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.INSTANT_SECONDS;
65 import static java.time.temporal.ChronoField.OFFSET_SECONDS;
66 import static java.time.temporal.ChronoUnit.FOREVER;
67 import static java.time.temporal.ChronoUnit.NANOS;
68
69 import java.time.DateTimeException;
70 import java.time.Instant;
71 import java.time.LocalTime;
72 import java.time.ZoneId;
73 import java.time.ZoneOffset;
74 import java.time.ZonedDateTime;
75 import java.time.format.DateTimeFormatter;
76 import java.time.temporal.ChronoField;
77 import java.time.temporal.ChronoUnit;
78 import java.time.temporal.Temporal;
79 import java.time.temporal.TemporalAccessor;
80 import java.time.temporal.TemporalAdjuster;
81 import java.time.temporal.TemporalAmount;
82 import java.time.temporal.TemporalField;
83 import java.time.temporal.TemporalQueries;
84 import java.time.temporal.TemporalQuery;
85 import java.time.temporal.TemporalUnit;
86 import java.time.temporal.UnsupportedTemporalTypeException;
87 import java.time.temporal.ValueRange;
88 import java.util.Comparator;
89 import java.util.Objects;
90
91 /**
92 * A date-time with a time-zone in an arbitrary chronology,
93 * intended for advanced globalization use cases.
94 * <p>
95 * <b>Most applications should declare method signatures, fields and variables
96 * as {@link ZonedDateTime}, not this interface.</b>
97 * <p>
98 * A {@code ChronoZonedDateTime} is the abstract representation of an offset 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 ZonedDateTime} 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 ChronoZonedDateTime<D extends ChronoLocalDate>
122 extends Temporal, Comparable<ChronoZonedDateTime<?>> {
123
124 /**
125 * Gets a comparator that compares {@code ChronoZonedDateTime} 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 instant 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 instant time-line.
132 * The underlying comparison is equivalent to comparing the epoch-second and nano-of-second.
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<ChronoZonedDateTime<?>> timeLineOrder() {
140 return AbstractChronology.INSTANT_ORDER;
141 }
142
143 //-----------------------------------------------------------------------
144 /**
145 * Obtains an instance of {@code ChronoZonedDateTime} from a temporal object.
146 * <p>
147 * This creates a zoned date-time based on the specified temporal.
148 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
149 * which this factory converts to an instance of {@code ChronoZonedDateTime}.
150 * <p>
151 * The conversion extracts and combines the chronology, date, time and zone
152 * from the temporal object. The behavior is equivalent to using
153 * {@link Chronology#zonedDateTime(TemporalAccessor)} with the extracted chronology.
154 * Implementations are permitted to perform optimizations such as accessing
155 * those fields that are equivalent to the relevant objects.
156 * <p>
157 * This method matches the signature of the functional interface {@link TemporalQuery}
158 * allowing it to be used as a query via method reference, {@code ChronoZonedDateTime::from}.
159 *
160 * @param temporal the temporal object to convert, not null
161 * @return the date-time, not null
162 * @throws DateTimeException if unable to convert to a {@code ChronoZonedDateTime}
163 * @see Chronology#zonedDateTime(TemporalAccessor)
164 */
165 static ChronoZonedDateTime<?> from(TemporalAccessor temporal) {
166 if (temporal instanceof ChronoZonedDateTime) {
167 return (ChronoZonedDateTime<?>) temporal;
168 }
169 Objects.requireNonNull(temporal, "temporal");
170 Chronology chrono = temporal.query(TemporalQueries.chronology());
171 if (chrono == null) {
172 throw new DateTimeException("Unable to obtain ChronoZonedDateTime from TemporalAccessor: " + temporal.getClass());
173 }
174 return chrono.zonedDateTime(temporal);
175 }
176
177 //-----------------------------------------------------------------------
178 @Override
179 default ValueRange range(TemporalField field) {
180 if (field instanceof ChronoField) {
181 if (field == INSTANT_SECONDS || field == OFFSET_SECONDS) {
182 return field.range();
183 }
184 return toLocalDateTime().range(field);
185 }
186 return field.rangeRefinedBy(this);
187 }
188
189 @Override
190 default int get(TemporalField field) {
191 if (field instanceof ChronoField) {
192 switch ((ChronoField) field) {
193 case INSTANT_SECONDS:
194 throw new UnsupportedTemporalTypeException("Invalid field 'InstantSeconds' for get() method, use getLong() instead");
195 case OFFSET_SECONDS:
196 return getOffset().getTotalSeconds();
197 }
198 return toLocalDateTime().get(field);
199 }
200 return Temporal.super.get(field);
201 }
202
203 @Override
204 default long getLong(TemporalField field) {
205 if (field instanceof ChronoField) {
206 switch ((ChronoField) field) {
207 case INSTANT_SECONDS: return toEpochSecond();
208 case OFFSET_SECONDS: return getOffset().getTotalSeconds();
209 }
210 return toLocalDateTime().getLong(field);
211 }
212 return field.getFrom(this);
213 }
214
215 /**
216 * Gets the local date part of this date-time.
217 * <p>
218 * This returns a local date with the same year, month and day
219 * as this date-time.
220 *
221 * @return the date part of this date-time, not null
222 */
223 default D toLocalDate() {
224 return toLocalDateTime().toLocalDate();
225 }
226
227 /**
228 * Gets the local time part of this date-time.
229 * <p>
230 * This returns a local time with the same hour, minute, second and
231 * nanosecond as this date-time.
232 *
233 * @return the time part of this date-time, not null
234 */
235 default LocalTime toLocalTime() {
236 return toLocalDateTime().toLocalTime();
237 }
238
239 /**
240 * Gets the local date-time part of this date-time.
241 * <p>
242 * This returns a local date with the same year, month and day
243 * as this date-time.
244 *
245 * @return the local date-time part of this date-time, not null
246 */
247 ChronoLocalDateTime<D> toLocalDateTime();
248
249 /**
250 * Gets the chronology of this date-time.
251 * <p>
252 * The {@code Chronology} represents the calendar system in use.
253 * The era and other fields in {@link ChronoField} are defined by the chronology.
254 *
255 * @return the chronology, not null
256 */
257 default Chronology getChronology() {
258 return toLocalDate().getChronology();
259 }
260
261 /**
262 * Gets the zone offset, such as '+01:00'.
263 * <p>
264 * This is the offset of the local date-time from UTC/Greenwich.
265 *
266 * @return the zone offset, not null
267 */
268 ZoneOffset getOffset();
269
270 /**
271 * Gets the zone ID, such as 'Europe/Paris'.
272 * <p>
273 * This returns the stored time-zone id used to determine the time-zone rules.
274 *
275 * @return the zone ID, not null
276 */
277 ZoneId getZone();
278
279 //-----------------------------------------------------------------------
280 /**
281 * Returns a copy of this date-time changing the zone offset to the
282 * earlier of the two valid offsets at a local time-line overlap.
283 * <p>
284 * This method only has any effect when the local time-line overlaps, such as
285 * at an autumn daylight savings cutover. In this scenario, there are two
286 * valid offsets for the local date-time. Calling this method will return
287 * a zoned date-time with the earlier of the two selected.
288 * <p>
289 * If this method is called when it is not an overlap, {@code this}
290 * is returned.
291 * <p>
292 * This instance is immutable and unaffected by this method call.
293 *
294 * @return a {@code ChronoZonedDateTime} based on this date-time with the earlier offset, not null
295 * @throws DateTimeException if no rules can be found for the zone
296 * @throws DateTimeException if no rules are valid for this date-time
297 */
298 ChronoZonedDateTime<D> withEarlierOffsetAtOverlap();
299
300 /**
301 * Returns a copy of this date-time changing the zone offset to the
302 * later of the two valid offsets at a local time-line overlap.
303 * <p>
304 * This method only has any effect when the local time-line overlaps, such as
305 * at an autumn daylight savings cutover. In this scenario, there are two
306 * valid offsets for the local date-time. Calling this method will return
307 * a zoned date-time with the later of the two selected.
308 * <p>
309 * If this method is called when it is not an overlap, {@code this}
310 * is returned.
311 * <p>
312 * This instance is immutable and unaffected by this method call.
313 *
314 * @return a {@code ChronoZonedDateTime} based on this date-time with the later offset, not null
315 * @throws DateTimeException if no rules can be found for the zone
316 * @throws DateTimeException if no rules are valid for this date-time
317 */
318 ChronoZonedDateTime<D> withLaterOffsetAtOverlap();
319
320 /**
321 * Returns a copy of this date-time with a different time-zone,
322 * retaining the local date-time if possible.
323 * <p>
324 * This method changes the time-zone and retains the local date-time.
325 * The local date-time is only changed if it is invalid for the new zone.
326 * <p>
327 * To change the zone and adjust the local date-time,
328 * use {@link #withZoneSameInstant(ZoneId)}.
329 * <p>
330 * This instance is immutable and unaffected by this method call.
331 *
332 * @param zone the time-zone to change to, not null
333 * @return a {@code ChronoZonedDateTime} based on this date-time with the requested zone, not null
334 */
335 ChronoZonedDateTime<D> withZoneSameLocal(ZoneId zone);
336
337 /**
338 * Returns a copy of this date-time with a different time-zone,
339 * retaining the instant.
340 * <p>
341 * This method changes the time-zone and retains the instant.
342 * This normally results in a change to the local date-time.
343 * <p>
344 * This method is based on retaining the same instant, thus gaps and overlaps
345 * in the local time-line have no effect on the result.
346 * <p>
347 * To change the offset while keeping the local time,
348 * use {@link #withZoneSameLocal(ZoneId)}.
349 *
350 * @param zone the time-zone to change to, not null
351 * @return a {@code ChronoZonedDateTime} based on this date-time with the requested zone, not null
352 * @throws DateTimeException if the result exceeds the supported date range
353 */
354 ChronoZonedDateTime<D> withZoneSameInstant(ZoneId zone);
355
356 /**
357 * Checks if the specified field is supported.
358 * <p>
359 * This checks if the specified field can be queried on this date-time.
360 * If false, then calling the {@link #range(TemporalField) range},
361 * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
362 * methods will throw an exception.
363 * <p>
364 * The set of supported fields is defined by the chronology and normally includes
365 * all {@code ChronoField} fields.
366 * <p>
367 * If the field is not a {@code ChronoField}, then the result of this method
368 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
369 * passing {@code this} as the argument.
370 * Whether the field is supported is determined by the field.
371 *
372 * @param field the field to check, null returns false
373 * @return true if the field can be queried, false if not
374 */
375 @Override
376 boolean isSupported(TemporalField field);
377
378 /**
379 * Checks if the specified unit is supported.
380 * <p>
381 * This checks if the specified unit can be added to or subtracted from this date-time.
382 * If false, then calling the {@link #plus(long, TemporalUnit)} and
383 * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
384 * <p>
385 * The set of supported units is defined by the chronology and normally includes
386 * all {@code ChronoUnit} units except {@code FOREVER}.
387 * <p>
388 * If the unit is not a {@code ChronoUnit}, then the result of this method
389 * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
390 * passing {@code this} as the argument.
391 * Whether the unit is supported is determined by the unit.
392 *
393 * @param unit the unit to check, null returns false
394 * @return true if the unit can be added/subtracted, false if not
395 */
396 @Override
397 default boolean isSupported(TemporalUnit unit) {
398 if (unit instanceof ChronoUnit) {
399 return unit != FOREVER;
400 }
401 return unit != null && unit.isSupportedBy(this);
402 }
403
404 //-----------------------------------------------------------------------
405 // override for covariant return type
406 /**
407 * {@inheritDoc}
408 * @throws DateTimeException {@inheritDoc}
409 * @throws ArithmeticException {@inheritDoc}
410 */
411 @Override
412 default ChronoZonedDateTime<D> with(TemporalAdjuster adjuster) {
413 return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.with(adjuster));
414 }
415
416 /**
417 * {@inheritDoc}
418 * @throws DateTimeException {@inheritDoc}
419 * @throws ArithmeticException {@inheritDoc}
420 */
421 @Override
422 ChronoZonedDateTime<D> with(TemporalField field, long newValue);
423
424 /**
425 * {@inheritDoc}
426 * @throws DateTimeException {@inheritDoc}
427 * @throws ArithmeticException {@inheritDoc}
428 */
429 @Override
430 default ChronoZonedDateTime<D> plus(TemporalAmount amount) {
431 return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.plus(amount));
432 }
433
434 /**
435 * {@inheritDoc}
436 * @throws DateTimeException {@inheritDoc}
437 * @throws ArithmeticException {@inheritDoc}
438 */
439 @Override
440 ChronoZonedDateTime<D> plus(long amountToAdd, TemporalUnit unit);
441
442 /**
443 * {@inheritDoc}
444 * @throws DateTimeException {@inheritDoc}
445 * @throws ArithmeticException {@inheritDoc}
446 */
447 @Override
448 default ChronoZonedDateTime<D> minus(TemporalAmount amount) {
449 return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.minus(amount));
450 }
451
452 /**
453 * {@inheritDoc}
454 * @throws DateTimeException {@inheritDoc}
455 * @throws ArithmeticException {@inheritDoc}
456 */
457 @Override
458 default ChronoZonedDateTime<D> minus(long amountToSubtract, TemporalUnit unit) {
459 return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.minus(amountToSubtract, unit));
460 }
461
462 //-----------------------------------------------------------------------
463 /**
464 * Queries this date-time using the specified query.
465 * <p>
466 * This queries this date-time using the specified query strategy object.
467 * The {@code TemporalQuery} object defines the logic to be used to
468 * obtain the result. Read the documentation of the query to understand
469 * what the result of this method will be.
470 * <p>
471 * The result of this method is obtained by invoking the
472 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
473 * specified query passing {@code this} as the argument.
474 *
475 * @param <R> the type of the result
476 * @param query the query to invoke, not null
477 * @return the query result, null may be returned (defined by the query)
478 * @throws DateTimeException if unable to query (defined by the query)
479 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
480 */
481 @SuppressWarnings("unchecked")
482 @Override
483 default <R> R query(TemporalQuery<R> query) {
484 if (query == TemporalQueries.zone() || query == TemporalQueries.zoneId()) {
485 return (R) getZone();
486 } else if (query == TemporalQueries.offset()) {
487 return (R) getOffset();
488 } else if (query == TemporalQueries.localTime()) {
489 return (R) toLocalTime();
490 } else if (query == TemporalQueries.chronology()) {
491 return (R) getChronology();
492 } else if (query == TemporalQueries.precision()) {
493 return (R) NANOS;
494 }
495 // inline TemporalAccessor.super.query(query) as an optimization
496 // non-JDK classes are not permitted to make this optimization
497 return query.queryFrom(this);
498 }
499
500 /**
501 * Formats this date-time using the specified formatter.
502 * <p>
503 * This date-time will be passed to the formatter to produce a string.
504 * <p>
505 * The default implementation must behave as follows:
506 * <pre>
507 * return formatter.format(this);
508 * </pre>
509 *
510 * @param formatter the formatter to use, not null
511 * @return the formatted date-time string, not null
512 * @throws DateTimeException if an error occurs during printing
513 */
514 default String format(DateTimeFormatter formatter) {
515 Objects.requireNonNull(formatter, "formatter");
516 return formatter.format(this);
517 }
518
519 //-----------------------------------------------------------------------
520 /**
521 * Converts this date-time to an {@code Instant}.
522 * <p>
523 * This returns an {@code Instant} representing the same point on the
524 * time-line as this date-time. The calculation combines the
525 * {@linkplain #toLocalDateTime() local date-time} and
526 * {@linkplain #getOffset() offset}.
527 *
528 * @return an {@code Instant} representing the same instant, not null
529 */
530 default Instant toInstant() {
531 return Instant.ofEpochSecond(toEpochSecond(), toLocalTime().getNano());
532 }
533
534 /**
535 * Converts this date-time to the number of seconds from the epoch
536 * of 1970-01-01T00:00:00Z.
537 * <p>
538 * This uses the {@linkplain #toLocalDateTime() local date-time} and
539 * {@linkplain #getOffset() offset} to calculate the epoch-second value,
540 * which is the number of elapsed seconds from 1970-01-01T00:00:00Z.
541 * Instants on the time-line after the epoch are positive, earlier are negative.
542 *
543 * @return the number of seconds from the epoch of 1970-01-01T00:00:00Z
544 */
545 default long toEpochSecond() {
546 long epochDay = toLocalDate().toEpochDay();
547 long secs = epochDay * 86400 + toLocalTime().toSecondOfDay();
548 secs -= getOffset().getTotalSeconds();
549 return secs;
550 }
551
552 //-----------------------------------------------------------------------
553 /**
554 * Compares this date-time to another date-time, including the chronology.
555 * <p>
556 * The comparison is based first on the instant, then on the local date-time,
557 * then on the zone ID, then on the chronology.
558 * It is "consistent with equals", as defined by {@link Comparable}.
559 * <p>
560 * If all the date-time objects being compared are in the same chronology, then the
561 * additional chronology stage is not required.
562 * <p>
563 * This default implementation performs the comparison defined above.
564 *
565 * @param other the other date-time to compare to, not null
566 * @return the comparator value, negative if less, positive if greater
567 */
568 @Override
569 default int compareTo(ChronoZonedDateTime<?> other) {
570 int cmp = Long.compare(toEpochSecond(), other.toEpochSecond());
571 if (cmp == 0) {
572 cmp = toLocalTime().getNano() - other.toLocalTime().getNano();
573 if (cmp == 0) {
574 cmp = toLocalDateTime().compareTo(other.toLocalDateTime());
575 if (cmp == 0) {
576 cmp = getZone().getId().compareTo(other.getZone().getId());
577 if (cmp == 0) {
578 cmp = getChronology().compareTo(other.getChronology());
579 }
580 }
581 }
582 }
583 return cmp;
584 }
585
586 /**
587 * Checks if the instant of this date-time is before that of the specified date-time.
588 * <p>
589 * This method differs from the comparison in {@link #compareTo} in that it
590 * only compares the instant of the date-time. This is equivalent to using
591 * {@code dateTime1.toInstant().isBefore(dateTime2.toInstant());}.
592 * <p>
593 * This default implementation performs the comparison based on the epoch-second
594 * and nano-of-second.
595 *
596 * @param other the other date-time to compare to, not null
597 * @return true if this point is before the specified date-time
598 */
599 default boolean isBefore(ChronoZonedDateTime<?> other) {
600 long thisEpochSec = toEpochSecond();
601 long otherEpochSec = other.toEpochSecond();
602 return thisEpochSec < otherEpochSec ||
603 (thisEpochSec == otherEpochSec && toLocalTime().getNano() < other.toLocalTime().getNano());
604 }
605
606 /**
607 * Checks if the instant of this date-time is after that of the specified date-time.
608 * <p>
609 * This method differs from the comparison in {@link #compareTo} in that it
610 * only compares the instant of the date-time. This is equivalent to using
611 * {@code dateTime1.toInstant().isAfter(dateTime2.toInstant());}.
612 * <p>
613 * This default implementation performs the comparison based on the epoch-second
614 * and nano-of-second.
615 *
616 * @param other the other date-time to compare to, not null
617 * @return true if this is after the specified date-time
618 */
619 default boolean isAfter(ChronoZonedDateTime<?> other) {
620 long thisEpochSec = toEpochSecond();
621 long otherEpochSec = other.toEpochSecond();
622 return thisEpochSec > otherEpochSec ||
623 (thisEpochSec == otherEpochSec && toLocalTime().getNano() > other.toLocalTime().getNano());
624 }
625
626 /**
627 * Checks if the instant of this date-time is equal to that of the specified date-time.
628 * <p>
629 * This method differs from the comparison in {@link #compareTo} and {@link #equals}
630 * in that it only compares the instant of the date-time. This is equivalent to using
631 * {@code dateTime1.toInstant().equals(dateTime2.toInstant());}.
632 * <p>
633 * This default implementation performs the comparison based on the epoch-second
634 * and nano-of-second.
635 *
636 * @param other the other date-time to compare to, not null
637 * @return true if the instant equals the instant of the specified date-time
638 */
639 default boolean isEqual(ChronoZonedDateTime<?> other) {
640 return toEpochSecond() == other.toEpochSecond() &&
641 toLocalTime().getNano() == other.toLocalTime().getNano();
642 }
643
644 //-----------------------------------------------------------------------
645 /**
646 * Checks if this date-time is equal to another date-time.
647 * <p>
648 * The comparison is based on the offset date-time and the zone.
649 * To compare for the same instant on the time-line, use {@link #compareTo}.
650 * Only objects of type {@code ChronoZonedDateTime} are compared, other types return false.
651 *
652 * @param obj the object to check, null returns false
653 * @return true if this is equal to the other date-time
654 */
655 @Override
656 boolean equals(Object obj);
657
658 /**
659 * A hash code for this date-time.
660 *
661 * @return a suitable hash code
662 */
663 @Override
664 int hashCode();
665
666 //-----------------------------------------------------------------------
667 /**
668 * Outputs this date-time as a {@code String}.
669 * <p>
670 * The output will include the full zoned date-time.
671 *
672 * @return a string representation of this date-time, not null
673 */
674 @Override
675 String toString();
676
677 }