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2 * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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14 * version 2 for more details (a copy is included in the LICENSE file that
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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 *
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40 *    this list of conditions and the following disclaimer.
41 *
42 *  * Redistributions in binary form must reproduce the above copyright notice,
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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
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60 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61 */
62package java.time;
63
64import static java.time.LocalTime.NANOS_PER_HOUR;
65import static java.time.LocalTime.NANOS_PER_MINUTE;
66import static java.time.LocalTime.NANOS_PER_SECOND;
67import static java.time.LocalTime.SECONDS_PER_DAY;
68import static java.time.temporal.ChronoField.NANO_OF_DAY;
69import static java.time.temporal.ChronoField.OFFSET_SECONDS;
70import static java.time.temporal.ChronoUnit.NANOS;
71
72import java.io.IOException;
73import java.io.ObjectInput;
74import java.io.ObjectOutput;
75import java.io.InvalidObjectException;
76import java.io.ObjectInputStream;
77import java.io.Serializable;
78import java.time.format.DateTimeFormatter;
79import java.time.format.DateTimeParseException;
80import java.time.temporal.ChronoField;
81import java.time.temporal.ChronoUnit;
82import java.time.temporal.Temporal;
83import java.time.temporal.TemporalAccessor;
84import java.time.temporal.TemporalAdjuster;
85import java.time.temporal.TemporalAmount;
86import java.time.temporal.TemporalField;
87import java.time.temporal.TemporalQueries;
88import java.time.temporal.TemporalQuery;
89import java.time.temporal.TemporalUnit;
90import java.time.temporal.UnsupportedTemporalTypeException;
91import java.time.temporal.ValueRange;
92import java.time.zone.ZoneRules;
93import java.util.Objects;
94
95// Android-changed: removed ValueBased paragraph.
96/**
97 * A time with an offset from UTC/Greenwich in the ISO-8601 calendar system,
98 * such as {@code 10:15:30+01:00}.
99 * <p>
100 * {@code OffsetTime} is an immutable date-time object that represents a time, often
101 * viewed as hour-minute-second-offset.
102 * This class stores all time fields, to a precision of nanoseconds,
103 * as well as a zone offset.
104 * For example, the value "13:45.30.123456789+02:00" can be stored
105 * in an {@code OffsetTime}.
106 *
107 * @implSpec
108 * This class is immutable and thread-safe.
109 *
110 * @since 1.8
111 */
112public final class OffsetTime
113        implements Temporal, TemporalAdjuster, Comparable<OffsetTime>, Serializable {
114
115    /**
116     * The minimum supported {@code OffsetTime}, '00:00:00+18:00'.
117     * This is the time of midnight at the start of the day in the maximum offset
118     * (larger offsets are earlier on the time-line).
119     * This combines {@link LocalTime#MIN} and {@link ZoneOffset#MAX}.
120     * This could be used by an application as a "far past" date.
121     */
122    public static final OffsetTime MIN = LocalTime.MIN.atOffset(ZoneOffset.MAX);
123    /**
124     * The maximum supported {@code OffsetTime}, '23:59:59.999999999-18:00'.
125     * This is the time just before midnight at the end of the day in the minimum offset
126     * (larger negative offsets are later on the time-line).
127     * This combines {@link LocalTime#MAX} and {@link ZoneOffset#MIN}.
128     * This could be used by an application as a "far future" date.
129     */
130    public static final OffsetTime MAX = LocalTime.MAX.atOffset(ZoneOffset.MIN);
131
132    /**
133     * Serialization version.
134     */
135    private static final long serialVersionUID = 7264499704384272492L;
136
137    /**
138     * The local date-time.
139     */
140    private final LocalTime time;
141    /**
142     * The offset from UTC/Greenwich.
143     */
144    private final ZoneOffset offset;
145
146    //-----------------------------------------------------------------------
147    /**
148     * Obtains the current time from the system clock in the default time-zone.
149     * <p>
150     * This will query the {@link Clock#systemDefaultZone() system clock} in the default
151     * time-zone to obtain the current time.
152     * The offset will be calculated from the time-zone in the clock.
153     * <p>
154     * Using this method will prevent the ability to use an alternate clock for testing
155     * because the clock is hard-coded.
156     *
157     * @return the current time using the system clock and default time-zone, not null
158     */
159    public static OffsetTime now() {
160        return now(Clock.systemDefaultZone());
161    }
162
163    /**
164     * Obtains the current time from the system clock in the specified time-zone.
165     * <p>
166     * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current time.
167     * Specifying the time-zone avoids dependence on the default time-zone.
168     * The offset will be calculated from the specified time-zone.
169     * <p>
170     * Using this method will prevent the ability to use an alternate clock for testing
171     * because the clock is hard-coded.
172     *
173     * @param zone  the zone ID to use, not null
174     * @return the current time using the system clock, not null
175     */
176    public static OffsetTime now(ZoneId zone) {
177        return now(Clock.system(zone));
178    }
179
180    /**
181     * Obtains the current time from the specified clock.
182     * <p>
183     * This will query the specified clock to obtain the current time.
184     * The offset will be calculated from the time-zone in the clock.
185     * <p>
186     * Using this method allows the use of an alternate clock for testing.
187     * The alternate clock may be introduced using {@link Clock dependency injection}.
188     *
189     * @param clock  the clock to use, not null
190     * @return the current time, not null
191     */
192    public static OffsetTime now(Clock clock) {
193        Objects.requireNonNull(clock, "clock");
194        final Instant now = clock.instant();  // called once
195        return ofInstant(now, clock.getZone().getRules().getOffset(now));
196    }
197
198    //-----------------------------------------------------------------------
199    /**
200     * Obtains an instance of {@code OffsetTime} from a local time and an offset.
201     *
202     * @param time  the local time, not null
203     * @param offset  the zone offset, not null
204     * @return the offset time, not null
205     */
206    public static OffsetTime of(LocalTime time, ZoneOffset offset) {
207        return new OffsetTime(time, offset);
208    }
209
210    /**
211     * Obtains an instance of {@code OffsetTime} from an hour, minute, second and nanosecond.
212     * <p>
213     * This creates an offset time with the four specified fields.
214     * <p>
215     * This method exists primarily for writing test cases.
216     * Non test-code will typically use other methods to create an offset time.
217     * {@code LocalTime} has two additional convenience variants of the
218     * equivalent factory method taking fewer arguments.
219     * They are not provided here to reduce the footprint of the API.
220     *
221     * @param hour  the hour-of-day to represent, from 0 to 23
222     * @param minute  the minute-of-hour to represent, from 0 to 59
223     * @param second  the second-of-minute to represent, from 0 to 59
224     * @param nanoOfSecond  the nano-of-second to represent, from 0 to 999,999,999
225     * @param offset  the zone offset, not null
226     * @return the offset time, not null
227     * @throws DateTimeException if the value of any field is out of range
228     */
229    public static OffsetTime of(int hour, int minute, int second, int nanoOfSecond, ZoneOffset offset) {
230        return new OffsetTime(LocalTime.of(hour, minute, second, nanoOfSecond), offset);
231    }
232
233    //-----------------------------------------------------------------------
234    /**
235     * Obtains an instance of {@code OffsetTime} from an {@code Instant} and zone ID.
236     * <p>
237     * This creates an offset time with the same instant as that specified.
238     * Finding the offset from UTC/Greenwich is simple as there is only one valid
239     * offset for each instant.
240     * <p>
241     * The date component of the instant is dropped during the conversion.
242     * This means that the conversion can never fail due to the instant being
243     * out of the valid range of dates.
244     *
245     * @param instant  the instant to create the time from, not null
246     * @param zone  the time-zone, which may be an offset, not null
247     * @return the offset time, not null
248     */
249    public static OffsetTime ofInstant(Instant instant, ZoneId zone) {
250        Objects.requireNonNull(instant, "instant");
251        Objects.requireNonNull(zone, "zone");
252        ZoneRules rules = zone.getRules();
253        ZoneOffset offset = rules.getOffset(instant);
254        long localSecond = instant.getEpochSecond() + offset.getTotalSeconds();  // overflow caught later
255        int secsOfDay = (int) Math.floorMod(localSecond, SECONDS_PER_DAY);
256        LocalTime time = LocalTime.ofNanoOfDay(secsOfDay * NANOS_PER_SECOND + instant.getNano());
257        return new OffsetTime(time, offset);
258    }
259
260    //-----------------------------------------------------------------------
261    /**
262     * Obtains an instance of {@code OffsetTime} from a temporal object.
263     * <p>
264     * This obtains an offset time based on the specified temporal.
265     * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
266     * which this factory converts to an instance of {@code OffsetTime}.
267     * <p>
268     * The conversion extracts and combines the {@code ZoneOffset} and the
269     * {@code LocalTime} from the temporal object.
270     * Implementations are permitted to perform optimizations such as accessing
271     * those fields that are equivalent to the relevant objects.
272     * <p>
273     * This method matches the signature of the functional interface {@link TemporalQuery}
274     * allowing it to be used as a query via method reference, {@code OffsetTime::from}.
275     *
276     * @param temporal  the temporal object to convert, not null
277     * @return the offset time, not null
278     * @throws DateTimeException if unable to convert to an {@code OffsetTime}
279     */
280    public static OffsetTime from(TemporalAccessor temporal) {
281        if (temporal instanceof OffsetTime) {
282            return (OffsetTime) temporal;
283        }
284        try {
285            LocalTime time = LocalTime.from(temporal);
286            ZoneOffset offset = ZoneOffset.from(temporal);
287            return new OffsetTime(time, offset);
288        } catch (DateTimeException ex) {
289            throw new DateTimeException("Unable to obtain OffsetTime from TemporalAccessor: " +
290                    temporal + " of type " + temporal.getClass().getName(), ex);
291        }
292    }
293
294    //-----------------------------------------------------------------------
295    /**
296     * Obtains an instance of {@code OffsetTime} from a text string such as {@code 10:15:30+01:00}.
297     * <p>
298     * The string must represent a valid time and is parsed using
299     * {@link java.time.format.DateTimeFormatter#ISO_OFFSET_TIME}.
300     *
301     * @param text  the text to parse such as "10:15:30+01:00", not null
302     * @return the parsed local time, not null
303     * @throws DateTimeParseException if the text cannot be parsed
304     */
305    public static OffsetTime parse(CharSequence text) {
306        return parse(text, DateTimeFormatter.ISO_OFFSET_TIME);
307    }
308
309    /**
310     * Obtains an instance of {@code OffsetTime} from a text string using a specific formatter.
311     * <p>
312     * The text is parsed using the formatter, returning a time.
313     *
314     * @param text  the text to parse, not null
315     * @param formatter  the formatter to use, not null
316     * @return the parsed offset time, not null
317     * @throws DateTimeParseException if the text cannot be parsed
318     */
319    public static OffsetTime parse(CharSequence text, DateTimeFormatter formatter) {
320        Objects.requireNonNull(formatter, "formatter");
321        return formatter.parse(text, OffsetTime::from);
322    }
323
324    //-----------------------------------------------------------------------
325    /**
326     * Constructor.
327     *
328     * @param time  the local time, not null
329     * @param offset  the zone offset, not null
330     */
331    private OffsetTime(LocalTime time, ZoneOffset offset) {
332        this.time = Objects.requireNonNull(time, "time");
333        this.offset = Objects.requireNonNull(offset, "offset");
334    }
335
336    /**
337     * Returns a new time based on this one, returning {@code this} where possible.
338     *
339     * @param time  the time to create with, not null
340     * @param offset  the zone offset to create with, not null
341     */
342    private OffsetTime with(LocalTime time, ZoneOffset offset) {
343        if (this.time == time && this.offset.equals(offset)) {
344            return this;
345        }
346        return new OffsetTime(time, offset);
347    }
348
349    //-----------------------------------------------------------------------
350    /**
351     * Checks if the specified field is supported.
352     * <p>
353     * This checks if this time can be queried for the specified field.
354     * If false, then calling the {@link #range(TemporalField) range},
355     * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
356     * methods will throw an exception.
357     * <p>
358     * If the field is a {@link ChronoField} then the query is implemented here.
359     * The supported fields are:
360     * <ul>
361     * <li>{@code NANO_OF_SECOND}
362     * <li>{@code NANO_OF_DAY}
363     * <li>{@code MICRO_OF_SECOND}
364     * <li>{@code MICRO_OF_DAY}
365     * <li>{@code MILLI_OF_SECOND}
366     * <li>{@code MILLI_OF_DAY}
367     * <li>{@code SECOND_OF_MINUTE}
368     * <li>{@code SECOND_OF_DAY}
369     * <li>{@code MINUTE_OF_HOUR}
370     * <li>{@code MINUTE_OF_DAY}
371     * <li>{@code HOUR_OF_AMPM}
372     * <li>{@code CLOCK_HOUR_OF_AMPM}
373     * <li>{@code HOUR_OF_DAY}
374     * <li>{@code CLOCK_HOUR_OF_DAY}
375     * <li>{@code AMPM_OF_DAY}
376     * <li>{@code OFFSET_SECONDS}
377     * </ul>
378     * All other {@code ChronoField} instances will return false.
379     * <p>
380     * If the field is not a {@code ChronoField}, then the result of this method
381     * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
382     * passing {@code this} as the argument.
383     * Whether the field is supported is determined by the field.
384     *
385     * @param field  the field to check, null returns false
386     * @return true if the field is supported on this time, false if not
387     */
388    @Override
389    public boolean isSupported(TemporalField field) {
390        if (field instanceof ChronoField) {
391            return field.isTimeBased() || field == OFFSET_SECONDS;
392        }
393        return field != null && field.isSupportedBy(this);
394    }
395
396    /**
397     * Checks if the specified unit is supported.
398     * <p>
399     * This checks if the specified unit can be added to, or subtracted from, this offset-time.
400     * If false, then calling the {@link #plus(long, TemporalUnit)} and
401     * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
402     * <p>
403     * If the unit is a {@link ChronoUnit} then the query is implemented here.
404     * The supported units are:
405     * <ul>
406     * <li>{@code NANOS}
407     * <li>{@code MICROS}
408     * <li>{@code MILLIS}
409     * <li>{@code SECONDS}
410     * <li>{@code MINUTES}
411     * <li>{@code HOURS}
412     * <li>{@code HALF_DAYS}
413     * </ul>
414     * All other {@code ChronoUnit} instances will return false.
415     * <p>
416     * If the unit is not a {@code ChronoUnit}, then the result of this method
417     * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
418     * passing {@code this} as the argument.
419     * Whether the unit is supported is determined by the unit.
420     *
421     * @param unit  the unit to check, null returns false
422     * @return true if the unit can be added/subtracted, false if not
423     */
424    @Override  // override for Javadoc
425    public boolean isSupported(TemporalUnit unit) {
426        if (unit instanceof ChronoUnit) {
427            return unit.isTimeBased();
428        }
429        return unit != null && unit.isSupportedBy(this);
430    }
431
432    //-----------------------------------------------------------------------
433    /**
434     * Gets the range of valid values for the specified field.
435     * <p>
436     * The range object expresses the minimum and maximum valid values for a field.
437     * This time is used to enhance the accuracy of the returned range.
438     * If it is not possible to return the range, because the field is not supported
439     * or for some other reason, an exception is thrown.
440     * <p>
441     * If the field is a {@link ChronoField} then the query is implemented here.
442     * The {@link #isSupported(TemporalField) supported fields} will return
443     * appropriate range instances.
444     * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
445     * <p>
446     * If the field is not a {@code ChronoField}, then the result of this method
447     * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
448     * passing {@code this} as the argument.
449     * Whether the range can be obtained is determined by the field.
450     *
451     * @param field  the field to query the range for, not null
452     * @return the range of valid values for the field, not null
453     * @throws DateTimeException if the range for the field cannot be obtained
454     * @throws UnsupportedTemporalTypeException if the field is not supported
455     */
456    @Override
457    public ValueRange range(TemporalField field) {
458        if (field instanceof ChronoField) {
459            if (field == OFFSET_SECONDS) {
460                return field.range();
461            }
462            return time.range(field);
463        }
464        return field.rangeRefinedBy(this);
465    }
466
467    /**
468     * Gets the value of the specified field from this time as an {@code int}.
469     * <p>
470     * This queries this time for the value of the specified field.
471     * The returned value will always be within the valid range of values for the field.
472     * If it is not possible to return the value, because the field is not supported
473     * or for some other reason, an exception is thrown.
474     * <p>
475     * If the field is a {@link ChronoField} then the query is implemented here.
476     * The {@link #isSupported(TemporalField) supported fields} will return valid
477     * values based on this time, except {@code NANO_OF_DAY} and {@code MICRO_OF_DAY}
478     * which are too large to fit in an {@code int} and throw a {@code DateTimeException}.
479     * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
480     * <p>
481     * If the field is not a {@code ChronoField}, then the result of this method
482     * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
483     * passing {@code this} as the argument. Whether the value can be obtained,
484     * and what the value represents, is determined by the field.
485     *
486     * @param field  the field to get, not null
487     * @return the value for the field
488     * @throws DateTimeException if a value for the field cannot be obtained or
489     *         the value is outside the range of valid values for the field
490     * @throws UnsupportedTemporalTypeException if the field is not supported or
491     *         the range of values exceeds an {@code int}
492     * @throws ArithmeticException if numeric overflow occurs
493     */
494    @Override  // override for Javadoc
495    public int get(TemporalField field) {
496        return Temporal.super.get(field);
497    }
498
499    /**
500     * Gets the value of the specified field from this time as a {@code long}.
501     * <p>
502     * This queries this time for the value of the specified field.
503     * If it is not possible to return the value, because the field is not supported
504     * or for some other reason, an exception is thrown.
505     * <p>
506     * If the field is a {@link ChronoField} then the query is implemented here.
507     * The {@link #isSupported(TemporalField) supported fields} will return valid
508     * values based on this time.
509     * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
510     * <p>
511     * If the field is not a {@code ChronoField}, then the result of this method
512     * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
513     * passing {@code this} as the argument. Whether the value can be obtained,
514     * and what the value represents, is determined by the field.
515     *
516     * @param field  the field to get, not null
517     * @return the value for the field
518     * @throws DateTimeException if a value for the field cannot be obtained
519     * @throws UnsupportedTemporalTypeException if the field is not supported
520     * @throws ArithmeticException if numeric overflow occurs
521     */
522    @Override
523    public long getLong(TemporalField field) {
524        if (field instanceof ChronoField) {
525            if (field == OFFSET_SECONDS) {
526                return offset.getTotalSeconds();
527            }
528            return time.getLong(field);
529        }
530        return field.getFrom(this);
531    }
532
533    //-----------------------------------------------------------------------
534    /**
535     * Gets the zone offset, such as '+01:00'.
536     * <p>
537     * This is the offset of the local time from UTC/Greenwich.
538     *
539     * @return the zone offset, not null
540     */
541    public ZoneOffset getOffset() {
542        return offset;
543    }
544
545    /**
546     * Returns a copy of this {@code OffsetTime} with the specified offset ensuring
547     * that the result has the same local time.
548     * <p>
549     * This method returns an object with the same {@code LocalTime} and the specified {@code ZoneOffset}.
550     * No calculation is needed or performed.
551     * For example, if this time represents {@code 10:30+02:00} and the offset specified is
552     * {@code +03:00}, then this method will return {@code 10:30+03:00}.
553     * <p>
554     * To take into account the difference between the offsets, and adjust the time fields,
555     * use {@link #withOffsetSameInstant}.
556     * <p>
557     * This instance is immutable and unaffected by this method call.
558     *
559     * @param offset  the zone offset to change to, not null
560     * @return an {@code OffsetTime} based on this time with the requested offset, not null
561     */
562    public OffsetTime withOffsetSameLocal(ZoneOffset offset) {
563        return offset != null && offset.equals(this.offset) ? this : new OffsetTime(time, offset);
564    }
565
566    /**
567     * Returns a copy of this {@code OffsetTime} with the specified offset ensuring
568     * that the result is at the same instant on an implied day.
569     * <p>
570     * This method returns an object with the specified {@code ZoneOffset} and a {@code LocalTime}
571     * adjusted by the difference between the two offsets.
572     * This will result in the old and new objects representing the same instant on an implied day.
573     * This is useful for finding the local time in a different offset.
574     * For example, if this time represents {@code 10:30+02:00} and the offset specified is
575     * {@code +03:00}, then this method will return {@code 11:30+03:00}.
576     * <p>
577     * To change the offset without adjusting the local time use {@link #withOffsetSameLocal}.
578     * <p>
579     * This instance is immutable and unaffected by this method call.
580     *
581     * @param offset  the zone offset to change to, not null
582     * @return an {@code OffsetTime} based on this time with the requested offset, not null
583     */
584    public OffsetTime withOffsetSameInstant(ZoneOffset offset) {
585        if (offset.equals(this.offset)) {
586            return this;
587        }
588        int difference = offset.getTotalSeconds() - this.offset.getTotalSeconds();
589        LocalTime adjusted = time.plusSeconds(difference);
590        return new OffsetTime(adjusted, offset);
591    }
592
593    //-----------------------------------------------------------------------
594    /**
595     * Gets the {@code LocalTime} part of this date-time.
596     * <p>
597     * This returns a {@code LocalTime} with the same hour, minute, second and
598     * nanosecond as this date-time.
599     *
600     * @return the time part of this date-time, not null
601     */
602    public LocalTime toLocalTime() {
603        return time;
604    }
605
606    //-----------------------------------------------------------------------
607    /**
608     * Gets the hour-of-day field.
609     *
610     * @return the hour-of-day, from 0 to 23
611     */
612    public int getHour() {
613        return time.getHour();
614    }
615
616    /**
617     * Gets the minute-of-hour field.
618     *
619     * @return the minute-of-hour, from 0 to 59
620     */
621    public int getMinute() {
622        return time.getMinute();
623    }
624
625    /**
626     * Gets the second-of-minute field.
627     *
628     * @return the second-of-minute, from 0 to 59
629     */
630    public int getSecond() {
631        return time.getSecond();
632    }
633
634    /**
635     * Gets the nano-of-second field.
636     *
637     * @return the nano-of-second, from 0 to 999,999,999
638     */
639    public int getNano() {
640        return time.getNano();
641    }
642
643    //-----------------------------------------------------------------------
644    /**
645     * Returns an adjusted copy of this time.
646     * <p>
647     * This returns an {@code OffsetTime}, based on this one, with the time adjusted.
648     * The adjustment takes place using the specified adjuster strategy object.
649     * Read the documentation of the adjuster to understand what adjustment will be made.
650     * <p>
651     * A simple adjuster might simply set the one of the fields, such as the hour field.
652     * A more complex adjuster might set the time to the last hour of the day.
653     * <p>
654     * The classes {@link LocalTime} and {@link ZoneOffset} implement {@code TemporalAdjuster},
655     * thus this method can be used to change the time or offset:
656     * <pre>
657     *  result = offsetTime.with(time);
658     *  result = offsetTime.with(offset);
659     * </pre>
660     * <p>
661     * The result of this method is obtained by invoking the
662     * {@link TemporalAdjuster#adjustInto(Temporal)} method on the
663     * specified adjuster passing {@code this} as the argument.
664     * <p>
665     * This instance is immutable and unaffected by this method call.
666     *
667     * @param adjuster the adjuster to use, not null
668     * @return an {@code OffsetTime} based on {@code this} with the adjustment made, not null
669     * @throws DateTimeException if the adjustment cannot be made
670     * @throws ArithmeticException if numeric overflow occurs
671     */
672    @Override
673    public OffsetTime with(TemporalAdjuster adjuster) {
674        // optimizations
675        if (adjuster instanceof LocalTime) {
676            return with((LocalTime) adjuster, offset);
677        } else if (adjuster instanceof ZoneOffset) {
678            return with(time, (ZoneOffset) adjuster);
679        } else if (adjuster instanceof OffsetTime) {
680            return (OffsetTime) adjuster;
681        }
682        return (OffsetTime) adjuster.adjustInto(this);
683    }
684
685    /**
686     * Returns a copy of this time with the specified field set to a new value.
687     * <p>
688     * This returns an {@code OffsetTime}, based on this one, with the value
689     * for the specified field changed.
690     * This can be used to change any supported field, such as the hour, minute or second.
691     * If it is not possible to set the value, because the field is not supported or for
692     * some other reason, an exception is thrown.
693     * <p>
694     * If the field is a {@link ChronoField} then the adjustment is implemented here.
695     * <p>
696     * The {@code OFFSET_SECONDS} field will return a time with the specified offset.
697     * The local time is unaltered. If the new offset value is outside the valid range
698     * then a {@code DateTimeException} will be thrown.
699     * <p>
700     * The other {@link #isSupported(TemporalField) supported fields} will behave as per
701     * the matching method on {@link LocalTime#with(TemporalField, long)} LocalTime}.
702     * In this case, the offset is not part of the calculation and will be unchanged.
703     * <p>
704     * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
705     * <p>
706     * If the field is not a {@code ChronoField}, then the result of this method
707     * is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
708     * passing {@code this} as the argument. In this case, the field determines
709     * whether and how to adjust the instant.
710     * <p>
711     * This instance is immutable and unaffected by this method call.
712     *
713     * @param field  the field to set in the result, not null
714     * @param newValue  the new value of the field in the result
715     * @return an {@code OffsetTime} based on {@code this} with the specified field set, not null
716     * @throws DateTimeException if the field cannot be set
717     * @throws UnsupportedTemporalTypeException if the field is not supported
718     * @throws ArithmeticException if numeric overflow occurs
719     */
720    @Override
721    public OffsetTime with(TemporalField field, long newValue) {
722        if (field instanceof ChronoField) {
723            if (field == OFFSET_SECONDS) {
724                ChronoField f = (ChronoField) field;
725                return with(time, ZoneOffset.ofTotalSeconds(f.checkValidIntValue(newValue)));
726            }
727            return with(time.with(field, newValue), offset);
728        }
729        return field.adjustInto(this, newValue);
730    }
731
732    //-----------------------------------------------------------------------
733    /**
734     * Returns a copy of this {@code OffsetTime} with the hour-of-day altered.
735     * <p>
736     * The offset does not affect the calculation and will be the same in the result.
737     * <p>
738     * This instance is immutable and unaffected by this method call.
739     *
740     * @param hour  the hour-of-day to set in the result, from 0 to 23
741     * @return an {@code OffsetTime} based on this time with the requested hour, not null
742     * @throws DateTimeException if the hour value is invalid
743     */
744    public OffsetTime withHour(int hour) {
745        return with(time.withHour(hour), offset);
746    }
747
748    /**
749     * Returns a copy of this {@code OffsetTime} with the minute-of-hour altered.
750     * <p>
751     * The offset does not affect the calculation and will be the same in the result.
752     * <p>
753     * This instance is immutable and unaffected by this method call.
754     *
755     * @param minute  the minute-of-hour to set in the result, from 0 to 59
756     * @return an {@code OffsetTime} based on this time with the requested minute, not null
757     * @throws DateTimeException if the minute value is invalid
758     */
759    public OffsetTime withMinute(int minute) {
760        return with(time.withMinute(minute), offset);
761    }
762
763    /**
764     * Returns a copy of this {@code OffsetTime} with the second-of-minute altered.
765     * <p>
766     * The offset does not affect the calculation and will be the same in the result.
767     * <p>
768     * This instance is immutable and unaffected by this method call.
769     *
770     * @param second  the second-of-minute to set in the result, from 0 to 59
771     * @return an {@code OffsetTime} based on this time with the requested second, not null
772     * @throws DateTimeException if the second value is invalid
773     */
774    public OffsetTime withSecond(int second) {
775        return with(time.withSecond(second), offset);
776    }
777
778    /**
779     * Returns a copy of this {@code OffsetTime} with the nano-of-second altered.
780     * <p>
781     * The offset does not affect the calculation and will be the same in the result.
782     * <p>
783     * This instance is immutable and unaffected by this method call.
784     *
785     * @param nanoOfSecond  the nano-of-second to set in the result, from 0 to 999,999,999
786     * @return an {@code OffsetTime} based on this time with the requested nanosecond, not null
787     * @throws DateTimeException if the nanos value is invalid
788     */
789    public OffsetTime withNano(int nanoOfSecond) {
790        return with(time.withNano(nanoOfSecond), offset);
791    }
792
793    //-----------------------------------------------------------------------
794    /**
795     * Returns a copy of this {@code OffsetTime} with the time truncated.
796     * <p>
797     * Truncation returns a copy of the original time with fields
798     * smaller than the specified unit set to zero.
799     * For example, truncating with the {@link ChronoUnit#MINUTES minutes} unit
800     * will set the second-of-minute and nano-of-second field to zero.
801     * <p>
802     * The unit must have a {@linkplain TemporalUnit#getDuration() duration}
803     * that divides into the length of a standard day without remainder.
804     * This includes all supplied time units on {@link ChronoUnit} and
805     * {@link ChronoUnit#DAYS DAYS}. Other units throw an exception.
806     * <p>
807     * The offset does not affect the calculation and will be the same in the result.
808     * <p>
809     * This instance is immutable and unaffected by this method call.
810     *
811     * @param unit  the unit to truncate to, not null
812     * @return an {@code OffsetTime} based on this time with the time truncated, not null
813     * @throws DateTimeException if unable to truncate
814     * @throws UnsupportedTemporalTypeException if the unit is not supported
815     */
816    public OffsetTime truncatedTo(TemporalUnit unit) {
817        return with(time.truncatedTo(unit), offset);
818    }
819
820    //-----------------------------------------------------------------------
821    /**
822     * Returns a copy of this time with the specified amount added.
823     * <p>
824     * This returns an {@code OffsetTime}, based on this one, with the specified amount added.
825     * The amount is typically {@link Duration} but may be any other type implementing
826     * the {@link TemporalAmount} interface.
827     * <p>
828     * The calculation is delegated to the amount object by calling
829     * {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
830     * to implement the addition in any way it wishes, however it typically
831     * calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
832     * of the amount implementation to determine if it can be successfully added.
833     * <p>
834     * This instance is immutable and unaffected by this method call.
835     *
836     * @param amountToAdd  the amount to add, not null
837     * @return an {@code OffsetTime} based on this time with the addition made, not null
838     * @throws DateTimeException if the addition cannot be made
839     * @throws ArithmeticException if numeric overflow occurs
840     */
841    @Override
842    public OffsetTime plus(TemporalAmount amountToAdd) {
843        return (OffsetTime) amountToAdd.addTo(this);
844    }
845
846    /**
847     * Returns a copy of this time with the specified amount added.
848     * <p>
849     * This returns an {@code OffsetTime}, based on this one, with the amount
850     * in terms of the unit added. If it is not possible to add the amount, because the
851     * unit is not supported or for some other reason, an exception is thrown.
852     * <p>
853     * If the field is a {@link ChronoUnit} then the addition is implemented by
854     * {@link LocalTime#plus(long, TemporalUnit)}.
855     * The offset is not part of the calculation and will be unchanged in the result.
856     * <p>
857     * If the field is not a {@code ChronoUnit}, then the result of this method
858     * is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
859     * passing {@code this} as the argument. In this case, the unit determines
860     * whether and how to perform the addition.
861     * <p>
862     * This instance is immutable and unaffected by this method call.
863     *
864     * @param amountToAdd  the amount of the unit to add to the result, may be negative
865     * @param unit  the unit of the amount to add, not null
866     * @return an {@code OffsetTime} based on this time with the specified amount added, not null
867     * @throws DateTimeException if the addition cannot be made
868     * @throws UnsupportedTemporalTypeException if the unit is not supported
869     * @throws ArithmeticException if numeric overflow occurs
870     */
871    @Override
872    public OffsetTime plus(long amountToAdd, TemporalUnit unit) {
873        if (unit instanceof ChronoUnit) {
874            return with(time.plus(amountToAdd, unit), offset);
875        }
876        return unit.addTo(this, amountToAdd);
877    }
878
879    //-----------------------------------------------------------------------
880    /**
881     * Returns a copy of this {@code OffsetTime} with the specified number of hours added.
882     * <p>
883     * This adds the specified number of hours to this time, returning a new time.
884     * The calculation wraps around midnight.
885     * <p>
886     * This instance is immutable and unaffected by this method call.
887     *
888     * @param hours  the hours to add, may be negative
889     * @return an {@code OffsetTime} based on this time with the hours added, not null
890     */
891    public OffsetTime plusHours(long hours) {
892        return with(time.plusHours(hours), offset);
893    }
894
895    /**
896     * Returns a copy of this {@code OffsetTime} with the specified number of minutes added.
897     * <p>
898     * This adds the specified number of minutes to this time, returning a new time.
899     * The calculation wraps around midnight.
900     * <p>
901     * This instance is immutable and unaffected by this method call.
902     *
903     * @param minutes  the minutes to add, may be negative
904     * @return an {@code OffsetTime} based on this time with the minutes added, not null
905     */
906    public OffsetTime plusMinutes(long minutes) {
907        return with(time.plusMinutes(minutes), offset);
908    }
909
910    /**
911     * Returns a copy of this {@code OffsetTime} with the specified number of seconds added.
912     * <p>
913     * This adds the specified number of seconds to this time, returning a new time.
914     * The calculation wraps around midnight.
915     * <p>
916     * This instance is immutable and unaffected by this method call.
917     *
918     * @param seconds  the seconds to add, may be negative
919     * @return an {@code OffsetTime} based on this time with the seconds added, not null
920     */
921    public OffsetTime plusSeconds(long seconds) {
922        return with(time.plusSeconds(seconds), offset);
923    }
924
925    /**
926     * Returns a copy of this {@code OffsetTime} with the specified number of nanoseconds added.
927     * <p>
928     * This adds the specified number of nanoseconds to this time, returning a new time.
929     * The calculation wraps around midnight.
930     * <p>
931     * This instance is immutable and unaffected by this method call.
932     *
933     * @param nanos  the nanos to add, may be negative
934     * @return an {@code OffsetTime} based on this time with the nanoseconds added, not null
935     */
936    public OffsetTime plusNanos(long nanos) {
937        return with(time.plusNanos(nanos), offset);
938    }
939
940    //-----------------------------------------------------------------------
941    /**
942     * Returns a copy of this time with the specified amount subtracted.
943     * <p>
944     * This returns an {@code OffsetTime}, based on this one, with the specified amount subtracted.
945     * The amount is typically {@link Duration} but may be any other type implementing
946     * the {@link TemporalAmount} interface.
947     * <p>
948     * The calculation is delegated to the amount object by calling
949     * {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
950     * to implement the subtraction in any way it wishes, however it typically
951     * calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
952     * of the amount implementation to determine if it can be successfully subtracted.
953     * <p>
954     * This instance is immutable and unaffected by this method call.
955     *
956     * @param amountToSubtract  the amount to subtract, not null
957     * @return an {@code OffsetTime} based on this time with the subtraction made, not null
958     * @throws DateTimeException if the subtraction cannot be made
959     * @throws ArithmeticException if numeric overflow occurs
960     */
961    @Override
962    public OffsetTime minus(TemporalAmount amountToSubtract) {
963        return (OffsetTime) amountToSubtract.subtractFrom(this);
964    }
965
966    /**
967     * Returns a copy of this time with the specified amount subtracted.
968     * <p>
969     * This returns an {@code OffsetTime}, based on this one, with the amount
970     * in terms of the unit subtracted. If it is not possible to subtract the amount,
971     * because the unit is not supported or for some other reason, an exception is thrown.
972     * <p>
973     * This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
974     * See that method for a full description of how addition, and thus subtraction, works.
975     * <p>
976     * This instance is immutable and unaffected by this method call.
977     *
978     * @param amountToSubtract  the amount of the unit to subtract from the result, may be negative
979     * @param unit  the unit of the amount to subtract, not null
980     * @return an {@code OffsetTime} based on this time with the specified amount subtracted, not null
981     * @throws DateTimeException if the subtraction cannot be made
982     * @throws UnsupportedTemporalTypeException if the unit is not supported
983     * @throws ArithmeticException if numeric overflow occurs
984     */
985    @Override
986    public OffsetTime minus(long amountToSubtract, TemporalUnit unit) {
987        return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
988    }
989
990    //-----------------------------------------------------------------------
991    /**
992     * Returns a copy of this {@code OffsetTime} with the specified number of hours subtracted.
993     * <p>
994     * This subtracts the specified number of hours from this time, returning a new time.
995     * The calculation wraps around midnight.
996     * <p>
997     * This instance is immutable and unaffected by this method call.
998     *
999     * @param hours  the hours to subtract, may be negative
1000     * @return an {@code OffsetTime} based on this time with the hours subtracted, not null
1001     */
1002    public OffsetTime minusHours(long hours) {
1003        return with(time.minusHours(hours), offset);
1004    }
1005
1006    /**
1007     * Returns a copy of this {@code OffsetTime} with the specified number of minutes subtracted.
1008     * <p>
1009     * This subtracts the specified number of minutes from this time, returning a new time.
1010     * The calculation wraps around midnight.
1011     * <p>
1012     * This instance is immutable and unaffected by this method call.
1013     *
1014     * @param minutes  the minutes to subtract, may be negative
1015     * @return an {@code OffsetTime} based on this time with the minutes subtracted, not null
1016     */
1017    public OffsetTime minusMinutes(long minutes) {
1018        return with(time.minusMinutes(minutes), offset);
1019    }
1020
1021    /**
1022     * Returns a copy of this {@code OffsetTime} with the specified number of seconds subtracted.
1023     * <p>
1024     * This subtracts the specified number of seconds from this time, returning a new time.
1025     * The calculation wraps around midnight.
1026     * <p>
1027     * This instance is immutable and unaffected by this method call.
1028     *
1029     * @param seconds  the seconds to subtract, may be negative
1030     * @return an {@code OffsetTime} based on this time with the seconds subtracted, not null
1031     */
1032    public OffsetTime minusSeconds(long seconds) {
1033        return with(time.minusSeconds(seconds), offset);
1034    }
1035
1036    /**
1037     * Returns a copy of this {@code OffsetTime} with the specified number of nanoseconds subtracted.
1038     * <p>
1039     * This subtracts the specified number of nanoseconds from this time, returning a new time.
1040     * The calculation wraps around midnight.
1041     * <p>
1042     * This instance is immutable and unaffected by this method call.
1043     *
1044     * @param nanos  the nanos to subtract, may be negative
1045     * @return an {@code OffsetTime} based on this time with the nanoseconds subtracted, not null
1046     */
1047    public OffsetTime minusNanos(long nanos) {
1048        return with(time.minusNanos(nanos), offset);
1049    }
1050
1051    //-----------------------------------------------------------------------
1052    /**
1053     * Queries this time using the specified query.
1054     * <p>
1055     * This queries this time using the specified query strategy object.
1056     * The {@code TemporalQuery} object defines the logic to be used to
1057     * obtain the result. Read the documentation of the query to understand
1058     * what the result of this method will be.
1059     * <p>
1060     * The result of this method is obtained by invoking the
1061     * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
1062     * specified query passing {@code this} as the argument.
1063     *
1064     * @param <R> the type of the result
1065     * @param query  the query to invoke, not null
1066     * @return the query result, null may be returned (defined by the query)
1067     * @throws DateTimeException if unable to query (defined by the query)
1068     * @throws ArithmeticException if numeric overflow occurs (defined by the query)
1069     */
1070    @SuppressWarnings("unchecked")
1071    @Override
1072    public <R> R query(TemporalQuery<R> query) {
1073        if (query == TemporalQueries.offset() || query == TemporalQueries.zone()) {
1074            return (R) offset;
1075        } else if (query == TemporalQueries.zoneId() | query == TemporalQueries.chronology() || query == TemporalQueries.localDate()) {
1076            return null;
1077        } else if (query == TemporalQueries.localTime()) {
1078            return (R) time;
1079        } else if (query == TemporalQueries.precision()) {
1080            return (R) NANOS;
1081        }
1082        // inline TemporalAccessor.super.query(query) as an optimization
1083        // non-JDK classes are not permitted to make this optimization
1084        return query.queryFrom(this);
1085    }
1086
1087    /**
1088     * Adjusts the specified temporal object to have the same offset and time
1089     * as this object.
1090     * <p>
1091     * This returns a temporal object of the same observable type as the input
1092     * with the offset and time changed to be the same as this.
1093     * <p>
1094     * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
1095     * twice, passing {@link ChronoField#NANO_OF_DAY} and
1096     * {@link ChronoField#OFFSET_SECONDS} as the fields.
1097     * <p>
1098     * In most cases, it is clearer to reverse the calling pattern by using
1099     * {@link Temporal#with(TemporalAdjuster)}:
1100     * <pre>
1101     *   // these two lines are equivalent, but the second approach is recommended
1102     *   temporal = thisOffsetTime.adjustInto(temporal);
1103     *   temporal = temporal.with(thisOffsetTime);
1104     * </pre>
1105     * <p>
1106     * This instance is immutable and unaffected by this method call.
1107     *
1108     * @param temporal  the target object to be adjusted, not null
1109     * @return the adjusted object, not null
1110     * @throws DateTimeException if unable to make the adjustment
1111     * @throws ArithmeticException if numeric overflow occurs
1112     */
1113    @Override
1114    public Temporal adjustInto(Temporal temporal) {
1115        return temporal
1116                .with(NANO_OF_DAY, time.toNanoOfDay())
1117                .with(OFFSET_SECONDS, offset.getTotalSeconds());
1118    }
1119
1120    /**
1121     * Calculates the amount of time until another time in terms of the specified unit.
1122     * <p>
1123     * This calculates the amount of time between two {@code OffsetTime}
1124     * objects in terms of a single {@code TemporalUnit}.
1125     * The start and end points are {@code this} and the specified time.
1126     * The result will be negative if the end is before the start.
1127     * For example, the amount in hours between two times can be calculated
1128     * using {@code startTime.until(endTime, HOURS)}.
1129     * <p>
1130     * The {@code Temporal} passed to this method is converted to a
1131     * {@code OffsetTime} using {@link #from(TemporalAccessor)}.
1132     * If the offset differs between the two times, then the specified
1133     * end time is normalized to have the same offset as this time.
1134     * <p>
1135     * The calculation returns a whole number, representing the number of
1136     * complete units between the two times.
1137     * For example, the amount in hours between 11:30Z and 13:29Z will only
1138     * be one hour as it is one minute short of two hours.
1139     * <p>
1140     * There are two equivalent ways of using this method.
1141     * The first is to invoke this method.
1142     * The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
1143     * <pre>
1144     *   // these two lines are equivalent
1145     *   amount = start.until(end, MINUTES);
1146     *   amount = MINUTES.between(start, end);
1147     * </pre>
1148     * The choice should be made based on which makes the code more readable.
1149     * <p>
1150     * The calculation is implemented in this method for {@link ChronoUnit}.
1151     * The units {@code NANOS}, {@code MICROS}, {@code MILLIS}, {@code SECONDS},
1152     * {@code MINUTES}, {@code HOURS} and {@code HALF_DAYS} are supported.
1153     * Other {@code ChronoUnit} values will throw an exception.
1154     * <p>
1155     * If the unit is not a {@code ChronoUnit}, then the result of this method
1156     * is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
1157     * passing {@code this} as the first argument and the converted input temporal
1158     * as the second argument.
1159     * <p>
1160     * This instance is immutable and unaffected by this method call.
1161     *
1162     * @param endExclusive  the end time, exclusive, which is converted to an {@code OffsetTime}, not null
1163     * @param unit  the unit to measure the amount in, not null
1164     * @return the amount of time between this time and the end time
1165     * @throws DateTimeException if the amount cannot be calculated, or the end
1166     *  temporal cannot be converted to an {@code OffsetTime}
1167     * @throws UnsupportedTemporalTypeException if the unit is not supported
1168     * @throws ArithmeticException if numeric overflow occurs
1169     */
1170    @Override
1171    public long until(Temporal endExclusive, TemporalUnit unit) {
1172        OffsetTime end = OffsetTime.from(endExclusive);
1173        if (unit instanceof ChronoUnit) {
1174            long nanosUntil = end.toEpochNano() - toEpochNano();  // no overflow
1175            switch ((ChronoUnit) unit) {
1176                case NANOS: return nanosUntil;
1177                case MICROS: return nanosUntil / 1000;
1178                case MILLIS: return nanosUntil / 1000_000;
1179                case SECONDS: return nanosUntil / NANOS_PER_SECOND;
1180                case MINUTES: return nanosUntil / NANOS_PER_MINUTE;
1181                case HOURS: return nanosUntil / NANOS_PER_HOUR;
1182                case HALF_DAYS: return nanosUntil / (12 * NANOS_PER_HOUR);
1183            }
1184            throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1185        }
1186        return unit.between(this, end);
1187    }
1188
1189    /**
1190     * Formats this time using the specified formatter.
1191     * <p>
1192     * This time will be passed to the formatter to produce a string.
1193     *
1194     * @param formatter  the formatter to use, not null
1195     * @return the formatted time string, not null
1196     * @throws DateTimeException if an error occurs during printing
1197     */
1198    public String format(DateTimeFormatter formatter) {
1199        Objects.requireNonNull(formatter, "formatter");
1200        return formatter.format(this);
1201    }
1202
1203    //-----------------------------------------------------------------------
1204    /**
1205     * Combines this time with a date to create an {@code OffsetDateTime}.
1206     * <p>
1207     * This returns an {@code OffsetDateTime} formed from this time and the specified date.
1208     * All possible combinations of date and time are valid.
1209     *
1210     * @param date  the date to combine with, not null
1211     * @return the offset date-time formed from this time and the specified date, not null
1212     */
1213    public OffsetDateTime atDate(LocalDate date) {
1214        return OffsetDateTime.of(date, time, offset);
1215    }
1216
1217    //-----------------------------------------------------------------------
1218    /**
1219     * Converts this time to epoch nanos based on 1970-01-01Z.
1220     *
1221     * @return the epoch nanos value
1222     */
1223    private long toEpochNano() {
1224        long nod = time.toNanoOfDay();
1225        long offsetNanos = offset.getTotalSeconds() * NANOS_PER_SECOND;
1226        return nod - offsetNanos;
1227    }
1228
1229    //-----------------------------------------------------------------------
1230    /**
1231     * Compares this {@code OffsetTime} to another time.
1232     * <p>
1233     * The comparison is based first on the UTC equivalent instant, then on the local time.
1234     * It is "consistent with equals", as defined by {@link Comparable}.
1235     * <p>
1236     * For example, the following is the comparator order:
1237     * <ol>
1238     * <li>{@code 10:30+01:00}</li>
1239     * <li>{@code 11:00+01:00}</li>
1240     * <li>{@code 12:00+02:00}</li>
1241     * <li>{@code 11:30+01:00}</li>
1242     * <li>{@code 12:00+01:00}</li>
1243     * <li>{@code 12:30+01:00}</li>
1244     * </ol>
1245     * Values #2 and #3 represent the same instant on the time-line.
1246     * When two values represent the same instant, the local time is compared
1247     * to distinguish them. This step is needed to make the ordering
1248     * consistent with {@code equals()}.
1249     * <p>
1250     * To compare the underlying local time of two {@code TemporalAccessor} instances,
1251     * use {@link ChronoField#NANO_OF_DAY} as a comparator.
1252     *
1253     * @param other  the other time to compare to, not null
1254     * @return the comparator value, negative if less, positive if greater
1255     * @throws NullPointerException if {@code other} is null
1256     */
1257    @Override
1258    public int compareTo(OffsetTime other) {
1259        if (offset.equals(other.offset)) {
1260            return time.compareTo(other.time);
1261        }
1262        int compare = Long.compare(toEpochNano(), other.toEpochNano());
1263        if (compare == 0) {
1264            compare = time.compareTo(other.time);
1265        }
1266        return compare;
1267    }
1268
1269    //-----------------------------------------------------------------------
1270    /**
1271     * Checks if the instant of this {@code OffsetTime} is after that of the
1272     * specified time applying both times to a common date.
1273     * <p>
1274     * This method differs from the comparison in {@link #compareTo} in that it
1275     * only compares the instant of the time. This is equivalent to converting both
1276     * times to an instant using the same date and comparing the instants.
1277     *
1278     * @param other  the other time to compare to, not null
1279     * @return true if this is after the instant of the specified time
1280     */
1281    public boolean isAfter(OffsetTime other) {
1282        return toEpochNano() > other.toEpochNano();
1283    }
1284
1285    /**
1286     * Checks if the instant of this {@code OffsetTime} is before that of the
1287     * specified time applying both times to a common date.
1288     * <p>
1289     * This method differs from the comparison in {@link #compareTo} in that it
1290     * only compares the instant of the time. This is equivalent to converting both
1291     * times to an instant using the same date and comparing the instants.
1292     *
1293     * @param other  the other time to compare to, not null
1294     * @return true if this is before the instant of the specified time
1295     */
1296    public boolean isBefore(OffsetTime other) {
1297        return toEpochNano() < other.toEpochNano();
1298    }
1299
1300    /**
1301     * Checks if the instant of this {@code OffsetTime} is equal to that of the
1302     * specified time applying both times to a common date.
1303     * <p>
1304     * This method differs from the comparison in {@link #compareTo} and {@link #equals}
1305     * in that it only compares the instant of the time. This is equivalent to converting both
1306     * times to an instant using the same date and comparing the instants.
1307     *
1308     * @param other  the other time to compare to, not null
1309     * @return true if this is equal to the instant of the specified time
1310     */
1311    public boolean isEqual(OffsetTime other) {
1312        return toEpochNano() == other.toEpochNano();
1313    }
1314
1315    //-----------------------------------------------------------------------
1316    /**
1317     * Checks if this time is equal to another time.
1318     * <p>
1319     * The comparison is based on the local-time and the offset.
1320     * To compare for the same instant on the time-line, use {@link #isEqual(OffsetTime)}.
1321     * <p>
1322     * Only objects of type {@code OffsetTime} are compared, other types return false.
1323     * To compare the underlying local time of two {@code TemporalAccessor} instances,
1324     * use {@link ChronoField#NANO_OF_DAY} as a comparator.
1325     *
1326     * @param obj  the object to check, null returns false
1327     * @return true if this is equal to the other time
1328     */
1329    @Override
1330    public boolean equals(Object obj) {
1331        if (this == obj) {
1332            return true;
1333        }
1334        if (obj instanceof OffsetTime) {
1335            OffsetTime other = (OffsetTime) obj;
1336            return time.equals(other.time) && offset.equals(other.offset);
1337        }
1338        return false;
1339    }
1340
1341    /**
1342     * A hash code for this time.
1343     *
1344     * @return a suitable hash code
1345     */
1346    @Override
1347    public int hashCode() {
1348        return time.hashCode() ^ offset.hashCode();
1349    }
1350
1351    //-----------------------------------------------------------------------
1352    /**
1353     * Outputs this time as a {@code String}, such as {@code 10:15:30+01:00}.
1354     * <p>
1355     * The output will be one of the following ISO-8601 formats:
1356     * <ul>
1357     * <li>{@code HH:mmXXXXX}</li>
1358     * <li>{@code HH:mm:ssXXXXX}</li>
1359     * <li>{@code HH:mm:ss.SSSXXXXX}</li>
1360     * <li>{@code HH:mm:ss.SSSSSSXXXXX}</li>
1361     * <li>{@code HH:mm:ss.SSSSSSSSSXXXXX}</li>
1362     * </ul>
1363     * The format used will be the shortest that outputs the full value of
1364     * the time where the omitted parts are implied to be zero.
1365     *
1366     * @return a string representation of this time, not null
1367     */
1368    @Override
1369    public String toString() {
1370        return time.toString() + offset.toString();
1371    }
1372
1373    //-----------------------------------------------------------------------
1374    /**
1375     * Writes the object using a
1376     * <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
1377     * @serialData
1378     * <pre>
1379     *  out.writeByte(9);  // identifies an OffsetTime
1380     *  // the <a href="../../serialized-form.html#java.time.LocalTime">time</a> excluding the one byte header
1381     *  // the <a href="../../serialized-form.html#java.time.ZoneOffset">offset</a> excluding the one byte header
1382     * </pre>
1383     *
1384     * @return the instance of {@code Ser}, not null
1385     */
1386    private Object writeReplace() {
1387        return new Ser(Ser.OFFSET_TIME_TYPE, this);
1388    }
1389
1390    /**
1391     * Defend against malicious streams.
1392     *
1393     * @param s the stream to read
1394     * @throws InvalidObjectException always
1395     */
1396    private void readObject(ObjectInputStream s) throws InvalidObjectException {
1397        throw new InvalidObjectException("Deserialization via serialization delegate");
1398    }
1399
1400    void writeExternal(ObjectOutput out) throws IOException {
1401        time.writeExternal(out);
1402        offset.writeExternal(out);
1403    }
1404
1405    static OffsetTime readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
1406        LocalTime time = LocalTime.readExternal(in);
1407        ZoneOffset offset = ZoneOffset.readExternal(in);
1408        return OffsetTime.of(time, offset);
1409    }
1410
1411}
1412