1 /*
2 * Copyright (c) 2012, 2016, 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/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 private static final long serialVersionUID = 2942565459149668126L;
161 /**
162 * The number of days in a 400 year cycle.
163 */
164 private static final int DAYS_PER_CYCLE = 146097;
165 /**
166 * The number of days from year zero to year 1970.
167 * There are five 400 year cycles from year zero to 2000.
168 * There are 7 leap years from 1970 to 2000.
169 */
170 static final long DAYS_0000_TO_1970 = (DAYS_PER_CYCLE * 5L) - (30L * 365L + 7L);
171
172 /**
173 * The year.
174 */
175 private final int year;
176 /**
177 * The month-of-year.
178 */
179 private final short month;
180 /**
181 * The day-of-month.
182 */
183 private final short day;
184
185 //-----------------------------------------------------------------------
186 /**
187 * Obtains the current date from the system clock in the default time-zone.
188 * <p>
189 * This will query the {@link Clock#systemDefaultZone() system clock} in the default
190 * time-zone to obtain the current date.
191 * <p>
192 * Using this method will prevent the ability to use an alternate clock for testing
193 * because the clock is hard-coded.
194 *
195 * @return the current date using the system clock and default time-zone, not null
196 */
197 public static LocalDate now() {
198 return now(Clock.systemDefaultZone());
199 }
200
201 /**
202 * Obtains the current date from the system clock in the specified time-zone.
203 * <p>
204 * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date.
205 * Specifying the time-zone avoids dependence on the default time-zone.
206 * <p>
207 * Using this method will prevent the ability to use an alternate clock for testing
208 * because the clock is hard-coded.
209 *
210 * @param zone the zone ID to use, not null
211 * @return the current date using the system clock, not null
212 */
213 public static LocalDate now(ZoneId zone) {
214 return now(Clock.system(zone));
215 }
216
217 /**
218 * Obtains the current date from the specified clock.
219 * <p>
220 * This will query the specified clock to obtain the current date - today.
221 * Using this method allows the use of an alternate clock for testing.
222 * The alternate clock may be introduced using {@link Clock dependency injection}.
223 *
224 * @param clock the clock to use, not null
225 * @return the current date, not null
226 */
227 public static LocalDate now(Clock clock) {
228 Objects.requireNonNull(clock, "clock");
229 final Instant now = clock.instant(); // called once
230 return ofInstant(now, clock.getZone());
231 }
232
233 //-----------------------------------------------------------------------
234 /**
235 * Obtains an instance of {@code LocalDate} from a year, month and day.
236 * <p>
237 * This returns a {@code LocalDate} with the specified year, month and day-of-month.
238 * The day must be valid for the year and month, otherwise an exception will be thrown.
239 *
240 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
241 * @param month the month-of-year to represent, not null
242 * @param dayOfMonth the day-of-month to represent, from 1 to 31
243 * @return the local date, not null
244 * @throws DateTimeException if the value of any field is out of range,
245 * or if the day-of-month is invalid for the month-year
246 */
247 public static LocalDate of(int year, Month month, int dayOfMonth) {
248 YEAR.checkValidValue(year);
249 Objects.requireNonNull(month, "month");
250 DAY_OF_MONTH.checkValidValue(dayOfMonth);
251 return create(year, month.getValue(), dayOfMonth);
252 }
253
254 /**
255 * Obtains an instance of {@code LocalDate} from a year, month and day.
256 * <p>
257 * This returns a {@code LocalDate} with the specified year, month and day-of-month.
258 * The day must be valid for the year and month, otherwise an exception will be thrown.
259 *
260 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
261 * @param month the month-of-year to represent, from 1 (January) to 12 (December)
262 * @param dayOfMonth the day-of-month to represent, from 1 to 31
263 * @return the local date, not null
264 * @throws DateTimeException if the value of any field is out of range,
265 * or if the day-of-month is invalid for the month-year
266 */
267 public static LocalDate of(int year, int month, int dayOfMonth) {
268 YEAR.checkValidValue(year);
269 MONTH_OF_YEAR.checkValidValue(month);
270 DAY_OF_MONTH.checkValidValue(dayOfMonth);
271 return create(year, month, dayOfMonth);
272 }
273
274 //-----------------------------------------------------------------------
275 /**
276 * Obtains an instance of {@code LocalDate} from a year and day-of-year.
277 * <p>
278 * This returns a {@code LocalDate} with the specified year and day-of-year.
279 * The day-of-year must be valid for the year, otherwise an exception will be thrown.
280 *
281 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
282 * @param dayOfYear the day-of-year to represent, from 1 to 366
283 * @return the local date, not null
284 * @throws DateTimeException if the value of any field is out of range,
285 * or if the day-of-year is invalid for the year
286 */
287 public static LocalDate ofYearDay(int year, int dayOfYear) {
288 YEAR.checkValidValue(year);
289 DAY_OF_YEAR.checkValidValue(dayOfYear);
290 boolean leap = IsoChronology.INSTANCE.isLeapYear(year);
291 if (dayOfYear == 366 && leap == false) {
292 throw new DateTimeException("Invalid date 'DayOfYear 366' as '" + year + "' is not a leap year");
293 }
294 Month moy = Month.of((dayOfYear - 1) / 31 + 1);
295 int monthEnd = moy.firstDayOfYear(leap) + moy.length(leap) - 1;
296 if (dayOfYear > monthEnd) {
297 moy = moy.plus(1);
298 }
299 int dom = dayOfYear - moy.firstDayOfYear(leap) + 1;
300 return new LocalDate(year, moy.getValue(), dom);
301 }
302
303 //-----------------------------------------------------------------------
304 /**
305 * Obtains an instance of {@code LocalDate} from an {@code Instant} and zone ID.
306 * <p>
307 * This creates a local date based on the specified instant.
308 * First, the offset from UTC/Greenwich is obtained using the zone ID and instant,
309 * which is simple as there is only one valid offset for each instant.
310 * Then, the instant and offset are used to calculate the local date.
311 *
312 * @param instant the instant to create the date from, not null
313 * @param zone the time-zone, which may be an offset, not null
314 * @return the local date, not null
315 * @throws DateTimeException if the result exceeds the supported range
316 * @since 9
317 */
318 public static LocalDate ofInstant(Instant instant, ZoneId zone) {
319 Objects.requireNonNull(instant, "instant");
320 Objects.requireNonNull(zone, "zone");
321 ZoneRules rules = zone.getRules();
322 ZoneOffset offset = rules.getOffset(instant);
323 long localSecond = instant.getEpochSecond() + offset.getTotalSeconds();
324 long localEpochDay = Math.floorDiv(localSecond, SECONDS_PER_DAY);
325 return ofEpochDay(localEpochDay);
326 }
327
328 //-----------------------------------------------------------------------
329 /**
330 * Obtains an instance of {@code LocalDate} from the epoch day count.
331 * <p>
332 * This returns a {@code LocalDate} with the specified epoch-day.
333 * The {@link ChronoField#EPOCH_DAY EPOCH_DAY} is a simple incrementing count
334 * of days where day 0 is 1970-01-01. Negative numbers represent earlier days.
335 *
336 * @param epochDay the Epoch Day to convert, based on the epoch 1970-01-01
337 * @return the local date, not null
338 * @throws DateTimeException if the epoch day exceeds the supported date range
339 */
340 public static LocalDate ofEpochDay(long epochDay) {
341 EPOCH_DAY.checkValidValue(epochDay);
342 long zeroDay = epochDay + DAYS_0000_TO_1970;
343 // find the march-based year
344 zeroDay -= 60; // adjust to 0000-03-01 so leap day is at end of four year cycle
345 long adjust = 0;
346 if (zeroDay < 0) {
347 // adjust negative years to positive for calculation
348 long adjustCycles = (zeroDay + 1) / DAYS_PER_CYCLE - 1;
349 adjust = adjustCycles * 400;
350 zeroDay += -adjustCycles * DAYS_PER_CYCLE;
351 }
352 long yearEst = (400 * zeroDay + 591) / DAYS_PER_CYCLE;
353 long doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
354 if (doyEst < 0) {
355 // fix estimate
356 yearEst--;
357 doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
358 }
359 yearEst += adjust; // reset any negative year
360 int marchDoy0 = (int) doyEst;
361
362 // convert march-based values back to january-based
363 int marchMonth0 = (marchDoy0 * 5 + 2) / 153;
364 int month = (marchMonth0 + 2) % 12 + 1;
365 int dom = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1;
366 yearEst += marchMonth0 / 10;
367
368 // check year now we are certain it is correct
369 int year = YEAR.checkValidIntValue(yearEst);
370 return new LocalDate(year, month, dom);
371 }
372
373 //-----------------------------------------------------------------------
374 /**
375 * Obtains an instance of {@code LocalDate} from a temporal object.
376 * <p>
377 * This obtains a local date based on the specified temporal.
378 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
379 * which this factory converts to an instance of {@code LocalDate}.
380 * <p>
381 * The conversion uses the {@link TemporalQueries#localDate()} query, which relies
382 * on extracting the {@link ChronoField#EPOCH_DAY EPOCH_DAY} field.
383 * <p>
384 * This method matches the signature of the functional interface {@link TemporalQuery}
385 * allowing it to be used as a query via method reference, {@code LocalDate::from}.
386 *
387 * @param temporal the temporal object to convert, not null
388 * @return the local date, not null
389 * @throws DateTimeException if unable to convert to a {@code LocalDate}
390 */
391 public static LocalDate from(TemporalAccessor temporal) {
392 Objects.requireNonNull(temporal, "temporal");
393 LocalDate date = temporal.query(TemporalQueries.localDate());
394 if (date == null) {
395 throw new DateTimeException("Unable to obtain LocalDate from TemporalAccessor: " +
396 temporal + " of type " + temporal.getClass().getName());
397 }
398 return date;
399 }
400
401 //-----------------------------------------------------------------------
402 /**
403 * Obtains an instance of {@code LocalDate} from a text string such as {@code 2007-12-03}.
404 * <p>
405 * The string must represent a valid date and is parsed using
406 * {@link java.time.format.DateTimeFormatter#ISO_LOCAL_DATE}.
407 *
408 * @param text the text to parse such as "2007-12-03", not null
409 * @return the parsed local date, not null
410 * @throws DateTimeParseException if the text cannot be parsed
411 */
412 public static LocalDate parse(CharSequence text) {
413 return parse(text, DateTimeFormatter.ISO_LOCAL_DATE);
414 }
415
416 /**
417 * Obtains an instance of {@code LocalDate} from a text string using a specific formatter.
418 * <p>
419 * The text is parsed using the formatter, returning a date.
420 *
421 * @param text the text to parse, not null
422 * @param formatter the formatter to use, not null
423 * @return the parsed local date, not null
424 * @throws DateTimeParseException if the text cannot be parsed
425 */
426 public static LocalDate parse(CharSequence text, DateTimeFormatter formatter) {
427 Objects.requireNonNull(formatter, "formatter");
428 return formatter.parse(text, LocalDate::from);
429 }
430
431 //-----------------------------------------------------------------------
432 /**
433 * Creates a local date from the year, month and day fields.
434 *
435 * @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
436 * @param month the month-of-year to represent, from 1 to 12, validated
437 * @param dayOfMonth the day-of-month to represent, validated from 1 to 31
438 * @return the local date, not null
439 * @throws DateTimeException if the day-of-month is invalid for the month-year
440 */
441 private static LocalDate create(int year, int month, int dayOfMonth) {
442 if (dayOfMonth > 28) {
443 int dom = 31;
444 switch (month) {
445 case 2:
446 dom = (IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
447 break;
448 case 4:
449 case 6:
450 case 9:
451 case 11:
452 dom = 30;
453 break;
454 }
455 if (dayOfMonth > dom) {
456 if (dayOfMonth == 29) {
457 throw new DateTimeException("Invalid date 'February 29' as '" + year + "' is not a leap year");
458 } else {
459 throw new DateTimeException("Invalid date '" + Month.of(month).name() + " " + dayOfMonth + "'");
460 }
461 }
462 }
463 return new LocalDate(year, month, dayOfMonth);
464 }
465
466 /**
467 * Resolves the date, resolving days past the end of month.
468 *
469 * @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
470 * @param month the month-of-year to represent, validated from 1 to 12
471 * @param day the day-of-month to represent, validated from 1 to 31
472 * @return the resolved date, not null
473 */
474 private static LocalDate resolvePreviousValid(int year, int month, int day) {
475 switch (month) {
476 case 2:
477 day = Math.min(day, IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
478 break;
479 case 4:
480 case 6:
481 case 9:
482 case 11:
483 day = Math.min(day, 30);
484 break;
485 }
486 return new LocalDate(year, month, day);
487 }
488
489 /**
490 * Constructor, previously validated.
491 *
492 * @param year the year to represent, from MIN_YEAR to MAX_YEAR
493 * @param month the month-of-year to represent, not null
494 * @param dayOfMonth the day-of-month to represent, valid for year-month, from 1 to 31
495 */
496 private LocalDate(int year, int month, int dayOfMonth) {
497 this.year = year;
498 this.month = (short) month;
499 this.day = (short) dayOfMonth;
500 }
501
502 //-----------------------------------------------------------------------
503 /**
504 * Checks if the specified field is supported.
505 * <p>
506 * This checks if this date can be queried for the specified field.
507 * If false, then calling the {@link #range(TemporalField) range},
508 * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
509 * methods will throw an exception.
510 * <p>
511 * If the field is a {@link ChronoField} then the query is implemented here.
512 * The supported fields are:
513 * <ul>
514 * <li>{@code DAY_OF_WEEK}
515 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH}
516 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR}
517 * <li>{@code DAY_OF_MONTH}
518 * <li>{@code DAY_OF_YEAR}
519 * <li>{@code EPOCH_DAY}
520 * <li>{@code ALIGNED_WEEK_OF_MONTH}
521 * <li>{@code ALIGNED_WEEK_OF_YEAR}
522 * <li>{@code MONTH_OF_YEAR}
523 * <li>{@code PROLEPTIC_MONTH}
524 * <li>{@code YEAR_OF_ERA}
525 * <li>{@code YEAR}
526 * <li>{@code ERA}
527 * </ul>
528 * All other {@code ChronoField} instances will return false.
529 * <p>
530 * If the field is not a {@code ChronoField}, then the result of this method
531 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
532 * passing {@code this} as the argument.
533 * Whether the field is supported is determined by the field.
534 *
535 * @param field the field to check, null returns false
536 * @return true if the field is supported on this date, false if not
537 */
538 @Override // override for Javadoc
539 public boolean isSupported(TemporalField field) {
540 return ChronoLocalDate.super.isSupported(field);
541 }
542
543 /**
544 * Checks if the specified unit is supported.
545 * <p>
546 * This checks if the specified unit can be added to, or subtracted from, this date.
547 * If false, then calling the {@link #plus(long, TemporalUnit)} and
548 * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
549 * <p>
550 * If the unit is a {@link ChronoUnit} then the query is implemented here.
551 * The supported units are:
552 * <ul>
553 * <li>{@code DAYS}
554 * <li>{@code WEEKS}
555 * <li>{@code MONTHS}
556 * <li>{@code YEARS}
557 * <li>{@code DECADES}
558 * <li>{@code CENTURIES}
559 * <li>{@code MILLENNIA}
560 * <li>{@code ERAS}
561 * </ul>
562 * All other {@code ChronoUnit} instances will return false.
563 * <p>
564 * If the unit is not a {@code ChronoUnit}, then the result of this method
565 * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
566 * passing {@code this} as the argument.
567 * Whether the unit is supported is determined by the unit.
568 *
569 * @param unit the unit to check, null returns false
570 * @return true if the unit can be added/subtracted, false if not
571 */
572 @Override // override for Javadoc
573 public boolean isSupported(TemporalUnit unit) {
574 return ChronoLocalDate.super.isSupported(unit);
575 }
576
577 //-----------------------------------------------------------------------
578 /**
579 * Gets the range of valid values for the specified field.
580 * <p>
581 * The range object expresses the minimum and maximum valid values for a field.
582 * This date is used to enhance the accuracy of the returned range.
583 * If it is not possible to return the range, because the field is not supported
584 * or for some other reason, an exception is thrown.
585 * <p>
586 * If the field is a {@link ChronoField} then the query is implemented here.
587 * The {@link #isSupported(TemporalField) supported fields} will return
588 * appropriate range instances.
589 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
590 * <p>
591 * If the field is not a {@code ChronoField}, then the result of this method
592 * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
593 * passing {@code this} as the argument.
594 * Whether the range can be obtained is determined by the field.
595 *
596 * @param field the field to query the range for, not null
597 * @return the range of valid values for the field, not null
598 * @throws DateTimeException if the range for the field cannot be obtained
599 * @throws UnsupportedTemporalTypeException if the field is not supported
600 */
601 @Override
602 public ValueRange range(TemporalField field) {
603 if (field instanceof ChronoField) {
604 ChronoField f = (ChronoField) field;
605 if (f.isDateBased()) {
606 switch (f) {
607 case DAY_OF_MONTH: return ValueRange.of(1, lengthOfMonth());
608 case DAY_OF_YEAR: return ValueRange.of(1, lengthOfYear());
609 case ALIGNED_WEEK_OF_MONTH: return ValueRange.of(1, getMonth() == Month.FEBRUARY && isLeapYear() == false ? 4 : 5);
610 case YEAR_OF_ERA:
611 return (getYear() <= 0 ? ValueRange.of(1, Year.MAX_VALUE + 1) : ValueRange.of(1, Year.MAX_VALUE));
612 }
613 return field.range();
614 }
615 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
616 }
617 return field.rangeRefinedBy(this);
618 }
619
620 /**
621 * Gets the value of the specified field from this date as an {@code int}.
622 * <p>
623 * This queries this date for the value of the specified field.
624 * The returned value will always be within the valid range of values for the field.
625 * If it is not possible to return the value, because the field is not supported
626 * or for some other reason, an exception is thrown.
627 * <p>
628 * If the field is a {@link ChronoField} then the query is implemented here.
629 * The {@link #isSupported(TemporalField) supported fields} will return valid
630 * values based on this date, except {@code EPOCH_DAY} and {@code PROLEPTIC_MONTH}
631 * which are too large to fit in an {@code int} and throw an {@code UnsupportedTemporalTypeException}.
632 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
633 * <p>
634 * If the field is not a {@code ChronoField}, then the result of this method
635 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
636 * passing {@code this} as the argument. Whether the value can be obtained,
637 * and what the value represents, is determined by the field.
638 *
639 * @param field the field to get, not null
640 * @return the value for the field
641 * @throws DateTimeException if a value for the field cannot be obtained or
642 * the value is outside the range of valid values for the field
643 * @throws UnsupportedTemporalTypeException if the field is not supported or
644 * the range of values exceeds an {@code int}
645 * @throws ArithmeticException if numeric overflow occurs
646 */
647 @Override // override for Javadoc and performance
648 public int get(TemporalField field) {
649 if (field instanceof ChronoField) {
650 return get0(field);
651 }
652 return ChronoLocalDate.super.get(field);
653 }
654
655 /**
656 * Gets the value of the specified field from this date as a {@code long}.
657 * <p>
658 * This queries this date for the value of the specified field.
659 * If it is not possible to return the value, because the field is not supported
660 * or for some other reason, an exception is thrown.
661 * <p>
662 * If the field is a {@link ChronoField} then the query is implemented here.
663 * The {@link #isSupported(TemporalField) supported fields} will return valid
664 * values based on this date.
665 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
666 * <p>
667 * If the field is not a {@code ChronoField}, then the result of this method
668 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
669 * passing {@code this} as the argument. Whether the value can be obtained,
670 * and what the value represents, is determined by the field.
671 *
672 * @param field the field to get, not null
673 * @return the value for the field
674 * @throws DateTimeException if a value for the field cannot be obtained
675 * @throws UnsupportedTemporalTypeException if the field is not supported
676 * @throws ArithmeticException if numeric overflow occurs
677 */
678 @Override
679 public long getLong(TemporalField field) {
680 if (field instanceof ChronoField) {
681 if (field == EPOCH_DAY) {
682 return toEpochDay();
683 }
684 if (field == PROLEPTIC_MONTH) {
685 return getProlepticMonth();
686 }
687 return get0(field);
688 }
689 return field.getFrom(this);
690 }
691
692 private int get0(TemporalField field) {
693 switch ((ChronoField) field) {
694 case DAY_OF_WEEK: return getDayOfWeek().getValue();
695 case ALIGNED_DAY_OF_WEEK_IN_MONTH: return ((day - 1) % 7) + 1;
696 case ALIGNED_DAY_OF_WEEK_IN_YEAR: return ((getDayOfYear() - 1) % 7) + 1;
697 case DAY_OF_MONTH: return day;
698 case DAY_OF_YEAR: return getDayOfYear();
699 case EPOCH_DAY: throw new UnsupportedTemporalTypeException("Invalid field 'EpochDay' for get() method, use getLong() instead");
700 case ALIGNED_WEEK_OF_MONTH: return ((day - 1) / 7) + 1;
701 case ALIGNED_WEEK_OF_YEAR: return ((getDayOfYear() - 1) / 7) + 1;
702 case MONTH_OF_YEAR: return month;
703 case PROLEPTIC_MONTH: throw new UnsupportedTemporalTypeException("Invalid field 'ProlepticMonth' for get() method, use getLong() instead");
704 case YEAR_OF_ERA: return (year >= 1 ? year : 1 - year);
705 case YEAR: return year;
706 case ERA: return (year >= 1 ? 1 : 0);
707 }
708 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
709 }
710
711 private long getProlepticMonth() {
712 return (year * 12L + month - 1);
713 }
714
715 //-----------------------------------------------------------------------
716 /**
717 * Gets the chronology of this date, which is the ISO calendar system.
718 * <p>
719 * The {@code Chronology} represents the calendar system in use.
720 * The ISO-8601 calendar system is the modern civil calendar system used today
721 * in most of the world. It is equivalent to the proleptic Gregorian calendar
722 * system, in which today's rules for leap years are applied for all time.
723 *
724 * @return the ISO chronology, not null
725 */
726 @Override
727 public IsoChronology getChronology() {
728 return IsoChronology.INSTANCE;
729 }
730
731 /**
732 * Gets the era applicable at this date.
733 * <p>
734 * The official ISO-8601 standard does not define eras, however {@code IsoChronology} does.
735 * It defines two eras, 'CE' from year one onwards and 'BCE' from year zero backwards.
736 * Since dates before the Julian-Gregorian cutover are not in line with history,
737 * the cutover between 'BCE' and 'CE' is also not aligned with the commonly used
738 * eras, often referred to using 'BC' and 'AD'.
739 * <p>
740 * Users of this class should typically ignore this method as it exists primarily
741 * to fulfill the {@link ChronoLocalDate} contract where it is necessary to support
742 * the Japanese calendar system.
743 *
744 * @return the IsoEra applicable at this date, not null
745 */
746 @Override // override for Javadoc
747 public IsoEra getEra() {
748 return (getYear() >= 1 ? IsoEra.CE : IsoEra.BCE);
749 }
750
751 /**
752 * Gets the year field.
753 * <p>
754 * This method returns the primitive {@code int} value for the year.
755 * <p>
756 * The year returned by this method is proleptic as per {@code get(YEAR)}.
757 * To obtain the year-of-era, use {@code get(YEAR_OF_ERA)}.
758 *
759 * @return the year, from MIN_YEAR to MAX_YEAR
760 */
761 public int getYear() {
762 return year;
763 }
764
765 /**
766 * Gets the month-of-year field from 1 to 12.
767 * <p>
768 * This method returns the month as an {@code int} from 1 to 12.
769 * Application code is frequently clearer if the enum {@link Month}
770 * is used by calling {@link #getMonth()}.
771 *
772 * @return the month-of-year, from 1 to 12
773 * @see #getMonth()
774 */
775 public int getMonthValue() {
776 return month;
777 }
778
779 /**
780 * Gets the month-of-year field using the {@code Month} enum.
781 * <p>
782 * This method returns the enum {@link Month} for the month.
783 * This avoids confusion as to what {@code int} values mean.
784 * If you need access to the primitive {@code int} value then the enum
785 * provides the {@link Month#getValue() int value}.
786 *
787 * @return the month-of-year, not null
788 * @see #getMonthValue()
789 */
790 public Month getMonth() {
791 return Month.of(month);
792 }
793
794 /**
795 * Gets the day-of-month field.
796 * <p>
797 * This method returns the primitive {@code int} value for the day-of-month.
798 *
799 * @return the day-of-month, from 1 to 31
800 */
801 public int getDayOfMonth() {
802 return day;
803 }
804
805 /**
806 * Gets the day-of-year field.
807 * <p>
808 * This method returns the primitive {@code int} value for the day-of-year.
809 *
810 * @return the day-of-year, from 1 to 365, or 366 in a leap year
811 */
812 public int getDayOfYear() {
813 return getMonth().firstDayOfYear(isLeapYear()) + day - 1;
814 }
815
816 /**
817 * Gets the day-of-week field, which is an enum {@code DayOfWeek}.
818 * <p>
819 * This method returns the enum {@link DayOfWeek} for the day-of-week.
820 * This avoids confusion as to what {@code int} values mean.
821 * If you need access to the primitive {@code int} value then the enum
822 * provides the {@link DayOfWeek#getValue() int value}.
823 * <p>
824 * Additional information can be obtained from the {@code DayOfWeek}.
825 * This includes textual names of the values.
826 *
827 * @return the day-of-week, not null
828 */
829 public DayOfWeek getDayOfWeek() {
830 int dow0 = Math.floorMod(toEpochDay() + 3, 7);
831 return DayOfWeek.of(dow0 + 1);
832 }
833
834 //-----------------------------------------------------------------------
835 /**
836 * Checks if the year is a leap year, according to the ISO proleptic
837 * calendar system rules.
838 * <p>
839 * This method applies the current rules for leap years across the whole time-line.
840 * In general, a year is a leap year if it is divisible by four without
841 * remainder. However, years divisible by 100, are not leap years, with
842 * the exception of years divisible by 400 which are.
843 * <p>
844 * For example, 1904 is a leap year it is divisible by 4.
845 * 1900 was not a leap year as it is divisible by 100, however 2000 was a
846 * leap year as it is divisible by 400.
847 * <p>
848 * The calculation is proleptic - applying the same rules into the far future and far past.
849 * This is historically inaccurate, but is correct for the ISO-8601 standard.
850 *
851 * @return true if the year is leap, false otherwise
852 */
853 @Override // override for Javadoc and performance
854 public boolean isLeapYear() {
855 return IsoChronology.INSTANCE.isLeapYear(year);
856 }
857
858 /**
859 * Returns the length of the month represented by this date.
860 * <p>
861 * This returns the length of the month in days.
862 * For example, a date in January would return 31.
863 *
864 * @return the length of the month in days
865 */
866 @Override
867 public int lengthOfMonth() {
868 switch (month) {
869 case 2:
870 return (isLeapYear() ? 29 : 28);
871 case 4:
872 case 6:
873 case 9:
874 case 11:
875 return 30;
876 default:
877 return 31;
878 }
879 }
880
881 /**
882 * Returns the length of the year represented by this date.
883 * <p>
884 * This returns the length of the year in days, either 365 or 366.
885 *
886 * @return 366 if the year is leap, 365 otherwise
887 */
888 @Override // override for Javadoc and performance
889 public int lengthOfYear() {
890 return (isLeapYear() ? 366 : 365);
891 }
892
893 //-----------------------------------------------------------------------
894 /**
895 * Returns an adjusted copy of this date.
896 * <p>
897 * This returns a {@code LocalDate}, based on this one, with the date adjusted.
898 * The adjustment takes place using the specified adjuster strategy object.
899 * Read the documentation of the adjuster to understand what adjustment will be made.
900 * <p>
901 * A simple adjuster might simply set the one of the fields, such as the year field.
902 * A more complex adjuster might set the date to the last day of the month.
903 * <p>
904 * A selection of common adjustments is provided in
905 * {@link java.time.temporal.TemporalAdjusters TemporalAdjusters}.
906 * These include finding the "last day of the month" and "next Wednesday".
907 * Key date-time classes also implement the {@code TemporalAdjuster} interface,
908 * such as {@link Month} and {@link java.time.MonthDay MonthDay}.
909 * The adjuster is responsible for handling special cases, such as the varying
910 * lengths of month and leap years.
911 * <p>
912 * For example this code returns a date on the last day of July:
913 * <pre>
914 * import static java.time.Month.*;
915 * import static java.time.temporal.TemporalAdjusters.*;
916 *
917 * result = localDate.with(JULY).with(lastDayOfMonth());
918 * </pre>
919 * <p>
920 * The result of this method is obtained by invoking the
921 * {@link TemporalAdjuster#adjustInto(Temporal)} method on the
922 * specified adjuster passing {@code this} as the argument.
923 * <p>
924 * This instance is immutable and unaffected by this method call.
925 *
926 * @param adjuster the adjuster to use, not null
927 * @return a {@code LocalDate} based on {@code this} with the adjustment made, not null
928 * @throws DateTimeException if the adjustment cannot be made
929 * @throws ArithmeticException if numeric overflow occurs
930 */
931 @Override
932 public LocalDate with(TemporalAdjuster adjuster) {
933 // optimizations
934 if (adjuster instanceof LocalDate) {
935 return (LocalDate) adjuster;
936 }
937 return (LocalDate) adjuster.adjustInto(this);
938 }
939
940 /**
941 * Returns a copy of this date with the specified field set to a new value.
942 * <p>
943 * This returns a {@code LocalDate}, based on this one, with the value
944 * for the specified field changed.
945 * This can be used to change any supported field, such as the year, month or day-of-month.
946 * If it is not possible to set the value, because the field is not supported or for
947 * some other reason, an exception is thrown.
948 * <p>
949 * In some cases, changing the specified field can cause the resulting date to become invalid,
950 * such as changing the month from 31st January to February would make the day-of-month invalid.
951 * In cases like this, the field is responsible for resolving the date. Typically it will choose
952 * the previous valid date, which would be the last valid day of February in this example.
953 * <p>
954 * If the field is a {@link ChronoField} then the adjustment is implemented here.
955 * The supported fields behave as follows:
956 * <ul>
957 * <li>{@code DAY_OF_WEEK} -
958 * Returns a {@code LocalDate} with the specified day-of-week.
959 * The date is adjusted up to 6 days forward or backward within the boundary
960 * of a Monday to Sunday week.
961 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH} -
962 * Returns a {@code LocalDate} with the specified aligned-day-of-week.
963 * The date is adjusted to the specified month-based aligned-day-of-week.
964 * Aligned weeks are counted such that the first week of a given month starts
965 * on the first day of that month.
966 * This may cause the date to be moved up to 6 days into the following month.
967 * <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR} -
968 * Returns a {@code LocalDate} with the specified aligned-day-of-week.
969 * The date is adjusted to the specified year-based aligned-day-of-week.
970 * Aligned weeks are counted such that the first week of a given year starts
971 * on the first day of that year.
972 * This may cause the date to be moved up to 6 days into the following year.
973 * <li>{@code DAY_OF_MONTH} -
974 * Returns a {@code LocalDate} with the specified day-of-month.
975 * The month and year will be unchanged. If the day-of-month is invalid for the
976 * year and month, then a {@code DateTimeException} is thrown.
977 * <li>{@code DAY_OF_YEAR} -
978 * Returns a {@code LocalDate} with the specified day-of-year.
979 * The year will be unchanged. If the day-of-year is invalid for the
980 * year, then a {@code DateTimeException} is thrown.
981 * <li>{@code EPOCH_DAY} -
982 * Returns a {@code LocalDate} with the specified epoch-day.
983 * This completely replaces the date and is equivalent to {@link #ofEpochDay(long)}.
984 * <li>{@code ALIGNED_WEEK_OF_MONTH} -
985 * Returns a {@code LocalDate} with the specified aligned-week-of-month.
986 * Aligned weeks are counted such that the first week of a given month starts
987 * on the first day of that month.
988 * This adjustment moves the date in whole week chunks to match the specified week.
989 * The result will have the same day-of-week as this date.
990 * This may cause the date to be moved into the following month.
991 * <li>{@code ALIGNED_WEEK_OF_YEAR} -
992 * Returns a {@code LocalDate} with the specified aligned-week-of-year.
993 * Aligned weeks are counted such that the first week of a given year starts
994 * on the first day of that year.
995 * This adjustment moves the date in whole week chunks to match the specified week.
996 * The result will have the same day-of-week as this date.
997 * This may cause the date to be moved into the following year.
998 * <li>{@code MONTH_OF_YEAR} -
999 * Returns a {@code LocalDate} with the specified month-of-year.
1000 * The year will be unchanged. The day-of-month will also be unchanged,
1001 * unless it would be invalid for the new month and year. In that case, the
1002 * day-of-month is adjusted to the maximum valid value for the new month and year.
1003 * <li>{@code PROLEPTIC_MONTH} -
1004 * Returns a {@code LocalDate} with the specified proleptic-month.
1005 * The day-of-month will be unchanged, unless it would be invalid for the new month
1006 * and year. In that case, the day-of-month is adjusted to the maximum valid value
1007 * for the new month and year.
1008 * <li>{@code YEAR_OF_ERA} -
1009 * Returns a {@code LocalDate} with the specified year-of-era.
1010 * The era and month will be unchanged. The day-of-month will also be unchanged,
1011 * unless it would be invalid for the new month and year. In that case, the
1012 * day-of-month is adjusted to the maximum valid value for the new month and year.
1013 * <li>{@code YEAR} -
1014 * Returns a {@code LocalDate} with the specified year.
1015 * The month will be unchanged. The day-of-month will also be unchanged,
1016 * unless it would be invalid for the new month and year. In that case, the
1017 * day-of-month is adjusted to the maximum valid value for the new month and year.
1018 * <li>{@code ERA} -
1019 * Returns a {@code LocalDate} with the specified era.
1020 * The year-of-era and month will be unchanged. The day-of-month will also be unchanged,
1021 * unless it would be invalid for the new month and year. In that case, the
1022 * day-of-month is adjusted to the maximum valid value for the new month and year.
1023 * </ul>
1024 * <p>
1025 * In all cases, if the new value is outside the valid range of values for the field
1026 * then a {@code DateTimeException} will be thrown.
1027 * <p>
1028 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
1029 * <p>
1030 * If the field is not a {@code ChronoField}, then the result of this method
1031 * is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
1032 * passing {@code this} as the argument. In this case, the field determines
1033 * whether and how to adjust the instant.
1034 * <p>
1035 * This instance is immutable and unaffected by this method call.
1036 *
1037 * @param field the field to set in the result, not null
1038 * @param newValue the new value of the field in the result
1039 * @return a {@code LocalDate} based on {@code this} with the specified field set, not null
1040 * @throws DateTimeException if the field cannot be set
1041 * @throws UnsupportedTemporalTypeException if the field is not supported
1042 * @throws ArithmeticException if numeric overflow occurs
1043 */
1044 @Override
1045 public LocalDate with(TemporalField field, long newValue) {
1046 if (field instanceof ChronoField) {
1047 ChronoField f = (ChronoField) field;
1048 f.checkValidValue(newValue);
1049 switch (f) {
1050 case DAY_OF_WEEK: return plusDays(newValue - getDayOfWeek().getValue());
1051 case ALIGNED_DAY_OF_WEEK_IN_MONTH: return plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_MONTH));
1052 case ALIGNED_DAY_OF_WEEK_IN_YEAR: return plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_YEAR));
1053 case DAY_OF_MONTH: return withDayOfMonth((int) newValue);
1054 case DAY_OF_YEAR: return withDayOfYear((int) newValue);
1055 case EPOCH_DAY: return LocalDate.ofEpochDay(newValue);
1056 case ALIGNED_WEEK_OF_MONTH: return plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_MONTH));
1057 case ALIGNED_WEEK_OF_YEAR: return plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_YEAR));
1058 case MONTH_OF_YEAR: return withMonth((int) newValue);
1059 case PROLEPTIC_MONTH: return plusMonths(newValue - getProlepticMonth());
1060 case YEAR_OF_ERA: return withYear((int) (year >= 1 ? newValue : 1 - newValue));
1061 case YEAR: return withYear((int) newValue);
1062 case ERA: return (getLong(ERA) == newValue ? this : withYear(1 - year));
1063 }
1064 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
1065 }
1066 return field.adjustInto(this, newValue);
1067 }
1068
1069 //-----------------------------------------------------------------------
1070 /**
1071 * Returns a copy of this {@code LocalDate} with the year altered.
1072 * <p>
1073 * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
1074 * <p>
1075 * This instance is immutable and unaffected by this method call.
1076 *
1077 * @param year the year to set in the result, from MIN_YEAR to MAX_YEAR
1078 * @return a {@code LocalDate} based on this date with the requested year, not null
1079 * @throws DateTimeException if the year value is invalid
1080 */
1081 public LocalDate withYear(int year) {
1082 if (this.year == year) {
1083 return this;
1084 }
1085 YEAR.checkValidValue(year);
1086 return resolvePreviousValid(year, month, day);
1087 }
1088
1089 /**
1090 * Returns a copy of this {@code LocalDate} with the month-of-year altered.
1091 * <p>
1092 * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
1093 * <p>
1094 * This instance is immutable and unaffected by this method call.
1095 *
1096 * @param month the month-of-year to set in the result, from 1 (January) to 12 (December)
1097 * @return a {@code LocalDate} based on this date with the requested month, not null
1098 * @throws DateTimeException if the month-of-year value is invalid
1099 */
1100 public LocalDate withMonth(int month) {
1101 if (this.month == month) {
1102 return this;
1103 }
1104 MONTH_OF_YEAR.checkValidValue(month);
1105 return resolvePreviousValid(year, month, day);
1106 }
1107
1108 /**
1109 * Returns a copy of this {@code LocalDate} with the day-of-month altered.
1110 * <p>
1111 * If the resulting date is invalid, an exception is thrown.
1112 * <p>
1113 * This instance is immutable and unaffected by this method call.
1114 *
1115 * @param dayOfMonth the day-of-month to set in the result, from 1 to 28-31
1116 * @return a {@code LocalDate} based on this date with the requested day, not null
1117 * @throws DateTimeException if the day-of-month value is invalid,
1118 * or if the day-of-month is invalid for the month-year
1119 */
1120 public LocalDate withDayOfMonth(int dayOfMonth) {
1121 if (this.day == dayOfMonth) {
1122 return this;
1123 }
1124 return of(year, month, dayOfMonth);
1125 }
1126
1127 /**
1128 * Returns a copy of this {@code LocalDate} with the day-of-year altered.
1129 * <p>
1130 * If the resulting date is invalid, an exception is thrown.
1131 * <p>
1132 * This instance is immutable and unaffected by this method call.
1133 *
1134 * @param dayOfYear the day-of-year to set in the result, from 1 to 365-366
1135 * @return a {@code LocalDate} based on this date with the requested day, not null
1136 * @throws DateTimeException if the day-of-year value is invalid,
1137 * or if the day-of-year is invalid for the year
1138 */
1139 public LocalDate withDayOfYear(int dayOfYear) {
1140 if (this.getDayOfYear() == dayOfYear) {
1141 return this;
1142 }
1143 return ofYearDay(year, dayOfYear);
1144 }
1145
1146 //-----------------------------------------------------------------------
1147 /**
1148 * Returns a copy of this date with the specified amount added.
1149 * <p>
1150 * This returns a {@code LocalDate}, based on this one, with the specified amount added.
1151 * The amount is typically {@link Period} but may be any other type implementing
1152 * the {@link TemporalAmount} interface.
1153 * <p>
1154 * The calculation is delegated to the amount object by calling
1155 * {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
1156 * to implement the addition in any way it wishes, however it typically
1157 * calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
1158 * of the amount implementation to determine if it can be successfully added.
1159 * <p>
1160 * This instance is immutable and unaffected by this method call.
1161 *
1162 * @param amountToAdd the amount to add, not null
1163 * @return a {@code LocalDate} based on this date with the addition made, not null
1164 * @throws DateTimeException if the addition cannot be made
1165 * @throws ArithmeticException if numeric overflow occurs
1166 */
1167 @Override
1168 public LocalDate plus(TemporalAmount amountToAdd) {
1169 if (amountToAdd instanceof Period) {
1170 Period periodToAdd = (Period) amountToAdd;
1171 return plusMonths(periodToAdd.toTotalMonths()).plusDays(periodToAdd.getDays());
1172 }
1173 Objects.requireNonNull(amountToAdd, "amountToAdd");
1174 return (LocalDate) amountToAdd.addTo(this);
1175 }
1176
1177 /**
1178 * Returns a copy of this date with the specified amount added.
1179 * <p>
1180 * This returns a {@code LocalDate}, based on this one, with the amount
1181 * in terms of the unit added. If it is not possible to add the amount, because the
1182 * unit is not supported or for some other reason, an exception is thrown.
1183 * <p>
1184 * In some cases, adding the amount can cause the resulting date to become invalid.
1185 * For example, adding one month to 31st January would result in 31st February.
1186 * In cases like this, the unit is responsible for resolving the date.
1187 * Typically it will choose the previous valid date, which would be the last valid
1188 * day of February in this example.
1189 * <p>
1190 * If the field is a {@link ChronoUnit} then the addition is implemented here.
1191 * The supported fields behave as follows:
1192 * <ul>
1193 * <li>{@code DAYS} -
1194 * Returns a {@code LocalDate} with the specified number of days added.
1195 * This is equivalent to {@link #plusDays(long)}.
1196 * <li>{@code WEEKS} -
1197 * Returns a {@code LocalDate} with the specified number of weeks added.
1198 * This is equivalent to {@link #plusWeeks(long)} and uses a 7 day week.
1199 * <li>{@code MONTHS} -
1200 * Returns a {@code LocalDate} with the specified number of months added.
1201 * This is equivalent to {@link #plusMonths(long)}.
1202 * The day-of-month will be unchanged unless it would be invalid for the new
1203 * month and year. In that case, the day-of-month is adjusted to the maximum
1204 * valid value for the new month and year.
1205 * <li>{@code YEARS} -
1206 * Returns a {@code LocalDate} with the specified number of years added.
1207 * This is equivalent to {@link #plusYears(long)}.
1208 * The day-of-month will be unchanged unless it would be invalid for the new
1209 * month and year. In that case, the day-of-month is adjusted to the maximum
1210 * valid value for the new month and year.
1211 * <li>{@code DECADES} -
1212 * Returns a {@code LocalDate} with the specified number of decades added.
1213 * This is equivalent to calling {@link #plusYears(long)} with the amount
1214 * multiplied by 10.
1215 * The day-of-month will be unchanged unless it would be invalid for the new
1216 * month and year. In that case, the day-of-month is adjusted to the maximum
1217 * valid value for the new month and year.
1218 * <li>{@code CENTURIES} -
1219 * Returns a {@code LocalDate} with the specified number of centuries added.
1220 * This is equivalent to calling {@link #plusYears(long)} with the amount
1221 * multiplied by 100.
1222 * The day-of-month will be unchanged unless it would be invalid for the new
1223 * month and year. In that case, the day-of-month is adjusted to the maximum
1224 * valid value for the new month and year.
1225 * <li>{@code MILLENNIA} -
1226 * Returns a {@code LocalDate} with the specified number of millennia added.
1227 * This is equivalent to calling {@link #plusYears(long)} with the amount
1228 * multiplied by 1,000.
1229 * The day-of-month will be unchanged unless it would be invalid for the new
1230 * month and year. In that case, the day-of-month is adjusted to the maximum
1231 * valid value for the new month and year.
1232 * <li>{@code ERAS} -
1233 * Returns a {@code LocalDate} with the specified number of eras added.
1234 * Only two eras are supported so the amount must be one, zero or minus one.
1235 * If the amount is non-zero then the year is changed such that the year-of-era
1236 * is unchanged.
1237 * The day-of-month will be unchanged unless it would be invalid for the new
1238 * month and year. In that case, the day-of-month is adjusted to the maximum
1239 * valid value for the new month and year.
1240 * </ul>
1241 * <p>
1242 * All other {@code ChronoUnit} instances will throw an {@code UnsupportedTemporalTypeException}.
1243 * <p>
1244 * If the field is not a {@code ChronoUnit}, then the result of this method
1245 * is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
1246 * passing {@code this} as the argument. In this case, the unit determines
1247 * whether and how to perform the addition.
1248 * <p>
1249 * This instance is immutable and unaffected by this method call.
1250 *
1251 * @param amountToAdd the amount of the unit to add to the result, may be negative
1252 * @param unit the unit of the amount to add, not null
1253 * @return a {@code LocalDate} based on this date with the specified amount added, not null
1254 * @throws DateTimeException if the addition cannot be made
1255 * @throws UnsupportedTemporalTypeException if the unit is not supported
1256 * @throws ArithmeticException if numeric overflow occurs
1257 */
1258 @Override
1259 public LocalDate plus(long amountToAdd, TemporalUnit unit) {
1260 if (unit instanceof ChronoUnit) {
1261 ChronoUnit f = (ChronoUnit) unit;
1262 switch (f) {
1263 case DAYS: return plusDays(amountToAdd);
1264 case WEEKS: return plusWeeks(amountToAdd);
1265 case MONTHS: return plusMonths(amountToAdd);
1266 case YEARS: return plusYears(amountToAdd);
1267 case DECADES: return plusYears(Math.multiplyExact(amountToAdd, 10));
1268 case CENTURIES: return plusYears(Math.multiplyExact(amountToAdd, 100));
1269 case MILLENNIA: return plusYears(Math.multiplyExact(amountToAdd, 1000));
1270 case ERAS: return with(ERA, Math.addExact(getLong(ERA), amountToAdd));
1271 }
1272 throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1273 }
1274 return unit.addTo(this, amountToAdd);
1275 }
1276
1277 //-----------------------------------------------------------------------
1278 /**
1279 * Returns a copy of this {@code LocalDate} with the specified number of years added.
1280 * <p>
1281 * This method adds the specified amount to the years field in three steps:
1282 * <ol>
1283 * <li>Add the input years to the year field</li>
1284 * <li>Check if the resulting date would be invalid</li>
1285 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1286 * </ol>
1287 * <p>
1288 * For example, 2008-02-29 (leap year) plus one year would result in the
1289 * invalid date 2009-02-29 (standard year). Instead of returning an invalid
1290 * result, the last valid day of the month, 2009-02-28, is selected instead.
1291 * <p>
1292 * This instance is immutable and unaffected by this method call.
1293 *
1294 * @param yearsToAdd the years to add, may be negative
1295 * @return a {@code LocalDate} based on this date with the years added, not null
1296 * @throws DateTimeException if the result exceeds the supported date range
1297 */
1298 public LocalDate plusYears(long yearsToAdd) {
1299 if (yearsToAdd == 0) {
1300 return this;
1301 }
1302 int newYear = YEAR.checkValidIntValue(year + yearsToAdd); // safe overflow
1303 return resolvePreviousValid(newYear, month, day);
1304 }
1305
1306 /**
1307 * Returns a copy of this {@code LocalDate} with the specified number of months added.
1308 * <p>
1309 * This method adds the specified amount to the months field in three steps:
1310 * <ol>
1311 * <li>Add the input months to the month-of-year field</li>
1312 * <li>Check if the resulting date would be invalid</li>
1313 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1314 * </ol>
1315 * <p>
1316 * For example, 2007-03-31 plus one month would result in the invalid date
1317 * 2007-04-31. Instead of returning an invalid result, the last valid day
1318 * of the month, 2007-04-30, is selected instead.
1319 * <p>
1320 * This instance is immutable and unaffected by this method call.
1321 *
1322 * @param monthsToAdd the months to add, may be negative
1323 * @return a {@code LocalDate} based on this date with the months added, not null
1324 * @throws DateTimeException if the result exceeds the supported date range
1325 */
1326 public LocalDate plusMonths(long monthsToAdd) {
1327 if (monthsToAdd == 0) {
1328 return this;
1329 }
1330 long monthCount = year * 12L + (month - 1);
1331 long calcMonths = monthCount + monthsToAdd; // safe overflow
1332 int newYear = YEAR.checkValidIntValue(Math.floorDiv(calcMonths, 12));
1333 int newMonth = Math.floorMod(calcMonths, 12) + 1;
1334 return resolvePreviousValid(newYear, newMonth, day);
1335 }
1336
1337 /**
1338 * Returns a copy of this {@code LocalDate} with the specified number of weeks added.
1339 * <p>
1340 * This method adds the specified amount in weeks to the days field incrementing
1341 * the month and year fields as necessary to ensure the result remains valid.
1342 * The result is only invalid if the maximum/minimum year is exceeded.
1343 * <p>
1344 * For example, 2008-12-31 plus one week would result in 2009-01-07.
1345 * <p>
1346 * This instance is immutable and unaffected by this method call.
1347 *
1348 * @param weeksToAdd the weeks to add, may be negative
1349 * @return a {@code LocalDate} based on this date with the weeks added, not null
1350 * @throws DateTimeException if the result exceeds the supported date range
1351 */
1352 public LocalDate plusWeeks(long weeksToAdd) {
1353 return plusDays(Math.multiplyExact(weeksToAdd, 7));
1354 }
1355
1356 /**
1357 * Returns a copy of this {@code LocalDate} with the specified number of days added.
1358 * <p>
1359 * This method adds the specified amount to the days field incrementing the
1360 * month and year fields as necessary to ensure the result remains valid.
1361 * The result is only invalid if the maximum/minimum year is exceeded.
1362 * <p>
1363 * For example, 2008-12-31 plus one day would result in 2009-01-01.
1364 * <p>
1365 * This instance is immutable and unaffected by this method call.
1366 *
1367 * @param daysToAdd the days to add, may be negative
1368 * @return a {@code LocalDate} based on this date with the days added, not null
1369 * @throws DateTimeException if the result exceeds the supported date range
1370 */
1371 public LocalDate plusDays(long daysToAdd) {
1372 if (daysToAdd == 0) {
1373 return this;
1374 }
1375 long dom = day + daysToAdd;
1376 if (dom > 0) {
1377 if (dom <= 28) {
1378 return new LocalDate(year, month, (int) dom);
1379 } else if (dom <= 59) { // 59th Jan is 28th Feb, 59th Feb is 31st Mar
1380 long monthLen = lengthOfMonth();
1381 if (dom <= monthLen) {
1382 return new LocalDate(year, month, (int) dom);
1383 } else if (month < 12) {
1384 return new LocalDate(year, month + 1, (int) (dom - monthLen));
1385 } else {
1386 YEAR.checkValidValue(year + 1);
1387 return new LocalDate(year + 1, 1, (int) (dom - monthLen));
1388 }
1389 }
1390 }
1391
1392 long mjDay = Math.addExact(toEpochDay(), daysToAdd);
1393 return LocalDate.ofEpochDay(mjDay);
1394 }
1395
1396 //-----------------------------------------------------------------------
1397 /**
1398 * Returns a copy of this date with the specified amount subtracted.
1399 * <p>
1400 * This returns a {@code LocalDate}, based on this one, with the specified amount subtracted.
1401 * The amount is typically {@link Period} but may be any other type implementing
1402 * the {@link TemporalAmount} interface.
1403 * <p>
1404 * The calculation is delegated to the amount object by calling
1405 * {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
1406 * to implement the subtraction in any way it wishes, however it typically
1407 * calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
1408 * of the amount implementation to determine if it can be successfully subtracted.
1409 * <p>
1410 * This instance is immutable and unaffected by this method call.
1411 *
1412 * @param amountToSubtract the amount to subtract, not null
1413 * @return a {@code LocalDate} based on this date with the subtraction made, not null
1414 * @throws DateTimeException if the subtraction cannot be made
1415 * @throws ArithmeticException if numeric overflow occurs
1416 */
1417 @Override
1418 public LocalDate minus(TemporalAmount amountToSubtract) {
1419 if (amountToSubtract instanceof Period) {
1420 Period periodToSubtract = (Period) amountToSubtract;
1421 return minusMonths(periodToSubtract.toTotalMonths()).minusDays(periodToSubtract.getDays());
1422 }
1423 Objects.requireNonNull(amountToSubtract, "amountToSubtract");
1424 return (LocalDate) amountToSubtract.subtractFrom(this);
1425 }
1426
1427 /**
1428 * Returns a copy of this date with the specified amount subtracted.
1429 * <p>
1430 * This returns a {@code LocalDate}, based on this one, with the amount
1431 * in terms of the unit subtracted. If it is not possible to subtract the amount,
1432 * because the unit is not supported or for some other reason, an exception is thrown.
1433 * <p>
1434 * This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
1435 * See that method for a full description of how addition, and thus subtraction, works.
1436 * <p>
1437 * This instance is immutable and unaffected by this method call.
1438 *
1439 * @param amountToSubtract the amount of the unit to subtract from the result, may be negative
1440 * @param unit the unit of the amount to subtract, not null
1441 * @return a {@code LocalDate} based on this date with the specified amount subtracted, not null
1442 * @throws DateTimeException if the subtraction cannot be made
1443 * @throws UnsupportedTemporalTypeException if the unit is not supported
1444 * @throws ArithmeticException if numeric overflow occurs
1445 */
1446 @Override
1447 public LocalDate minus(long amountToSubtract, TemporalUnit unit) {
1448 return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
1449 }
1450
1451 //-----------------------------------------------------------------------
1452 /**
1453 * Returns a copy of this {@code LocalDate} with the specified number of years subtracted.
1454 * <p>
1455 * This method subtracts the specified amount from the years field in three steps:
1456 * <ol>
1457 * <li>Subtract the input years from the year field</li>
1458 * <li>Check if the resulting date would be invalid</li>
1459 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1460 * </ol>
1461 * <p>
1462 * For example, 2008-02-29 (leap year) minus one year would result in the
1463 * invalid date 2007-02-29 (standard year). Instead of returning an invalid
1464 * result, the last valid day of the month, 2007-02-28, is selected instead.
1465 * <p>
1466 * This instance is immutable and unaffected by this method call.
1467 *
1468 * @param yearsToSubtract the years to subtract, may be negative
1469 * @return a {@code LocalDate} based on this date with the years subtracted, not null
1470 * @throws DateTimeException if the result exceeds the supported date range
1471 */
1472 public LocalDate minusYears(long yearsToSubtract) {
1473 return (yearsToSubtract == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-yearsToSubtract));
1474 }
1475
1476 /**
1477 * Returns a copy of this {@code LocalDate} with the specified number of months subtracted.
1478 * <p>
1479 * This method subtracts the specified amount from the months field in three steps:
1480 * <ol>
1481 * <li>Subtract the input months from the month-of-year field</li>
1482 * <li>Check if the resulting date would be invalid</li>
1483 * <li>Adjust the day-of-month to the last valid day if necessary</li>
1484 * </ol>
1485 * <p>
1486 * For example, 2007-03-31 minus one month would result in the invalid date
1487 * 2007-02-31. Instead of returning an invalid result, the last valid day
1488 * of the month, 2007-02-28, is selected instead.
1489 * <p>
1490 * This instance is immutable and unaffected by this method call.
1491 *
1492 * @param monthsToSubtract the months to subtract, may be negative
1493 * @return a {@code LocalDate} based on this date with the months subtracted, not null
1494 * @throws DateTimeException if the result exceeds the supported date range
1495 */
1496 public LocalDate minusMonths(long monthsToSubtract) {
1497 return (monthsToSubtract == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-monthsToSubtract));
1498 }
1499
1500 /**
1501 * Returns a copy of this {@code LocalDate} with the specified number of weeks subtracted.
1502 * <p>
1503 * This method subtracts the specified amount in weeks from the days field decrementing
1504 * the month and year fields as necessary to ensure the result remains valid.
1505 * The result is only invalid if the maximum/minimum year is exceeded.
1506 * <p>
1507 * For example, 2009-01-07 minus one week would result in 2008-12-31.
1508 * <p>
1509 * This instance is immutable and unaffected by this method call.
1510 *
1511 * @param weeksToSubtract the weeks to subtract, may be negative
1512 * @return a {@code LocalDate} based on this date with the weeks subtracted, not null
1513 * @throws DateTimeException if the result exceeds the supported date range
1514 */
1515 public LocalDate minusWeeks(long weeksToSubtract) {
1516 return (weeksToSubtract == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeksToSubtract));
1517 }
1518
1519 /**
1520 * Returns a copy of this {@code LocalDate} with the specified number of days subtracted.
1521 * <p>
1522 * This method subtracts the specified amount from the days field decrementing the
1523 * month and year fields as necessary to ensure the result remains valid.
1524 * The result is only invalid if the maximum/minimum year is exceeded.
1525 * <p>
1526 * For example, 2009-01-01 minus one day would result in 2008-12-31.
1527 * <p>
1528 * This instance is immutable and unaffected by this method call.
1529 *
1530 * @param daysToSubtract the days to subtract, may be negative
1531 * @return a {@code LocalDate} based on this date with the days subtracted, not null
1532 * @throws DateTimeException if the result exceeds the supported date range
1533 */
1534 public LocalDate minusDays(long daysToSubtract) {
1535 return (daysToSubtract == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-daysToSubtract));
1536 }
1537
1538 //-----------------------------------------------------------------------
1539 /**
1540 * Queries this date using the specified query.
1541 * <p>
1542 * This queries this date using the specified query strategy object.
1543 * The {@code TemporalQuery} object defines the logic to be used to
1544 * obtain the result. Read the documentation of the query to understand
1545 * what the result of this method will be.
1546 * <p>
1547 * The result of this method is obtained by invoking the
1548 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
1549 * specified query passing {@code this} as the argument.
1550 *
1551 * @param <R> the type of the result
1552 * @param query the query to invoke, not null
1553 * @return the query result, null may be returned (defined by the query)
1554 * @throws DateTimeException if unable to query (defined by the query)
1555 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
1556 */
1557 @SuppressWarnings("unchecked")
1558 @Override
1559 public <R> R query(TemporalQuery<R> query) {
1560 if (query == TemporalQueries.localDate()) {
1561 return (R) this;
1562 }
1563 return ChronoLocalDate.super.query(query);
1564 }
1565
1566 /**
1567 * Adjusts the specified temporal object to have the same date as this object.
1568 * <p>
1569 * This returns a temporal object of the same observable type as the input
1570 * with the date changed to be the same as this.
1571 * <p>
1572 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
1573 * passing {@link ChronoField#EPOCH_DAY} as the field.
1574 * <p>
1575 * In most cases, it is clearer to reverse the calling pattern by using
1576 * {@link Temporal#with(TemporalAdjuster)}:
1577 * <pre>
1578 * // these two lines are equivalent, but the second approach is recommended
1579 * temporal = thisLocalDate.adjustInto(temporal);
1580 * temporal = temporal.with(thisLocalDate);
1581 * </pre>
1582 * <p>
1583 * This instance is immutable and unaffected by this method call.
1584 *
1585 * @param temporal the target object to be adjusted, not null
1586 * @return the adjusted object, not null
1587 * @throws DateTimeException if unable to make the adjustment
1588 * @throws ArithmeticException if numeric overflow occurs
1589 */
1590 @Override // override for Javadoc
1591 public Temporal adjustInto(Temporal temporal) {
1592 return ChronoLocalDate.super.adjustInto(temporal);
1593 }
1594
1595 /**
1596 * Calculates the amount of time until another date in terms of the specified unit.
1597 * <p>
1598 * This calculates the amount of time between two {@code LocalDate}
1599 * objects in terms of a single {@code TemporalUnit}.
1600 * The start and end points are {@code this} and the specified date.
1601 * The result will be negative if the end is before the start.
1602 * The {@code Temporal} passed to this method is converted to a
1603 * {@code LocalDate} using {@link #from(TemporalAccessor)}.
1604 * For example, the amount in days between two dates can be calculated
1605 * using {@code startDate.until(endDate, DAYS)}.
1606 * <p>
1607 * The calculation returns a whole number, representing the number of
1608 * complete units between the two dates.
1609 * For example, the amount in months between 2012-06-15 and 2012-08-14
1610 * will only be one month as it is one day short of two months.
1611 * <p>
1612 * There are two equivalent ways of using this method.
1613 * The first is to invoke this method.
1614 * The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
1615 * <pre>
1616 * // these two lines are equivalent
1617 * amount = start.until(end, MONTHS);
1618 * amount = MONTHS.between(start, end);
1619 * </pre>
1620 * The choice should be made based on which makes the code more readable.
1621 * <p>
1622 * The calculation is implemented in this method for {@link ChronoUnit}.
1623 * The units {@code DAYS}, {@code WEEKS}, {@code MONTHS}, {@code YEARS},
1624 * {@code DECADES}, {@code CENTURIES}, {@code MILLENNIA} and {@code ERAS}
1625 * are supported. Other {@code ChronoUnit} values will throw an exception.
1626 * <p>
1627 * If the unit is not a {@code ChronoUnit}, then the result of this method
1628 * is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
1629 * passing {@code this} as the first argument and the converted input temporal
1630 * as the second argument.
1631 * <p>
1632 * This instance is immutable and unaffected by this method call.
1633 *
1634 * @param endExclusive the end date, exclusive, which is converted to a {@code LocalDate}, not null
1635 * @param unit the unit to measure the amount in, not null
1636 * @return the amount of time between this date and the end date
1637 * @throws DateTimeException if the amount cannot be calculated, or the end
1638 * temporal cannot be converted to a {@code LocalDate}
1639 * @throws UnsupportedTemporalTypeException if the unit is not supported
1640 * @throws ArithmeticException if numeric overflow occurs
1641 */
1642 @Override
1643 public long until(Temporal endExclusive, TemporalUnit unit) {
1644 LocalDate end = LocalDate.from(endExclusive);
1645 if (unit instanceof ChronoUnit) {
1646 switch ((ChronoUnit) unit) {
1647 case DAYS: return daysUntil(end);
1648 case WEEKS: return daysUntil(end) / 7;
1649 case MONTHS: return monthsUntil(end);
1650 case YEARS: return monthsUntil(end) / 12;
1651 case DECADES: return monthsUntil(end) / 120;
1652 case CENTURIES: return monthsUntil(end) / 1200;
1653 case MILLENNIA: return monthsUntil(end) / 12000;
1654 case ERAS: return end.getLong(ERA) - getLong(ERA);
1655 }
1656 throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1657 }
1658 return unit.between(this, end);
1659 }
1660
1661 long daysUntil(LocalDate end) {
1662 return end.toEpochDay() - toEpochDay(); // no overflow
1663 }
1664
1665 private long monthsUntil(LocalDate end) {
1666 long packed1 = getProlepticMonth() * 32L + getDayOfMonth(); // no overflow
1667 long packed2 = end.getProlepticMonth() * 32L + end.getDayOfMonth(); // no overflow
1668 return (packed2 - packed1) / 32;
1669 }
1670
1671 /**
1672 * Calculates the period between this date and another date as a {@code Period}.
1673 * <p>
1674 * This calculates the period between two dates in terms of years, months and days.
1675 * The start and end points are {@code this} and the specified date.
1676 * The result will be negative if the end is before the start.
1677 * The negative sign will be the same in each of year, month and day.
1678 * <p>
1679 * The calculation is performed using the ISO calendar system.
1680 * If necessary, the input date will be converted to ISO.
1681 * <p>
1682 * The start date is included, but the end date is not.
1683 * The period is calculated by removing complete months, then calculating
1684 * the remaining number of days, adjusting to ensure that both have the same sign.
1685 * The number of months is then normalized into years and months based on a 12 month year.
1686 * A month is considered to be complete if the end day-of-month is greater
1687 * than or equal to the start day-of-month.
1688 * For example, from {@code 2010-01-15} to {@code 2011-03-18} is "1 year, 2 months and 3 days".
1689 * <p>
1690 * There are two equivalent ways of using this method.
1691 * The first is to invoke this method.
1692 * The second is to use {@link Period#between(LocalDate, LocalDate)}:
1693 * <pre>
1694 * // these two lines are equivalent
1695 * period = start.until(end);
1696 * period = Period.between(start, end);
1697 * </pre>
1698 * The choice should be made based on which makes the code more readable.
1699 *
1700 * @param endDateExclusive the end date, exclusive, which may be in any chronology, not null
1701 * @return the period between this date and the end date, not null
1702 */
1703 @Override
1704 public Period until(ChronoLocalDate endDateExclusive) {
1705 LocalDate end = LocalDate.from(endDateExclusive);
1706 long totalMonths = end.getProlepticMonth() - this.getProlepticMonth(); // safe
1707 int days = end.day - this.day;
1708 if (totalMonths > 0 && days < 0) {
1709 totalMonths--;
1710 LocalDate calcDate = this.plusMonths(totalMonths);
1711 days = (int) (end.toEpochDay() - calcDate.toEpochDay()); // safe
1712 } else if (totalMonths < 0 && days > 0) {
1713 totalMonths++;
1714 days -= end.lengthOfMonth();
1715 }
1716 long years = totalMonths / 12; // safe
1717 int months = (int) (totalMonths % 12); // safe
1718 return Period.of(Math.toIntExact(years), months, days);
1719 }
1720
1721 /**
1722 * Returns a sequential ordered stream of dates. The returned stream starts from this date
1723 * (inclusive) and goes to {@code endExclusive} (exclusive) by an incremental step of 1 day.
1724 * <p>
1725 * This method is equivalent to {@code datesUntil(endExclusive, Period.ofDays(1))}.
1726 *
1727 * @param endExclusive the end date, exclusive, not null
1728 * @return a sequential {@code Stream} for the range of {@code LocalDate} values
1729 * @throws IllegalArgumentException if end date is before this date
1730 * @since 9
1731 */
1732 public Stream<LocalDate> datesUntil(LocalDate endExclusive) {
1733 long end = endExclusive.toEpochDay();
1734 long start = toEpochDay();
1735 if (end < start) {
1736 throw new IllegalArgumentException(endExclusive + " < " + this);
1737 }
1738 return LongStream.range(start, end).mapToObj(LocalDate::ofEpochDay);
1739 }
1740
1741 /**
1742 * Returns a sequential ordered stream of dates by given incremental step. The returned stream
1743 * starts from this date (inclusive) and goes to {@code endExclusive} (exclusive).
1744 * <p>
1745 * The n-th date which appears in the stream is equal to {@code this.plus(step.multipliedBy(n))}
1746 * (but the result of step multiplication never overflows). For example, if this date is
1747 * {@code 2015-01-31}, the end date is {@code 2015-05-01} and the step is 1 month, then the
1748 * stream contains {@code 2015-01-31}, {@code 2015-02-28}, {@code 2015-03-31}, and
1749 * {@code 2015-04-30}.
1750 *
1751 * @param endExclusive the end date, exclusive, not null
1752 * @param step the non-zero, non-negative {@code Period} which represents the step.
1753 * @return a sequential {@code Stream} for the range of {@code LocalDate} values
1754 * @throws IllegalArgumentException if step is zero, or {@code step.getDays()} and
1755 * {@code step.toTotalMonths()} have opposite sign, or end date is before this date
1756 * and step is positive, or end date is after this date and step is negative
1757 * @since 9
1758 */
1759 public Stream<LocalDate> datesUntil(LocalDate endExclusive, Period step) {
1760 if (step.isZero()) {
1761 throw new IllegalArgumentException("step is zero");
1762 }
1763 long end = endExclusive.toEpochDay();
1764 long start = toEpochDay();
1765 long until = end - start;
1766 long months = step.toTotalMonths();
1767 long days = step.getDays();
1768 if ((months < 0 && days > 0) || (months > 0 && days < 0)) {
1769 throw new IllegalArgumentException("period months and days are of opposite sign");
1770 }
1771 if (until == 0) {
1772 return Stream.empty();
1773 }
1774 int sign = months > 0 || days > 0 ? 1 : -1;
1775 if (sign < 0 ^ until < 0) {
1776 throw new IllegalArgumentException(endExclusive + (sign < 0 ? " > " : " < ") + this);
1777 }
1778 if (months == 0) {
1779 long steps = (until - sign) / days; // non-negative
1780 return LongStream.rangeClosed(0, steps).mapToObj(
1781 n -> LocalDate.ofEpochDay(start + n * days));
1782 }
1783 // 48699/1600 = 365.2425/12, no overflow, non-negative result
1784 long steps = until * 1600 / (months * 48699 + days * 1600) + 1;
1785 long addMonths = months * steps;
1786 long addDays = days * steps;
1787 long maxAddMonths = months > 0 ? MAX.getProlepticMonth() - getProlepticMonth()
1788 : getProlepticMonth() - MIN.getProlepticMonth();
1789 // adjust steps estimation
1790 if (addMonths * sign > maxAddMonths
1791 || (plusMonths(addMonths).toEpochDay() + addDays) * sign >= end * sign) {
1792 steps--;
1793 addMonths -= months;
1794 addDays -= days;
1795 if (addMonths * sign > maxAddMonths
1796 || (plusMonths(addMonths).toEpochDay() + addDays) * sign >= end * sign) {
1797 steps--;
1798 }
1799 }
1800 return LongStream.rangeClosed(0, steps).mapToObj(
1801 n -> this.plusMonths(months * n).plusDays(days * n));
1802 }
1803
1804 /**
1805 * Formats this date using the specified formatter.
1806 * <p>
1807 * This date will be passed to the formatter to produce a string.
1808 *
1809 * @param formatter the formatter to use, not null
1810 * @return the formatted date string, not null
1811 * @throws DateTimeException if an error occurs during printing
1812 */
1813 @Override // override for Javadoc and performance
1814 public String format(DateTimeFormatter formatter) {
1815 Objects.requireNonNull(formatter, "formatter");
1816 return formatter.format(this);
1817 }
1818
1819 //-----------------------------------------------------------------------
1820 /**
1821 * Combines this date with a time to create a {@code LocalDateTime}.
1822 * <p>
1823 * This returns a {@code LocalDateTime} formed from this date at the specified time.
1824 * All possible combinations of date and time are valid.
1825 *
1826 * @param time the time to combine with, not null
1827 * @return the local date-time formed from this date and the specified time, not null
1828 */
1829 @Override
1830 public LocalDateTime atTime(LocalTime time) {
1831 return LocalDateTime.of(this, time);
1832 }
1833
1834 /**
1835 * Combines this date with a time to create a {@code LocalDateTime}.
1836 * <p>
1837 * This returns a {@code LocalDateTime} formed from this date at the
1838 * specified hour and minute.
1839 * The seconds and nanosecond fields will be set to zero.
1840 * The individual time fields must be within their valid range.
1841 * All possible combinations of date and time are valid.
1842 *
1843 * @param hour the hour-of-day to use, from 0 to 23
1844 * @param minute the minute-of-hour to use, from 0 to 59
1845 * @return the local date-time formed from this date and the specified time, not null
1846 * @throws DateTimeException if the value of any field is out of range
1847 */
1848 public LocalDateTime atTime(int hour, int minute) {
1849 return atTime(LocalTime.of(hour, minute));
1850 }
1851
1852 /**
1853 * Combines this date with a time to create a {@code LocalDateTime}.
1854 * <p>
1855 * This returns a {@code LocalDateTime} formed from this date at the
1856 * specified hour, minute and second.
1857 * The nanosecond field will be set to zero.
1858 * The individual time fields must be within their valid range.
1859 * All possible combinations of date and time are valid.
1860 *
1861 * @param hour the hour-of-day to use, from 0 to 23
1862 * @param minute the minute-of-hour to use, from 0 to 59
1863 * @param second the second-of-minute to represent, from 0 to 59
1864 * @return the local date-time formed from this date and the specified time, not null
1865 * @throws DateTimeException if the value of any field is out of range
1866 */
1867 public LocalDateTime atTime(int hour, int minute, int second) {
1868 return atTime(LocalTime.of(hour, minute, second));
1869 }
1870
1871 /**
1872 * Combines this date with a time to create a {@code LocalDateTime}.
1873 * <p>
1874 * This returns a {@code LocalDateTime} formed from this date at the
1875 * specified hour, minute, second and nanosecond.
1876 * The individual time fields must be within their valid range.
1877 * All possible combinations of date and time are valid.
1878 *
1879 * @param hour the hour-of-day to use, from 0 to 23
1880 * @param minute the minute-of-hour to use, from 0 to 59
1881 * @param second the second-of-minute to represent, from 0 to 59
1882 * @param nanoOfSecond the nano-of-second to represent, from 0 to 999,999,999
1883 * @return the local date-time formed from this date and the specified time, not null
1884 * @throws DateTimeException if the value of any field is out of range
1885 */
1886 public LocalDateTime atTime(int hour, int minute, int second, int nanoOfSecond) {
1887 return atTime(LocalTime.of(hour, minute, second, nanoOfSecond));
1888 }
1889
1890 /**
1891 * Combines this date with an offset time to create an {@code OffsetDateTime}.
1892 * <p>
1893 * This returns an {@code OffsetDateTime} formed from this date at the specified time.
1894 * All possible combinations of date and time are valid.
1895 *
1896 * @param time the time to combine with, not null
1897 * @return the offset date-time formed from this date and the specified time, not null
1898 */
1899 public OffsetDateTime atTime(OffsetTime time) {
1900 return OffsetDateTime.of(LocalDateTime.of(this, time.toLocalTime()), time.getOffset());
1901 }
1902
1903 /**
1904 * Combines this date with the time of midnight to create a {@code LocalDateTime}
1905 * at the start of this date.
1906 * <p>
1907 * This returns a {@code LocalDateTime} formed from this date at the time of
1908 * midnight, 00:00, at the start of this date.
1909 *
1910 * @return the local date-time of midnight at the start of this date, not null
1911 */
1912 public LocalDateTime atStartOfDay() {
1913 return LocalDateTime.of(this, LocalTime.MIDNIGHT);
1914 }
1915
1916 /**
1917 * Returns a zoned date-time from this date at the earliest valid time according
1918 * to the rules in the time-zone.
1919 * <p>
1920 * Time-zone rules, such as daylight savings, mean that not every local date-time
1921 * is valid for the specified zone, thus the local date-time may not be midnight.
1922 * <p>
1923 * In most cases, there is only one valid offset for a local date-time.
1924 * In the case of an overlap, there are two valid offsets, and the earlier one is used,
1925 * corresponding to the first occurrence of midnight on the date.
1926 * In the case of a gap, the zoned date-time will represent the instant just after the gap.
1927 * <p>
1928 * If the zone ID is a {@link ZoneOffset}, then the result always has a time of midnight.
1929 * <p>
1930 * To convert to a specific time in a given time-zone call {@link #atTime(LocalTime)}
1931 * followed by {@link LocalDateTime#atZone(ZoneId)}.
1932 *
1933 * @param zone the zone ID to use, not null
1934 * @return the zoned date-time formed from this date and the earliest valid time for the zone, not null
1935 */
1936 public ZonedDateTime atStartOfDay(ZoneId zone) {
1937 Objects.requireNonNull(zone, "zone");
1938 // need to handle case where there is a gap from 11:30 to 00:30
1939 // standard ZDT factory would result in 01:00 rather than 00:30
1940 LocalDateTime ldt = atTime(LocalTime.MIDNIGHT);
1941 if (zone instanceof ZoneOffset == false) {
1942 ZoneRules rules = zone.getRules();
1943 ZoneOffsetTransition trans = rules.getTransition(ldt);
1944 if (trans != null && trans.isGap()) {
1945 ldt = trans.getDateTimeAfter();
1946 }
1947 }
1948 return ZonedDateTime.of(ldt, zone);
1949 }
1950
1951 //-----------------------------------------------------------------------
1952 @Override
1953 public long toEpochDay() {
1954 long y = year;
1955 long m = month;
1956 long total = 0;
1957 total += 365 * y;
1958 if (y >= 0) {
1959 total += (y + 3) / 4 - (y + 99) / 100 + (y + 399) / 400;
1960 } else {
1961 total -= y / -4 - y / -100 + y / -400;
1962 }
1963 total += ((367 * m - 362) / 12);
1964 total += day - 1;
1965 if (m > 2) {
1966 total--;
1967 if (isLeapYear() == false) {
1968 total--;
1969 }
1970 }
1971 return total - DAYS_0000_TO_1970;
1972 }
1973
1974 /**
1975 * Converts this {@code LocalDate} to the number of seconds since the epoch
1976 * of 1970-01-01T00:00:00Z.
1977 * <p>
1978 * This combines this local date with the specified time and
1979 * offset to calculate the epoch-second value, which is the
1980 * number of elapsed seconds from 1970-01-01T00:00:00Z.
1981 * Instants on the time-line after the epoch are positive, earlier
1982 * are negative.
1983 *
1984 * @param time the local time, not null
1985 * @param offset the zone offset, not null
1986 * @return the number of seconds since the epoch of 1970-01-01T00:00:00Z, may be negative
1987 * @since 9
1988 */
1989 public long toEpochSecond(LocalTime time, ZoneOffset offset) {
1990 Objects.requireNonNull(time, "time");
1991 Objects.requireNonNull(offset, "offset");
1992 long secs = toEpochDay() * SECONDS_PER_DAY + time.toSecondOfDay();
1993 secs -= offset.getTotalSeconds();
1994 return secs;
1995 }
1996
1997 //-----------------------------------------------------------------------
1998 /**
1999 * Compares this date to another date.
2000 * <p>
2001 * The comparison is primarily based on the date, from earliest to latest.
2002 * It is "consistent with equals", as defined by {@link Comparable}.
2003 * <p>
2004 * If all the dates being compared are instances of {@code LocalDate},
2005 * then the comparison will be entirely based on the date.
2006 * If some dates being compared are in different chronologies, then the
2007 * chronology is also considered, see {@link java.time.chrono.ChronoLocalDate#compareTo}.
2008 *
2009 * @param other the other date to compare to, not null
2010 * @return the comparator value, negative if less, positive if greater
2011 */
2012 @Override // override for Javadoc and performance
2013 public int compareTo(ChronoLocalDate other) {
2014 if (other instanceof LocalDate) {
2015 return compareTo0((LocalDate) other);
2016 }
2017 return ChronoLocalDate.super.compareTo(other);
2018 }
2019
2020 int compareTo0(LocalDate otherDate) {
2021 int cmp = (year - otherDate.year);
2022 if (cmp == 0) {
2023 cmp = (month - otherDate.month);
2024 if (cmp == 0) {
2025 cmp = (day - otherDate.day);
2026 }
2027 }
2028 return cmp;
2029 }
2030
2031 /**
2032 * Checks if this date is after the specified date.
2033 * <p>
2034 * This checks to see if this date represents a point on the
2035 * local time-line after the other date.
2036 * <pre>
2037 * LocalDate a = LocalDate.of(2012, 6, 30);
2038 * LocalDate b = LocalDate.of(2012, 7, 1);
2039 * a.isAfter(b) == false
2040 * a.isAfter(a) == false
2041 * b.isAfter(a) == true
2042 * </pre>
2043 * <p>
2044 * This method only considers the position of the two dates on the local time-line.
2045 * It does not take into account the chronology, or calendar system.
2046 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)},
2047 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2048 *
2049 * @param other the other date to compare to, not null
2050 * @return true if this date is after the specified date
2051 */
2052 @Override // override for Javadoc and performance
2053 public boolean isAfter(ChronoLocalDate other) {
2054 if (other instanceof LocalDate) {
2055 return compareTo0((LocalDate) other) > 0;
2056 }
2057 return ChronoLocalDate.super.isAfter(other);
2058 }
2059
2060 /**
2061 * Checks if this date is before the specified date.
2062 * <p>
2063 * This checks to see if this date represents a point on the
2064 * local time-line before the other date.
2065 * <pre>
2066 * LocalDate a = LocalDate.of(2012, 6, 30);
2067 * LocalDate b = LocalDate.of(2012, 7, 1);
2068 * a.isBefore(b) == true
2069 * a.isBefore(a) == false
2070 * b.isBefore(a) == false
2071 * </pre>
2072 * <p>
2073 * This method only considers the position of the two dates on the local time-line.
2074 * It does not take into account the chronology, or calendar system.
2075 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)},
2076 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2077 *
2078 * @param other the other date to compare to, not null
2079 * @return true if this date is before the specified date
2080 */
2081 @Override // override for Javadoc and performance
2082 public boolean isBefore(ChronoLocalDate other) {
2083 if (other instanceof LocalDate) {
2084 return compareTo0((LocalDate) other) < 0;
2085 }
2086 return ChronoLocalDate.super.isBefore(other);
2087 }
2088
2089 /**
2090 * Checks if this date is equal to the specified date.
2091 * <p>
2092 * This checks to see if this date represents the same point on the
2093 * local time-line as the other date.
2094 * <pre>
2095 * LocalDate a = LocalDate.of(2012, 6, 30);
2096 * LocalDate b = LocalDate.of(2012, 7, 1);
2097 * a.isEqual(b) == false
2098 * a.isEqual(a) == true
2099 * b.isEqual(a) == false
2100 * </pre>
2101 * <p>
2102 * This method only considers the position of the two dates on the local time-line.
2103 * It does not take into account the chronology, or calendar system.
2104 * This is different from the comparison in {@link #compareTo(ChronoLocalDate)}
2105 * but is the same approach as {@link ChronoLocalDate#timeLineOrder()}.
2106 *
2107 * @param other the other date to compare to, not null
2108 * @return true if this date is equal to the specified date
2109 */
2110 @Override // override for Javadoc and performance
2111 public boolean isEqual(ChronoLocalDate other) {
2112 if (other instanceof LocalDate) {
2113 return compareTo0((LocalDate) other) == 0;
2114 }
2115 return ChronoLocalDate.super.isEqual(other);
2116 }
2117
2118 //-----------------------------------------------------------------------
2119 /**
2120 * Checks if this date is equal to another date.
2121 * <p>
2122 * Compares this {@code LocalDate} with another ensuring that the date is the same.
2123 * <p>
2124 * Only objects of type {@code LocalDate} are compared, other types return false.
2125 * To compare the dates of two {@code TemporalAccessor} instances, including dates
2126 * in two different chronologies, use {@link ChronoField#EPOCH_DAY} as a comparator.
2127 *
2128 * @param obj the object to check, null returns false
2129 * @return true if this is equal to the other date
2130 */
2131 @Override
2132 public boolean equals(Object obj) {
2133 if (this == obj) {
2134 return true;
2135 }
2136 if (obj instanceof LocalDate) {
2137 return compareTo0((LocalDate) obj) == 0;
2138 }
2139 return false;
2140 }
2141
2142 /**
2143 * A hash code for this date.
2144 *
2145 * @return a suitable hash code
2146 */
2147 @Override
2148 public int hashCode() {
2149 int yearValue = year;
2150 int monthValue = month;
2151 int dayValue = day;
2152 return (yearValue & 0xFFFFF800) ^ ((yearValue << 11) + (monthValue << 6) + (dayValue));
2153 }
2154
2155 //-----------------------------------------------------------------------
2156 /**
2157 * Outputs this date as a {@code String}, such as {@code 2007-12-03}.
2158 * <p>
2159 * The output will be in the ISO-8601 format {@code uuuu-MM-dd}.
2160 *
2161 * @return a string representation of this date, not null
2162 */
2163 @Override
2164 public String toString() {
2165 int yearValue = year;
2166 int monthValue = month;
2167 int dayValue = day;
2168 int absYear = Math.abs(yearValue);
2169 StringBuilder buf = new StringBuilder(10);
2170 if (absYear < 1000) {
2171 if (yearValue < 0) {
2172 buf.append(yearValue - 10000).deleteCharAt(1);
2173 } else {
2174 buf.append(yearValue + 10000).deleteCharAt(0);
2175 }
2176 } else {
2177 if (yearValue > 9999) {
2178 buf.append('+');
2179 }
2180 buf.append(yearValue);
2181 }
2182 return buf.append(monthValue < 10 ? "-0" : "-")
2183 .append(monthValue)
2184 .append(dayValue < 10 ? "-0" : "-")
2185 .append(dayValue)
2186 .toString();
2187 }
2188
2189 //-----------------------------------------------------------------------
2190 /**
2191 * Writes the object using a
2192 * <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
2193 * @serialData
2194 * <pre>
2195 * out.writeByte(3); // identifies a LocalDate
2196 * out.writeInt(year);
2197 * out.writeByte(month);
2198 * out.writeByte(day);
2199 * </pre>
2200 *
2201 * @return the instance of {@code Ser}, not null
2202 */
2203 private Object writeReplace() {
2204 return new Ser(Ser.LOCAL_DATE_TYPE, this);
2205 }
2206
2207 /**
2208 * Defend against malicious streams.
2209 *
2210 * @param s the stream to read
2211 * @throws InvalidObjectException always
2212 */
2213 private void readObject(ObjectInputStream s) throws InvalidObjectException {
2214 throw new InvalidObjectException("Deserialization via serialization delegate");
2215 }
2216
2217 void writeExternal(DataOutput out) throws IOException {
2218 out.writeInt(year);
2219 out.writeByte(month);
2220 out.writeByte(day);
2221 }
2222
2223 static LocalDate readExternal(DataInput in) throws IOException {
2224 int year = in.readInt();
2225 int month = in.readByte();
2226 int dayOfMonth = in.readByte();
2227 return LocalDate.of(year, month, dayOfMonth);
2228 }
2229
2230 }