1 /*
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   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
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   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
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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  *
  39  *  * Redistributions of source code must retain the above copyright notice,
  40  *    this list of conditions and the following disclaimer.
  41  *
  42  *  * Redistributions in binary form must reproduce the above copyright notice,
  43  *    this list of conditions and the following disclaimer in the documentation
  44  *    and/or other materials provided with the distribution.
  45  *
  46  *  * Neither the name of JSR-310 nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  54  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  55  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  56  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  57  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  58  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  59  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  60  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  */
  62 package java.time;
  63 
  64 import static java.time.LocalTime.NANOS_PER_HOUR;
  65 import static java.time.LocalTime.NANOS_PER_MINUTE;
  66 import static java.time.LocalTime.NANOS_PER_SECOND;
  67 import static java.time.LocalTime.SECONDS_PER_DAY;
  68 import static java.time.temporal.ChronoField.NANO_OF_DAY;
  69 import static java.time.temporal.ChronoField.OFFSET_SECONDS;
  70 import static java.time.temporal.ChronoUnit.NANOS;
  71 
  72 import java.io.IOException;
  73 import java.io.ObjectInput;
  74 import java.io.ObjectOutput;
  75 import java.io.InvalidObjectException;
  76 import java.io.ObjectInputStream;
  77 import java.io.Serializable;
  78 import java.time.format.DateTimeFormatter;
  79 import java.time.format.DateTimeParseException;
  80 import java.time.temporal.ChronoField;
  81 import java.time.temporal.ChronoUnit;
  82 import java.time.temporal.Temporal;
  83 import java.time.temporal.TemporalAccessor;
  84 import java.time.temporal.TemporalAdjuster;
  85 import java.time.temporal.TemporalAmount;
  86 import java.time.temporal.TemporalField;
  87 import java.time.temporal.TemporalQueries;
  88 import java.time.temporal.TemporalQuery;
  89 import java.time.temporal.TemporalUnit;
  90 import java.time.temporal.UnsupportedTemporalTypeException;
  91 import java.time.temporal.ValueRange;
  92 import java.time.zone.ZoneRules;
  93 import java.util.Objects;
  94 
  95 /**
  96  * A time with an offset from UTC/Greenwich in the ISO-8601 calendar system,
  97  * such as {@code 10:15:30+01:00}.
  98  * <p>
  99  * {@code OffsetTime} is an immutable date-time object that represents a time, often
 100  * viewed as hour-minute-second-offset.
 101  * This class stores all time fields, to a precision of nanoseconds,
 102  * as well as a zone offset.
 103  * For example, the value "13:45:30.123456789+02:00" can be stored
 104  * in an {@code OffsetTime}.
 105  * <p>
 106  * This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
 107  * class; programmers should treat instances that are
 108  * {@linkplain #equals(Object) equal} as interchangeable and should not
 109  * use instances for synchronization, or unpredictable behavior may
 110  * occur. For example, in a future release, synchronization may fail.
 111  * The {@code equals} method should be used for comparisons.
 112  *
 113  * @implSpec
 114  * This class is immutable and thread-safe.
 115  *
 116  * @since 1.8
 117  */
 118 @jdk.internal.ValueBased
 119 @jdk.internal.MigratedValueClass
 120 public final class OffsetTime
 121         implements Temporal, TemporalAdjuster, Comparable<OffsetTime>, Serializable {
 122 
 123     /**
 124      * The minimum supported {@code OffsetTime}, '00:00:00+18:00'.
 125      * This is the time of midnight at the start of the day in the maximum offset
 126      * (larger offsets are earlier on the time-line).
 127      * This combines {@link LocalTime#MIN} and {@link ZoneOffset#MAX}.
 128      * This could be used by an application as a "far past" date.
 129      */
 130     public static final OffsetTime MIN = LocalTime.MIN.atOffset(ZoneOffset.MAX);
 131     /**
 132      * The maximum supported {@code OffsetTime}, '23:59:59.999999999-18:00'.
 133      * This is the time just before midnight at the end of the day in the minimum offset
 134      * (larger negative offsets are later on the time-line).
 135      * This combines {@link LocalTime#MAX} and {@link ZoneOffset#MIN}.
 136      * This could be used by an application as a "far future" date.
 137      */
 138     public static final OffsetTime MAX = LocalTime.MAX.atOffset(ZoneOffset.MIN);
 139 
 140     /**
 141      * Serialization version.
 142      */
 143     @java.io.Serial
 144     private static final long serialVersionUID = 7264499704384272492L;
 145 
 146     /**
 147      * The local date-time.
 148      */
 149     private final LocalTime time;
 150     /**
 151      * The offset from UTC/Greenwich.
 152      */
 153     private final ZoneOffset offset;
 154 
 155     //-----------------------------------------------------------------------
 156     /**
 157      * Obtains the current time from the system clock in the default time-zone.
 158      * <p>
 159      * This will query the {@link Clock#systemDefaultZone() system clock} in the default
 160      * time-zone to obtain the current time.
 161      * The offset will be calculated from the time-zone in the clock.
 162      * <p>
 163      * Using this method will prevent the ability to use an alternate clock for testing
 164      * because the clock is hard-coded.
 165      *
 166      * @return the current time using the system clock and default time-zone, not null
 167      */
 168     public static OffsetTime now() {
 169         return now(Clock.systemDefaultZone());
 170     }
 171 
 172     /**
 173      * Obtains the current time from the system clock in the specified time-zone.
 174      * <p>
 175      * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current time.
 176      * Specifying the time-zone avoids dependence on the default time-zone.
 177      * The offset will be calculated from the specified time-zone.
 178      * <p>
 179      * Using this method will prevent the ability to use an alternate clock for testing
 180      * because the clock is hard-coded.
 181      *
 182      * @param zone  the zone ID to use, not null
 183      * @return the current time using the system clock, not null
 184      */
 185     public static OffsetTime now(ZoneId zone) {
 186         return now(Clock.system(zone));
 187     }
 188 
 189     /**
 190      * Obtains the current time from the specified clock.
 191      * <p>
 192      * This will query the specified clock to obtain the current time.
 193      * The offset will be calculated from the time-zone in the clock.
 194      * <p>
 195      * Using this method allows the use of an alternate clock for testing.
 196      * The alternate clock may be introduced using {@link Clock dependency injection}.
 197      *
 198      * @param clock  the clock to use, not null
 199      * @return the current time, not null
 200      */
 201     public static OffsetTime now(Clock clock) {
 202         Objects.requireNonNull(clock, "clock");
 203         final Instant now = clock.instant();  // called once
 204         return ofInstant(now, clock.getZone().getRules().getOffset(now));
 205     }
 206 
 207     //-----------------------------------------------------------------------
 208     /**
 209      * Obtains an instance of {@code OffsetTime} from a local time and an offset.
 210      *
 211      * @param time  the local time, not null
 212      * @param offset  the zone offset, not null
 213      * @return the offset time, not null
 214      */
 215     public static OffsetTime of(LocalTime time, ZoneOffset offset) {
 216         return new OffsetTime(time, offset);
 217     }
 218 
 219     /**
 220      * Obtains an instance of {@code OffsetTime} from an hour, minute, second and nanosecond.
 221      * <p>
 222      * This creates an offset time with the four specified fields.
 223      * <p>
 224      * This method exists primarily for writing test cases.
 225      * Non test-code will typically use other methods to create an offset time.
 226      * {@code LocalTime} has two additional convenience variants of the
 227      * equivalent factory method taking fewer arguments.
 228      * They are not provided here to reduce the footprint of the API.
 229      *
 230      * @param hour  the hour-of-day to represent, from 0 to 23
 231      * @param minute  the minute-of-hour to represent, from 0 to 59
 232      * @param second  the second-of-minute to represent, from 0 to 59
 233      * @param nanoOfSecond  the nano-of-second to represent, from 0 to 999,999,999
 234      * @param offset  the zone offset, not null
 235      * @return the offset time, not null
 236      * @throws DateTimeException if the value of any field is out of range
 237      */
 238     public static OffsetTime of(int hour, int minute, int second, int nanoOfSecond, ZoneOffset offset) {
 239         return new OffsetTime(LocalTime.of(hour, minute, second, nanoOfSecond), offset);
 240     }
 241 
 242     //-----------------------------------------------------------------------
 243     /**
 244      * Obtains an instance of {@code OffsetTime} from an {@code Instant} and zone ID.
 245      * <p>
 246      * This creates an offset time with the same instant as that specified.
 247      * Finding the offset from UTC/Greenwich is simple as there is only one valid
 248      * offset for each instant.
 249      * <p>
 250      * The date component of the instant is dropped during the conversion.
 251      * This means that the conversion can never fail due to the instant being
 252      * out of the valid range of dates.
 253      *
 254      * @param instant  the instant to create the time from, not null
 255      * @param zone  the time-zone, which may be an offset, not null
 256      * @return the offset time, not null
 257      */
 258     public static OffsetTime ofInstant(Instant instant, ZoneId zone) {
 259         Objects.requireNonNull(instant, "instant");
 260         Objects.requireNonNull(zone, "zone");
 261         ZoneRules rules = zone.getRules();
 262         ZoneOffset offset = rules.getOffset(instant);
 263         long localSecond = instant.getEpochSecond() + offset.getTotalSeconds();  // overflow caught later
 264         int secsOfDay = Math.floorMod(localSecond, SECONDS_PER_DAY);
 265         LocalTime time = LocalTime.ofNanoOfDay(secsOfDay * NANOS_PER_SECOND + instant.getNano());
 266         return new OffsetTime(time, offset);
 267     }
 268 
 269     //-----------------------------------------------------------------------
 270     /**
 271      * Obtains an instance of {@code OffsetTime} from a temporal object.
 272      * <p>
 273      * This obtains an offset time based on the specified temporal.
 274      * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
 275      * which this factory converts to an instance of {@code OffsetTime}.
 276      * <p>
 277      * The conversion extracts and combines the {@code ZoneOffset} and the
 278      * {@code LocalTime} from the temporal object.
 279      * Implementations are permitted to perform optimizations such as accessing
 280      * those fields that are equivalent to the relevant objects.
 281      * <p>
 282      * This method matches the signature of the functional interface {@link TemporalQuery}
 283      * allowing it to be used as a query via method reference, {@code OffsetTime::from}.
 284      *
 285      * @param temporal  the temporal object to convert, not null
 286      * @return the offset time, not null
 287      * @throws DateTimeException if unable to convert to an {@code OffsetTime}
 288      */
 289     public static OffsetTime from(TemporalAccessor temporal) {
 290         if (temporal instanceof OffsetTime) {
 291             return (OffsetTime) temporal;
 292         }
 293         try {
 294             LocalTime time = LocalTime.from(temporal);
 295             ZoneOffset offset = ZoneOffset.from(temporal);
 296             return new OffsetTime(time, offset);
 297         } catch (DateTimeException ex) {
 298             throw new DateTimeException("Unable to obtain OffsetTime from TemporalAccessor: " +
 299                     temporal + " of type " + temporal.getClass().getName(), ex);
 300         }
 301     }
 302 
 303     //-----------------------------------------------------------------------
 304     /**
 305      * Obtains an instance of {@code OffsetTime} from a text string such as {@code 10:15:30+01:00}.
 306      * <p>
 307      * The string must represent a valid time and is parsed using
 308      * {@link java.time.format.DateTimeFormatter#ISO_OFFSET_TIME}.
 309      *
 310      * @param text  the text to parse such as "10:15:30+01:00", not null
 311      * @return the parsed local time, not null
 312      * @throws DateTimeParseException if the text cannot be parsed
 313      */
 314     public static OffsetTime parse(CharSequence text) {
 315         return parse(text, DateTimeFormatter.ISO_OFFSET_TIME);
 316     }
 317 
 318     /**
 319      * Obtains an instance of {@code OffsetTime} from a text string using a specific formatter.
 320      * <p>
 321      * The text is parsed using the formatter, returning a time.
 322      *
 323      * @param text  the text to parse, not null
 324      * @param formatter  the formatter to use, not null
 325      * @return the parsed offset time, not null
 326      * @throws DateTimeParseException if the text cannot be parsed
 327      */
 328     public static OffsetTime parse(CharSequence text, DateTimeFormatter formatter) {
 329         Objects.requireNonNull(formatter, "formatter");
 330         return formatter.parse(text, OffsetTime::from);
 331     }
 332 
 333     //-----------------------------------------------------------------------
 334     /**
 335      * Constructor.
 336      *
 337      * @param time  the local time, not null
 338      * @param offset  the zone offset, not null
 339      */
 340     private OffsetTime(LocalTime time, ZoneOffset offset) {
 341         this.time = Objects.requireNonNull(time, "time");
 342         this.offset = Objects.requireNonNull(offset, "offset");
 343     }
 344 
 345     /**
 346      * Returns a new time based on this one, returning {@code this} where possible.
 347      *
 348      * @param time  the time to create with, not null
 349      * @param offset  the zone offset to create with, not null
 350      */
 351     private OffsetTime with(LocalTime time, ZoneOffset offset) {
 352         if (this.time == time && this.offset.equals(offset)) {
 353             return this;
 354         }
 355         return new OffsetTime(time, offset);
 356     }
 357 
 358     //-----------------------------------------------------------------------
 359     /**
 360      * Checks if the specified field is supported.
 361      * <p>
 362      * This checks if this time can be queried for the specified field.
 363      * If false, then calling the {@link #range(TemporalField) range},
 364      * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
 365      * methods will throw an exception.
 366      * <p>
 367      * If the field is a {@link ChronoField} then the query is implemented here.
 368      * The supported fields are:
 369      * <ul>
 370      * <li>{@code NANO_OF_SECOND}
 371      * <li>{@code NANO_OF_DAY}
 372      * <li>{@code MICRO_OF_SECOND}
 373      * <li>{@code MICRO_OF_DAY}
 374      * <li>{@code MILLI_OF_SECOND}
 375      * <li>{@code MILLI_OF_DAY}
 376      * <li>{@code SECOND_OF_MINUTE}
 377      * <li>{@code SECOND_OF_DAY}
 378      * <li>{@code MINUTE_OF_HOUR}
 379      * <li>{@code MINUTE_OF_DAY}
 380      * <li>{@code HOUR_OF_AMPM}
 381      * <li>{@code CLOCK_HOUR_OF_AMPM}
 382      * <li>{@code HOUR_OF_DAY}
 383      * <li>{@code CLOCK_HOUR_OF_DAY}
 384      * <li>{@code AMPM_OF_DAY}
 385      * <li>{@code OFFSET_SECONDS}
 386      * </ul>
 387      * All other {@code ChronoField} instances will return false.
 388      * <p>
 389      * If the field is not a {@code ChronoField}, then the result of this method
 390      * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
 391      * passing {@code this} as the argument.
 392      * Whether the field is supported is determined by the field.
 393      *
 394      * @param field  the field to check, null returns false
 395      * @return true if the field is supported on this time, false if not
 396      */
 397     @Override
 398     public boolean isSupported(TemporalField field) {
 399         if (field instanceof ChronoField) {
 400             return field.isTimeBased() || field == OFFSET_SECONDS;
 401         }
 402         return field != null && field.isSupportedBy(this);
 403     }
 404 
 405     /**
 406      * Checks if the specified unit is supported.
 407      * <p>
 408      * This checks if the specified unit can be added to, or subtracted from, this offset-time.
 409      * If false, then calling the {@link #plus(long, TemporalUnit)} and
 410      * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
 411      * <p>
 412      * If the unit is a {@link ChronoUnit} then the query is implemented here.
 413      * The supported units are:
 414      * <ul>
 415      * <li>{@code NANOS}
 416      * <li>{@code MICROS}
 417      * <li>{@code MILLIS}
 418      * <li>{@code SECONDS}
 419      * <li>{@code MINUTES}
 420      * <li>{@code HOURS}
 421      * <li>{@code HALF_DAYS}
 422      * </ul>
 423      * All other {@code ChronoUnit} instances will return false.
 424      * <p>
 425      * If the unit is not a {@code ChronoUnit}, then the result of this method
 426      * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
 427      * passing {@code this} as the argument.
 428      * Whether the unit is supported is determined by the unit.
 429      *
 430      * @param unit  the unit to check, null returns false
 431      * @return true if the unit can be added/subtracted, false if not
 432      */
 433     @Override  // override for Javadoc
 434     public boolean isSupported(TemporalUnit unit) {
 435         if (unit instanceof ChronoUnit) {
 436             return unit.isTimeBased();
 437         }
 438         return unit != null && unit.isSupportedBy(this);
 439     }
 440 
 441     //-----------------------------------------------------------------------
 442     /**
 443      * Gets the range of valid values for the specified field.
 444      * <p>
 445      * The range object expresses the minimum and maximum valid values for a field.
 446      * This time is used to enhance the accuracy of the returned range.
 447      * If it is not possible to return the range, because the field is not supported
 448      * or for some other reason, an exception is thrown.
 449      * <p>
 450      * If the field is a {@link ChronoField} then the query is implemented here.
 451      * The {@link #isSupported(TemporalField) supported fields} will return
 452      * appropriate range instances.
 453      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 454      * <p>
 455      * If the field is not a {@code ChronoField}, then the result of this method
 456      * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
 457      * passing {@code this} as the argument.
 458      * Whether the range can be obtained is determined by the field.
 459      *
 460      * @param field  the field to query the range for, not null
 461      * @return the range of valid values for the field, not null
 462      * @throws DateTimeException if the range for the field cannot be obtained
 463      * @throws UnsupportedTemporalTypeException if the field is not supported
 464      */
 465     @Override
 466     public ValueRange range(TemporalField field) {
 467         if (field instanceof ChronoField) {
 468             if (field == OFFSET_SECONDS) {
 469                 return field.range();
 470             }
 471             return time.range(field);
 472         }
 473         return field.rangeRefinedBy(this);
 474     }
 475 
 476     /**
 477      * Gets the value of the specified field from this time as an {@code int}.
 478      * <p>
 479      * This queries this time for the value of the specified field.
 480      * The returned value will always be within the valid range of values for the field.
 481      * If it is not possible to return the value, because the field is not supported
 482      * or for some other reason, an exception is thrown.
 483      * <p>
 484      * If the field is a {@link ChronoField} then the query is implemented here.
 485      * The {@link #isSupported(TemporalField) supported fields} will return valid
 486      * values based on this time, except {@code NANO_OF_DAY} and {@code MICRO_OF_DAY}
 487      * which are too large to fit in an {@code int} and throw an {@code UnsupportedTemporalTypeException}.
 488      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 489      * <p>
 490      * If the field is not a {@code ChronoField}, then the result of this method
 491      * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
 492      * passing {@code this} as the argument. Whether the value can be obtained,
 493      * and what the value represents, is determined by the field.
 494      *
 495      * @param field  the field to get, not null
 496      * @return the value for the field
 497      * @throws DateTimeException if a value for the field cannot be obtained or
 498      *         the value is outside the range of valid values for the field
 499      * @throws UnsupportedTemporalTypeException if the field is not supported or
 500      *         the range of values exceeds an {@code int}
 501      * @throws ArithmeticException if numeric overflow occurs
 502      */
 503     @Override  // override for Javadoc
 504     public int get(TemporalField field) {
 505         return Temporal.super.get(field);
 506     }
 507 
 508     /**
 509      * Gets the value of the specified field from this time as a {@code long}.
 510      * <p>
 511      * This queries this time for the value of the specified field.
 512      * If it is not possible to return the value, because the field is not supported
 513      * or for some other reason, an exception is thrown.
 514      * <p>
 515      * If the field is a {@link ChronoField} then the query is implemented here.
 516      * The {@link #isSupported(TemporalField) supported fields} will return valid
 517      * values based on this time.
 518      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 519      * <p>
 520      * If the field is not a {@code ChronoField}, then the result of this method
 521      * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
 522      * passing {@code this} as the argument. Whether the value can be obtained,
 523      * and what the value represents, is determined by the field.
 524      *
 525      * @param field  the field to get, not null
 526      * @return the value for the field
 527      * @throws DateTimeException if a value for the field cannot be obtained
 528      * @throws UnsupportedTemporalTypeException if the field is not supported
 529      * @throws ArithmeticException if numeric overflow occurs
 530      */
 531     @Override
 532     public long getLong(TemporalField field) {
 533         if (field instanceof ChronoField) {
 534             if (field == OFFSET_SECONDS) {
 535                 return offset.getTotalSeconds();
 536             }
 537             return time.getLong(field);
 538         }
 539         return field.getFrom(this);
 540     }
 541 
 542     //-----------------------------------------------------------------------
 543     /**
 544      * Gets the zone offset, such as '+01:00'.
 545      * <p>
 546      * This is the offset of the local time from UTC/Greenwich.
 547      *
 548      * @return the zone offset, not null
 549      */
 550     public ZoneOffset getOffset() {
 551         return offset;
 552     }
 553 
 554     /**
 555      * Returns a copy of this {@code OffsetTime} with the specified offset ensuring
 556      * that the result has the same local time.
 557      * <p>
 558      * This method returns an object with the same {@code LocalTime} and the specified {@code ZoneOffset}.
 559      * No calculation is needed or performed.
 560      * For example, if this time represents {@code 10:30+02:00} and the offset specified is
 561      * {@code +03:00}, then this method will return {@code 10:30+03:00}.
 562      * <p>
 563      * To take into account the difference between the offsets, and adjust the time fields,
 564      * use {@link #withOffsetSameInstant}.
 565      * <p>
 566      * This instance is immutable and unaffected by this method call.
 567      *
 568      * @param offset  the zone offset to change to, not null
 569      * @return an {@code OffsetTime} based on this time with the requested offset, not null
 570      */
 571     public OffsetTime withOffsetSameLocal(ZoneOffset offset) {
 572         return offset != null && offset.equals(this.offset) ? this : new OffsetTime(time, offset);
 573     }
 574 
 575     /**
 576      * Returns a copy of this {@code OffsetTime} with the specified offset ensuring
 577      * that the result is at the same instant on an implied day.
 578      * <p>
 579      * This method returns an object with the specified {@code ZoneOffset} and a {@code LocalTime}
 580      * adjusted by the difference between the two offsets.
 581      * This will result in the old and new objects representing the same instant on an implied day.
 582      * This is useful for finding the local time in a different offset.
 583      * For example, if this time represents {@code 10:30+02:00} and the offset specified is
 584      * {@code +03:00}, then this method will return {@code 11:30+03:00}.
 585      * <p>
 586      * To change the offset without adjusting the local time use {@link #withOffsetSameLocal}.
 587      * <p>
 588      * This instance is immutable and unaffected by this method call.
 589      *
 590      * @param offset  the zone offset to change to, not null
 591      * @return an {@code OffsetTime} based on this time with the requested offset, not null
 592      */
 593     public OffsetTime withOffsetSameInstant(ZoneOffset offset) {
 594         if (offset.equals(this.offset)) {
 595             return this;
 596         }
 597         int difference = offset.getTotalSeconds() - this.offset.getTotalSeconds();
 598         LocalTime adjusted = time.plusSeconds(difference);
 599         return new OffsetTime(adjusted, offset);
 600     }
 601 
 602     //-----------------------------------------------------------------------
 603     /**
 604      * Gets the {@code LocalTime} part of this date-time.
 605      * <p>
 606      * This returns a {@code LocalTime} with the same hour, minute, second and
 607      * nanosecond as this date-time.
 608      *
 609      * @return the time part of this date-time, not null
 610      */
 611     public LocalTime toLocalTime() {
 612         return time;
 613     }
 614 
 615     //-----------------------------------------------------------------------
 616     /**
 617      * Gets the hour-of-day field.
 618      *
 619      * @return the hour-of-day, from 0 to 23
 620      */
 621     public int getHour() {
 622         return time.getHour();
 623     }
 624 
 625     /**
 626      * Gets the minute-of-hour field.
 627      *
 628      * @return the minute-of-hour, from 0 to 59
 629      */
 630     public int getMinute() {
 631         return time.getMinute();
 632     }
 633 
 634     /**
 635      * Gets the second-of-minute field.
 636      *
 637      * @return the second-of-minute, from 0 to 59
 638      */
 639     public int getSecond() {
 640         return time.getSecond();
 641     }
 642 
 643     /**
 644      * Gets the nano-of-second field.
 645      *
 646      * @return the nano-of-second, from 0 to 999,999,999
 647      */
 648     public int getNano() {
 649         return time.getNano();
 650     }
 651 
 652     //-----------------------------------------------------------------------
 653     /**
 654      * Returns an adjusted copy of this time.
 655      * <p>
 656      * This returns an {@code OffsetTime}, based on this one, with the time adjusted.
 657      * The adjustment takes place using the specified adjuster strategy object.
 658      * Read the documentation of the adjuster to understand what adjustment will be made.
 659      * <p>
 660      * A simple adjuster might simply set the one of the fields, such as the hour field.
 661      * A more complex adjuster might set the time to the last hour of the day.
 662      * <p>
 663      * The classes {@link LocalTime} and {@link ZoneOffset} implement {@code TemporalAdjuster},
 664      * thus this method can be used to change the time or offset:
 665      * <pre>
 666      *  result = offsetTime.with(time);
 667      *  result = offsetTime.with(offset);
 668      * </pre>
 669      * <p>
 670      * The result of this method is obtained by invoking the
 671      * {@link TemporalAdjuster#adjustInto(Temporal)} method on the
 672      * specified adjuster passing {@code this} as the argument.
 673      * <p>
 674      * This instance is immutable and unaffected by this method call.
 675      *
 676      * @param adjuster the adjuster to use, not null
 677      * @return an {@code OffsetTime} based on {@code this} with the adjustment made, not null
 678      * @throws DateTimeException if the adjustment cannot be made
 679      * @throws ArithmeticException if numeric overflow occurs
 680      */
 681     @Override
 682     public OffsetTime with(TemporalAdjuster adjuster) {
 683         // optimizations
 684         if (adjuster instanceof LocalTime) {
 685             return with((LocalTime) adjuster, offset);
 686         } else if (adjuster instanceof ZoneOffset) {
 687             return with(time, (ZoneOffset) adjuster);
 688         } else if (adjuster instanceof OffsetTime) {
 689             return (OffsetTime) adjuster;
 690         }
 691         return (OffsetTime) adjuster.adjustInto(this);
 692     }
 693 
 694     /**
 695      * Returns a copy of this time with the specified field set to a new value.
 696      * <p>
 697      * This returns an {@code OffsetTime}, based on this one, with the value
 698      * for the specified field changed.
 699      * This can be used to change any supported field, such as the hour, minute or second.
 700      * If it is not possible to set the value, because the field is not supported or for
 701      * some other reason, an exception is thrown.
 702      * <p>
 703      * If the field is a {@link ChronoField} then the adjustment is implemented here.
 704      * <p>
 705      * The {@code OFFSET_SECONDS} field will return a time with the specified offset.
 706      * The local time is unaltered. If the new offset value is outside the valid range
 707      * then a {@code DateTimeException} will be thrown.
 708      * <p>
 709      * The other {@link #isSupported(TemporalField) supported fields} will behave as per
 710      * the matching method on {@link LocalTime#with(TemporalField, long)} LocalTime}.
 711      * In this case, the offset is not part of the calculation and will be unchanged.
 712      * <p>
 713      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 714      * <p>
 715      * If the field is not a {@code ChronoField}, then the result of this method
 716      * is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
 717      * passing {@code this} as the argument. In this case, the field determines
 718      * whether and how to adjust the instant.
 719      * <p>
 720      * This instance is immutable and unaffected by this method call.
 721      *
 722      * @param field  the field to set in the result, not null
 723      * @param newValue  the new value of the field in the result
 724      * @return an {@code OffsetTime} based on {@code this} with the specified field set, not null
 725      * @throws DateTimeException if the field cannot be set
 726      * @throws UnsupportedTemporalTypeException if the field is not supported
 727      * @throws ArithmeticException if numeric overflow occurs
 728      */
 729     @Override
 730     public OffsetTime with(TemporalField field, long newValue) {
 731         if (field instanceof ChronoField) {
 732             if (field == OFFSET_SECONDS) {
 733                 ChronoField f = (ChronoField) field;
 734                 return with(time, ZoneOffset.ofTotalSeconds(f.checkValidIntValue(newValue)));
 735             }
 736             return with(time.with(field, newValue), offset);
 737         }
 738         return field.adjustInto(this, newValue);
 739     }
 740 
 741     //-----------------------------------------------------------------------
 742     /**
 743      * Returns a copy of this {@code OffsetTime} with the hour-of-day altered.
 744      * <p>
 745      * The offset does not affect the calculation and will be the same in the result.
 746      * <p>
 747      * This instance is immutable and unaffected by this method call.
 748      *
 749      * @param hour  the hour-of-day to set in the result, from 0 to 23
 750      * @return an {@code OffsetTime} based on this time with the requested hour, not null
 751      * @throws DateTimeException if the hour value is invalid
 752      */
 753     public OffsetTime withHour(int hour) {
 754         return with(time.withHour(hour), offset);
 755     }
 756 
 757     /**
 758      * Returns a copy of this {@code OffsetTime} with the minute-of-hour altered.
 759      * <p>
 760      * The offset does not affect the calculation and will be the same in the result.
 761      * <p>
 762      * This instance is immutable and unaffected by this method call.
 763      *
 764      * @param minute  the minute-of-hour to set in the result, from 0 to 59
 765      * @return an {@code OffsetTime} based on this time with the requested minute, not null
 766      * @throws DateTimeException if the minute value is invalid
 767      */
 768     public OffsetTime withMinute(int minute) {
 769         return with(time.withMinute(minute), offset);
 770     }
 771 
 772     /**
 773      * Returns a copy of this {@code OffsetTime} with the second-of-minute altered.
 774      * <p>
 775      * The offset does not affect the calculation and will be the same in the result.
 776      * <p>
 777      * This instance is immutable and unaffected by this method call.
 778      *
 779      * @param second  the second-of-minute to set in the result, from 0 to 59
 780      * @return an {@code OffsetTime} based on this time with the requested second, not null
 781      * @throws DateTimeException if the second value is invalid
 782      */
 783     public OffsetTime withSecond(int second) {
 784         return with(time.withSecond(second), offset);
 785     }
 786 
 787     /**
 788      * Returns a copy of this {@code OffsetTime} with the nano-of-second altered.
 789      * <p>
 790      * The offset does not affect the calculation and will be the same in the result.
 791      * <p>
 792      * This instance is immutable and unaffected by this method call.
 793      *
 794      * @param nanoOfSecond  the nano-of-second to set in the result, from 0 to 999,999,999
 795      * @return an {@code OffsetTime} based on this time with the requested nanosecond, not null
 796      * @throws DateTimeException if the nanos value is invalid
 797      */
 798     public OffsetTime withNano(int nanoOfSecond) {
 799         return with(time.withNano(nanoOfSecond), offset);
 800     }
 801 
 802     //-----------------------------------------------------------------------
 803     /**
 804      * Returns a copy of this {@code OffsetTime} with the time truncated.
 805      * <p>
 806      * Truncation returns a copy of the original time with fields
 807      * smaller than the specified unit set to zero.
 808      * For example, truncating with the {@link ChronoUnit#MINUTES minutes} unit
 809      * will set the second-of-minute and nano-of-second field to zero.
 810      * <p>
 811      * The unit must have a {@linkplain TemporalUnit#getDuration() duration}
 812      * that divides into the length of a standard day without remainder.
 813      * This includes all supplied time units on {@link ChronoUnit} and
 814      * {@link ChronoUnit#DAYS DAYS}. Other units throw an exception.
 815      * <p>
 816      * The offset does not affect the calculation and will be the same in the result.
 817      * <p>
 818      * This instance is immutable and unaffected by this method call.
 819      *
 820      * @param unit  the unit to truncate to, not null
 821      * @return an {@code OffsetTime} based on this time with the time truncated, not null
 822      * @throws DateTimeException if unable to truncate
 823      * @throws UnsupportedTemporalTypeException if the unit is not supported
 824      */
 825     public OffsetTime truncatedTo(TemporalUnit unit) {
 826         return with(time.truncatedTo(unit), offset);
 827     }
 828 
 829     //-----------------------------------------------------------------------
 830     /**
 831      * Returns a copy of this time with the specified amount added.
 832      * <p>
 833      * This returns an {@code OffsetTime}, based on this one, with the specified amount added.
 834      * The amount is typically {@link Duration} but may be any other type implementing
 835      * the {@link TemporalAmount} interface.
 836      * <p>
 837      * The calculation is delegated to the amount object by calling
 838      * {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
 839      * to implement the addition in any way it wishes, however it typically
 840      * calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
 841      * of the amount implementation to determine if it can be successfully added.
 842      * <p>
 843      * This instance is immutable and unaffected by this method call.
 844      *
 845      * @param amountToAdd  the amount to add, not null
 846      * @return an {@code OffsetTime} based on this time with the addition made, not null
 847      * @throws DateTimeException if the addition cannot be made
 848      * @throws ArithmeticException if numeric overflow occurs
 849      */
 850     @Override
 851     public OffsetTime plus(TemporalAmount amountToAdd) {
 852         return (OffsetTime) amountToAdd.addTo(this);
 853     }
 854 
 855     /**
 856      * Returns a copy of this time with the specified amount added.
 857      * <p>
 858      * This returns an {@code OffsetTime}, based on this one, with the amount
 859      * in terms of the unit added. If it is not possible to add the amount, because the
 860      * unit is not supported or for some other reason, an exception is thrown.
 861      * <p>
 862      * If the field is a {@link ChronoUnit} then the addition is implemented by
 863      * {@link LocalTime#plus(long, TemporalUnit)}.
 864      * The offset is not part of the calculation and will be unchanged in the result.
 865      * <p>
 866      * If the field is not a {@code ChronoUnit}, then the result of this method
 867      * is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
 868      * passing {@code this} as the argument. In this case, the unit determines
 869      * whether and how to perform the addition.
 870      * <p>
 871      * This instance is immutable and unaffected by this method call.
 872      *
 873      * @param amountToAdd  the amount of the unit to add to the result, may be negative
 874      * @param unit  the unit of the amount to add, not null
 875      * @return an {@code OffsetTime} based on this time with the specified amount added, not null
 876      * @throws DateTimeException if the addition cannot be made
 877      * @throws UnsupportedTemporalTypeException if the unit is not supported
 878      * @throws ArithmeticException if numeric overflow occurs
 879      */
 880     @Override
 881     public OffsetTime plus(long amountToAdd, TemporalUnit unit) {
 882         if (unit instanceof ChronoUnit) {
 883             return with(time.plus(amountToAdd, unit), offset);
 884         }
 885         return unit.addTo(this, amountToAdd);
 886     }
 887 
 888     //-----------------------------------------------------------------------
 889     /**
 890      * Returns a copy of this {@code OffsetTime} with the specified number of hours added.
 891      * <p>
 892      * This adds the specified number of hours to this time, returning a new time.
 893      * The calculation wraps around midnight.
 894      * <p>
 895      * This instance is immutable and unaffected by this method call.
 896      *
 897      * @param hours  the hours to add, may be negative
 898      * @return an {@code OffsetTime} based on this time with the hours added, not null
 899      */
 900     public OffsetTime plusHours(long hours) {
 901         return with(time.plusHours(hours), offset);
 902     }
 903 
 904     /**
 905      * Returns a copy of this {@code OffsetTime} with the specified number of minutes added.
 906      * <p>
 907      * This adds the specified number of minutes to this time, returning a new time.
 908      * The calculation wraps around midnight.
 909      * <p>
 910      * This instance is immutable and unaffected by this method call.
 911      *
 912      * @param minutes  the minutes to add, may be negative
 913      * @return an {@code OffsetTime} based on this time with the minutes added, not null
 914      */
 915     public OffsetTime plusMinutes(long minutes) {
 916         return with(time.plusMinutes(minutes), offset);
 917     }
 918 
 919     /**
 920      * Returns a copy of this {@code OffsetTime} with the specified number of seconds added.
 921      * <p>
 922      * This adds the specified number of seconds to this time, returning a new time.
 923      * The calculation wraps around midnight.
 924      * <p>
 925      * This instance is immutable and unaffected by this method call.
 926      *
 927      * @param seconds  the seconds to add, may be negative
 928      * @return an {@code OffsetTime} based on this time with the seconds added, not null
 929      */
 930     public OffsetTime plusSeconds(long seconds) {
 931         return with(time.plusSeconds(seconds), offset);
 932     }
 933 
 934     /**
 935      * Returns a copy of this {@code OffsetTime} with the specified number of nanoseconds added.
 936      * <p>
 937      * This adds the specified number of nanoseconds to this time, returning a new time.
 938      * The calculation wraps around midnight.
 939      * <p>
 940      * This instance is immutable and unaffected by this method call.
 941      *
 942      * @param nanos  the nanos to add, may be negative
 943      * @return an {@code OffsetTime} based on this time with the nanoseconds added, not null
 944      */
 945     public OffsetTime plusNanos(long nanos) {
 946         return with(time.plusNanos(nanos), offset);
 947     }
 948 
 949     //-----------------------------------------------------------------------
 950     /**
 951      * Returns a copy of this time with the specified amount subtracted.
 952      * <p>
 953      * This returns an {@code OffsetTime}, based on this one, with the specified amount subtracted.
 954      * The amount is typically {@link Duration} but may be any other type implementing
 955      * the {@link TemporalAmount} interface.
 956      * <p>
 957      * The calculation is delegated to the amount object by calling
 958      * {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
 959      * to implement the subtraction in any way it wishes, however it typically
 960      * calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
 961      * of the amount implementation to determine if it can be successfully subtracted.
 962      * <p>
 963      * This instance is immutable and unaffected by this method call.
 964      *
 965      * @param amountToSubtract  the amount to subtract, not null
 966      * @return an {@code OffsetTime} based on this time with the subtraction made, not null
 967      * @throws DateTimeException if the subtraction cannot be made
 968      * @throws ArithmeticException if numeric overflow occurs
 969      */
 970     @Override
 971     public OffsetTime minus(TemporalAmount amountToSubtract) {
 972         return (OffsetTime) amountToSubtract.subtractFrom(this);
 973     }
 974 
 975     /**
 976      * Returns a copy of this time with the specified amount subtracted.
 977      * <p>
 978      * This returns an {@code OffsetTime}, based on this one, with the amount
 979      * in terms of the unit subtracted. If it is not possible to subtract the amount,
 980      * because the unit is not supported or for some other reason, an exception is thrown.
 981      * <p>
 982      * This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
 983      * See that method for a full description of how addition, and thus subtraction, works.
 984      * <p>
 985      * This instance is immutable and unaffected by this method call.
 986      *
 987      * @param amountToSubtract  the amount of the unit to subtract from the result, may be negative
 988      * @param unit  the unit of the amount to subtract, not null
 989      * @return an {@code OffsetTime} based on this time with the specified amount subtracted, not null
 990      * @throws DateTimeException if the subtraction cannot be made
 991      * @throws UnsupportedTemporalTypeException if the unit is not supported
 992      * @throws ArithmeticException if numeric overflow occurs
 993      */
 994     @Override
 995     public OffsetTime minus(long amountToSubtract, TemporalUnit unit) {
 996         return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
 997     }
 998 
 999     //-----------------------------------------------------------------------
1000     /**
1001      * Returns a copy of this {@code OffsetTime} with the specified number of hours subtracted.
1002      * <p>
1003      * This subtracts the specified number of hours from this time, returning a new time.
1004      * The calculation wraps around midnight.
1005      * <p>
1006      * This instance is immutable and unaffected by this method call.
1007      *
1008      * @param hours  the hours to subtract, may be negative
1009      * @return an {@code OffsetTime} based on this time with the hours subtracted, not null
1010      */
1011     public OffsetTime minusHours(long hours) {
1012         return with(time.minusHours(hours), offset);
1013     }
1014 
1015     /**
1016      * Returns a copy of this {@code OffsetTime} with the specified number of minutes subtracted.
1017      * <p>
1018      * This subtracts the specified number of minutes from this time, returning a new time.
1019      * The calculation wraps around midnight.
1020      * <p>
1021      * This instance is immutable and unaffected by this method call.
1022      *
1023      * @param minutes  the minutes to subtract, may be negative
1024      * @return an {@code OffsetTime} based on this time with the minutes subtracted, not null
1025      */
1026     public OffsetTime minusMinutes(long minutes) {
1027         return with(time.minusMinutes(minutes), offset);
1028     }
1029 
1030     /**
1031      * Returns a copy of this {@code OffsetTime} with the specified number of seconds subtracted.
1032      * <p>
1033      * This subtracts the specified number of seconds from this time, returning a new time.
1034      * The calculation wraps around midnight.
1035      * <p>
1036      * This instance is immutable and unaffected by this method call.
1037      *
1038      * @param seconds  the seconds to subtract, may be negative
1039      * @return an {@code OffsetTime} based on this time with the seconds subtracted, not null
1040      */
1041     public OffsetTime minusSeconds(long seconds) {
1042         return with(time.minusSeconds(seconds), offset);
1043     }
1044 
1045     /**
1046      * Returns a copy of this {@code OffsetTime} with the specified number of nanoseconds subtracted.
1047      * <p>
1048      * This subtracts the specified number of nanoseconds from this time, returning a new time.
1049      * The calculation wraps around midnight.
1050      * <p>
1051      * This instance is immutable and unaffected by this method call.
1052      *
1053      * @param nanos  the nanos to subtract, may be negative
1054      * @return an {@code OffsetTime} based on this time with the nanoseconds subtracted, not null
1055      */
1056     public OffsetTime minusNanos(long nanos) {
1057         return with(time.minusNanos(nanos), offset);
1058     }
1059 
1060     //-----------------------------------------------------------------------
1061     /**
1062      * Queries this time using the specified query.
1063      * <p>
1064      * This queries this time using the specified query strategy object.
1065      * The {@code TemporalQuery} object defines the logic to be used to
1066      * obtain the result. Read the documentation of the query to understand
1067      * what the result of this method will be.
1068      * <p>
1069      * The result of this method is obtained by invoking the
1070      * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
1071      * specified query passing {@code this} as the argument.
1072      *
1073      * @param <R> the type of the result
1074      * @param query  the query to invoke, not null
1075      * @return the query result, null may be returned (defined by the query)
1076      * @throws DateTimeException if unable to query (defined by the query)
1077      * @throws ArithmeticException if numeric overflow occurs (defined by the query)
1078      */
1079     @SuppressWarnings("unchecked")
1080     @Override
1081     public <R> R query(TemporalQuery<R> query) {
1082         if (query == TemporalQueries.offset() || query == TemporalQueries.zone()) {
1083             return (R) offset;
1084         } else if (query == TemporalQueries.zoneId() | query == TemporalQueries.chronology() || query == TemporalQueries.localDate()) {
1085             return null;
1086         } else if (query == TemporalQueries.localTime()) {
1087             return (R) time;
1088         } else if (query == TemporalQueries.precision()) {
1089             return (R) NANOS;
1090         }
1091         // inline TemporalAccessor.super.query(query) as an optimization
1092         // non-JDK classes are not permitted to make this optimization
1093         return query.queryFrom(this);
1094     }
1095 
1096     /**
1097      * Adjusts the specified temporal object to have the same offset and time
1098      * as this object.
1099      * <p>
1100      * This returns a temporal object of the same observable type as the input
1101      * with the offset and time changed to be the same as this.
1102      * <p>
1103      * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
1104      * twice, passing {@link ChronoField#NANO_OF_DAY} and
1105      * {@link ChronoField#OFFSET_SECONDS} as the fields.
1106      * <p>
1107      * In most cases, it is clearer to reverse the calling pattern by using
1108      * {@link Temporal#with(TemporalAdjuster)}:
1109      * <pre>
1110      *   // these two lines are equivalent, but the second approach is recommended
1111      *   temporal = thisOffsetTime.adjustInto(temporal);
1112      *   temporal = temporal.with(thisOffsetTime);
1113      * </pre>
1114      * <p>
1115      * This instance is immutable and unaffected by this method call.
1116      *
1117      * @param temporal  the target object to be adjusted, not null
1118      * @return the adjusted object, not null
1119      * @throws DateTimeException if unable to make the adjustment
1120      * @throws ArithmeticException if numeric overflow occurs
1121      */
1122     @Override
1123     public Temporal adjustInto(Temporal temporal) {
1124         return temporal
1125                 .with(NANO_OF_DAY, time.toNanoOfDay())
1126                 .with(OFFSET_SECONDS, offset.getTotalSeconds());
1127     }
1128 
1129     /**
1130      * Calculates the amount of time until another time in terms of the specified unit.
1131      * <p>
1132      * This calculates the amount of time between two {@code OffsetTime}
1133      * objects in terms of a single {@code TemporalUnit}.
1134      * The start and end points are {@code this} and the specified time.
1135      * The result will be negative if the end is before the start.
1136      * For example, the amount in hours between two times can be calculated
1137      * using {@code startTime.until(endTime, HOURS)}.
1138      * <p>
1139      * The {@code Temporal} passed to this method is converted to a
1140      * {@code OffsetTime} using {@link #from(TemporalAccessor)}.
1141      * If the offset differs between the two times, then the specified
1142      * end time is normalized to have the same offset as this time.
1143      * <p>
1144      * The calculation returns a whole number, representing the number of
1145      * complete units between the two times.
1146      * For example, the amount in hours between 11:30Z and 13:29Z will only
1147      * be one hour as it is one minute short of two hours.
1148      * <p>
1149      * There are two equivalent ways of using this method.
1150      * The first is to invoke this method.
1151      * The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
1152      * <pre>
1153      *   // these two lines are equivalent
1154      *   amount = start.until(end, MINUTES);
1155      *   amount = MINUTES.between(start, end);
1156      * </pre>
1157      * The choice should be made based on which makes the code more readable.
1158      * <p>
1159      * The calculation is implemented in this method for {@link ChronoUnit}.
1160      * The units {@code NANOS}, {@code MICROS}, {@code MILLIS}, {@code SECONDS},
1161      * {@code MINUTES}, {@code HOURS} and {@code HALF_DAYS} are supported.
1162      * Other {@code ChronoUnit} values will throw an exception.
1163      * <p>
1164      * If the unit is not a {@code ChronoUnit}, then the result of this method
1165      * is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
1166      * passing {@code this} as the first argument and the converted input temporal
1167      * as the second argument.
1168      * <p>
1169      * This instance is immutable and unaffected by this method call.
1170      *
1171      * @param endExclusive  the end time, exclusive, which is converted to an {@code OffsetTime}, not null
1172      * @param unit  the unit to measure the amount in, not null
1173      * @return the amount of time between this time and the end time
1174      * @throws DateTimeException if the amount cannot be calculated, or the end
1175      *  temporal cannot be converted to an {@code OffsetTime}
1176      * @throws UnsupportedTemporalTypeException if the unit is not supported
1177      * @throws ArithmeticException if numeric overflow occurs
1178      */
1179     @Override
1180     public long until(Temporal endExclusive, TemporalUnit unit) {
1181         OffsetTime end = OffsetTime.from(endExclusive);
1182         if (unit instanceof ChronoUnit chronoUnit) {
1183             long nanosUntil = end.toEpochNano() - toEpochNano();  // no overflow
1184             return switch (chronoUnit) {
1185                 case NANOS     -> nanosUntil;
1186                 case MICROS    -> nanosUntil / 1000;
1187                 case MILLIS    -> nanosUntil / 1000_000;
1188                 case SECONDS   -> nanosUntil / NANOS_PER_SECOND;
1189                 case MINUTES   -> nanosUntil / NANOS_PER_MINUTE;
1190                 case HOURS     -> nanosUntil / NANOS_PER_HOUR;
1191                 case HALF_DAYS -> nanosUntil / (12 * NANOS_PER_HOUR);
1192                 default -> throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
1193             };
1194         }
1195         return unit.between(this, end);
1196     }
1197 
1198     /**
1199      * Formats this time using the specified formatter.
1200      * <p>
1201      * This time will be passed to the formatter to produce a string.
1202      *
1203      * @param formatter  the formatter to use, not null
1204      * @return the formatted time string, not null
1205      * @throws DateTimeException if an error occurs during printing
1206      */
1207     public String format(DateTimeFormatter formatter) {
1208         Objects.requireNonNull(formatter, "formatter");
1209         return formatter.format(this);
1210     }
1211 
1212     //-----------------------------------------------------------------------
1213     /**
1214      * Combines this time with a date to create an {@code OffsetDateTime}.
1215      * <p>
1216      * This returns an {@code OffsetDateTime} formed from this time and the specified date.
1217      * All possible combinations of date and time are valid.
1218      *
1219      * @param date  the date to combine with, not null
1220      * @return the offset date-time formed from this time and the specified date, not null
1221      */
1222     public OffsetDateTime atDate(LocalDate date) {
1223         return OffsetDateTime.of(date, time, offset);
1224     }
1225 
1226     //-----------------------------------------------------------------------
1227     /**
1228      * Converts this time to epoch nanos based on 1970-01-01Z.
1229      *
1230      * @return the epoch nanos value
1231      */
1232     private long toEpochNano() {
1233         long nod = time.toNanoOfDay();
1234         long offsetNanos = offset.getTotalSeconds() * NANOS_PER_SECOND;
1235         return nod - offsetNanos;
1236     }
1237 
1238     /**
1239      * Converts this {@code OffsetTime} to the number of seconds since the epoch
1240      * of 1970-01-01T00:00:00Z.
1241      * <p>
1242      * This combines this offset time with the specified date to calculate the
1243      * epoch-second value, which is the number of elapsed seconds from
1244      * 1970-01-01T00:00:00Z.
1245      * Instants on the time-line after the epoch are positive, earlier
1246      * are negative.
1247      *
1248      * @param date the localdate, not null
1249      * @return the number of seconds since the epoch of 1970-01-01T00:00:00Z, may be negative
1250      * @since 9
1251      */
1252     public long toEpochSecond(LocalDate date) {
1253         Objects.requireNonNull(date, "date");
1254         long epochDay = date.toEpochDay();
1255         long secs = epochDay * 86400 + time.toSecondOfDay();
1256         secs -= offset.getTotalSeconds();
1257         return secs;
1258     }
1259 
1260     //-----------------------------------------------------------------------
1261     /**
1262      * Compares this {@code OffsetTime} to another time.
1263      * <p>
1264      * The comparison is based first on the UTC equivalent instant, then on the local time.
1265      * It is "consistent with equals", as defined by {@link Comparable}.
1266      * <p>
1267      * For example, the following is the comparator order:
1268      * <ol>
1269      * <li>{@code 10:30+01:00}</li>
1270      * <li>{@code 11:00+01:00}</li>
1271      * <li>{@code 12:00+02:00}</li>
1272      * <li>{@code 11:30+01:00}</li>
1273      * <li>{@code 12:00+01:00}</li>
1274      * <li>{@code 12:30+01:00}</li>
1275      * </ol>
1276      * Values #2 and #3 represent the same instant on the time-line.
1277      * When two values represent the same instant, the local time is compared
1278      * to distinguish them. This step is needed to make the ordering
1279      * consistent with {@code equals()}.
1280      * <p>
1281      * To compare the underlying local time of two {@code TemporalAccessor} instances,
1282      * use {@link ChronoField#NANO_OF_DAY} as a comparator.
1283      *
1284      * @param other  the other time to compare to, not null
1285      * @return the comparator value, that is the comparison of the UTC equivalent {@code other} instant,
1286      *          if they are not equal, and if the UTC equivalent {@code other} instant is equal,
1287      *          the comparison of this local time with {@code other} local time
1288      * @see #isBefore
1289      * @see #isAfter
1290      */
1291     @Override
1292     public int compareTo(OffsetTime other) {
1293         if (offset.equals(other.offset)) {
1294             return time.compareTo(other.time);
1295         }
1296         int compare = Long.compare(toEpochNano(), other.toEpochNano());
1297         if (compare == 0) {
1298             compare = time.compareTo(other.time);
1299         }
1300         return compare;
1301     }
1302 
1303     //-----------------------------------------------------------------------
1304     /**
1305      * Checks if the instant of this {@code OffsetTime} is after that of the
1306      * specified time applying both times to a common date.
1307      * <p>
1308      * This method differs from the comparison in {@link #compareTo} in that it
1309      * only compares the instant of the time. This is equivalent to converting both
1310      * times to an instant using the same date and comparing the instants.
1311      *
1312      * @param other  the other time to compare to, not null
1313      * @return true if this is after the instant of the specified time
1314      */
1315     public boolean isAfter(OffsetTime other) {
1316         return toEpochNano() > other.toEpochNano();
1317     }
1318 
1319     /**
1320      * Checks if the instant of this {@code OffsetTime} is before that of the
1321      * specified time applying both times to a common date.
1322      * <p>
1323      * This method differs from the comparison in {@link #compareTo} in that it
1324      * only compares the instant of the time. This is equivalent to converting both
1325      * times to an instant using the same date and comparing the instants.
1326      *
1327      * @param other  the other time to compare to, not null
1328      * @return true if this is before the instant of the specified time
1329      */
1330     public boolean isBefore(OffsetTime other) {
1331         return toEpochNano() < other.toEpochNano();
1332     }
1333 
1334     /**
1335      * Checks if the instant of this {@code OffsetTime} is equal to that of the
1336      * specified time applying both times to a common date.
1337      * <p>
1338      * This method differs from the comparison in {@link #compareTo} and {@link #equals}
1339      * in that it only compares the instant of the time. This is equivalent to converting both
1340      * times to an instant using the same date and comparing the instants.
1341      *
1342      * @param other  the other time to compare to, not null
1343      * @return true if this is equal to the instant of the specified time
1344      */
1345     public boolean isEqual(OffsetTime other) {
1346         return toEpochNano() == other.toEpochNano();
1347     }
1348 
1349     //-----------------------------------------------------------------------
1350     /**
1351      * Checks if this time is equal to another time.
1352      * <p>
1353      * The comparison is based on the local-time and the offset.
1354      * To compare for the same instant on the time-line, use {@link #isEqual(OffsetTime)}.
1355      * <p>
1356      * Only objects of type {@code OffsetTime} are compared, other types return false.
1357      * To compare the underlying local time of two {@code TemporalAccessor} instances,
1358      * use {@link ChronoField#NANO_OF_DAY} as a comparator.
1359      *
1360      * @param obj  the object to check, null returns false
1361      * @return true if this is equal to the other time
1362      */
1363     @Override
1364     public boolean equals(Object obj) {
1365         if (this == obj) {
1366             return true;
1367         }
1368         return (obj instanceof OffsetTime other)
1369                 && time.equals(other.time)
1370                 && offset.equals(other.offset);
1371     }
1372 
1373     /**
1374      * A hash code for this time.
1375      *
1376      * @return a suitable hash code
1377      */
1378     @Override
1379     public int hashCode() {
1380         return time.hashCode() ^ offset.hashCode();
1381     }
1382 
1383     //-----------------------------------------------------------------------
1384     /**
1385      * Outputs this time as a {@code String}, such as {@code 10:15:30+01:00}.
1386      * <p>
1387      * The output will be one of the following ISO-8601 formats:
1388      * <ul>
1389      * <li>{@code HH:mmXXXXX}</li>
1390      * <li>{@code HH:mm:ssXXXXX}</li>
1391      * <li>{@code HH:mm:ss.SSSXXXXX}</li>
1392      * <li>{@code HH:mm:ss.SSSSSSXXXXX}</li>
1393      * <li>{@code HH:mm:ss.SSSSSSSSSXXXXX}</li>
1394      * </ul>
1395      * The format used will be the shortest that outputs the full value of
1396      * the time where the omitted parts are implied to be zero.
1397      *
1398      * @return a string representation of this time, not null
1399      */
1400     @Override
1401     public String toString() {
1402         return time.toString() + offset.toString();
1403     }
1404 
1405     //-----------------------------------------------------------------------
1406     /**
1407      * Writes the object using a
1408      * <a href="{@docRoot}/serialized-form.html#java.time.Ser">dedicated serialized form</a>.
1409      * @serialData
1410      * <pre>
1411      *  out.writeByte(9);  // identifies an OffsetTime
1412      *  // the <a href="{@docRoot}/serialized-form.html#java.time.LocalTime">time</a> excluding the one byte header
1413      *  // the <a href="{@docRoot}/serialized-form.html#java.time.ZoneOffset">offset</a> excluding the one byte header
1414      * </pre>
1415      *
1416      * @return the instance of {@code Ser}, not null
1417      */
1418     @java.io.Serial
1419     private Object writeReplace() {
1420         return new Ser(Ser.OFFSET_TIME_TYPE, this);
1421     }
1422 
1423     /**
1424      * Defend against malicious streams.
1425      *
1426      * @param s the stream to read
1427      * @throws InvalidObjectException always
1428      */
1429     @java.io.Serial
1430     private void readObject(ObjectInputStream s) throws InvalidObjectException {
1431         throw new InvalidObjectException("Deserialization via serialization delegate");
1432     }
1433 
1434     void writeExternal(ObjectOutput out) throws IOException {
1435         time.writeExternal(out);
1436         offset.writeExternal(out);
1437     }
1438 
1439     static OffsetTime readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
1440         LocalTime time = LocalTime.readExternal(in);
1441         ZoneOffset offset = ZoneOffset.readExternal(in);
1442         return OffsetTime.of(time, offset);
1443     }
1444 
1445 }