1 /*
2 * Copyright (c) 2012, 2013, 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 *
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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.chrono;
63
64 import static java.time.temporal.ChronoField.EPOCH_DAY;
65 import static java.time.temporal.ChronoField.NANO_OF_DAY;
66 import static java.time.temporal.ChronoUnit.FOREVER;
67 import static java.time.temporal.ChronoUnit.NANOS;
68
69 import java.io.Serializable;
70 import java.time.DateTimeException;
71 import java.time.Instant;
72 import java.time.LocalDateTime;
73 import java.time.LocalTime;
74 import java.time.ZoneId;
75 import java.time.ZoneOffset;
76 import java.time.format.DateTimeFormatter;
77 import java.time.temporal.ChronoField;
78 import java.time.temporal.ChronoUnit;
79 import java.time.temporal.Temporal;
80 import java.time.temporal.TemporalAccessor;
81 import java.time.temporal.TemporalAdjuster;
82 import java.time.temporal.TemporalAmount;
83 import java.time.temporal.TemporalField;
84 import java.time.temporal.TemporalQueries;
85 import java.time.temporal.TemporalQuery;
86 import java.time.temporal.TemporalUnit;
87 import java.time.zone.ZoneRules;
88 import java.util.Comparator;
89 import java.util.Objects;
90
91 /**
92 * A date-time without a time-zone in an arbitrary chronology, intended
93 * for advanced globalization use cases.
94 * <p>
95 * <b>Most applications should declare method signatures, fields and variables
96 * as {@link LocalDateTime}, not this interface.</b>
97 * <p>
98 * A {@code ChronoLocalDateTime} is the abstract representation of a local date-time
99 * where the {@code Chronology chronology}, or calendar system, is pluggable.
100 * The date-time is defined in terms of fields expressed by {@link TemporalField},
101 * where most common implementations are defined in {@link ChronoField}.
102 * The chronology defines how the calendar system operates and the meaning of
103 * the standard fields.
104 *
105 * <h3>When to use this interface</h3>
106 * The design of the API encourages the use of {@code LocalDateTime} rather than this
107 * interface, even in the case where the application needs to deal with multiple
108 * calendar systems. The rationale for this is explored in detail in {@link ChronoLocalDate}.
109 * <p>
110 * Ensure that the discussion in {@code ChronoLocalDate} has been read and understood
111 * before using this interface.
112 *
113 * @implSpec
114 * This interface must be implemented with care to ensure other classes operate correctly.
115 * All implementations that can be instantiated must be final, immutable and thread-safe.
116 * Subclasses should be Serializable wherever possible.
117 *
118 * @param <D> the concrete type for the date of this date-time
119 * @since 1.8
120 */
121 public interface ChronoLocalDateTime<D extends ChronoLocalDate>
122 extends Temporal, TemporalAdjuster, Comparable<ChronoLocalDateTime<?>> {
123
124 /**
125 * Gets a comparator that compares {@code ChronoLocalDateTime} in
126 * time-line order ignoring the chronology.
127 * <p>
128 * This comparator differs from the comparison in {@link #compareTo} in that it
129 * only compares the underlying date-time and not the chronology.
130 * This allows dates in different calendar systems to be compared based
131 * on the position of the date-time on the local time-line.
132 * The underlying comparison is equivalent to comparing the epoch-day and nano-of-day.
133 *
134 * @return a comparator that compares in time-line order ignoring the chronology
135 * @see #isAfter
136 * @see #isBefore
137 * @see #isEqual
138 */
139 static Comparator<ChronoLocalDateTime<?>> timeLineOrder() {
140 return (Comparator<ChronoLocalDateTime<? extends ChronoLocalDate>> & Serializable) (dateTime1, dateTime2) -> {
141 int cmp = Long.compare(dateTime1.toLocalDate().toEpochDay(), dateTime2.toLocalDate().toEpochDay());
142 if (cmp == 0) {
143 cmp = Long.compare(dateTime1.toLocalTime().toNanoOfDay(), dateTime2.toLocalTime().toNanoOfDay());
144 }
145 return cmp;
146 };
147 }
148
149 //-----------------------------------------------------------------------
150 /**
151 * Obtains an instance of {@code ChronoLocalDateTime} from a temporal object.
152 * <p>
153 * This obtains a local date-time based on the specified temporal.
154 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
155 * which this factory converts to an instance of {@code ChronoLocalDateTime}.
156 * <p>
157 * The conversion extracts and combines the chronology and the date-time
158 * from the temporal object. The behavior is equivalent to using
159 * {@link Chronology#localDateTime(TemporalAccessor)} with the extracted chronology.
160 * Implementations are permitted to perform optimizations such as accessing
161 * those fields that are equivalent to the relevant objects.
162 * <p>
163 * This method matches the signature of the functional interface {@link TemporalQuery}
164 * allowing it to be used as a query via method reference, {@code ChronoLocalDateTime::from}.
165 *
166 * @param temporal the temporal object to convert, not null
167 * @return the date-time, not null
168 * @throws DateTimeException if unable to convert to a {@code ChronoLocalDateTime}
169 * @see Chronology#localDateTime(TemporalAccessor)
170 */
171 static ChronoLocalDateTime<?> from(TemporalAccessor temporal) {
172 if (temporal instanceof ChronoLocalDateTime) {
173 return (ChronoLocalDateTime<?>) temporal;
174 }
175 Objects.requireNonNull(temporal, "temporal");
176 Chronology chrono = temporal.query(TemporalQueries.chronology());
177 if (chrono == null) {
178 throw new DateTimeException("Unable to obtain ChronoLocalDateTime from TemporalAccessor: " + temporal.getClass());
179 }
180 return chrono.localDateTime(temporal);
181 }
182
183 //-----------------------------------------------------------------------
184 /**
185 * Gets the chronology of this date-time.
186 * <p>
187 * The {@code Chronology} represents the calendar system in use.
188 * The era and other fields in {@link ChronoField} are defined by the chronology.
189 *
190 * @return the chronology, not null
191 */
192 default Chronology getChronology() {
193 return toLocalDate().getChronology();
194 }
195
196 /**
197 * Gets the local date part of this date-time.
198 * <p>
199 * This returns a local date with the same year, month and day
200 * as this date-time.
201 *
202 * @return the date part of this date-time, not null
203 */
204 D toLocalDate() ;
205
206 /**
207 * Gets the local time part of this date-time.
208 * <p>
209 * This returns a local time with the same hour, minute, second and
210 * nanosecond as this date-time.
211 *
212 * @return the time part of this date-time, not null
213 */
214 LocalTime toLocalTime();
215
216 /**
217 * Checks if the specified field is supported.
218 * <p>
219 * This checks if the specified field can be queried on this date-time.
220 * If false, then calling the {@link #range(TemporalField) range},
221 * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
222 * methods will throw an exception.
223 * <p>
224 * The set of supported fields is defined by the chronology and normally includes
225 * all {@code ChronoField} date and time fields.
226 * <p>
227 * If the field is not a {@code ChronoField}, then the result of this method
228 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
229 * passing {@code this} as the argument.
230 * Whether the field is supported is determined by the field.
231 *
232 * @param field the field to check, null returns false
233 * @return true if the field can be queried, false if not
234 */
235 @Override
236 boolean isSupported(TemporalField field);
237
238 /**
239 * Checks if the specified unit is supported.
240 * <p>
241 * This checks if the specified unit can be added to or subtracted from this date-time.
242 * If false, then calling the {@link #plus(long, TemporalUnit)} and
243 * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
244 * <p>
245 * The set of supported units is defined by the chronology and normally includes
246 * all {@code ChronoUnit} units except {@code FOREVER}.
247 * <p>
248 * If the unit is not a {@code ChronoUnit}, then the result of this method
249 * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
250 * passing {@code this} as the argument.
251 * Whether the unit is supported is determined by the unit.
252 *
253 * @param unit the unit to check, null returns false
254 * @return true if the unit can be added/subtracted, false if not
255 */
256 @Override
257 default boolean isSupported(TemporalUnit unit) {
258 if (unit instanceof ChronoUnit) {
259 return unit != FOREVER;
260 }
261 return unit != null && unit.isSupportedBy(this);
262 }
263
264 //-----------------------------------------------------------------------
265 // override for covariant return type
266 /**
267 * {@inheritDoc}
268 * @throws DateTimeException {@inheritDoc}
269 * @throws ArithmeticException {@inheritDoc}
270 */
271 @Override
272 default ChronoLocalDateTime<D> with(TemporalAdjuster adjuster) {
273 return ChronoLocalDateTimeImpl.ensureValid(getChronology(), Temporal.super.with(adjuster));
274 }
275
276 /**
277 * {@inheritDoc}
278 * @throws DateTimeException {@inheritDoc}
279 * @throws ArithmeticException {@inheritDoc}
280 */
281 @Override
282 ChronoLocalDateTime<D> with(TemporalField field, long newValue);
283
284 /**
285 * {@inheritDoc}
286 * @throws DateTimeException {@inheritDoc}
287 * @throws ArithmeticException {@inheritDoc}
288 */
289 @Override
290 default ChronoLocalDateTime<D> plus(TemporalAmount amount) {
291 return ChronoLocalDateTimeImpl.ensureValid(getChronology(), Temporal.super.plus(amount));
292 }
293
294 /**
295 * {@inheritDoc}
296 * @throws DateTimeException {@inheritDoc}
297 * @throws ArithmeticException {@inheritDoc}
298 */
299 @Override
300 ChronoLocalDateTime<D> plus(long amountToAdd, TemporalUnit unit);
301
302 /**
303 * {@inheritDoc}
304 * @throws DateTimeException {@inheritDoc}
305 * @throws ArithmeticException {@inheritDoc}
306 */
307 @Override
308 default ChronoLocalDateTime<D> minus(TemporalAmount amount) {
309 return ChronoLocalDateTimeImpl.ensureValid(getChronology(), Temporal.super.minus(amount));
310 }
311
312 /**
313 * {@inheritDoc}
314 * @throws DateTimeException {@inheritDoc}
315 * @throws ArithmeticException {@inheritDoc}
316 */
317 @Override
318 default ChronoLocalDateTime<D> minus(long amountToSubtract, TemporalUnit unit) {
319 return ChronoLocalDateTimeImpl.ensureValid(getChronology(), Temporal.super.minus(amountToSubtract, unit));
320 }
321
322 //-----------------------------------------------------------------------
323 /**
324 * Queries this date-time using the specified query.
325 * <p>
326 * This queries this date-time using the specified query strategy object.
327 * The {@code TemporalQuery} object defines the logic to be used to
328 * obtain the result. Read the documentation of the query to understand
329 * what the result of this method will be.
330 * <p>
331 * The result of this method is obtained by invoking the
332 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
333 * specified query passing {@code this} as the argument.
334 *
335 * @param <R> the type of the result
336 * @param query the query to invoke, not null
337 * @return the query result, null may be returned (defined by the query)
338 * @throws DateTimeException if unable to query (defined by the query)
339 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
340 */
341 @SuppressWarnings("unchecked")
342 @Override
343 default <R> R query(TemporalQuery<R> query) {
344 if (query == TemporalQueries.zoneId() || query == TemporalQueries.zone() || query == TemporalQueries.offset()) {
345 return null;
346 } else if (query == TemporalQueries.localTime()) {
347 return (R) toLocalTime();
348 } else if (query == TemporalQueries.chronology()) {
349 return (R) getChronology();
350 } else if (query == TemporalQueries.precision()) {
351 return (R) NANOS;
352 }
353 // inline TemporalAccessor.super.query(query) as an optimization
354 // non-JDK classes are not permitted to make this optimization
355 return query.queryFrom(this);
356 }
357
358 /**
359 * Adjusts the specified temporal object to have the same date and time as this object.
360 * <p>
361 * This returns a temporal object of the same observable type as the input
362 * with the date and time changed to be the same as this.
363 * <p>
364 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
365 * twice, passing {@link ChronoField#EPOCH_DAY} and
366 * {@link ChronoField#NANO_OF_DAY} as the fields.
367 * <p>
368 * In most cases, it is clearer to reverse the calling pattern by using
369 * {@link Temporal#with(TemporalAdjuster)}:
370 * <pre>
371 * // these two lines are equivalent, but the second approach is recommended
372 * temporal = thisLocalDateTime.adjustInto(temporal);
373 * temporal = temporal.with(thisLocalDateTime);
374 * </pre>
375 * <p>
376 * This instance is immutable and unaffected by this method call.
377 *
378 * @param temporal the target object to be adjusted, not null
379 * @return the adjusted object, not null
380 * @throws DateTimeException if unable to make the adjustment
381 * @throws ArithmeticException if numeric overflow occurs
382 */
383 @Override
384 default Temporal adjustInto(Temporal temporal) {
385 return temporal
386 .with(EPOCH_DAY, toLocalDate().toEpochDay())
387 .with(NANO_OF_DAY, toLocalTime().toNanoOfDay());
388 }
389
390 /**
391 * Formats this date-time using the specified formatter.
392 * <p>
393 * This date-time will be passed to the formatter to produce a string.
394 * <p>
395 * The default implementation must behave as follows:
396 * <pre>
397 * return formatter.format(this);
398 * </pre>
399 *
400 * @param formatter the formatter to use, not null
401 * @return the formatted date-time string, not null
402 * @throws DateTimeException if an error occurs during printing
403 */
404 default String format(DateTimeFormatter formatter) {
405 Objects.requireNonNull(formatter, "formatter");
406 return formatter.format(this);
407 }
408
409 //-----------------------------------------------------------------------
410 /**
411 * Combines this time with a time-zone to create a {@code ChronoZonedDateTime}.
412 * <p>
413 * This returns a {@code ChronoZonedDateTime} formed from this date-time at the
414 * specified time-zone. The result will match this date-time as closely as possible.
415 * Time-zone rules, such as daylight savings, mean that not every local date-time
416 * is valid for the specified zone, thus the local date-time may be adjusted.
417 * <p>
418 * The local date-time is resolved to a single instant on the time-line.
419 * This is achieved by finding a valid offset from UTC/Greenwich for the local
420 * date-time as defined by the {@link ZoneRules rules} of the zone ID.
421 *<p>
422 * In most cases, there is only one valid offset for a local date-time.
423 * In the case of an overlap, where clocks are set back, there are two valid offsets.
424 * This method uses the earlier offset typically corresponding to "summer".
425 * <p>
426 * In the case of a gap, where clocks jump forward, there is no valid offset.
427 * Instead, the local date-time is adjusted to be later by the length of the gap.
428 * For a typical one hour daylight savings change, the local date-time will be
429 * moved one hour later into the offset typically corresponding to "summer".
430 * <p>
431 * To obtain the later offset during an overlap, call
432 * {@link ChronoZonedDateTime#withLaterOffsetAtOverlap()} on the result of this method.
433 *
434 * @param zone the time-zone to use, not null
435 * @return the zoned date-time formed from this date-time, not null
436 */
437 ChronoZonedDateTime<D> atZone(ZoneId zone);
438
439 //-----------------------------------------------------------------------
440 /**
441 * Converts this date-time to an {@code Instant}.
442 * <p>
443 * This combines this local date-time and the specified offset to form
444 * an {@code Instant}.
445 * <p>
446 * This default implementation calculates from the epoch-day of the date and the
447 * second-of-day of the time.
448 *
449 * @param offset the offset to use for the conversion, not null
450 * @return an {@code Instant} representing the same instant, not null
451 */
452 default Instant toInstant(ZoneOffset offset) {
453 return Instant.ofEpochSecond(toEpochSecond(offset), toLocalTime().getNano());
454 }
455
456 /**
457 * Converts this date-time to the number of seconds from the epoch
458 * of 1970-01-01T00:00:00Z.
459 * <p>
460 * This combines this local date-time and the specified offset to calculate the
461 * epoch-second value, which is the number of elapsed seconds from 1970-01-01T00:00:00Z.
462 * Instants on the time-line after the epoch are positive, earlier are negative.
463 * <p>
464 * This default implementation calculates from the epoch-day of the date and the
465 * second-of-day of the time.
466 *
467 * @param offset the offset to use for the conversion, not null
468 * @return the number of seconds from the epoch of 1970-01-01T00:00:00Z
469 */
470 default long toEpochSecond(ZoneOffset offset) {
471 Objects.requireNonNull(offset, "offset");
472 long epochDay = toLocalDate().toEpochDay();
473 long secs = epochDay * 86400 + toLocalTime().toSecondOfDay();
474 secs -= offset.getTotalSeconds();
475 return secs;
476 }
477
478 //-----------------------------------------------------------------------
479 /**
480 * Compares this date-time to another date-time, including the chronology.
481 * <p>
482 * The comparison is based first on the underlying time-line date-time, then
483 * on the chronology.
484 * It is "consistent with equals", as defined by {@link Comparable}.
485 * <p>
486 * For example, the following is the comparator order:
487 * <ol>
488 * <li>{@code 2012-12-03T12:00 (ISO)}</li>
489 * <li>{@code 2012-12-04T12:00 (ISO)}</li>
490 * <li>{@code 2555-12-04T12:00 (ThaiBuddhist)}</li>
491 * <li>{@code 2012-12-05T12:00 (ISO)}</li>
492 * </ol>
493 * Values #2 and #3 represent the same date-time on the time-line.
494 * When two values represent the same date-time, the chronology ID is compared to distinguish them.
495 * This step is needed to make the ordering "consistent with equals".
496 * <p>
497 * If all the date-time objects being compared are in the same chronology, then the
498 * additional chronology stage is not required and only the local date-time is used.
499 * <p>
500 * This default implementation performs the comparison defined above.
501 *
502 * @param other the other date-time to compare to, not null
503 * @return the comparator value, negative if less, positive if greater
504 */
505 @Override
506 default int compareTo(ChronoLocalDateTime<?> other) {
507 int cmp = toLocalDate().compareTo(other.toLocalDate());
508 if (cmp == 0) {
509 cmp = toLocalTime().compareTo(other.toLocalTime());
510 if (cmp == 0) {
511 cmp = getChronology().compareTo(other.getChronology());
512 }
513 }
514 return cmp;
515 }
516
517 /**
518 * Checks if this date-time is after the specified date-time ignoring the chronology.
519 * <p>
520 * This method differs from the comparison in {@link #compareTo} in that it
521 * only compares the underlying date-time and not the chronology.
522 * This allows dates in different calendar systems to be compared based
523 * on the time-line position.
524 * <p>
525 * This default implementation performs the comparison based on the epoch-day
526 * and nano-of-day.
527 *
528 * @param other the other date-time to compare to, not null
529 * @return true if this is after the specified date-time
530 */
531 default boolean isAfter(ChronoLocalDateTime<?> other) {
532 long thisEpDay = this.toLocalDate().toEpochDay();
533 long otherEpDay = other.toLocalDate().toEpochDay();
534 return thisEpDay > otherEpDay ||
535 (thisEpDay == otherEpDay && this.toLocalTime().toNanoOfDay() > other.toLocalTime().toNanoOfDay());
536 }
537
538 /**
539 * Checks if this date-time is before the specified date-time ignoring the chronology.
540 * <p>
541 * This method differs from the comparison in {@link #compareTo} in that it
542 * only compares the underlying date-time and not the chronology.
543 * This allows dates in different calendar systems to be compared based
544 * on the time-line position.
545 * <p>
546 * This default implementation performs the comparison based on the epoch-day
547 * and nano-of-day.
548 *
549 * @param other the other date-time to compare to, not null
550 * @return true if this is before the specified date-time
551 */
552 default boolean isBefore(ChronoLocalDateTime<?> other) {
553 long thisEpDay = this.toLocalDate().toEpochDay();
554 long otherEpDay = other.toLocalDate().toEpochDay();
555 return thisEpDay < otherEpDay ||
556 (thisEpDay == otherEpDay && this.toLocalTime().toNanoOfDay() < other.toLocalTime().toNanoOfDay());
557 }
558
559 /**
560 * Checks if this date-time is equal to the specified date-time ignoring the chronology.
561 * <p>
562 * This method differs from the comparison in {@link #compareTo} in that it
563 * only compares the underlying date and time and not the chronology.
564 * This allows date-times in different calendar systems to be compared based
565 * on the time-line position.
566 * <p>
567 * This default implementation performs the comparison based on the epoch-day
568 * and nano-of-day.
569 *
570 * @param other the other date-time to compare to, not null
571 * @return true if the underlying date-time is equal to the specified date-time on the timeline
572 */
573 default boolean isEqual(ChronoLocalDateTime<?> other) {
574 // Do the time check first, it is cheaper than computing EPOCH day.
575 return this.toLocalTime().toNanoOfDay() == other.toLocalTime().toNanoOfDay() &&
576 this.toLocalDate().toEpochDay() == other.toLocalDate().toEpochDay();
577 }
578
579 /**
580 * Checks if this date-time is equal to another date-time, including the chronology.
581 * <p>
582 * Compares this date-time with another ensuring that the date-time and chronology are the same.
583 *
584 * @param obj the object to check, null returns false
585 * @return true if this is equal to the other date
586 */
587 @Override
588 boolean equals(Object obj);
589
590 /**
591 * A hash code for this date-time.
592 *
593 * @return a suitable hash code
594 */
595 @Override
596 int hashCode();
597
598 //-----------------------------------------------------------------------
599 /**
600 * Outputs this date-time as a {@code String}.
601 * <p>
602 * The output will include the full local date-time.
603 *
604 * @return a string representation of this date-time, not null
605 */
606 @Override
607 String toString();
608
609 }