1 /*
2 * Copyright (c) 2012, 2018, 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 *
127 * <p>
128 * This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
129 * class; use of identity-sensitive operations (including reference equality
130 * ({@code ==}), identity hash code, or synchronization) on instances of
131 * {@code LocalDate} may have unpredictable results and should be avoided.
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 public final class LocalDate
140 implements Temporal, TemporalAdjuster, ChronoLocalDate, Serializable {
141
142 /**
143 * The minimum supported {@code LocalDate}, '-999999999-01-01'.
144 * This could be used by an application as a "far past" date.
145 */
146 public static final LocalDate MIN = LocalDate.of(Year.MIN_VALUE, 1, 1);
147 /**
148 * The maximum supported {@code LocalDate}, '+999999999-12-31'.
149 * This could be used by an application as a "far future" date.
150 */
151 public static final LocalDate MAX = LocalDate.of(Year.MAX_VALUE, 12, 31);
152 /**
153 * The epoch year {@code LocalDate}, '1970-01-01'.
154 */
155 public static final LocalDate EPOCH = LocalDate.of(1970, 1, 1);
156
157 /**
158 * Serialization version.
159 */
160 @java.io.Serial
161 private static final long serialVersionUID = 2942565459149668126L;
162 /**
163 * The number of days in a 400 year cycle.
164 */
165 private static final int DAYS_PER_CYCLE = 146097;
166 /**
167 * The number of days from year zero to year 1970.
168 * There are five 400 year cycles from year zero to 2000.
169 * There are 7 leap years from 1970 to 2000.
170 */
171 static final long DAYS_0000_TO_1970 = (DAYS_PER_CYCLE * 5L) - (30L * 365L + 7L);
172
173 /**
174 * The year.
175 */
176 private final int year;
177 /**
178 * The month-of-year.
179 */
180 private final short month;
181 /**
182 * The day-of-month.
183 */
184 private final short day;
185
186 //-----------------------------------------------------------------------
187 /**
188 * Obtains the current date from the system clock in the default time-zone.
189 * <p>
190 * This will query the {@link Clock#systemDefaultZone() system clock} in the default
191 * time-zone to obtain the current date.
192 * <p>
193 * Using this method will prevent the ability to use an alternate clock for testing
194 * because the clock is hard-coded.
195 *
196 * @return the current date using the system clock and default time-zone, not null
197 */
198 public static LocalDate now() {
199 return now(Clock.systemDefaultZone());
200 }
201
202 /**
203 * Obtains the current date from the system clock in the specified time-zone.
204 * <p>
205 * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date.
206 * Specifying the time-zone avoids dependence on the default time-zone.
207 * <p>
208 * Using this method will prevent the ability to use an alternate clock for testing
209 * because the clock is hard-coded.
210 *
211 * @param zone the zone ID to use, not null
212 * @return the current date using the system clock, not null
213 */
214 public static LocalDate now(ZoneId zone) {
215 return now(Clock.system(zone));
216 }
217
218 /**
219 * Obtains the current date from the specified clock.
220 * <p>
221 * This will query the specified clock to obtain the current date - today.
222 * Using this method allows the use of an alternate clock for testing.
223 * The alternate clock may be introduced using {@link Clock dependency injection}.
224 *
225 * @param clock the clock to use, not null
226 * @return the current date, not null
227 */
228 public static LocalDate now(Clock clock) {
229 Objects.requireNonNull(clock, "clock");
230 final Instant now = clock.instant(); // called once
231 return ofInstant(now, clock.getZone());
232 }
233
234 //-----------------------------------------------------------------------
235 /**
236 * Obtains an instance of {@code LocalDate} from a year, month and day.
237 * <p>
238 * This returns a {@code LocalDate} with the specified year, month and day-of-month.
239 * The day must be valid for the year and month, otherwise an exception will be thrown.
240 *
241 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
242 * @param month the month-of-year to represent, not null
243 * @param dayOfMonth the day-of-month to represent, from 1 to 31
244 * @return the local date, not null
245 * @throws DateTimeException if the value of any field is out of range,
246 * or if the day-of-month is invalid for the month-year
247 */
248 public static LocalDate of(int year, Month month, int dayOfMonth) {
249 YEAR.checkValidValue(year);
250 Objects.requireNonNull(month, "month");
251 DAY_OF_MONTH.checkValidValue(dayOfMonth);
252 return create(year, month.getValue(), dayOfMonth);
253 }
254
255 /**
256 * Obtains an instance of {@code LocalDate} from a year, month and day.
257 * <p>
258 * This returns a {@code LocalDate} with the specified year, month and day-of-month.
259 * The day must be valid for the year and month, otherwise an exception will be thrown.
260 *
261 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
262 * @param month the month-of-year to represent, from 1 (January) to 12 (December)
263 * @param dayOfMonth the day-of-month to represent, from 1 to 31
264 * @return the local date, not null
265 * @throws DateTimeException if the value of any field is out of range,
266 * or if the day-of-month is invalid for the month-year
267 */
268 public static LocalDate of(int year, int month, int dayOfMonth) {
269 YEAR.checkValidValue(year);
270 MONTH_OF_YEAR.checkValidValue(month);
271 DAY_OF_MONTH.checkValidValue(dayOfMonth);
272 return create(year, month, dayOfMonth);
273 }
274
275 //-----------------------------------------------------------------------
276 /**
277 * Obtains an instance of {@code LocalDate} from a year and day-of-year.
278 * <p>
279 * This returns a {@code LocalDate} with the specified year and day-of-year.
280 * The day-of-year must be valid for the year, otherwise an exception will be thrown.
281 *
282 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
283 * @param dayOfYear the day-of-year to represent, from 1 to 366
284 * @return the local date, not null
285 * @throws DateTimeException if the value of any field is out of range,
286 * or if the day-of-year is invalid for the year
287 */
288 public static LocalDate ofYearDay(int year, int dayOfYear) {
289 YEAR.checkValidValue(year);
290 DAY_OF_YEAR.checkValidValue(dayOfYear);
291 boolean leap = IsoChronology.INSTANCE.isLeapYear(year);
292 if (dayOfYear == 366 && leap == false) {
293 throw new DateTimeException("Invalid date 'DayOfYear 366' as '" + year + "' is not a leap year");
294 }
295 Month moy = Month.of((dayOfYear - 1) / 31 + 1);
296 int monthEnd = moy.firstDayOfYear(leap) + moy.length(leap) - 1;
297 if (dayOfYear > monthEnd) {
298 moy = moy.plus(1);
299 }
300 int dom = dayOfYear - moy.firstDayOfYear(leap) + 1;
301 return new LocalDate(year, moy.getValue(), dom);
302 }
303
304 //-----------------------------------------------------------------------
305 /**
306 * Obtains an instance of {@code LocalDate} from an {@code Instant} and zone ID.
307 * <p>
308 * This creates a local date based on the specified instant.
309 * First, the offset from UTC/Greenwich is obtained using the zone ID and instant,
310 * which is simple as there is only one valid offset for each instant.
311 * Then, the instant and offset are used to calculate the local date.
312 *
313 * @param instant the instant to create the date from, not null
314 * @param zone the time-zone, which may be an offset, not null
315 * @return the local date, not null
316 * @throws DateTimeException if the result exceeds the supported range
317 * @since 9
318 */
319 public static LocalDate ofInstant(Instant instant, ZoneId zone) {
320 Objects.requireNonNull(instant, "instant");
321 Objects.requireNonNull(zone, "zone");
322 ZoneRules rules = zone.getRules();
323 ZoneOffset offset = rules.getOffset(instant);
324 long localSecond = instant.getEpochSecond() + offset.getTotalSeconds();
325 long localEpochDay = Math.floorDiv(localSecond, SECONDS_PER_DAY);
326 return ofEpochDay(localEpochDay);
327 }
328
329 //-----------------------------------------------------------------------
330 /**
331 * Obtains an instance of {@code LocalDate} from the epoch day count.
332 * <p>
333 * This returns a {@code LocalDate} with the specified epoch-day.
334 * The {@link ChronoField#EPOCH_DAY EPOCH_DAY} is a simple incrementing count
335 * of days where day 0 is 1970-01-01. Negative numbers represent earlier days.
336 *
337 * @param epochDay the Epoch Day to convert, based on the epoch 1970-01-01
338 * @return the local date, not null
339 * @throws DateTimeException if the epoch day exceeds the supported date range
340 */
341 public static LocalDate ofEpochDay(long epochDay) {
342 EPOCH_DAY.checkValidValue(epochDay);
343 long zeroDay = epochDay + DAYS_0000_TO_1970;
344 // find the march-based year
345 zeroDay -= 60; // adjust to 0000-03-01 so leap day is at end of four year cycle
346 long adjust = 0;
347 if (zeroDay < 0) {
348 // adjust negative years to positive for calculation
349 long adjustCycles = (zeroDay + 1) / DAYS_PER_CYCLE - 1;
350 adjust = adjustCycles * 400;
351 zeroDay += -adjustCycles * DAYS_PER_CYCLE;
352 }
353 long yearEst = (400 * zeroDay + 591) / DAYS_PER_CYCLE;
354 long doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
355 if (doyEst < 0) {
356 // fix estimate
357 yearEst--;
358 doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
359 }
360 yearEst += adjust; // reset any negative year
361 int marchDoy0 = (int) doyEst;
362
363 // convert march-based values back to january-based
364 int marchMonth0 = (marchDoy0 * 5 + 2) / 153;
365 int month = (marchMonth0 + 2) % 12 + 1;
366 int dom = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1;
367 yearEst += marchMonth0 / 10;
368
369 // check year now we are certain it is correct
370 int year = YEAR.checkValidIntValue(yearEst);
371 return new LocalDate(year, month, dom);
372 }
373
374 //-----------------------------------------------------------------------
375 /**
376 * Obtains an instance of {@code LocalDate} from a temporal object.
377 * <p>
378 * This obtains a local date based on the specified temporal.
379 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
380 * which this factory converts to an instance of {@code LocalDate}.
381 * <p>
382 * The conversion uses the {@link TemporalQueries#localDate()} query, which relies
383 * on extracting the {@link ChronoField#EPOCH_DAY EPOCH_DAY} field.
384 * <p>
385 * This method matches the signature of the functional interface {@link TemporalQuery}
386 * allowing it to be used as a query via method reference, {@code LocalDate::from}.
387 *
388 * @param temporal the temporal object to convert, not null
389 * @return the local date, not null
390 * @throws DateTimeException if unable to convert to a {@code LocalDate}
391 */
392 public static LocalDate from(TemporalAccessor temporal) {
393 Objects.requireNonNull(temporal, "temporal");
394 LocalDate date = temporal.query(TemporalQueries.localDate());
395 if (date == null) {
396 throw new DateTimeException("Unable to obtain LocalDate from TemporalAccessor: " +
397 temporal + " of type " + temporal.getClass().getName());
398 }
399 return date;
400 }
401
402 //-----------------------------------------------------------------------
403 /**
404 * Obtains an instance of {@code LocalDate} from a text string such as {@code 2007-12-03}.
405 * <p>
406 * The string must represent a valid date and is parsed using
407 * {@link java.time.format.DateTimeFormatter#ISO_LOCAL_DATE}.
408 *
409 * @param text the text to parse such as "2007-12-03", not null
410 * @return the parsed local date, not null
411 * @throws DateTimeParseException if the text cannot be parsed
412 */
413 public static LocalDate parse(CharSequence text) {
414 return parse(text, DateTimeFormatter.ISO_LOCAL_DATE);
415 }
416
417 /**
418 * Obtains an instance of {@code LocalDate} from a text string using a specific formatter.
419 * <p>
420 * The text is parsed using the formatter, returning a date.
421 *
422 * @param text the text to parse, not null
423 * @param formatter the formatter to use, not null
424 * @return the parsed local date, not null
425 * @throws DateTimeParseException if the text cannot be parsed
426 */
427 public static LocalDate parse(CharSequence text, DateTimeFormatter formatter) {
428 Objects.requireNonNull(formatter, "formatter");
429 return formatter.parse(text, LocalDate::from);
430 }
431
432 //-----------------------------------------------------------------------
433 /**
434 * Creates a local date from the year, month and day fields.
435 *
436 * @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
437 * @param month the month-of-year to represent, from 1 to 12, validated
438 * @param dayOfMonth the day-of-month to represent, validated from 1 to 31
439 * @return the local date, not null
440 * @throws DateTimeException if the day-of-month is invalid for the month-year
441 */
442 private static LocalDate create(int year, int month, int dayOfMonth) {
443 if (dayOfMonth > 28) {
444 int dom = 31;
445 switch (month) {
446 case 2:
447 dom = (IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
448 break;
449 case 4:
450 case 6:
451 case 9:
452 case 11:
453 dom = 30;
454 break;
455 }
456 if (dayOfMonth > dom) {
457 if (dayOfMonth == 29) {
458 throw new DateTimeException("Invalid date 'February 29' as '" + year + "' is not a leap year");
459 } else {
460 throw new DateTimeException("Invalid date '" + Month.of(month).name() + " " + dayOfMonth + "'");
461 }
462 }
463 }
464 return new LocalDate(year, month, dayOfMonth);
465 }
466
467 /**
468 * Resolves the date, resolving days past the end of month.
469 *
470 * @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
471 * @param month the month-of-year to represent, validated from 1 to 12
472 * @param day the day-of-month to represent, validated from 1 to 31
473 * @return the resolved date, not null
474 */
475 private static LocalDate resolvePreviousValid(int year, int month, int day) {
476 switch (month) {
477 case 2:
478 day = Math.min(day, IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
479 break;
480 case 4:
481 case 6:
482 case 9:
483 case 11:
484 day = Math.min(day, 30);
485 break;
486 }
487 return new LocalDate(year, month, day);
488 }
489
490 /**
491 * Constructor, previously validated.
492 *
493 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
494 * @param month the month-of-year to represent, not null
495 * @param dayOfMonth the day-of-month to represent, valid for year-month, from 1 to 31
496 */
497 private LocalDate(int year, int month, int dayOfMonth) {
498 this.year = year;
499 this.month = (short) month;
500 this.day = (short) dayOfMonth;
501 }
502
503 //-----------------------------------------------------------------------
504 /**
505 * Checks if the specified field is supported.
506 * <p>
507 * This checks if this date can be queried for the specified field.
508 * If false, then calling the {@link #range(TemporalField) range},
509 * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
510 * methods will throw an exception.
511 * <p>
512 * If the field is a {@link ChronoField} then the query is implemented here.
513 * The supported fields are:
514 * <ul>
515 * <li>{@code DAY_OF_WEEK}
516 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH}
517 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR}
518 * <li>{@code DAY_OF_MONTH}
519 * <li>{@code DAY_OF_YEAR}
520 * <li>{@code EPOCH_DAY}
521 * <li>{@code ALIGNED_WEEK_OF_MONTH}
522 * <li>{@code ALIGNED_WEEK_OF_YEAR}
523 * <li>{@code MONTH_OF_YEAR}
524 * <li>{@code PROLEPTIC_MONTH}
525 * <li>{@code YEAR_OF_ERA}
526 * <li>{@code YEAR}
527 * <li>{@code ERA}
528 * </ul>
529 * All other {@code ChronoField} instances will return false.
530 * <p>
531 * If the field is not a {@code ChronoField}, then the result of this method
532 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
533 * passing {@code this} as the argument.
534 * Whether the field is supported is determined by the field.
535 *
536 * @param field the field to check, null returns false
537 * @return true if the field is supported on this date, false if not
538 */
539 @Override // override for Javadoc
540 public boolean isSupported(TemporalField field) {
541 return ChronoLocalDate.super.isSupported(field);
542 }
543
544 /**
545 * Checks if the specified unit is supported.
546 * <p>
547 * This checks if the specified unit can be added to, or subtracted from, this date.
548 * If false, then calling the {@link #plus(long, TemporalUnit)} and
549 * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
550 * <p>
551 * If the unit is a {@link ChronoUnit} then the query is implemented here.
552 * The supported units are:
553 * <ul>
554 * <li>{@code DAYS}
555 * <li>{@code WEEKS}
556 * <li>{@code MONTHS}
557 * <li>{@code YEARS}
558 * <li>{@code DECADES}
559 * <li>{@code CENTURIES}
560 * <li>{@code MILLENNIA}
561 * <li>{@code ERAS}
562 * </ul>
563 * All other {@code ChronoUnit} instances will return false.
564 * <p>
565 * If the unit is not a {@code ChronoUnit}, then the result of this method
566 * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
567 * passing {@code this} as the argument.
568 * Whether the unit is supported is determined by the unit.
569 *
570 * @param unit the unit to check, null returns false
571 * @return true if the unit can be added/subtracted, false if not
572 */
573 @Override // override for Javadoc
574 public boolean isSupported(TemporalUnit unit) {
575 return ChronoLocalDate.super.isSupported(unit);
576 }
577
578 //-----------------------------------------------------------------------
579 /**
580 * Gets the range of valid values for the specified field.
581 * <p>
582 * The range object expresses the minimum and maximum valid values for a field.
583 * This date is used to enhance the accuracy of the returned range.
584 * If it is not possible to return the range, because the field is not supported
585 * or for some other reason, an exception is thrown.
586 * <p>
587 * If the field is a {@link ChronoField} then the query is implemented here.
588 * The {@link #isSupported(TemporalField) supported fields} will return
589 * appropriate range instances.
590 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
591 * <p>
592 * If the field is not a {@code ChronoField}, then the result of this method
593 * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
594 * passing {@code this} as the argument.
595 * Whether the range can be obtained is determined by the field.
596 *
597 * @param field the field to query the range for, not null
598 * @return the range of valid values for the field, not null
599 * @throws DateTimeException if the range for the field cannot be obtained
600 * @throws UnsupportedTemporalTypeException if the field is not supported
601 */
602 @Override
603 public ValueRange range(TemporalField field) {
604 if (field instanceof ChronoField) {
605 ChronoField f = (ChronoField) field;
606 if (f.isDateBased()) {
607 switch (f) {
608 case DAY_OF_MONTH: return ValueRange.of(1, lengthOfMonth());
609 case DAY_OF_YEAR: return ValueRange.of(1, lengthOfYear());
610 case ALIGNED_WEEK_OF_MONTH: return ValueRange.of(1, getMonth() == Month.FEBRUARY && isLeapYear() == false ? 4 : 5);
611 case YEAR_OF_ERA:
612 return (getYear() <= 0 ? ValueRange.of(1, Year.MAX_VALUE + 1) : ValueRange.of(1, Year.MAX_VALUE));
613 }
614 return field.range();
615 }
616 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
617 }
618 return field.rangeRefinedBy(this);
619 }
620
621 /**
622 * Gets the value of the specified field from this date as an {@code int}.
623 * <p>
624 * This queries this date for the value of the specified field.
625 * The returned value will always be within the valid range of values for the field.
626 * If it is not possible to return the value, because the field is not supported
627 * or for some other reason, an exception is thrown.
628 * <p>
629 * If the field is a {@link ChronoField} then the query is implemented here.
630 * The {@link #isSupported(TemporalField) supported fields} will return valid
631 * values based on this date, except {@code EPOCH_DAY} and {@code PROLEPTIC_MONTH}
632 * which are too large to fit in an {@code int} and throw an {@code UnsupportedTemporalTypeException}.
633 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
634 * <p>
635 * If the field is not a {@code ChronoField}, then the result of this method
636 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
637 * passing {@code this} as the argument. Whether the value can be obtained,
638 * and what the value represents, is determined by the field.
639 *
640 * @param field the field to get, not null
641 * @return the value for the field
642 * @throws DateTimeException if a value for the field cannot be obtained or
643 * the value is outside the range of valid values for the field
644 * @throws UnsupportedTemporalTypeException if the field is not supported or
645 * the range of values exceeds an {@code int}
646 * @throws ArithmeticException if numeric overflow occurs
647 */
648 @Override // override for Javadoc and performance
649 public int get(TemporalField field) {
650 if (field instanceof ChronoField) {
651 return get0(field);
652 }
653 return ChronoLocalDate.super.get(field);
654 }
655
656 /**
657 * Gets the value of the specified field from this date as a {@code long}.
658 * <p>
659 * This queries this date for the value of the specified field.
660 * If it is not possible to return the value, because the field is not supported
661 * or for some other reason, an exception is thrown.
662 * <p>
663 * If the field is a {@link ChronoField} then the query is implemented here.
664 * The {@link #isSupported(TemporalField) supported fields} will return valid
665 * values based on this date.
666 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
667 * <p>
668 * If the field is not a {@code ChronoField}, then the result of this method
669 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
670 * passing {@code this} as the argument. Whether the value can be obtained,
671 * and what the value represents, is determined by the field.
672 *
673 * @param field the field to get, not null
674 * @return the value for the field
675 * @throws DateTimeException if a value for the field cannot be obtained
676 * @throws UnsupportedTemporalTypeException if the field is not supported
677 * @throws ArithmeticException if numeric overflow occurs
678 */
679 @Override
680 public long getLong(TemporalField field) {
681 if (field instanceof ChronoField) {
682 if (field == EPOCH_DAY) {
683 return toEpochDay();
684 }
685 if (field == PROLEPTIC_MONTH) {
686 return getProlepticMonth();
687 }
688 return get0(field);
689 }
690 return field.getFrom(this);
691 }
692
693 private int get0(TemporalField field) {
694 switch ((ChronoField) field) {
695 case DAY_OF_WEEK: return getDayOfWeek().getValue();
696 case ALIGNED_DAY_OF_WEEK_IN_MONTH: return ((day - 1) % 7) + 1;
697 case ALIGNED_DAY_OF_WEEK_IN_YEAR: return ((getDayOfYear() - 1) % 7) + 1;
698 case DAY_OF_MONTH: return day;
699 case DAY_OF_YEAR: return getDayOfYear();
700 case EPOCH_DAY: throw new UnsupportedTemporalTypeException("Invalid field 'EpochDay' for get() method, use getLong() instead");
701 case ALIGNED_WEEK_OF_MONTH: return ((day - 1) / 7) + 1;
702 case ALIGNED_WEEK_OF_YEAR: return ((getDayOfYear() - 1) / 7) + 1;
703 case MONTH_OF_YEAR: return month;
704 case PROLEPTIC_MONTH: throw new UnsupportedTemporalTypeException("Invalid field 'ProlepticMonth' for get() method, use getLong() instead");
705 case YEAR_OF_ERA: return (year >= 1 ? year : 1 - year);
706 case YEAR: return year;
707 case ERA: return (year >= 1 ? 1 : 0);
708 }
709 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
710 }
711
712 private long getProlepticMonth() {
713 return (year * 12L + month - 1);
714 }
715
716 //-----------------------------------------------------------------------
717 /**
718 * Gets the chronology of this date, which is the ISO calendar system.
719 * <p>
720 * The {@code Chronology} represents the calendar system in use.
721 * The ISO-8601 calendar system is the modern civil calendar system used today
722 * in most of the world. It is equivalent to the proleptic Gregorian calendar
723 * system, in which today's rules for leap years are applied for all time.
724 *
725 * @return the ISO chronology, not null
726 */
727 @Override
728 public IsoChronology getChronology() {
729 return IsoChronology.INSTANCE;
730 }
731
732 /**
733 * Gets the era applicable at this date.
734 * <p>
735 * The official ISO-8601 standard does not define eras, however {@code IsoChronology} does.
736 * It defines two eras, 'CE' from year one onwards and 'BCE' from year zero backwards.
737 * Since dates before the Julian-Gregorian cutover are not in line with history,
738 * the cutover between 'BCE' and 'CE' is also not aligned with the commonly used
739 * eras, often referred to using 'BC' and 'AD'.
740 * <p>
741 * Users of this class should typically ignore this method as it exists primarily
742 * to fulfill the {@link ChronoLocalDate} contract where it is necessary to support
743 * the Japanese calendar system.
744 *
745 * @return the IsoEra applicable at this date, not null
746 */
747 @Override // override for Javadoc
748 public IsoEra getEra() {
749 return (getYear() >= 1 ? IsoEra.CE : IsoEra.BCE);
750 }
751
752 /**
753 * Gets the year field.
754 * <p>
755 * This method returns the primitive {@code int} value for the year.
756 * <p>
757 * The year returned by this method is proleptic as per {@code get(YEAR)}.
758 * To obtain the year-of-era, use {@code get(YEAR_OF_ERA)}.
759 *
760 * @return the year, from MIN_YEAR to MAX_YEAR
761 */
762 public int getYear() {
763 return year;
764 }
765
766 /**
767 * Gets the month-of-year field from 1 to 12.
768 * <p>
769 * This method returns the month as an {@code int} from 1 to 12.
770 * Application code is frequently clearer if the enum {@link Month}
771 * is used by calling {@link #getMonth()}.
772 *
773 * @return the month-of-year, from 1 to 12
774 * @see #getMonth()
775 */
776 public int getMonthValue() {
777 return month;
778 }
779
780 /**
781 * Gets the month-of-year field using the {@code Month} enum.
782 * <p>
783 * This method returns the enum {@link Month} for the month.
784 * This avoids confusion as to what {@code int} values mean.
785 * If you need access to the primitive {@code int} value then the enum
786 * provides the {@link Month#getValue() int value}.
787 *
788 * @return the month-of-year, not null
789 * @see #getMonthValue()
790 */
791 public Month getMonth() {
792 return Month.of(month);
793 }
794
795 /**
796 * Gets the day-of-month field.
797 * <p>
798 * This method returns the primitive {@code int} value for the day-of-month.
799 *
800 * @return the day-of-month, from 1 to 31
801 */
802 public int getDayOfMonth() {
803 return day;
804 }
805
806 /**
807 * Gets the day-of-year field.
808 * <p>
809 * This method returns the primitive {@code int} value for the day-of-year.
810 *
811 * @return the day-of-year, from 1 to 365, or 366 in a leap year
812 */
813 public int getDayOfYear() {
814 return getMonth().firstDayOfYear(isLeapYear()) + day - 1;
815 }
816
817 /**
818 * Gets the day-of-week field, which is an enum {@code DayOfWeek}.
819 * <p>
820 * This method returns the enum {@link DayOfWeek} for the day-of-week.
821 * This avoids confusion as to what {@code int} values mean.
822 * If you need access to the primitive {@code int} value then the enum
823 * provides the {@link DayOfWeek#getValue() int value}.
824 * <p>
825 * Additional information can be obtained from the {@code DayOfWeek}.
826 * This includes textual names of the values.
827 *
828 * @return the day-of-week, not null
829 */
830 public DayOfWeek getDayOfWeek() {
831 int dow0 = Math.floorMod(toEpochDay() + 3, 7);
832 return DayOfWeek.of(dow0 + 1);
833 }
834
835 //-----------------------------------------------------------------------
836 /**
837 * Checks if the year is a leap year, according to the ISO proleptic
838 * calendar system rules.
839 * <p>
840 * This method applies the current rules for leap years across the whole time-line.
841 * In general, a year is a leap year if it is divisible by four without
842 * remainder. However, years divisible by 100, are not leap years, with
843 * the exception of years divisible by 400 which are.
844 * <p>
845 * For example, 1904 is a leap year it is divisible by 4.
846 * 1900 was not a leap year as it is divisible by 100, however 2000 was a
847 * leap year as it is divisible by 400.
848 * <p>
849 * The calculation is proleptic - applying the same rules into the far future and far past.
850 * This is historically inaccurate, but is correct for the ISO-8601 standard.
851 *
852 * @return true if the year is leap, false otherwise
853 */
854 @Override // override for Javadoc and performance
855 public boolean isLeapYear() {
856 return IsoChronology.INSTANCE.isLeapYear(year);
857 }
858
859 /**
860 * Returns the length of the month represented by this date.
861 * <p>
862 * This returns the length of the month in days.
863 * For example, a date in January would return 31.
864 *
865 * @return the length of the month in days
866 */
867 @Override
868 public int lengthOfMonth() {
869 switch (month) {
870 case 2:
871 return (isLeapYear() ? 29 : 28);
872 case 4:
873 case 6:
874 case 9:
875 case 11:
876 return 30;
877 default:
878 return 31;
879 }
880 }
881
882 /**
883 * Returns the length of the year represented by this date.
884 * <p>
885 * This returns the length of the year in days, either 365 or 366.
886 *
887 * @return 366 if the year is leap, 365 otherwise
888 */
889 @Override // override for Javadoc and performance
890 public int lengthOfYear() {
891 return (isLeapYear() ? 366 : 365);
892 }
893
894 //-----------------------------------------------------------------------
895 /**
896 * Returns an adjusted copy of this date.
897 * <p>
898 * This returns a {@code LocalDate}, based on this one, with the date adjusted.
899 * The adjustment takes place using the specified adjuster strategy object.
900 * Read the documentation of the adjuster to understand what adjustment will be made.
901 * <p>
902 * A simple adjuster might simply set the one of the fields, such as the year field.
903 * A more complex adjuster might set the date to the last day of the month.
904 * <p>
905 * A selection of common adjustments is provided in
906 * {@link java.time.temporal.TemporalAdjusters TemporalAdjusters}.
907 * These include finding the "last day of the month" and "next Wednesday".
908 * Key date-time classes also implement the {@code TemporalAdjuster} interface,
909 * such as {@link Month} and {@link java.time.MonthDay MonthDay}.
910 * The adjuster is responsible for handling special cases, such as the varying
911 * lengths of month and leap years.
912 * <p>
913 * For example this code returns a date on the last day of July:
914 * <pre>
915 * import static java.time.Month.*;
916 * import static java.time.temporal.TemporalAdjusters.*;
917 *
918 * result = localDate.with(JULY).with(lastDayOfMonth());
919 * </pre>
920 * <p>
921 * The result of this method is obtained by invoking the
922 * {@link TemporalAdjuster#adjustInto(Temporal)} method on the
923 * specified adjuster passing {@code this} as the argument.
924 * <p>
925 * This instance is immutable and unaffected by this method call.
926 *
927 * @param adjuster the adjuster to use, not null
928 * @return a {@code LocalDate} based on {@code this} with the adjustment made, not null
929 * @throws DateTimeException if the adjustment cannot be made
930 * @throws ArithmeticException if numeric overflow occurs
931 */
932 @Override
933 public LocalDate with(TemporalAdjuster adjuster) {
934 // optimizations
935 if (adjuster instanceof LocalDate) {
936 return (LocalDate) adjuster;
937 }
938 return (LocalDate) adjuster.adjustInto(this);
939 }
940
941 /**
942 * Returns a copy of this date with the specified field set to a new value.
943 * <p>
944 * This returns a {@code LocalDate}, based on this one, with the value
945 * for the specified field changed.
946 * This can be used to change any supported field, such as the year, month or day-of-month.
947 * If it is not possible to set the value, because the field is not supported or for
948 * some other reason, an exception is thrown.
949 * <p>
950 * In some cases, changing the specified field can cause the resulting date to become invalid,
951 * such as changing the month from 31st January to February would make the day-of-month invalid.
952 * In cases like this, the field is responsible for resolving the date. Typically it will choose
953 * the previous valid date, which would be the last valid day of February in this example.
954 * <p>
955 * If the field is a {@link ChronoField} then the adjustment is implemented here.
956 * The supported fields behave as follows:
957 * <ul>
958 * <li>{@code DAY_OF_WEEK} -
959 * Returns a {@code LocalDate} with the specified day-of-week.
960 * The date is adjusted up to 6 days forward or backward within the boundary
961 * of a Monday to Sunday week.
962 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH} -
963 * Returns a {@code LocalDate} with the specified aligned-day-of-week.
964 * The date is adjusted to the specified month-based aligned-day-of-week.
965 * Aligned weeks are counted such that the first week of a given month starts
966 * on the first day of that month.
967 * This may cause the date to be moved up to 6 days into the following month.
968 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR} -
969 * Returns a {@code LocalDate} with the specified aligned-day-of-week.
970 * The date is adjusted to the specified year-based aligned-day-of-week.
971 * Aligned weeks are counted such that the first week of a given year starts
972 * on the first day of that year.
973 * This may cause the date to be moved up to 6 days into the following year.
974 * <li>{@code DAY_OF_MONTH} -
975 * Returns a {@code LocalDate} with the specified day-of-month.
976 * The month and year will be unchanged. If the day-of-month is invalid for the
977 * year and month, then a {@code DateTimeException} is thrown.
978 * <li>{@code DAY_OF_YEAR} -
979 * Returns a {@code LocalDate} with the specified day-of-year.
980 * The year will be unchanged. If the day-of-year is invalid for the
981 * year, then a {@code DateTimeException} is thrown.
982 * <li>{@code EPOCH_DAY} -
983 * Returns a {@code LocalDate} with the specified epoch-day.
984 * This completely replaces the date and is equivalent to {@link #ofEpochDay(long)}.
985 * <li>{@code ALIGNED_WEEK_OF_MONTH} -
986 * Returns a {@code LocalDate} with the specified aligned-week-of-month.
987 * Aligned weeks are counted such that the first week of a given month starts
988 * on the first day of that month.
989 * This adjustment moves the date in whole week chunks to match the specified week.
990 * The result will have the same day-of-week as this date.
991 * This may cause the date to be moved into the following month.
992 * <li>{@code ALIGNED_WEEK_OF_YEAR} -
993 * Returns a {@code LocalDate} with the specified aligned-week-of-year.
994 * Aligned weeks are counted such that the first week of a given year starts
995 * on the first day of that year.
996 * This adjustment moves the date in whole week chunks to match the specified week.
997 * The result will have the same day-of-week as this date.
998 * This may cause the date to be moved into the following year.
999 * <li>{@code MONTH_OF_YEAR} -
1000 * Returns a {@code LocalDate} with the specified month-of-year.
1001 * The year will be unchanged. The day-of-month will also be unchanged,
1002 * unless it would be invalid for the new month and year. In that case, the
1003 * day-of-month is adjusted to the maximum valid value for the new month and year.
1004 * <li>{@code PROLEPTIC_MONTH} -
1005 * Returns a {@code LocalDate} with the specified proleptic-month.
1006 * The day-of-month will be unchanged, unless it would be invalid for the new month
1007 * and year. In that case, the day-of-month is adjusted to the maximum valid value
1008 * for the new month and year.
1009 * <li>{@code YEAR_OF_ERA} -
1010 * Returns a {@code LocalDate} with the specified year-of-era.
1011 * The era and month will be unchanged. The day-of-month will also be unchanged,
1012 * unless it would be invalid for the new month and year. In that case, the
1013 * day-of-month is adjusted to the maximum valid value for the new month and year.
1014 * <li>{@code YEAR} -
1015 * Returns a {@code LocalDate} with the specified year.
1016 * The month will be unchanged. The day-of-month will also be unchanged,
1017 * unless it would be invalid for the new month and year. In that case, the
1018 * day-of-month is adjusted to the maximum valid value for the new month and year.
1019 * <li>{@code ERA} -
1020 * Returns a {@code LocalDate} with the specified era.
1021 * The year-of-era and month will be unchanged. The day-of-month will also be unchanged,
1022 * unless it would be invalid for the new month and year. In that case, the
1023 * day-of-month is adjusted to the maximum valid value for the new month and year.
1024 * </ul>
1025 * <p>
1026 * In all cases, if the new value is outside the valid range of values for the field
1027 * then a {@code DateTimeException} will be thrown.
1028 * <p>
1029 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
1030 * <p>
1031 * If the field is not a {@code ChronoField}, then the result of this method
1032 * is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
1033 * passing {@code this} as the argument. In this case, the field determines
1034 * whether and how to adjust the instant.
1035 * <p>
1036 * This instance is immutable and unaffected by this method call.
1037 *
1038 * @param field the field to set in the result, not null
1039 * @param newValue the new value of the field in the result
1040 * @return a {@code LocalDate} based on {@code this} with the specified field set, not null
1041 * @throws DateTimeException if the field cannot be set
1042 * @throws UnsupportedTemporalTypeException if the field is not supported
1043 * @throws ArithmeticException if numeric overflow occurs
1044 */
1045 @Override
1046 public LocalDate with(TemporalField field, long newValue) {
1047 if (field instanceof ChronoField) {
1048 ChronoField f = (ChronoField) field;
1049 f.checkValidValue(newValue);
1050 switch (f) {
1051 case DAY_OF_WEEK: return plusDays(newValue - getDayOfWeek().getValue());
1052 case ALIGNED_DAY_OF_WEEK_IN_MONTH: return plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_MONTH));
1053 case ALIGNED_DAY_OF_WEEK_IN_YEAR: return plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_YEAR));
1054 case DAY_OF_MONTH: return withDayOfMonth((int) newValue);
1055 case DAY_OF_YEAR: return withDayOfYear((int) newValue);
1056 case EPOCH_DAY: return LocalDate.ofEpochDay(newValue);
1057 case ALIGNED_WEEK_OF_MONTH: return plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_MONTH));
1058 case ALIGNED_WEEK_OF_YEAR: return plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_YEAR));
1059 case MONTH_OF_YEAR: return withMonth((int) newValue);
1060 case PROLEPTIC_MONTH: return plusMonths(newValue - getProlepticMonth());
1061 case YEAR_OF_ERA: return withYear((int) (year >= 1 ? newValue : 1 - newValue));
1062 case YEAR: return withYear((int) newValue);
1063 case ERA: return (getLong(ERA) == newValue ? this : withYear(1 - year));
1064 }
1065 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
1066 }
1067 return field.adjustInto(this, newValue);
1068 }
1069
1070 //-----------------------------------------------------------------------
1071 /**
1072 * Returns a copy of this {@code LocalDate} with the year altered.
1073 * <p>
1074 * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
1075 * <p>
1076 * This instance is immutable and unaffected by this method call.
1077 *
1078 * @param year the year to set in the result, from MIN_YEAR to MAX_YEAR
1079 * @return a {@code LocalDate} based on this date with the requested year, not null
1080 * @throws DateTimeException if the year value is invalid
1081 */
1082 public LocalDate withYear(int year) {
1083 if (this.year == year) {
1084 return this;
1085 }
1086 YEAR.checkValidValue(year);
1087 return resolvePreviousValid(year, month, day);
1088 }
1089
1090 /**
1091 * Returns a copy of this {@code LocalDate} with the month-of-year altered.
1092 * <p>
1093 * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
1094 * <p>
1095 * This instance is immutable and unaffected by this method call.
1096 *
1097 * @param month the month-of-year to set in the result, from 1 (January) to 12 (December)
1098 * @return a {@code LocalDate} based on this date with the requested month, not null
1099 * @throws DateTimeException if the month-of-year value is invalid
1100 */
1101 public LocalDate withMonth(int month) {
1102 if (this.month == month) {
1103 return this;
1104 }
1105 MONTH_OF_YEAR.checkValidValue(month);
1106 return resolvePreviousValid(year, month, day);
1107 }
1108
1109 /**
1110 * Returns a copy of this {@code LocalDate} with the day-of-month altered.
1111 * <p>
1112 * If the resulting date is invalid, an exception is thrown.
1113 * <p>
1114 * This instance is immutable and unaffected by this method call.
1115 *
1116 * @param dayOfMonth the day-of-month to set in the result, from 1 to 28-31
1117 * @return a {@code LocalDate} based on this date with the requested day, not null
1118 * @throws DateTimeException if the day-of-month value is invalid,
1119 * or if the day-of-month is invalid for the month-year
1120 */
1121 public LocalDate withDayOfMonth(int dayOfMonth) {
1122 if (this.day == dayOfMonth) {
1123 return this;
1124 }
1125 return of(year, month, dayOfMonth);
1126 }
1127
1128 /**
1129 * Returns a copy of this {@code LocalDate} with the day-of-year altered.
1130 * <p>
1131 * If the resulting date is invalid, an exception is thrown.
1132 * <p>
1133 * This instance is immutable and unaffected by this method call.
1134 *
1135 * @param dayOfYear the day-of-year to set in the result, from 1 to 365-366
1136 * @return a {@code LocalDate} based on this date with the requested day, not null
1137 * @throws DateTimeException if the day-of-year value is invalid,
1138 * or if the day-of-year is invalid for the year
1139 */
1140 public LocalDate withDayOfYear(int dayOfYear) {
1141 if (this.getDayOfYear() == dayOfYear) {
1142 return this;
1143 }
1144 return ofYearDay(year, dayOfYear);
1145 }
1146
1147 //-----------------------------------------------------------------------
1148 /**
1149 * Returns a copy of this date with the specified amount added.
1150 * <p>
1151 * This returns a {@code LocalDate}, based on this one, with the specified amount added.
1152 * The amount is typically {@link Period} but may be any other type implementing
1153 * the {@link TemporalAmount} interface.
1154 * <p>
1155 * The calculation is delegated to the amount object by calling
1156 * {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
1157 * to implement the addition in any way it wishes, however it typically
1158 * calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
1159 * of the amount implementation to determine if it can be successfully added.
1160 * <p>
1161 * This instance is immutable and unaffected by this method call.
1162 *
1163 * @param amountToAdd the amount to add, not null
1164 * @return a {@code LocalDate} based on this date with the addition made, not null
1165 * @throws DateTimeException if the addition cannot be made
1166 * @throws ArithmeticException if numeric overflow occurs
1167 */
1168 @Override
1169 public LocalDate plus(TemporalAmount amountToAdd) {
1170 if (amountToAdd instanceof Period) {
1171 Period periodToAdd = (Period) amountToAdd;
1172 return plusMonths(periodToAdd.toTotalMonths()).plusDays(periodToAdd.getDays());
1173 }
1174 Objects.requireNonNull(amountToAdd, "amountToAdd");
1175 return (LocalDate) amountToAdd.addTo(this);
1176 }
1177
1178 /**
1179 * Returns a copy of this date with the specified amount added.
1180 * <p>
1181 * This returns a {@code LocalDate}, based on this one, with the amount
1182 * in terms of the unit added. If it is not possible to add the amount, because the
1183 * unit is not supported or for some other reason, an exception is thrown.
1184 * <p>
1185 * In some cases, adding the amount can cause the resulting date to become invalid.
1186 * For example, adding one month to 31st January would result in 31st February.
1187 * In cases like this, the unit is responsible for resolving the date.
1188 * Typically it will choose the previous valid date, which would be the last valid
1189 * day of February in this example.
1190 * <p>
1191 * If the field is a {@link ChronoUnit} then the addition is implemented here.
1192 * The supported fields behave as follows:
1193 * <ul>
1194 * <li>{@code DAYS} -
1195 * Returns a {@code LocalDate} with the specified number of days added.
1196 * This is equivalent to {@link #plusDays(long)}.
1197 * <li>{@code WEEKS} -
1198 * Returns a {@code LocalDate} with the specified number of weeks added.
1199 * This is equivalent to {@link #plusWeeks(long)} and uses a 7 day week.
1200 * <li>{@code MONTHS} -
1201 * Returns a {@code LocalDate} with the specified number of months added.
1202 * This is equivalent to {@link #plusMonths(long)}.
1203 * The day-of-month will be unchanged unless it would be invalid for the new
1204 * month and year. In that case, the day-of-month is adjusted to the maximum
1205 * valid value for the new month and year.
1206 * <li>{@code YEARS} -
1207 * Returns a {@code LocalDate} with the specified number of years added.
1208 * This is equivalent to {@link #plusYears(long)}.
1209 * The day-of-month will be unchanged unless it would be invalid for the new
1210 * month and year. In that case, the day-of-month is adjusted to the maximum
1211 * valid value for the new month and year.
1212 * <li>{@code DECADES} -
1213 * Returns a {@code LocalDate} with the specified number of decades added.
1214 * This is equivalent to calling {@link #plusYears(long)} with the amount
1215 * multiplied by 10.
1216 * The day-of-month will be unchanged unless it would be invalid for the new
1217 * month and year. In that case, the day-of-month is adjusted to the maximum
1218 * valid value for the new month and year.
1219 * <li>{@code CENTURIES} -
1220 * Returns a {@code LocalDate} with the specified number of centuries added.
1221 * This is equivalent to calling {@link #plusYears(long)} with the amount
1222 * multiplied by 100.
1223 * The day-of-month will be unchanged unless it would be invalid for the new
1224 * month and year. In that case, the day-of-month is adjusted to the maximum
1225 * valid value for the new month and year.
1226 * <li>{@code MILLENNIA} -
1227 * Returns a {@code LocalDate} with the specified number of millennia added.
1228 * This is equivalent to calling {@link #plusYears(long)} with the amount
1229 * multiplied by 1,000.
1230 * The day-of-month will be unchanged unless it would be invalid for the new
1231 * month and year. In that case, the day-of-month is adjusted to the maximum
1232 * valid value for the new month and year.
1233 * <li>{@code ERAS} -
1234 * Returns a {@code LocalDate} with the specified number of eras added.
1235 * Only two eras are supported so the amount must be one, zero or minus one.
1236 * If the amount is non-zero then the year is changed such that the year-of-era
1237 * is unchanged.
1238 * The day-of-month will be unchanged unless it would be invalid for the new
1239 * month and year. In that case, the day-of-month is adjusted to the maximum
1240 * valid value for the new month and year.
1241 * </ul>
1242 * <p>
1243 * All other {@code ChronoUnit} instances will throw an {@code UnsupportedTemporalTypeException}.
1244 * <p>
1245 * If the field is not a {@code ChronoUnit}, then the result of this method
1246 * is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
1247 * passing {@code this} as the argument. In this case, the unit determines
1248 * whether and how to perform the addition.
1249 * <p>
1250 * This instance is immutable and unaffected by this method call.
1251 *
1252 * @param amountToAdd the amount of the unit to add to the result, may be negative
1253 * @param unit the unit of the amount to add, not null
1254 * @return a {@code LocalDate} based on this date with the specified amount added, not null
1255 * @throws DateTimeException if the addition cannot be made
1256 * @throws UnsupportedTemporalTypeException if the unit is not supported
1257 * @throws ArithmeticException if numeric overflow occurs
1258 */
1259 @Override
1260 public LocalDate plus(long amountToAdd, TemporalUnit unit) {
1261 if (unit instanceof ChronoUnit) {
1262 ChronoUnit f = (ChronoUnit) unit;
1263 switch (f) {
1264 case DAYS: return plusDays(amountToAdd);
1265 case WEEKS: return plusWeeks(amountToAdd);
1266 case MONTHS: return plusMonths(amountToAdd);
1267 case YEARS: return plusYears(amountToAdd);
1268 case DECADES: return plusYears(Math.multiplyExact(amountToAdd, 10));
1269 case CENTURIES: return plusYears(Math.multiplyExact(amountToAdd, 100));
1270 case MILLENNIA: return plusYears(Math.multiplyExact(amountToAdd, 1000));
1271 case ERAS: return with(ERA, Math.addExact(getLong(ERA), amountToAdd));
1272 }
1273 throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1274 }
1275 return unit.addTo(this, amountToAdd);
1276 }
1277
1278 //-----------------------------------------------------------------------
1279 /**
1280 * Returns a copy of this {@code LocalDate} with the specified number of years added.
1281 * <p>
1282 * This method adds the specified amount to the years field in three steps:
1283 * <ol>
1284 * <li>Add the input years to the year field</li>
1285 * <li>Check if the resulting date would be invalid</li>
1286 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1287 * </ol>
1288 * <p>
1289 * For example, 2008-02-29 (leap year) plus one year would result in the
1290 * invalid date 2009-02-29 (standard year). Instead of returning an invalid
1291 * result, the last valid day of the month, 2009-02-28, is selected instead.
1292 * <p>
1293 * This instance is immutable and unaffected by this method call.
1294 *
1295 * @param yearsToAdd the years to add, may be negative
1296 * @return a {@code LocalDate} based on this date with the years added, not null
1297 * @throws DateTimeException if the result exceeds the supported date range
1298 */
1299 public LocalDate plusYears(long yearsToAdd) {
1300 if (yearsToAdd == 0) {
1301 return this;
1302 }
1303 int newYear = YEAR.checkValidIntValue(year + yearsToAdd); // safe overflow
1304 return resolvePreviousValid(newYear, month, day);
1305 }
1306
1307 /**
1308 * Returns a copy of this {@code LocalDate} with the specified number of months added.
1309 * <p>
1310 * This method adds the specified amount to the months field in three steps:
1311 * <ol>
1312 * <li>Add the input months to the month-of-year field</li>
1313 * <li>Check if the resulting date would be invalid</li>
1314 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1315 * </ol>
1316 * <p>
1317 * For example, 2007-03-31 plus one month would result in the invalid date
1318 * 2007-04-31. Instead of returning an invalid result, the last valid day
1319 * of the month, 2007-04-30, is selected instead.
1320 * <p>
1321 * This instance is immutable and unaffected by this method call.
1322 *
1323 * @param monthsToAdd the months to add, may be negative
1324 * @return a {@code LocalDate} based on this date with the months added, not null
1325 * @throws DateTimeException if the result exceeds the supported date range
1326 */
1327 public LocalDate plusMonths(long monthsToAdd) {
1328 if (monthsToAdd == 0) {
1329 return this;
1330 }
1331 long monthCount = year * 12L + (month - 1);
1332 long calcMonths = monthCount + monthsToAdd; // safe overflow
1333 int newYear = YEAR.checkValidIntValue(Math.floorDiv(calcMonths, 12));
1334 int newMonth = Math.floorMod(calcMonths, 12) + 1;
1335 return resolvePreviousValid(newYear, newMonth, day);
1336 }
1337
1338 /**
1339 * Returns a copy of this {@code LocalDate} with the specified number of weeks added.
1340 * <p>
1341 * This method adds the specified amount in weeks to the days field incrementing
1342 * the 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 week would result in 2009-01-07.
1346 * <p>
1347 * This instance is immutable and unaffected by this method call.
1348 *
1349 * @param weeksToAdd the weeks to add, may be negative
1350 * @return a {@code LocalDate} based on this date with the weeks added, not null
1351 * @throws DateTimeException if the result exceeds the supported date range
1352 */
1353 public LocalDate plusWeeks(long weeksToAdd) {
1354 return plusDays(Math.multiplyExact(weeksToAdd, 7));
1355 }
1356
1357 /**
1358 * Returns a copy of this {@code LocalDate} with the specified number of days added.
1359 * <p>
1360 * This method adds the specified amount to the days field incrementing the
1361 * month and year fields as necessary to ensure the result remains valid.
1362 * The result is only invalid if the maximum/minimum year is exceeded.
1363 * <p>
1364 * For example, 2008-12-31 plus one day would result in 2009-01-01.
1365 * <p>
1366 * This instance is immutable and unaffected by this method call.
1367 *
1368 * @param daysToAdd the days to add, may be negative
1369 * @return a {@code LocalDate} based on this date with the days added, not null
1370 * @throws DateTimeException if the result exceeds the supported date range
1371 */
1372 public LocalDate plusDays(long daysToAdd) {
1373 if (daysToAdd == 0) {
1374 return this;
1375 }
1376 long dom = day + daysToAdd;
1377 if (dom > 0) {
1378 if (dom <= 28) {
1379 return new LocalDate(year, month, (int) dom);
1380 } else if (dom <= 59) { // 59th Jan is 28th Feb, 59th Feb is 31st Mar
1381 long monthLen = lengthOfMonth();
1382 if (dom <= monthLen) {
1383 return new LocalDate(year, month, (int) dom);
1384 } else if (month < 12) {
1385 return new LocalDate(year, month + 1, (int) (dom - monthLen));
1386 } else {
1387 YEAR.checkValidValue(year + 1);
1388 return new LocalDate(year + 1, 1, (int) (dom - monthLen));
1389 }
1390 }
1391 }
1392
1393 long mjDay = Math.addExact(toEpochDay(), daysToAdd);
1394 return LocalDate.ofEpochDay(mjDay);
1395 }
1396
1397 //-----------------------------------------------------------------------
1398 /**
1399 * Returns a copy of this date with the specified amount subtracted.
1400 * <p>
1401 * This returns a {@code LocalDate}, based on this one, with the specified amount subtracted.
1402 * The amount is typically {@link Period} but may be any other type implementing
1403 * the {@link TemporalAmount} interface.
1404 * <p>
1405 * The calculation is delegated to the amount object by calling
1406 * {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
1407 * to implement the subtraction in any way it wishes, however it typically
1408 * calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
1409 * of the amount implementation to determine if it can be successfully subtracted.
1410 * <p>
1411 * This instance is immutable and unaffected by this method call.
1412 *
1413 * @param amountToSubtract the amount to subtract, not null
1414 * @return a {@code LocalDate} based on this date with the subtraction made, not null
1415 * @throws DateTimeException if the subtraction cannot be made
1416 * @throws ArithmeticException if numeric overflow occurs
1417 */
1418 @Override
1419 public LocalDate minus(TemporalAmount amountToSubtract) {
1420 if (amountToSubtract instanceof Period) {
1421 Period periodToSubtract = (Period) amountToSubtract;
1422 return minusMonths(periodToSubtract.toTotalMonths()).minusDays(periodToSubtract.getDays());
1423 }
1424 Objects.requireNonNull(amountToSubtract, "amountToSubtract");
1425 return (LocalDate) amountToSubtract.subtractFrom(this);
1426 }
1427
1428 /**
1429 * Returns a copy of this date with the specified amount subtracted.
1430 * <p>
1431 * This returns a {@code LocalDate}, based on this one, with the amount
1432 * in terms of the unit subtracted. If it is not possible to subtract the amount,
1433 * because the unit is not supported or for some other reason, an exception is thrown.
1434 * <p>
1435 * This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
1436 * See that method for a full description of how addition, and thus subtraction, works.
1437 * <p>
1438 * This instance is immutable and unaffected by this method call.
1439 *
1440 * @param amountToSubtract the amount of the unit to subtract from the result, may be negative
1441 * @param unit the unit of the amount to subtract, not null
1442 * @return a {@code LocalDate} based on this date with the specified amount subtracted, not null
1443 * @throws DateTimeException if the subtraction cannot be made
1444 * @throws UnsupportedTemporalTypeException if the unit is not supported
1445 * @throws ArithmeticException if numeric overflow occurs
1446 */
1447 @Override
1448 public LocalDate minus(long amountToSubtract, TemporalUnit unit) {
1449 return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
1450 }
1451
1452 //-----------------------------------------------------------------------
1453 /**
1454 * Returns a copy of this {@code LocalDate} with the specified number of years subtracted.
1455 * <p>
1456 * This method subtracts the specified amount from the years field in three steps:
1457 * <ol>
1458 * <li>Subtract the input years from the year field</li>
1459 * <li>Check if the resulting date would be invalid</li>
1460 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1461 * </ol>
1462 * <p>
1463 * For example, 2008-02-29 (leap year) minus one year would result in the
1464 * invalid date 2007-02-29 (standard year). Instead of returning an invalid
1465 * result, the last valid day of the month, 2007-02-28, is selected instead.
1466 * <p>
1467 * This instance is immutable and unaffected by this method call.
1468 *
1469 * @param yearsToSubtract the years to subtract, may be negative
1470 * @return a {@code LocalDate} based on this date with the years subtracted, not null
1471 * @throws DateTimeException if the result exceeds the supported date range
1472 */
1473 public LocalDate minusYears(long yearsToSubtract) {
1474 return (yearsToSubtract == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-yearsToSubtract));
1475 }
1476
1477 /**
1478 * Returns a copy of this {@code LocalDate} with the specified number of months subtracted.
1479 * <p>
1480 * This method subtracts the specified amount from the months field in three steps:
1481 * <ol>
1482 * <li>Subtract the input months from the month-of-year field</li>
1483 * <li>Check if the resulting date would be invalid</li>
1484 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1485 * </ol>
1486 * <p>
1487 * For example, 2007-03-31 minus one month would result in the invalid date
1488 * 2007-02-31. Instead of returning an invalid result, the last valid day
1489 * of the month, 2007-02-28, is selected instead.
1490 * <p>
1491 * This instance is immutable and unaffected by this method call.
1492 *
1493 * @param monthsToSubtract the months to subtract, may be negative
1494 * @return a {@code LocalDate} based on this date with the months subtracted, not null
1495 * @throws DateTimeException if the result exceeds the supported date range
1496 */
1497 public LocalDate minusMonths(long monthsToSubtract) {
1498 return (monthsToSubtract == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-monthsToSubtract));
1499 }
1500
1501 /**
1502 * Returns a copy of this {@code LocalDate} with the specified number of weeks subtracted.
1503 * <p>
1504 * This method subtracts the specified amount in weeks from the days field decrementing
1505 * the month and year fields as necessary to ensure the result remains valid.
1506 * The result is only invalid if the maximum/minimum year is exceeded.
1507 * <p>
1508 * For example, 2009-01-07 minus one week would result in 2008-12-31.
1509 * <p>
1510 * This instance is immutable and unaffected by this method call.
1511 *
1512 * @param weeksToSubtract the weeks to subtract, may be negative
1513 * @return a {@code LocalDate} based on this date with the weeks subtracted, not null
1514 * @throws DateTimeException if the result exceeds the supported date range
1515 */
1516 public LocalDate minusWeeks(long weeksToSubtract) {
1517 return (weeksToSubtract == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeksToSubtract));
1518 }
1519
1520 /**
1521 * Returns a copy of this {@code LocalDate} with the specified number of days subtracted.
1522 * <p>
1523 * This method subtracts the specified amount from the days field decrementing the
1524 * month and year fields as necessary to ensure the result remains valid.
1525 * The result is only invalid if the maximum/minimum year is exceeded.
1526 * <p>
1527 * For example, 2009-01-01 minus one day would result in 2008-12-31.
1528 * <p>
1529 * This instance is immutable and unaffected by this method call.
1530 *
1531 * @param daysToSubtract the days to subtract, may be negative
1532 * @return a {@code LocalDate} based on this date with the days subtracted, not null
1533 * @throws DateTimeException if the result exceeds the supported date range
1534 */
1535 public LocalDate minusDays(long daysToSubtract) {
1536 return (daysToSubtract == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-daysToSubtract));
1537 }
1538
1539 //-----------------------------------------------------------------------
1540 /**
1541 * Queries this date using the specified query.
1542 * <p>
1543 * This queries this date using the specified query strategy object.
1544 * The {@code TemporalQuery} object defines the logic to be used to
1545 * obtain the result. Read the documentation of the query to understand
1546 * what the result of this method will be.
1547 * <p>
1548 * The result of this method is obtained by invoking the
1549 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
1550 * specified query passing {@code this} as the argument.
1551 *
1552 * @param <R> the type of the result
1553 * @param query the query to invoke, not null
1554 * @return the query result, null may be returned (defined by the query)
1555 * @throws DateTimeException if unable to query (defined by the query)
1556 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
1557 */
1558 @SuppressWarnings("unchecked")
1559 @Override
1560 public <R> R query(TemporalQuery<R> query) {
1561 if (query == TemporalQueries.localDate()) {
1562 return (R) this;
1563 }
1564 return ChronoLocalDate.super.query(query);
1565 }
1566
1567 /**
1568 * Adjusts the specified temporal object to have the same date as this object.
1569 * <p>
1570 * This returns a temporal object of the same observable type as the input
1571 * with the date changed to be the same as this.
1572 * <p>
1573 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
1574 * passing {@link ChronoField#EPOCH_DAY} as the field.
1575 * <p>
1576 * In most cases, it is clearer to reverse the calling pattern by using
1577 * {@link Temporal#with(TemporalAdjuster)}:
1578 * <pre>
1579 * // these two lines are equivalent, but the second approach is recommended
1580 * temporal = thisLocalDate.adjustInto(temporal);
1581 * temporal = temporal.with(thisLocalDate);
1582 * </pre>
1583 * <p>
1584 * This instance is immutable and unaffected by this method call.
1585 *
1586 * @param temporal the target object to be adjusted, not null
1587 * @return the adjusted object, not null
1588 * @throws DateTimeException if unable to make the adjustment
1589 * @throws ArithmeticException if numeric overflow occurs
1590 */
1591 @Override // override for Javadoc
1592 public Temporal adjustInto(Temporal temporal) {
1593 return ChronoLocalDate.super.adjustInto(temporal);
1594 }
1595
1596 /**
1597 * Calculates the amount of time until another date in terms of the specified unit.
1598 * <p>
1599 * This calculates the amount of time between two {@code LocalDate}
1600 * objects in terms of a single {@code TemporalUnit}.
1601 * The start and end points are {@code this} and the specified date.
1602 * The result will be negative if the end is before the start.
1603 * The {@code Temporal} passed to this method is converted to a
1604 * {@code LocalDate} using {@link #from(TemporalAccessor)}.
1605 * For example, the amount in days between two dates can be calculated
1606 * using {@code startDate.until(endDate, DAYS)}.
1607 * <p>
1608 * The calculation returns a whole number, representing the number of
1609 * complete units between the two dates.
1610 * For example, the amount in months between 2012-06-15 and 2012-08-14
1611 * will only be one month as it is one day short of two months.
1612 * <p>
1613 * There are two equivalent ways of using this method.
1614 * The first is to invoke this method.
1615 * The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
1616 * <pre>
1617 * // these two lines are equivalent
1618 * amount = start.until(end, MONTHS);
1619 * amount = MONTHS.between(start, end);
1620 * </pre>
1621 * The choice should be made based on which makes the code more readable.
1622 * <p>
1623 * The calculation is implemented in this method for {@link ChronoUnit}.
1624 * The units {@code DAYS}, {@code WEEKS}, {@code MONTHS}, {@code YEARS},
1625 * {@code DECADES}, {@code CENTURIES}, {@code MILLENNIA} and {@code ERAS}
1626 * are supported. Other {@code ChronoUnit} values will throw an exception.
1627 * <p>
1628 * If the unit is not a {@code ChronoUnit}, then the result of this method
1629 * is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
1630 * passing {@code this} as the first argument and the converted input temporal
1631 * as the second argument.
1632 * <p>
1633 * This instance is immutable and unaffected by this method call.
1634 *
1635 * @param endExclusive the end date, exclusive, which is converted to a {@code LocalDate}, not null
1636 * @param unit the unit to measure the amount in, not null
1637 * @return the amount of time between this date and the end date
1638 * @throws DateTimeException if the amount cannot be calculated, or the end
1639 * temporal cannot be converted to a {@code LocalDate}
1640 * @throws UnsupportedTemporalTypeException if the unit is not supported
1641 * @throws ArithmeticException if numeric overflow occurs
1642 */
1643 @Override
1644 public long until(Temporal endExclusive, TemporalUnit unit) {
1645 LocalDate end = LocalDate.from(endExclusive);
1646 if (unit instanceof ChronoUnit) {
1647 switch ((ChronoUnit) unit) {
1648 case DAYS: return daysUntil(end);
1649 case WEEKS: return daysUntil(end) / 7;
1650 case MONTHS: return monthsUntil(end);
1651 case YEARS: return monthsUntil(end) / 12;
1652 case DECADES: return monthsUntil(end) / 120;
1653 case CENTURIES: return monthsUntil(end) / 1200;
1654 case MILLENNIA: return monthsUntil(end) / 12000;
1655 case ERAS: return end.getLong(ERA) - getLong(ERA);
1656 }
1657 throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1658 }
1659 return unit.between(this, end);
1660 }
1661
1662 long daysUntil(LocalDate end) {
1663 return end.toEpochDay() - toEpochDay(); // no overflow
1664 }
1665
1666 private long monthsUntil(LocalDate end) {
1667 long packed1 = getProlepticMonth() * 32L + getDayOfMonth(); // no overflow
1668 long packed2 = end.getProlepticMonth() * 32L + end.getDayOfMonth(); // no overflow
1669 return (packed2 - packed1) / 32;
1670 }
1671
1672 /**
1673 * Calculates the period between this date and another date as a {@code Period}.
1674 * <p>
1675 * This calculates the period between two dates in terms of years, months and days.
1676 * The start and end points are {@code this} and the specified date.
1677 * The result will be negative if the end is before the start.
1678 * The negative sign will be the same in each of year, month and day.
1679 * <p>
1680 * The calculation is performed using the ISO calendar system.
1681 * If necessary, the input date will be converted to ISO.
1682 * <p>
1683 * The start date is included, but the end date is not.
1684 * The period is calculated by removing complete months, then calculating
1685 * the remaining number of days, adjusting to ensure that both have the same sign.
1686 * The number of months is then normalized into years and months based on a 12 month year.
1687 * A month is considered to be complete if the end day-of-month is greater
1688 * than or equal to the start day-of-month.
1689 * For example, from {@code 2010-01-15} to {@code 2011-03-18} is "1 year, 2 months and 3 days".
1690 * <p>
1691 * There are two equivalent ways of using this method.
1692 * The first is to invoke this method.
1693 * The second is to use {@link Period#between(LocalDate, LocalDate)}:
1694 * <pre>
1695 * // these two lines are equivalent
1696 * period = start.until(end);
1697 * period = Period.between(start, end);
1698 * </pre>
1699 * The choice should be made based on which makes the code more readable.
1700 *
1701 * @param endDateExclusive the end date, exclusive, which may be in any chronology, not null
1702 * @return the period between this date and the end date, not null
1703 */
1704 @Override
1705 public Period until(ChronoLocalDate endDateExclusive) {
1706 LocalDate end = LocalDate.from(endDateExclusive);
1707 long totalMonths = end.getProlepticMonth() - this.getProlepticMonth(); // safe
1708 int days = end.day - this.day;
1709 if (totalMonths > 0 && days < 0) {
1710 totalMonths--;
1711 LocalDate calcDate = this.plusMonths(totalMonths);
1712 days = (int) (end.toEpochDay() - calcDate.toEpochDay()); // safe
1713 } else if (totalMonths < 0 && days > 0) {
1714 totalMonths++;
1715 days -= end.lengthOfMonth();
1716 }
1717 long years = totalMonths / 12; // safe
1718 int months = (int) (totalMonths % 12); // safe
1719 return Period.of(Math.toIntExact(years), months, days);
1720 }
1721
1722 /**
1723 * Returns a sequential ordered stream of dates. The returned stream starts from this date
1724 * (inclusive) and goes to {@code endExclusive} (exclusive) by an incremental step of 1 day.
1725 * <p>
1726 * This method is equivalent to {@code datesUntil(endExclusive, Period.ofDays(1))}.
1727 *
1728 * @param endExclusive the end date, exclusive, not null
1729 * @return a sequential {@code Stream} for the range of {@code LocalDate} values
1730 * @throws IllegalArgumentException if end date is before this date
1731 * @since 9
1732 */
1733 public Stream<LocalDate> datesUntil(LocalDate endExclusive) {
1734 long end = endExclusive.toEpochDay();
1735 long start = toEpochDay();
1736 if (end < start) {
1737 throw new IllegalArgumentException(endExclusive + " < " + this);
1738 }
1739 return LongStream.range(start, end).mapToObj(LocalDate::ofEpochDay);
1740 }
1741
1742 /**
1743 * Returns a sequential ordered stream of dates by given incremental step. The returned stream
1744 * starts from this date (inclusive) and goes to {@code endExclusive} (exclusive).
1745 * <p>
1746 * The n-th date which appears in the stream is equal to {@code this.plus(step.multipliedBy(n))}
1747 * (but the result of step multiplication never overflows). For example, if this date is
1748 * {@code 2015-01-31}, the end date is {@code 2015-05-01} and the step is 1 month, then the
1749 * stream contains {@code 2015-01-31}, {@code 2015-02-28}, {@code 2015-03-31}, and
1750 * {@code 2015-04-30}.
1751 *
1752 * @param endExclusive the end date, exclusive, not null
1753 * @param step the non-zero, non-negative {@code Period} which represents the step.
1754 * @return a sequential {@code Stream} for the range of {@code LocalDate} values
1755 * @throws IllegalArgumentException if step is zero, or {@code step.getDays()} and
1756 * {@code step.toTotalMonths()} have opposite sign, or end date is before this date
1757 * and step is positive, or end date is after this date and step is negative
1758 * @since 9
1759 */
1760 public Stream<LocalDate> datesUntil(LocalDate endExclusive, Period step) {
1761 if (step.isZero()) {
1762 throw new IllegalArgumentException("step is zero");
1763 }
1764 long end = endExclusive.toEpochDay();
1765 long start = toEpochDay();
1766 long until = end - start;
1767 long months = step.toTotalMonths();
1768 long days = step.getDays();
1769 if ((months < 0 && days > 0) || (months > 0 && days < 0)) {
1770 throw new IllegalArgumentException("period months and days are of opposite sign");
1771 }
1772 if (until == 0) {
1773 return Stream.empty();
1774 }
1775 int sign = months > 0 || days > 0 ? 1 : -1;
1776 if (sign < 0 ^ until < 0) {
1777 throw new IllegalArgumentException(endExclusive + (sign < 0 ? " > " : " < ") + this);
1778 }
1779 if (months == 0) {
1780 long steps = (until - sign) / days; // non-negative
1781 return LongStream.rangeClosed(0, steps).mapToObj(
1782 n -> LocalDate.ofEpochDay(start + n * days));
1783 }
1784 // 48699/1600 = 365.2425/12, no overflow, non-negative result
1785 long steps = until * 1600 / (months * 48699 + days * 1600) + 1;
1786 long addMonths = months * steps;
1787 long addDays = days * steps;
1788 long maxAddMonths = months > 0 ? MAX.getProlepticMonth() - getProlepticMonth()
1789 : getProlepticMonth() - MIN.getProlepticMonth();
1790 // adjust steps estimation
1791 if (addMonths * sign > maxAddMonths
1792 || (plusMonths(addMonths).toEpochDay() + addDays) * sign >= end * sign) {
1793 steps--;
1794 addMonths -= months;
1795 addDays -= days;
1796 if (addMonths * sign > maxAddMonths
1797 || (plusMonths(addMonths).toEpochDay() + addDays) * sign >= end * sign) {
1798 steps--;
1799 }
1800 }
1801 return LongStream.rangeClosed(0, steps).mapToObj(
1802 n -> this.plusMonths(months * n).plusDays(days * n));
1803 }
1804
1805 /**
1806 * Formats this date using the specified formatter.
1807 * <p>
1808 * This date will be passed to the formatter to produce a string.
1809 *
1810 * @param formatter the formatter to use, not null
1811 * @return the formatted date string, not null
1812 * @throws DateTimeException if an error occurs during printing
1813 */
1814 @Override // override for Javadoc and performance
1815 public String format(DateTimeFormatter formatter) {
1816 Objects.requireNonNull(formatter, "formatter");
1817 return formatter.format(this);
1818 }
1819
1820 //-----------------------------------------------------------------------
1821 /**
1822 * Combines this date with a time to create a {@code LocalDateTime}.
1823 * <p>
1824 * This returns a {@code LocalDateTime} formed from this date at the specified time.
1825 * All possible combinations of date and time are valid.
1826 *
1827 * @param time the time to combine with, not null
1828 * @return the local date-time formed from this date and the specified time, not null
1829 */
1830 @Override
1831 public LocalDateTime atTime(LocalTime time) {
1832 return LocalDateTime.of(this, time);
1833 }
1834
1835 /**
1836 * Combines this date with a time to create a {@code LocalDateTime}.
1837 * <p>
1838 * This returns a {@code LocalDateTime} formed from this date at the
1839 * specified hour and minute.
1840 * The seconds and nanosecond fields will be set to zero.
1841 * The individual time fields must be within their valid range.
1842 * All possible combinations of date and time are valid.
1843 *
1844 * @param hour the hour-of-day to use, from 0 to 23
1845 * @param minute the minute-of-hour to use, from 0 to 59
1846 * @return the local date-time formed from this date and the specified time, not null
1847 * @throws DateTimeException if the value of any field is out of range
1848 */
1849 public LocalDateTime atTime(int hour, int minute) {
1850 return atTime(LocalTime.of(hour, minute));
1851 }
1852
1853 /**
1854 * Combines this date with a time to create a {@code LocalDateTime}.
1855 * <p>
1856 * This returns a {@code LocalDateTime} formed from this date at the
1857 * specified hour, minute and second.
1858 * The nanosecond field will be set to zero.
1859 * The individual time fields must be within their valid range.
1860 * All possible combinations of date and time are valid.
1861 *
1862 * @param hour the hour-of-day to use, from 0 to 23
1863 * @param minute the minute-of-hour to use, from 0 to 59
1864 * @param second the second-of-minute to represent, from 0 to 59
1865 * @return the local date-time formed from this date and the specified time, not null
1866 * @throws DateTimeException if the value of any field is out of range
1867 */
1868 public LocalDateTime atTime(int hour, int minute, int second) {
1869 return atTime(LocalTime.of(hour, minute, second));
1870 }
1871
1872 /**
1873 * Combines this date with a time to create a {@code LocalDateTime}.
1874 * <p>
1875 * This returns a {@code LocalDateTime} formed from this date at the
1876 * specified hour, minute, second and nanosecond.
1877 * The individual time fields must be within their valid range.
1878 * All possible combinations of date and time are valid.
1879 *
1880 * @param hour the hour-of-day to use, from 0 to 23
1881 * @param minute the minute-of-hour to use, from 0 to 59
1882 * @param second the second-of-minute to represent, from 0 to 59
1883 * @param nanoOfSecond the nano-of-second to represent, from 0 to 999,999,999
1884 * @return the local date-time formed from this date and the specified time, not null
1885 * @throws DateTimeException if the value of any field is out of range
1886 */
1887 public LocalDateTime atTime(int hour, int minute, int second, int nanoOfSecond) {
1888 return atTime(LocalTime.of(hour, minute, second, nanoOfSecond));
1889 }
1890
1891 /**
1892 * Combines this date with an offset time to create an {@code OffsetDateTime}.
1893 * <p>
1894 * This returns an {@code OffsetDateTime} formed from this date at the specified time.
1895 * All possible combinations of date and time are valid.
1896 *
1897 * @param time the time to combine with, not null
1898 * @return the offset date-time formed from this date and the specified time, not null
1899 */
1900 public OffsetDateTime atTime(OffsetTime time) {
1901 return OffsetDateTime.of(LocalDateTime.of(this, time.toLocalTime()), time.getOffset());
1902 }
1903
1904 /**
1905 * Combines this date with the time of midnight to create a {@code LocalDateTime}
1906 * at the start of this date.
1907 * <p>
1908 * This returns a {@code LocalDateTime} formed from this date at the time of
1909 * midnight, 00:00, at the start of this date.
1910 *
1911 * @return the local date-time of midnight at the start of this date, not null
1912 */
1913 public LocalDateTime atStartOfDay() {
1914 return LocalDateTime.of(this, LocalTime.MIDNIGHT);
1915 }
1916
1917 /**
1918 * Returns a zoned date-time from this date at the earliest valid time according
1919 * to the rules in the time-zone.
1920 * <p>
1921 * Time-zone rules, such as daylight savings, mean that not every local date-time
1922 * is valid for the specified zone, thus the local date-time may not be midnight.
1923 * <p>
1924 * In most cases, there is only one valid offset for a local date-time.
1925 * In the case of an overlap, there are two valid offsets, and the earlier one is used,
1926 * corresponding to the first occurrence of midnight on the date.
1927 * In the case of a gap, the zoned date-time will represent the instant just after the gap.
1928 * <p>
1929 * If the zone ID is a {@link ZoneOffset}, then the result always has a time of midnight.
1930 * <p>
1931 * To convert to a specific time in a given time-zone call {@link #atTime(LocalTime)}
1932 * followed by {@link LocalDateTime#atZone(ZoneId)}.
1933 *
1934 * @param zone the zone ID to use, not null
1935 * @return the zoned date-time formed from this date and the earliest valid time for the zone, not null
1936 */
1937 public ZonedDateTime atStartOfDay(ZoneId zone) {
1938 Objects.requireNonNull(zone, "zone");
1939 // need to handle case where there is a gap from 11:30 to 00:30
1940 // standard ZDT factory would result in 01:00 rather than 00:30
1941 LocalDateTime ldt = atTime(LocalTime.MIDNIGHT);
1942 if (zone instanceof ZoneOffset == false) {
1943 ZoneRules rules = zone.getRules();
1944 ZoneOffsetTransition trans = rules.getTransition(ldt);
1945 if (trans != null && trans.isGap()) {
1946 ldt = trans.getDateTimeAfter();
1947 }
1948 }
1949 return ZonedDateTime.of(ldt, zone);
1950 }
1951
1952 //-----------------------------------------------------------------------
1953 @Override
1954 public long toEpochDay() {
1955 long y = year;
1956 long m = month;
1957 long total = 0;
1958 total += 365 * y;
1959 if (y >= 0) {
1960 total += (y + 3) / 4 - (y + 99) / 100 + (y + 399) / 400;
1961 } else {
1962 total -= y / -4 - y / -100 + y / -400;
1963 }
1964 total += ((367 * m - 362) / 12);
1965 total += day - 1;
1966 if (m > 2) {
1967 total--;
1968 if (isLeapYear() == false) {
1969 total--;
1970 }
1971 }
1972 return total - DAYS_0000_TO_1970;
1973 }
1974
1975 /**
1976 * Converts this {@code LocalDate} to the number of seconds since the epoch
1977 * of 1970-01-01T00:00:00Z.
1978 * <p>
1979 * This combines this local date with the specified time and
1980 * offset to calculate the epoch-second value, which is the
1981 * number of elapsed seconds from 1970-01-01T00:00:00Z.
1982 * Instants on the time-line after the epoch are positive, earlier
1983 * are negative.
1984 *
1985 * @param time the local time, not null
1986 * @param offset the zone offset, not null
1987 * @return the number of seconds since the epoch of 1970-01-01T00:00:00Z, may be negative
1988 * @since 9
1989 */
1990 public long toEpochSecond(LocalTime time, ZoneOffset offset) {
1991 Objects.requireNonNull(time, "time");
1992 Objects.requireNonNull(offset, "offset");
1993 long secs = toEpochDay() * SECONDS_PER_DAY + time.toSecondOfDay();
1994 secs -= offset.getTotalSeconds();
1995 return secs;
1996 }
1997
1998 //-----------------------------------------------------------------------
1999 /**
2000 * Compares this date to another date.
2001 * <p>
2002 * The comparison is primarily based on the date, from earliest to latest.
2003 * It is "consistent with equals", as defined by {@link Comparable}.
2004 * <p>
2005 * If all the dates being compared are instances of {@code LocalDate},
2006 * then the comparison will be entirely based on the date.
2007 * If some dates being compared are in different chronologies, then the
2008 * chronology is also considered, see {@link java.time.chrono.ChronoLocalDate#compareTo}.
2009 *
2010 * @param other the other date to compare to, not null
2011 * @return the comparator value, negative if less, positive if greater
2012 */
2013 @Override // override for Javadoc and performance
2014 public int compareTo(ChronoLocalDate other) {
2015 if (other instanceof LocalDate) {
2016 return compareTo0((LocalDate) other);
2017 }
2018 return ChronoLocalDate.super.compareTo(other);
2019 }
2020
2021 int compareTo0(LocalDate otherDate) {
2022 int cmp = (year - otherDate.year);
2023 if (cmp == 0) {
2024 cmp = (month - otherDate.month);
2025 if (cmp == 0) {
2026 cmp = (day - otherDate.day);
2027 }
2028 }
2029 return cmp;
2030 }
2031
2032 /**
2033 * Checks if this date is after the specified date.
2034 * <p>
2035 * This checks to see if this date represents a point on the
2036 * local time-line after the other date.
2037 * <pre>
2038 * LocalDate a = LocalDate.of(2012, 6, 30);
2039 * LocalDate b = LocalDate.of(2012, 7, 1);
2040 * a.isAfter(b) == false
2041 * a.isAfter(a) == false
2042 * b.isAfter(a) == true
2043 * </pre>
2044 * <p>
2045 * This method only considers the position of the two dates on the local time-line.
2046 * It does not take into account the chronology, or calendar system.
2047 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)},
2048 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2049 *
2050 * @param other the other date to compare to, not null
2051 * @return true if this date is after the specified date
2052 */
2053 @Override // override for Javadoc and performance
2054 public boolean isAfter(ChronoLocalDate other) {
2055 if (other instanceof LocalDate) {
2056 return compareTo0((LocalDate) other) > 0;
2057 }
2058 return ChronoLocalDate.super.isAfter(other);
2059 }
2060
2061 /**
2062 * Checks if this date is before the specified date.
2063 * <p>
2064 * This checks to see if this date represents a point on the
2065 * local time-line before the other date.
2066 * <pre>
2067 * LocalDate a = LocalDate.of(2012, 6, 30);
2068 * LocalDate b = LocalDate.of(2012, 7, 1);
2069 * a.isBefore(b) == true
2070 * a.isBefore(a) == false
2071 * b.isBefore(a) == false
2072 * </pre>
2073 * <p>
2074 * This method only considers the position of the two dates on the local time-line.
2075 * It does not take into account the chronology, or calendar system.
2076 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)},
2077 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2078 *
2079 * @param other the other date to compare to, not null
2080 * @return true if this date is before the specified date
2081 */
2082 @Override // override for Javadoc and performance
2083 public boolean isBefore(ChronoLocalDate other) {
2084 if (other instanceof LocalDate) {
2085 return compareTo0((LocalDate) other) < 0;
2086 }
2087 return ChronoLocalDate.super.isBefore(other);
2088 }
2089
2090 /**
2091 * Checks if this date is equal to the specified date.
2092 * <p>
2093 * This checks to see if this date represents the same point on the
2094 * local time-line as the other date.
2095 * <pre>
2096 * LocalDate a = LocalDate.of(2012, 6, 30);
2097 * LocalDate b = LocalDate.of(2012, 7, 1);
2098 * a.isEqual(b) == false
2099 * a.isEqual(a) == true
2100 * b.isEqual(a) == false
2101 * </pre>
2102 * <p>
2103 * This method only considers the position of the two dates on the local time-line.
2104 * It does not take into account the chronology, or calendar system.
2105 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)}
2106 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2107 *
2108 * @param other the other date to compare to, not null
2109 * @return true if this date is equal to the specified date
2110 */
2111 @Override // override for Javadoc and performance
2112 public boolean isEqual(ChronoLocalDate other) {
2113 if (other instanceof LocalDate) {
2114 return compareTo0((LocalDate) other) == 0;
2115 }
2116 return ChronoLocalDate.super.isEqual(other);
2117 }
2118
2119 //-----------------------------------------------------------------------
2120 /**
2121 * Checks if this date is equal to another date.
2122 * <p>
2123 * Compares this {@code LocalDate} with another ensuring that the date is the same.
2124 * <p>
2125 * Only objects of type {@code LocalDate} are compared, other types return false.
2126 * To compare the dates of two {@code TemporalAccessor} instances, including dates
2127 * in two different chronologies, use {@link ChronoField#EPOCH_DAY} as a comparator.
2128 *
2129 * @param obj the object to check, null returns false
2130 * @return true if this is equal to the other date
2131 */
2132 @Override
2133 public boolean equals(Object obj) {
2134 if (this == obj) {
2135 return true;
2136 }
2137 if (obj instanceof LocalDate) {
2138 return compareTo0((LocalDate) obj) == 0;
2139 }
2140 return false;
2141 }
2142
2143 /**
2144 * A hash code for this date.
2145 *
2146 * @return a suitable hash code
2147 */
2148 @Override
2149 public int hashCode() {
2150 int yearValue = year;
2151 int monthValue = month;
2152 int dayValue = day;
2153 return (yearValue & 0xFFFFF800) ^ ((yearValue << 11) + (monthValue << 6) + (dayValue));
2154 }
2155
2156 //-----------------------------------------------------------------------
2157 /**
2158 * Outputs this date as a {@code String}, such as {@code 2007-12-03}.
2159 * <p>
2160 * The output will be in the ISO-8601 format {@code uuuu-MM-dd}.
2161 *
2162 * @return a string representation of this date, not null
2163 */
2164 @Override
2165 public String toString() {
2166 int yearValue = year;
2167 int monthValue = month;
2168 int dayValue = day;
2169 int absYear = Math.abs(yearValue);
2170 StringBuilder buf = new StringBuilder(10);
2171 if (absYear < 1000) {
2172 if (yearValue < 0) {
2173 buf.append(yearValue - 10000).deleteCharAt(1);
2174 } else {
2175 buf.append(yearValue + 10000).deleteCharAt(0);
2176 }
2177 } else {
2178 if (yearValue > 9999) {
2179 buf.append('+');
2180 }
2181 buf.append(yearValue);
2182 }
2183 return buf.append(monthValue < 10 ? "-0" : "-")
2184 .append(monthValue)
2185 .append(dayValue < 10 ? "-0" : "-")
2186 .append(dayValue)
2187 .toString();
2188 }
2189
2190 //-----------------------------------------------------------------------
2191 /**
2192 * Writes the object using a
2193 * <a href="{@docRoot}/serialized-form.html#java.time.Ser">dedicated serialized form</a>.
2194 * @serialData
2195 * <pre>
2196 * out.writeByte(3); // identifies a LocalDate
2197 * out.writeInt(year);
2198 * out.writeByte(month);
2199 * out.writeByte(day);
2200 * </pre>
2201 *
2202 * @return the instance of {@code Ser}, not null
2203 */
2204 @java.io.Serial
2205 private Object writeReplace() {
2206 return new Ser(Ser.LOCAL_DATE_TYPE, this);
2207 }
2208
2209 /**
2210 * Defend against malicious streams.
2211 *
2212 * @param s the stream to read
2213 * @throws InvalidObjectException always
2214 */
2215 @java.io.Serial
2216 private void readObject(ObjectInputStream s) throws InvalidObjectException {
2217 throw new InvalidObjectException("Deserialization via serialization delegate");
2218 }
2219
2220 void writeExternal(DataOutput out) throws IOException {
2221 out.writeInt(year);
2222 out.writeByte(month);
2223 out.writeByte(day);
2224 }
2225
2226 static LocalDate readExternal(DataInput in) throws IOException {
2227 int year = in.readInt();
2228 int month = in.readByte();
2229 int dayOfMonth = in.readByte();
2230 return LocalDate.of(year, month, dayOfMonth);
2231 }
2232
2233 }