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