to calculate the epoch-second value, which is the
1961 * number of elapsed seconds from 1970-01-01T00:00:00Z.
1962 * Instants on the time-line after the epoch are positive, earlier
1963 * are negative.
1964 *
1965 * @param time the local time, not null
1966 * @param offset the zone offset, not null
1967 * @return the number of seconds since the epoch of 1970-01-01T00:00:00Z, may be negative
1968 * @since 9
1969 */
1970 public long toEpochSecond(LocalTime time, ZoneOffset offset) {
1971 Objects.requireNonNull(time, "time");
1972 Objects.requireNonNull(offset, "offset");
1973 long secs = toEpochDay() * SECONDS_PER_DAY + time.toSecondOfDay();
1974 secs -= offset.getTotalSeconds();
1975 return secs;
1976 }
1977
1978 //-----------------------------------------------------------------------
1979 /**
1980 * Compares this date to another date.
1981 * <p>
1982 * The comparison is primarily based on the date, from earliest to latest.
1983 * It is "consistent with equals", as defined by {@link Comparable}.
1984 * <p>
1985 * If all the dates being compared are instances of {@code LocalDate},
1986 * then the comparison will be entirely based on the date.
1987 * If some dates being compared are in different chronologies, then the
1988 * chronology is also considered, see {@link java.time.chrono.ChronoLocalDate#compareTo}.
1989 *
1990 * @param other the other date to compare to, not null
1991 * @return the comparator value, that is the comparison of this local date with
1992 * the {@code other} local date and this chronology with the {@code other} chronology,
1993 * in order, returning the first non-zero result, and otherwise returning zero
1994 * @see #isBefore
1995 * @see #isAfter
1996 */
1997 @Override // override for Javadoc and performance
1998 public int compareTo(ChronoLocalDate other) {
1999 if (other instanceof LocalDate) {
2000 return compareTo0((LocalDate) other);
2001 }
2002 return ChronoLocalDate.super.compareTo(other);
2003 }
2004
2005 int compareTo0(LocalDate otherDate) {
2006 int cmp = (year - otherDate.year);
2007 if (cmp == 0) {
2008 cmp = (month - otherDate.month);
2009 if (cmp == 0) {
2010 cmp = (day - otherDate.day);
2011 }
2012 }
2013 return cmp;
2014 }
2015
2016 /**
2017 * Checks if this date is after the specified date.
2018 * <p>
2019 * This checks to see if this date represents a point on the
2020 * local time-line after the other date.
2021 * <pre>
2022 * LocalDate a = LocalDate.of(2012, 6, 30);
2023 * LocalDate b = LocalDate.of(2012, 7, 1);
2024 * a.isAfter(b) == false
2025 * a.isAfter(a) == false
2026 * b.isAfter(a) == true
2027 * </pre>
2028 * <p>
2029 * This method only considers the position of the two dates on the local time-line.
2030 * It does not take into account the chronology, or calendar system.
2031 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)},
2032 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2033 *
2034 * @param other the other date to compare to, not null
2035 * @return true if this date is after the specified date
2036 */
2037 @Override // override for Javadoc and performance
2038 public boolean isAfter(ChronoLocalDate other) {
2039 if (other instanceof LocalDate) {
2040 return compareTo0((LocalDate) other) > 0;
2041 }
2042 return ChronoLocalDate.super.isAfter(other);
2043 }
2044
2045 /**
2046 * Checks if this date is before the specified date.
2047 * <p>
2048 * This checks to see if this date represents a point on the
2049 * local time-line before the other date.
2050 * <pre>
2051 * LocalDate a = LocalDate.of(2012, 6, 30);
2052 * LocalDate b = LocalDate.of(2012, 7, 1);
2053 * a.isBefore(b) == true
2054 * a.isBefore(a) == false
2055 * b.isBefore(a) == false
2056 * </pre>
2057 * <p>
2058 * This method only considers the position of the two dates on the local time-line.
2059 * It does not take into account the chronology, or calendar system.
2060 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)},
2061 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2062 *
2063 * @param other the other date to compare to, not null
2064 * @return true if this date is before the specified date
2065 */
2066 @Override // override for Javadoc and performance
2067 public boolean isBefore(ChronoLocalDate other) {
2068 if (other instanceof LocalDate) {
2069 return compareTo0((LocalDate) other) < 0;
2070 }
2071 return ChronoLocalDate.super.isBefore(other);
2072 }
2073
2074 /**
2075 * Checks if this date is equal to the specified date.
2076 * <p>
2077 * This checks to see if this date represents the same point on the
2078 * local time-line as the other date.
2079 * <pre>
2080 * LocalDate a = LocalDate.of(2012, 6, 30);
2081 * LocalDate b = LocalDate.of(2012, 7, 1);
2082 * a.isEqual(b) == false
2083 * a.isEqual(a) == true
2084 * b.isEqual(a) == false
2085 * </pre>
2086 * <p>
2087 * This method only considers the position of the two dates on the local time-line.
2088 * It does not take into account the chronology, or calendar system.
2089 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)}
2090 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2091 *
2092 * @param other the other date to compare to, not null
2093 * @return true if this date is equal to the specified date
2094 */
2095 @Override // override for Javadoc and performance
2096 public boolean isEqual(ChronoLocalDate other) {
2097 if (other instanceof LocalDate) {
2098 return compareTo0((LocalDate) other) == 0;
2099 }
2100 return ChronoLocalDate.super.isEqual(other);
2101 }
2102
2103 //-----------------------------------------------------------------------
2104 /**
2105 * Checks if this date is equal to another date.
2106 * <p>
2107 * Compares this {@code LocalDate} with another ensuring that the date is the same.
2108 * <p>
2109 * Only objects of type {@code LocalDate} are compared, other types return false.
2110 * To compare the dates of two {@code TemporalAccessor} instances, including dates
2111 * in two different chronologies, use {@link ChronoField#EPOCH_DAY} as a comparator.
2112 *
2113 * @param obj the object to check, null returns false
2114 * @return true if this is equal to the other date
2115 */
2116 @Override
2117 public boolean equals(Object obj) {
2118 if (this == obj) {
2119 return true;
2120 }
2121 if (obj instanceof LocalDate) {
2122 return compareTo0((LocalDate) obj) == 0;
2123 }
2124 return false;
2125 }
2126
2127 /**
2128 * A hash code for this date.
2129 *
2130 * @return a suitable hash code
2131 */
2132 @Override
2133 public int hashCode() {
2134 int yearValue = year;
2135 int monthValue = month;
2136 int dayValue = day;
2137 return (yearValue & 0xFFFFF800) ^ ((yearValue << 11) + (monthValue << 6) + (dayValue));
2138 }
2139
2140 //-----------------------------------------------------------------------
2141 /**
2142 * Outputs this date as a {@code String}, such as {@code 2007-12-03}.
2143 * <p>
2144 * The output will be in the ISO-8601 format {@code uuuu-MM-dd}.
2145 *
2146 * @return a string representation of this date, not null
2147 */
2148 @Override
2149 public String toString() {
2150 int yearValue = year;
2151 int monthValue = month;
2152 int dayValue = day;
2153 int absYear = Math.abs(yearValue);
2154 StringBuilder buf = new StringBuilder(10);
2155 if (absYear < 1000) {
2156 if (yearValue < 0) {
2157 buf.append(yearValue - 10000).deleteCharAt(1);
2158 } else {
2159 buf.append(yearValue + 10000).deleteCharAt(0);
2160 }
2161 } else {
2162 if (yearValue > 9999) {
2163 buf.append('+');
2164 }
2165 buf.append(yearValue);
2166 }
2167 return buf.append(monthValue < 10 ? "-0" : "-")
2168 .append(monthValue)
2169 .append(dayValue < 10 ? "-0" : "-")
2170 .append(dayValue)
2171 .toString();
2172 }
2173
2174 //-----------------------------------------------------------------------
2175 /**
2176 * Writes the object using a
2177 * <a href="{@docRoot}/serialized-form.html#java.time.Ser">dedicated serialized form</a>.
2178 * @serialData
2179 * <pre>
2180 * out.writeByte(3); // identifies a LocalDate
2181 * out.writeInt(year);
2182 * out.writeByte(month);
2183 * out.writeByte(day);
2184 * </pre>
2185 *
2186 * @return the instance of {@code Ser}, not null
2187 */
2188 @java.io.Serial
2189 private Object writeReplace() {
2190 return new Ser(Ser.LOCAL_DATE_TYPE, this);
2191 }
2192
2193 /**
2194 * Defend against malicious streams.
2195 *
2196 * @param s the stream to read
2197 * @throws InvalidObjectException always
2198 */
2199 @java.io.Serial
2200 private void readObject(ObjectInputStream s) throws InvalidObjectException {
2201 throw new InvalidObjectException("Deserialization via serialization delegate");
2202 }
2203
2204 void writeExternal(DataOutput out) throws IOException {
2205 out.writeInt(year);
2206 out.writeByte(month);
2207 out.writeByte(day);
2208 }
2209
2210 static LocalDate readExternal(DataInput in) throws IOException {
2211 int year = in.readInt();
2212 int month = in.readByte();
2213 int dayOfMonth = in.readByte();
2214 return LocalDate.of(year, month, dayOfMonth);
2215 }
2216
2217 }