1 /*
   2  * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 /*
  27  * This file is available under and governed by the GNU General Public
  28  * License version 2 only, as published by the Free Software Foundation.
  29  * However, the following notice accompanied the original version of this
  30  * file:
  31  *
  32  * Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
  33  *
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions are met:
  38  *
  39  *  * Redistributions of source code must retain the above copyright notice,
  40  *    this list of conditions and the following disclaimer.
  41  *
  42  *  * Redistributions in binary form must reproduce the above copyright notice,
  43  *    this list of conditions and the following disclaimer in the documentation
  44  *    and/or other materials provided with the distribution.
  45  *
  46  *  * Neither the name of JSR-310 nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  54  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  55  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  56  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  57  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  58  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  59  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  60  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  */
  62 package java.time;
  63 
  64 import static java.time.LocalTime.HOURS_PER_DAY;
  65 import static java.time.LocalTime.MICROS_PER_DAY;
  66 import static java.time.LocalTime.MILLIS_PER_DAY;
  67 import static java.time.LocalTime.MINUTES_PER_DAY;
  68 import static java.time.LocalTime.NANOS_PER_DAY;
  69 import static java.time.LocalTime.NANOS_PER_HOUR;
  70 import static java.time.LocalTime.NANOS_PER_MINUTE;
  71 import static java.time.LocalTime.NANOS_PER_SECOND;
  72 import static java.time.LocalTime.SECONDS_PER_DAY;
  73 import static java.time.temporal.ChronoField.NANO_OF_SECOND;
  74 
  75 import java.io.DataInput;
  76 import java.io.DataOutput;
  77 import java.io.IOException;
  78 import java.io.InvalidObjectException;
  79 import java.io.ObjectInputStream;
  80 import java.io.Serializable;
  81 import java.time.chrono.ChronoLocalDateTime;
  82 import java.time.format.DateTimeFormatter;
  83 import java.time.format.DateTimeParseException;
  84 import java.time.temporal.ChronoField;
  85 import java.time.temporal.ChronoUnit;
  86 import java.time.temporal.Temporal;
  87 import java.time.temporal.TemporalAccessor;
  88 import java.time.temporal.TemporalAdjuster;
  89 import java.time.temporal.TemporalAmount;
  90 import java.time.temporal.TemporalField;
  91 import java.time.temporal.TemporalQueries;
  92 import java.time.temporal.TemporalQuery;
  93 import java.time.temporal.TemporalUnit;
  94 import java.time.temporal.UnsupportedTemporalTypeException;
  95 import java.time.temporal.ValueRange;
  96 import java.time.zone.ZoneRules;
  97 import java.util.Objects;
  98 
  99 /**
 100  * A date-time without a time-zone in the ISO-8601 calendar system,
 101  * such as {@code 2007-12-03T10:15:30}.
 102  * <p>
 103  * {@code LocalDateTime} is an immutable date-time object that represents a date-time,
 104  * often viewed as year-month-day-hour-minute-second. Other date and time fields,
 105  * such as day-of-year, day-of-week and week-of-year, can also be accessed.
 106  * Time is represented to nanosecond precision.
 107  * For example, the value "2nd October 2007 at 13:45.30.123456789" can be
 108  * stored in a {@code LocalDateTime}.
 109  * <p>
 110  * This class does not store or represent a time-zone.
 111  * Instead, it is a description of the date, as used for birthdays, combined with
 112  * the local time as seen on a wall clock.
 113  * It cannot represent an instant on the time-line without additional information
 114  * such as an offset or time-zone.
 115  * <p>
 116  * The ISO-8601 calendar system is the modern civil calendar system used today
 117  * in most of the world. It is equivalent to the proleptic Gregorian calendar
 118  * system, in which today's rules for leap years are applied for all time.
 119  * For most applications written today, the ISO-8601 rules are entirely suitable.
 120  * However, any application that makes use of historical dates, and requires them
 121  * to be accurate will find the ISO-8601 approach unsuitable.
 122  *
 123  * <p>
 124  * This is a <a href="{@docRoot}/java/lang/doc-files/ValueBased.html">value-based</a>
 125  * class; use of identity-sensitive operations (including reference equality
 126  * ({@code ==}), identity hash code, or synchronization) on instances of
 127  * {@code LocalDateTime} may have unpredictable results and should be avoided.
 128  * The {@code equals} method should be used for comparisons.
 129  *
 130  * @implSpec
 131  * This class is immutable and thread-safe.
 132  *
 133  * @since 1.8
 134  */
 135 public final class LocalDateTime
 136         implements Temporal, TemporalAdjuster, ChronoLocalDateTime<LocalDate>, Serializable {
 137 
 138     /**
 139      * The minimum supported {@code LocalDateTime}, '-999999999-01-01T00:00:00'.
 140      * This is the local date-time of midnight at the start of the minimum date.
 141      * This combines {@link LocalDate#MIN} and {@link LocalTime#MIN}.
 142      * This could be used by an application as a "far past" date-time.
 143      */
 144     public static final LocalDateTime MIN = LocalDateTime.of(LocalDate.MIN, LocalTime.MIN);
 145     /**
 146      * The maximum supported {@code LocalDateTime}, '+999999999-12-31T23:59:59.999999999'.
 147      * This is the local date-time just before midnight at the end of the maximum date.
 148      * This combines {@link LocalDate#MAX} and {@link LocalTime#MAX}.
 149      * This could be used by an application as a "far future" date-time.
 150      */
 151     public static final LocalDateTime MAX = LocalDateTime.of(LocalDate.MAX, LocalTime.MAX);
 152 
 153     /**
 154      * Serialization version.
 155      */
 156     private static final long serialVersionUID = 6207766400415563566L;
 157 
 158     /**
 159      * The date part.
 160      */
 161     private final LocalDate date;
 162     /**
 163      * The time part.
 164      */
 165     private final LocalTime time;
 166 
 167     //-----------------------------------------------------------------------
 168     /**
 169      * Obtains the current date-time from the system clock in the default time-zone.
 170      * <p>
 171      * This will query the {@link Clock#systemDefaultZone() system clock} in the default
 172      * time-zone to obtain the current date-time.
 173      * <p>
 174      * Using this method will prevent the ability to use an alternate clock for testing
 175      * because the clock is hard-coded.
 176      *
 177      * @return the current date-time using the system clock and default time-zone, not null
 178      */
 179     public static LocalDateTime now() {
 180         return now(Clock.systemDefaultZone());
 181     }
 182 
 183     /**
 184      * Obtains the current date-time from the system clock in the specified time-zone.
 185      * <p>
 186      * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date-time.
 187      * Specifying the time-zone avoids dependence on the default time-zone.
 188      * <p>
 189      * Using this method will prevent the ability to use an alternate clock for testing
 190      * because the clock is hard-coded.
 191      *
 192      * @param zone  the zone ID to use, not null
 193      * @return the current date-time using the system clock, not null
 194      */
 195     public static LocalDateTime now(ZoneId zone) {
 196         return now(Clock.system(zone));
 197     }
 198 
 199     /**
 200      * Obtains the current date-time from the specified clock.
 201      * <p>
 202      * This will query the specified clock to obtain the current date-time.
 203      * Using this method allows the use of an alternate clock for testing.
 204      * The alternate clock may be introduced using {@link Clock dependency injection}.
 205      *
 206      * @param clock  the clock to use, not null
 207      * @return the current date-time, not null
 208      */
 209     public static LocalDateTime now(Clock clock) {
 210         Objects.requireNonNull(clock, "clock");
 211         final Instant now = clock.instant();  // called once
 212         ZoneOffset offset = clock.getZone().getRules().getOffset(now);
 213         return ofEpochSecond(now.getEpochSecond(), now.getNano(), offset);
 214     }
 215 
 216     //-----------------------------------------------------------------------
 217     /**
 218      * Obtains an instance of {@code LocalDateTime} from year, month,
 219      * day, hour and minute, setting the second and nanosecond to zero.
 220      * <p>
 221      * This returns a {@code LocalDateTime} with the specified year, month,
 222      * day-of-month, hour and minute.
 223      * The day must be valid for the year and month, otherwise an exception will be thrown.
 224      * The second and nanosecond fields will be set to zero.
 225      *
 226      * @param year  the year to represent, from MIN_YEAR to MAX_YEAR
 227      * @param month  the month-of-year to represent, not null
 228      * @param dayOfMonth  the day-of-month to represent, from 1 to 31
 229      * @param hour  the hour-of-day to represent, from 0 to 23
 230      * @param minute  the minute-of-hour to represent, from 0 to 59
 231      * @return the local date-time, not null
 232      * @throws DateTimeException if the value of any field is out of range,
 233      *  or if the day-of-month is invalid for the month-year
 234      */
 235     public static LocalDateTime of(int year, Month month, int dayOfMonth, int hour, int minute) {
 236         LocalDate date = LocalDate.of(year, month, dayOfMonth);
 237         LocalTime time = LocalTime.of(hour, minute);
 238         return new LocalDateTime(date, time);
 239     }
 240 
 241     /**
 242      * Obtains an instance of {@code LocalDateTime} from year, month,
 243      * day, hour, minute and second, setting the nanosecond to zero.
 244      * <p>
 245      * This returns a {@code LocalDateTime} with the specified year, month,
 246      * day-of-month, hour, minute and second.
 247      * The day must be valid for the year and month, otherwise an exception will be thrown.
 248      * The nanosecond field will be set to zero.
 249      *
 250      * @param year  the year to represent, from MIN_YEAR to MAX_YEAR
 251      * @param month  the month-of-year to represent, not null
 252      * @param dayOfMonth  the day-of-month to represent, from 1 to 31
 253      * @param hour  the hour-of-day to represent, from 0 to 23
 254      * @param minute  the minute-of-hour to represent, from 0 to 59
 255      * @param second  the second-of-minute to represent, from 0 to 59
 256      * @return the local date-time, not null
 257      * @throws DateTimeException if the value of any field is out of range,
 258      *  or if the day-of-month is invalid for the month-year
 259      */
 260     public static LocalDateTime of(int year, Month month, int dayOfMonth, int hour, int minute, int second) {
 261         LocalDate date = LocalDate.of(year, month, dayOfMonth);
 262         LocalTime time = LocalTime.of(hour, minute, second);
 263         return new LocalDateTime(date, time);
 264     }
 265 
 266     /**
 267      * Obtains an instance of {@code LocalDateTime} from year, month,
 268      * day, hour, minute, second and nanosecond.
 269      * <p>
 270      * This returns a {@code LocalDateTime} with the specified year, month,
 271      * day-of-month, hour, minute, second and nanosecond.
 272      * The day must be valid for the year and month, otherwise an exception will be thrown.
 273      *
 274      * @param year  the year to represent, from MIN_YEAR to MAX_YEAR
 275      * @param month  the month-of-year to represent, not null
 276      * @param dayOfMonth  the day-of-month to represent, from 1 to 31
 277      * @param hour  the hour-of-day to represent, from 0 to 23
 278      * @param minute  the minute-of-hour to represent, from 0 to 59
 279      * @param second  the second-of-minute to represent, from 0 to 59
 280      * @param nanoOfSecond  the nano-of-second to represent, from 0 to 999,999,999
 281      * @return the local date-time, not null
 282      * @throws DateTimeException if the value of any field is out of range,
 283      *  or if the day-of-month is invalid for the month-year
 284      */
 285     public static LocalDateTime of(int year, Month month, int dayOfMonth, int hour, int minute, int second, int nanoOfSecond) {
 286         LocalDate date = LocalDate.of(year, month, dayOfMonth);
 287         LocalTime time = LocalTime.of(hour, minute, second, nanoOfSecond);
 288         return new LocalDateTime(date, time);
 289     }
 290 
 291     //-----------------------------------------------------------------------
 292     /**
 293      * Obtains an instance of {@code LocalDateTime} from year, month,
 294      * day, hour and minute, setting the second and nanosecond to zero.
 295      * <p>
 296      * This returns a {@code LocalDateTime} with the specified year, month,
 297      * day-of-month, hour and minute.
 298      * The day must be valid for the year and month, otherwise an exception will be thrown.
 299      * The second and nanosecond fields will be set to zero.
 300      *
 301      * @param year  the year to represent, from MIN_YEAR to MAX_YEAR
 302      * @param month  the month-of-year to represent, from 1 (January) to 12 (December)
 303      * @param dayOfMonth  the day-of-month to represent, from 1 to 31
 304      * @param hour  the hour-of-day to represent, from 0 to 23
 305      * @param minute  the minute-of-hour to represent, from 0 to 59
 306      * @return the local date-time, not null
 307      * @throws DateTimeException if the value of any field is out of range,
 308      *  or if the day-of-month is invalid for the month-year
 309      */
 310     public static LocalDateTime of(int year, int month, int dayOfMonth, int hour, int minute) {
 311         LocalDate date = LocalDate.of(year, month, dayOfMonth);
 312         LocalTime time = LocalTime.of(hour, minute);
 313         return new LocalDateTime(date, time);
 314     }
 315 
 316     /**
 317      * Obtains an instance of {@code LocalDateTime} from year, month,
 318      * day, hour, minute and second, setting the nanosecond to zero.
 319      * <p>
 320      * This returns a {@code LocalDateTime} with the specified year, month,
 321      * day-of-month, hour, minute and second.
 322      * The day must be valid for the year and month, otherwise an exception will be thrown.
 323      * The nanosecond field will be set to zero.
 324      *
 325      * @param year  the year to represent, from MIN_YEAR to MAX_YEAR
 326      * @param month  the month-of-year to represent, from 1 (January) to 12 (December)
 327      * @param dayOfMonth  the day-of-month to represent, from 1 to 31
 328      * @param hour  the hour-of-day to represent, from 0 to 23
 329      * @param minute  the minute-of-hour to represent, from 0 to 59
 330      * @param second  the second-of-minute to represent, from 0 to 59
 331      * @return the local date-time, not null
 332      * @throws DateTimeException if the value of any field is out of range,
 333      *  or if the day-of-month is invalid for the month-year
 334      */
 335     public static LocalDateTime of(int year, int month, int dayOfMonth, int hour, int minute, int second) {
 336         LocalDate date = LocalDate.of(year, month, dayOfMonth);
 337         LocalTime time = LocalTime.of(hour, minute, second);
 338         return new LocalDateTime(date, time);
 339     }
 340 
 341     /**
 342      * Obtains an instance of {@code LocalDateTime} from year, month,
 343      * day, hour, minute, second and nanosecond.
 344      * <p>
 345      * This returns a {@code LocalDateTime} with the specified year, month,
 346      * day-of-month, hour, minute, second and nanosecond.
 347      * The day must be valid for the year and month, otherwise an exception will be thrown.
 348      *
 349      * @param year  the year to represent, from MIN_YEAR to MAX_YEAR
 350      * @param month  the month-of-year to represent, from 1 (January) to 12 (December)
 351      * @param dayOfMonth  the day-of-month to represent, from 1 to 31
 352      * @param hour  the hour-of-day to represent, from 0 to 23
 353      * @param minute  the minute-of-hour to represent, from 0 to 59
 354      * @param second  the second-of-minute to represent, from 0 to 59
 355      * @param nanoOfSecond  the nano-of-second to represent, from 0 to 999,999,999
 356      * @return the local date-time, not null
 357      * @throws DateTimeException if the value of any field is out of range,
 358      *  or if the day-of-month is invalid for the month-year
 359      */
 360     public static LocalDateTime of(int year, int month, int dayOfMonth, int hour, int minute, int second, int nanoOfSecond) {
 361         LocalDate date = LocalDate.of(year, month, dayOfMonth);
 362         LocalTime time = LocalTime.of(hour, minute, second, nanoOfSecond);
 363         return new LocalDateTime(date, time);
 364     }
 365 
 366     /**
 367      * Obtains an instance of {@code LocalDateTime} from a date and time.
 368      *
 369      * @param date  the local date, not null
 370      * @param time  the local time, not null
 371      * @return the local date-time, not null
 372      */
 373     public static LocalDateTime of(LocalDate date, LocalTime time) {
 374         Objects.requireNonNull(date, "date");
 375         Objects.requireNonNull(time, "time");
 376         return new LocalDateTime(date, time);
 377     }
 378 
 379     //-------------------------------------------------------------------------
 380     /**
 381      * Obtains an instance of {@code LocalDateTime} from an {@code Instant} and zone ID.
 382      * <p>
 383      * This creates a local date-time based on the specified instant.
 384      * First, the offset from UTC/Greenwich is obtained using the zone ID and instant,
 385      * which is simple as there is only one valid offset for each instant.
 386      * Then, the instant and offset are used to calculate the local date-time.
 387      *
 388      * @param instant  the instant to create the date-time from, not null
 389      * @param zone  the time-zone, which may be an offset, not null
 390      * @return the local date-time, not null
 391      * @throws DateTimeException if the result exceeds the supported range
 392      */
 393     public static LocalDateTime ofInstant(Instant instant, ZoneId zone) {
 394         Objects.requireNonNull(instant, "instant");
 395         Objects.requireNonNull(zone, "zone");
 396         ZoneRules rules = zone.getRules();
 397         ZoneOffset offset = rules.getOffset(instant);
 398         return ofEpochSecond(instant.getEpochSecond(), instant.getNano(), offset);
 399     }
 400 
 401     /**
 402      * Obtains an instance of {@code LocalDateTime} using seconds from the
 403      * epoch of 1970-01-01T00:00:00Z.
 404      * <p>
 405      * This allows the {@link ChronoField#INSTANT_SECONDS epoch-second} field
 406      * to be converted to a local date-time. This is primarily intended for
 407      * low-level conversions rather than general application usage.
 408      *
 409      * @param epochSecond  the number of seconds from the epoch of 1970-01-01T00:00:00Z
 410      * @param nanoOfSecond  the nanosecond within the second, from 0 to 999,999,999
 411      * @param offset  the zone offset, not null
 412      * @return the local date-time, not null
 413      * @throws DateTimeException if the result exceeds the supported range,
 414      *  or if the nano-of-second is invalid
 415      */
 416     public static LocalDateTime ofEpochSecond(long epochSecond, int nanoOfSecond, ZoneOffset offset) {
 417         Objects.requireNonNull(offset, "offset");
 418         NANO_OF_SECOND.checkValidValue(nanoOfSecond);
 419         long localSecond = epochSecond + offset.getTotalSeconds();  // overflow caught later
 420         long localEpochDay = Math.floorDiv(localSecond, SECONDS_PER_DAY);
 421         int secsOfDay = (int)Math.floorMod(localSecond, SECONDS_PER_DAY);
 422         LocalDate date = LocalDate.ofEpochDay(localEpochDay);
 423         LocalTime time = LocalTime.ofNanoOfDay(secsOfDay * NANOS_PER_SECOND + nanoOfSecond);
 424         return new LocalDateTime(date, time);
 425     }
 426 
 427     //-----------------------------------------------------------------------
 428     /**
 429      * Obtains an instance of {@code LocalDateTime} from a temporal object.
 430      * <p>
 431      * This obtains a local date-time based on the specified temporal.
 432      * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
 433      * which this factory converts to an instance of {@code LocalDateTime}.
 434      * <p>
 435      * The conversion extracts and combines the {@code LocalDate} and the
 436      * {@code LocalTime} from the temporal object.
 437      * Implementations are permitted to perform optimizations such as accessing
 438      * those fields that are equivalent to the relevant objects.
 439      * <p>
 440      * This method matches the signature of the functional interface {@link TemporalQuery}
 441      * allowing it to be used as a query via method reference, {@code LocalDateTime::from}.
 442      *
 443      * @param temporal  the temporal object to convert, not null
 444      * @return the local date-time, not null
 445      * @throws DateTimeException if unable to convert to a {@code LocalDateTime}
 446      */
 447     public static LocalDateTime from(TemporalAccessor temporal) {
 448         if (temporal instanceof LocalDateTime) {
 449             return (LocalDateTime) temporal;
 450         } else if (temporal instanceof ZonedDateTime) {
 451             return ((ZonedDateTime) temporal).toLocalDateTime();
 452         } else if (temporal instanceof OffsetDateTime) {
 453             return ((OffsetDateTime) temporal).toLocalDateTime();
 454         }
 455         try {
 456             LocalDate date = LocalDate.from(temporal);
 457             LocalTime time = LocalTime.from(temporal);
 458             return new LocalDateTime(date, time);
 459         } catch (DateTimeException ex) {
 460             throw new DateTimeException("Unable to obtain LocalDateTime from TemporalAccessor: " +
 461                     temporal + " of type " + temporal.getClass().getName(), ex);
 462         }
 463     }
 464 
 465     //-----------------------------------------------------------------------
 466     /**
 467      * Obtains an instance of {@code LocalDateTime} from a text string such as {@code 2007-12-03T10:15:30}.
 468      * <p>
 469      * The string must represent a valid date-time and is parsed using
 470      * {@link java.time.format.DateTimeFormatter#ISO_LOCAL_DATE_TIME}.
 471      *
 472      * @param text  the text to parse such as "2007-12-03T10:15:30", not null
 473      * @return the parsed local date-time, not null
 474      * @throws DateTimeParseException if the text cannot be parsed
 475      */
 476     public static LocalDateTime parse(CharSequence text) {
 477         return parse(text, DateTimeFormatter.ISO_LOCAL_DATE_TIME);
 478     }
 479 
 480     /**
 481      * Obtains an instance of {@code LocalDateTime} from a text string using a specific formatter.
 482      * <p>
 483      * The text is parsed using the formatter, returning a date-time.
 484      *
 485      * @param text  the text to parse, not null
 486      * @param formatter  the formatter to use, not null
 487      * @return the parsed local date-time, not null
 488      * @throws DateTimeParseException if the text cannot be parsed
 489      */
 490     public static LocalDateTime parse(CharSequence text, DateTimeFormatter formatter) {
 491         Objects.requireNonNull(formatter, "formatter");
 492         return formatter.parse(text, LocalDateTime::from);
 493     }
 494 
 495     //-----------------------------------------------------------------------
 496     /**
 497      * Constructor.
 498      *
 499      * @param date  the date part of the date-time, validated not null
 500      * @param time  the time part of the date-time, validated not null
 501      */
 502     private LocalDateTime(LocalDate date, LocalTime time) {
 503         this.date = date;
 504         this.time = time;
 505     }
 506 
 507     /**
 508      * Returns a copy of this date-time with the new date and time, checking
 509      * to see if a new object is in fact required.
 510      *
 511      * @param newDate  the date of the new date-time, not null
 512      * @param newTime  the time of the new date-time, not null
 513      * @return the date-time, not null
 514      */
 515     private LocalDateTime with(LocalDate newDate, LocalTime newTime) {
 516         if (date == newDate && time == newTime) {
 517             return this;
 518         }
 519         return new LocalDateTime(newDate, newTime);
 520     }
 521 
 522     //-----------------------------------------------------------------------
 523     /**
 524      * Checks if the specified field is supported.
 525      * <p>
 526      * This checks if this date-time can be queried for the specified field.
 527      * If false, then calling the {@link #range(TemporalField) range},
 528      * {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
 529      * methods will throw an exception.
 530      * <p>
 531      * If the field is a {@link ChronoField} then the query is implemented here.
 532      * The supported fields are:
 533      * <ul>
 534      * <li>{@code NANO_OF_SECOND}
 535      * <li>{@code NANO_OF_DAY}
 536      * <li>{@code MICRO_OF_SECOND}
 537      * <li>{@code MICRO_OF_DAY}
 538      * <li>{@code MILLI_OF_SECOND}
 539      * <li>{@code MILLI_OF_DAY}
 540      * <li>{@code SECOND_OF_MINUTE}
 541      * <li>{@code SECOND_OF_DAY}
 542      * <li>{@code MINUTE_OF_HOUR}
 543      * <li>{@code MINUTE_OF_DAY}
 544      * <li>{@code HOUR_OF_AMPM}
 545      * <li>{@code CLOCK_HOUR_OF_AMPM}
 546      * <li>{@code HOUR_OF_DAY}
 547      * <li>{@code CLOCK_HOUR_OF_DAY}
 548      * <li>{@code AMPM_OF_DAY}
 549      * <li>{@code DAY_OF_WEEK}
 550      * <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH}
 551      * <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR}
 552      * <li>{@code DAY_OF_MONTH}
 553      * <li>{@code DAY_OF_YEAR}
 554      * <li>{@code EPOCH_DAY}
 555      * <li>{@code ALIGNED_WEEK_OF_MONTH}
 556      * <li>{@code ALIGNED_WEEK_OF_YEAR}
 557      * <li>{@code MONTH_OF_YEAR}
 558      * <li>{@code PROLEPTIC_MONTH}
 559      * <li>{@code YEAR_OF_ERA}
 560      * <li>{@code YEAR}
 561      * <li>{@code ERA}
 562      * </ul>
 563      * All other {@code ChronoField} instances will return false.
 564      * <p>
 565      * If the field is not a {@code ChronoField}, then the result of this method
 566      * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
 567      * passing {@code this} as the argument.
 568      * Whether the field is supported is determined by the field.
 569      *
 570      * @param field  the field to check, null returns false
 571      * @return true if the field is supported on this date-time, false if not
 572      */
 573     @Override
 574     public boolean isSupported(TemporalField field) {
 575         if (field instanceof ChronoField) {
 576             ChronoField f = (ChronoField) field;
 577             return f.isDateBased() || f.isTimeBased();
 578         }
 579         return field != null && field.isSupportedBy(this);
 580     }
 581 
 582     /**
 583      * Checks if the specified unit is supported.
 584      * <p>
 585      * This checks if the specified unit can be added to, or subtracted from, this date-time.
 586      * If false, then calling the {@link #plus(long, TemporalUnit)} and
 587      * {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
 588      * <p>
 589      * If the unit is a {@link ChronoUnit} then the query is implemented here.
 590      * The supported units are:
 591      * <ul>
 592      * <li>{@code NANOS}
 593      * <li>{@code MICROS}
 594      * <li>{@code MILLIS}
 595      * <li>{@code SECONDS}
 596      * <li>{@code MINUTES}
 597      * <li>{@code HOURS}
 598      * <li>{@code HALF_DAYS}
 599      * <li>{@code DAYS}
 600      * <li>{@code WEEKS}
 601      * <li>{@code MONTHS}
 602      * <li>{@code YEARS}
 603      * <li>{@code DECADES}
 604      * <li>{@code CENTURIES}
 605      * <li>{@code MILLENNIA}
 606      * <li>{@code ERAS}
 607      * </ul>
 608      * All other {@code ChronoUnit} instances will return false.
 609      * <p>
 610      * If the unit is not a {@code ChronoUnit}, then the result of this method
 611      * is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
 612      * passing {@code this} as the argument.
 613      * Whether the unit is supported is determined by the unit.
 614      *
 615      * @param unit  the unit to check, null returns false
 616      * @return true if the unit can be added/subtracted, false if not
 617      */
 618     @Override  // override for Javadoc
 619     public boolean isSupported(TemporalUnit unit) {
 620         return ChronoLocalDateTime.super.isSupported(unit);
 621     }
 622 
 623     //-----------------------------------------------------------------------
 624     /**
 625      * Gets the range of valid values for the specified field.
 626      * <p>
 627      * The range object expresses the minimum and maximum valid values for a field.
 628      * This date-time is used to enhance the accuracy of the returned range.
 629      * If it is not possible to return the range, because the field is not supported
 630      * or for some other reason, an exception is thrown.
 631      * <p>
 632      * If the field is a {@link ChronoField} then the query is implemented here.
 633      * The {@link #isSupported(TemporalField) supported fields} will return
 634      * appropriate range instances.
 635      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 636      * <p>
 637      * If the field is not a {@code ChronoField}, then the result of this method
 638      * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
 639      * passing {@code this} as the argument.
 640      * Whether the range can be obtained is determined by the field.
 641      *
 642      * @param field  the field to query the range for, not null
 643      * @return the range of valid values for the field, not null
 644      * @throws DateTimeException if the range for the field cannot be obtained
 645      * @throws UnsupportedTemporalTypeException if the field is not supported
 646      */
 647     @Override
 648     public ValueRange range(TemporalField field) {
 649         if (field instanceof ChronoField) {
 650             ChronoField f = (ChronoField) field;
 651             return (f.isTimeBased() ? time.range(field) : date.range(field));
 652         }
 653         return field.rangeRefinedBy(this);
 654     }
 655 
 656     /**
 657      * Gets the value of the specified field from this date-time as an {@code int}.
 658      * <p>
 659      * This queries this date-time for the value of the specified field.
 660      * The returned value will always be within the valid range of values for the field.
 661      * If it is not possible to return the value, because the field is not supported
 662      * or for some other reason, an exception is thrown.
 663      * <p>
 664      * If the field is a {@link ChronoField} then the query is implemented here.
 665      * The {@link #isSupported(TemporalField) supported fields} will return valid
 666      * values based on this date-time, except {@code NANO_OF_DAY}, {@code MICRO_OF_DAY},
 667      * {@code EPOCH_DAY} and {@code PROLEPTIC_MONTH} which are too large to fit in
 668      * an {@code int} and throw a {@code UnsupportedTemporalTypeException}.
 669      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 670      * <p>
 671      * If the field is not a {@code ChronoField}, then the result of this method
 672      * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
 673      * passing {@code this} as the argument. Whether the value can be obtained,
 674      * and what the value represents, is determined by the field.
 675      *
 676      * @param field  the field to get, not null
 677      * @return the value for the field
 678      * @throws DateTimeException if a value for the field cannot be obtained or
 679      *         the value is outside the range of valid values for the field
 680      * @throws UnsupportedTemporalTypeException if the field is not supported or
 681      *         the range of values exceeds an {@code int}
 682      * @throws ArithmeticException if numeric overflow occurs
 683      */
 684     @Override
 685     public int get(TemporalField field) {
 686         if (field instanceof ChronoField) {
 687             ChronoField f = (ChronoField) field;
 688             return (f.isTimeBased() ? time.get(field) : date.get(field));
 689         }
 690         return ChronoLocalDateTime.super.get(field);
 691     }
 692 
 693     /**
 694      * Gets the value of the specified field from this date-time as a {@code long}.
 695      * <p>
 696      * This queries this date-time for the value of the specified field.
 697      * If it is not possible to return the value, because the field is not supported
 698      * or for some other reason, an exception is thrown.
 699      * <p>
 700      * If the field is a {@link ChronoField} then the query is implemented here.
 701      * The {@link #isSupported(TemporalField) supported fields} will return valid
 702      * values based on this date-time.
 703      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 704      * <p>
 705      * If the field is not a {@code ChronoField}, then the result of this method
 706      * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
 707      * passing {@code this} as the argument. Whether the value can be obtained,
 708      * and what the value represents, is determined by the field.
 709      *
 710      * @param field  the field to get, not null
 711      * @return the value for the field
 712      * @throws DateTimeException if a value for the field cannot be obtained
 713      * @throws UnsupportedTemporalTypeException if the field is not supported
 714      * @throws ArithmeticException if numeric overflow occurs
 715      */
 716     @Override
 717     public long getLong(TemporalField field) {
 718         if (field instanceof ChronoField) {
 719             ChronoField f = (ChronoField) field;
 720             return (f.isTimeBased() ? time.getLong(field) : date.getLong(field));
 721         }
 722         return field.getFrom(this);
 723     }
 724 
 725     //-----------------------------------------------------------------------
 726     /**
 727      * Gets the {@code LocalDate} part of this date-time.
 728      * <p>
 729      * This returns a {@code LocalDate} with the same year, month and day
 730      * as this date-time.
 731      *
 732      * @return the date part of this date-time, not null
 733      */
 734     @Override
 735     public LocalDate toLocalDate() {
 736         return date;
 737     }
 738 
 739     /**
 740      * Gets the year field.
 741      * <p>
 742      * This method returns the primitive {@code int} value for the year.
 743      * <p>
 744      * The year returned by this method is proleptic as per {@code get(YEAR)}.
 745      * To obtain the year-of-era, use {@code get(YEAR_OF_ERA)}.
 746      *
 747      * @return the year, from MIN_YEAR to MAX_YEAR
 748      */
 749     public int getYear() {
 750         return date.getYear();
 751     }
 752 
 753     /**
 754      * Gets the month-of-year field from 1 to 12.
 755      * <p>
 756      * This method returns the month as an {@code int} from 1 to 12.
 757      * Application code is frequently clearer if the enum {@link Month}
 758      * is used by calling {@link #getMonth()}.
 759      *
 760      * @return the month-of-year, from 1 to 12
 761      * @see #getMonth()
 762      */
 763     public int getMonthValue() {
 764         return date.getMonthValue();
 765     }
 766 
 767     /**
 768      * Gets the month-of-year field using the {@code Month} enum.
 769      * <p>
 770      * This method returns the enum {@link Month} for the month.
 771      * This avoids confusion as to what {@code int} values mean.
 772      * If you need access to the primitive {@code int} value then the enum
 773      * provides the {@link Month#getValue() int value}.
 774      *
 775      * @return the month-of-year, not null
 776      * @see #getMonthValue()
 777      */
 778     public Month getMonth() {
 779         return date.getMonth();
 780     }
 781 
 782     /**
 783      * Gets the day-of-month field.
 784      * <p>
 785      * This method returns the primitive {@code int} value for the day-of-month.
 786      *
 787      * @return the day-of-month, from 1 to 31
 788      */
 789     public int getDayOfMonth() {
 790         return date.getDayOfMonth();
 791     }
 792 
 793     /**
 794      * Gets the day-of-year field.
 795      * <p>
 796      * This method returns the primitive {@code int} value for the day-of-year.
 797      *
 798      * @return the day-of-year, from 1 to 365, or 366 in a leap year
 799      */
 800     public int getDayOfYear() {
 801         return date.getDayOfYear();
 802     }
 803 
 804     /**
 805      * Gets the day-of-week field, which is an enum {@code DayOfWeek}.
 806      * <p>
 807      * This method returns the enum {@link DayOfWeek} for the day-of-week.
 808      * This avoids confusion as to what {@code int} values mean.
 809      * If you need access to the primitive {@code int} value then the enum
 810      * provides the {@link DayOfWeek#getValue() int value}.
 811      * <p>
 812      * Additional information can be obtained from the {@code DayOfWeek}.
 813      * This includes textual names of the values.
 814      *
 815      * @return the day-of-week, not null
 816      */
 817     public DayOfWeek getDayOfWeek() {
 818         return date.getDayOfWeek();
 819     }
 820 
 821     //-----------------------------------------------------------------------
 822     /**
 823      * Gets the {@code LocalTime} part of this date-time.
 824      * <p>
 825      * This returns a {@code LocalTime} with the same hour, minute, second and
 826      * nanosecond as this date-time.
 827      *
 828      * @return the time part of this date-time, not null
 829      */
 830     @Override
 831     public LocalTime toLocalTime() {
 832         return time;
 833     }
 834 
 835     /**
 836      * Gets the hour-of-day field.
 837      *
 838      * @return the hour-of-day, from 0 to 23
 839      */
 840     public int getHour() {
 841         return time.getHour();
 842     }
 843 
 844     /**
 845      * Gets the minute-of-hour field.
 846      *
 847      * @return the minute-of-hour, from 0 to 59
 848      */
 849     public int getMinute() {
 850         return time.getMinute();
 851     }
 852 
 853     /**
 854      * Gets the second-of-minute field.
 855      *
 856      * @return the second-of-minute, from 0 to 59
 857      */
 858     public int getSecond() {
 859         return time.getSecond();
 860     }
 861 
 862     /**
 863      * Gets the nano-of-second field.
 864      *
 865      * @return the nano-of-second, from 0 to 999,999,999
 866      */
 867     public int getNano() {
 868         return time.getNano();
 869     }
 870 
 871     //-----------------------------------------------------------------------
 872     /**
 873      * Returns an adjusted copy of this date-time.
 874      * <p>
 875      * This returns a {@code LocalDateTime}, based on this one, with the date-time adjusted.
 876      * The adjustment takes place using the specified adjuster strategy object.
 877      * Read the documentation of the adjuster to understand what adjustment will be made.
 878      * <p>
 879      * A simple adjuster might simply set the one of the fields, such as the year field.
 880      * A more complex adjuster might set the date to the last day of the month.
 881      * <p>
 882      * A selection of common adjustments is provided in
 883      * {@link java.time.temporal.TemporalAdjusters TemporalAdjusters}.
 884      * These include finding the "last day of the month" and "next Wednesday".
 885      * Key date-time classes also implement the {@code TemporalAdjuster} interface,
 886      * such as {@link Month} and {@link java.time.MonthDay MonthDay}.
 887      * The adjuster is responsible for handling special cases, such as the varying
 888      * lengths of month and leap years.
 889      * <p>
 890      * For example this code returns a date on the last day of July:
 891      * <pre>
 892      *  import static java.time.Month.*;
 893      *  import static java.time.temporal.TemporalAdjusters.*;
 894      *
 895      *  result = localDateTime.with(JULY).with(lastDayOfMonth());
 896      * </pre>
 897      * <p>
 898      * The classes {@link LocalDate} and {@link LocalTime} implement {@code TemporalAdjuster},
 899      * thus this method can be used to change the date, time or offset:
 900      * <pre>
 901      *  result = localDateTime.with(date);
 902      *  result = localDateTime.with(time);
 903      * </pre>
 904      * <p>
 905      * The result of this method is obtained by invoking the
 906      * {@link TemporalAdjuster#adjustInto(Temporal)} method on the
 907      * specified adjuster passing {@code this} as the argument.
 908      * <p>
 909      * This instance is immutable and unaffected by this method call.
 910      *
 911      * @param adjuster the adjuster to use, not null
 912      * @return a {@code LocalDateTime} based on {@code this} with the adjustment made, not null
 913      * @throws DateTimeException if the adjustment cannot be made
 914      * @throws ArithmeticException if numeric overflow occurs
 915      */
 916     @Override
 917     public LocalDateTime with(TemporalAdjuster adjuster) {
 918         // optimizations
 919         if (adjuster instanceof LocalDate) {
 920             return with((LocalDate) adjuster, time);
 921         } else if (adjuster instanceof LocalTime) {
 922             return with(date, (LocalTime) adjuster);
 923         } else if (adjuster instanceof LocalDateTime) {
 924             return (LocalDateTime) adjuster;
 925         }
 926         return (LocalDateTime) adjuster.adjustInto(this);
 927     }
 928 
 929     /**
 930      * Returns a copy of this date-time with the specified field set to a new value.
 931      * <p>
 932      * This returns a {@code LocalDateTime}, based on this one, with the value
 933      * for the specified field changed.
 934      * This can be used to change any supported field, such as the year, month or day-of-month.
 935      * If it is not possible to set the value, because the field is not supported or for
 936      * some other reason, an exception is thrown.
 937      * <p>
 938      * In some cases, changing the specified field can cause the resulting date-time to become invalid,
 939      * such as changing the month from 31st January to February would make the day-of-month invalid.
 940      * In cases like this, the field is responsible for resolving the date. Typically it will choose
 941      * the previous valid date, which would be the last valid day of February in this example.
 942      * <p>
 943      * If the field is a {@link ChronoField} then the adjustment is implemented here.
 944      * The {@link #isSupported(TemporalField) supported fields} will behave as per
 945      * the matching method on {@link LocalDate#with(TemporalField, long) LocalDate}
 946      * or {@link LocalTime#with(TemporalField, long) LocalTime}.
 947      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 948      * <p>
 949      * If the field is not a {@code ChronoField}, then the result of this method
 950      * is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
 951      * passing {@code this} as the argument. In this case, the field determines
 952      * whether and how to adjust the instant.
 953      * <p>
 954      * This instance is immutable and unaffected by this method call.
 955      *
 956      * @param field  the field to set in the result, not null
 957      * @param newValue  the new value of the field in the result
 958      * @return a {@code LocalDateTime} based on {@code this} with the specified field set, not null
 959      * @throws DateTimeException if the field cannot be set
 960      * @throws UnsupportedTemporalTypeException if the field is not supported
 961      * @throws ArithmeticException if numeric overflow occurs
 962      */
 963     @Override
 964     public LocalDateTime with(TemporalField field, long newValue) {
 965         if (field instanceof ChronoField) {
 966             ChronoField f = (ChronoField) field;
 967             if (f.isTimeBased()) {
 968                 return with(date, time.with(field, newValue));
 969             } else {
 970                 return with(date.with(field, newValue), time);
 971             }
 972         }
 973         return field.adjustInto(this, newValue);
 974     }
 975 
 976     //-----------------------------------------------------------------------
 977     /**
 978      * Returns a copy of this {@code LocalDateTime} with the year altered.
 979      * <p>
 980      * The time does not affect the calculation and will be the same in the result.
 981      * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
 982      * <p>
 983      * This instance is immutable and unaffected by this method call.
 984      *
 985      * @param year  the year to set in the result, from MIN_YEAR to MAX_YEAR
 986      * @return a {@code LocalDateTime} based on this date-time with the requested year, not null
 987      * @throws DateTimeException if the year value is invalid
 988      */
 989     public LocalDateTime withYear(int year) {
 990         return with(date.withYear(year), time);
 991     }
 992 
 993     /**
 994      * Returns a copy of this {@code LocalDateTime} with the month-of-year altered.
 995      * <p>
 996      * The time does not affect the calculation and will be the same in the result.
 997      * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
 998      * <p>
 999      * This instance is immutable and unaffected by this method call.
1000      *
1001      * @param month  the month-of-year to set in the result, from 1 (January) to 12 (December)
1002      * @return a {@code LocalDateTime} based on this date-time with the requested month, not null
1003      * @throws DateTimeException if the month-of-year value is invalid
1004      */
1005     public LocalDateTime withMonth(int month) {
1006         return with(date.withMonth(month), time);
1007     }
1008 
1009     /**
1010      * Returns a copy of this {@code LocalDateTime} with the day-of-month altered.
1011      * <p>
1012      * If the resulting date-time is invalid, an exception is thrown.
1013      * The time does not affect the calculation and will be the same in the result.
1014      * <p>
1015      * This instance is immutable and unaffected by this method call.
1016      *
1017      * @param dayOfMonth  the day-of-month to set in the result, from 1 to 28-31
1018      * @return a {@code LocalDateTime} based on this date-time with the requested day, not null
1019      * @throws DateTimeException if the day-of-month value is invalid,
1020      *  or if the day-of-month is invalid for the month-year
1021      */
1022     public LocalDateTime withDayOfMonth(int dayOfMonth) {
1023         return with(date.withDayOfMonth(dayOfMonth), time);
1024     }
1025 
1026     /**
1027      * Returns a copy of this {@code LocalDateTime} with the day-of-year altered.
1028      * <p>
1029      * If the resulting date-time is invalid, an exception is thrown.
1030      * <p>
1031      * This instance is immutable and unaffected by this method call.
1032      *
1033      * @param dayOfYear  the day-of-year to set in the result, from 1 to 365-366
1034      * @return a {@code LocalDateTime} based on this date with the requested day, not null
1035      * @throws DateTimeException if the day-of-year value is invalid,
1036      *  or if the day-of-year is invalid for the year
1037      */
1038     public LocalDateTime withDayOfYear(int dayOfYear) {
1039         return with(date.withDayOfYear(dayOfYear), time);
1040     }
1041 
1042     //-----------------------------------------------------------------------
1043     /**
1044      * Returns a copy of this {@code LocalDateTime} with the hour-of-day altered.
1045      * <p>
1046      * This instance is immutable and unaffected by this method call.
1047      *
1048      * @param hour  the hour-of-day to set in the result, from 0 to 23
1049      * @return a {@code LocalDateTime} based on this date-time with the requested hour, not null
1050      * @throws DateTimeException if the hour value is invalid
1051      */
1052     public LocalDateTime withHour(int hour) {
1053         LocalTime newTime = time.withHour(hour);
1054         return with(date, newTime);
1055     }
1056 
1057     /**
1058      * Returns a copy of this {@code LocalDateTime} with the minute-of-hour altered.
1059      * <p>
1060      * This instance is immutable and unaffected by this method call.
1061      *
1062      * @param minute  the minute-of-hour to set in the result, from 0 to 59
1063      * @return a {@code LocalDateTime} based on this date-time with the requested minute, not null
1064      * @throws DateTimeException if the minute value is invalid
1065      */
1066     public LocalDateTime withMinute(int minute) {
1067         LocalTime newTime = time.withMinute(minute);
1068         return with(date, newTime);
1069     }
1070 
1071     /**
1072      * Returns a copy of this {@code LocalDateTime} with the second-of-minute altered.
1073      * <p>
1074      * This instance is immutable and unaffected by this method call.
1075      *
1076      * @param second  the second-of-minute to set in the result, from 0 to 59
1077      * @return a {@code LocalDateTime} based on this date-time with the requested second, not null
1078      * @throws DateTimeException if the second value is invalid
1079      */
1080     public LocalDateTime withSecond(int second) {
1081         LocalTime newTime = time.withSecond(second);
1082         return with(date, newTime);
1083     }
1084 
1085     /**
1086      * Returns a copy of this {@code LocalDateTime} with the nano-of-second altered.
1087      * <p>
1088      * This instance is immutable and unaffected by this method call.
1089      *
1090      * @param nanoOfSecond  the nano-of-second to set in the result, from 0 to 999,999,999
1091      * @return a {@code LocalDateTime} based on this date-time with the requested nanosecond, not null
1092      * @throws DateTimeException if the nano value is invalid
1093      */
1094     public LocalDateTime withNano(int nanoOfSecond) {
1095         LocalTime newTime = time.withNano(nanoOfSecond);
1096         return with(date, newTime);
1097     }
1098 
1099     //-----------------------------------------------------------------------
1100     /**
1101      * Returns a copy of this {@code LocalDateTime} with the time truncated.
1102      * <p>
1103      * Truncation returns a copy of the original date-time with fields
1104      * smaller than the specified unit set to zero.
1105      * For example, truncating with the {@link ChronoUnit#MINUTES minutes} unit
1106      * will set the second-of-minute and nano-of-second field to zero.
1107      * <p>
1108      * The unit must have a {@linkplain TemporalUnit#getDuration() duration}
1109      * that divides into the length of a standard day without remainder.
1110      * This includes all supplied time units on {@link ChronoUnit} and
1111      * {@link ChronoUnit#DAYS DAYS}. Other units throw an exception.
1112      * <p>
1113      * This instance is immutable and unaffected by this method call.
1114      *
1115      * @param unit  the unit to truncate to, not null
1116      * @return a {@code LocalDateTime} based on this date-time with the time truncated, not null
1117      * @throws DateTimeException if unable to truncate
1118      * @throws UnsupportedTemporalTypeException if the unit is not supported
1119      */
1120     public LocalDateTime truncatedTo(TemporalUnit unit) {
1121         return with(date, time.truncatedTo(unit));
1122     }
1123 
1124     //-----------------------------------------------------------------------
1125     /**
1126      * Returns a copy of this date-time with the specified amount added.
1127      * <p>
1128      * This returns a {@code LocalDateTime}, based on this one, with the specified amount added.
1129      * The amount is typically {@link Period} or {@link Duration} but may be
1130      * any other type implementing the {@link TemporalAmount} interface.
1131      * <p>
1132      * The calculation is delegated to the amount object by calling
1133      * {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
1134      * to implement the addition in any way it wishes, however it typically
1135      * calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
1136      * of the amount implementation to determine if it can be successfully added.
1137      * <p>
1138      * This instance is immutable and unaffected by this method call.
1139      *
1140      * @param amountToAdd  the amount to add, not null
1141      * @return a {@code LocalDateTime} based on this date-time with the addition made, not null
1142      * @throws DateTimeException if the addition cannot be made
1143      * @throws ArithmeticException if numeric overflow occurs
1144      */
1145     @Override
1146     public LocalDateTime plus(TemporalAmount amountToAdd) {
1147         if (amountToAdd instanceof Period) {
1148             Period periodToAdd = (Period) amountToAdd;
1149             return with(date.plus(periodToAdd), time);
1150         }
1151         Objects.requireNonNull(amountToAdd, "amountToAdd");
1152         return (LocalDateTime) amountToAdd.addTo(this);
1153     }
1154 
1155     /**
1156      * Returns a copy of this date-time with the specified amount added.
1157      * <p>
1158      * This returns a {@code LocalDateTime}, based on this one, with the amount
1159      * in terms of the unit added. If it is not possible to add the amount, because the
1160      * unit is not supported or for some other reason, an exception is thrown.
1161      * <p>
1162      * If the field is a {@link ChronoUnit} then the addition is implemented here.
1163      * Date units are added as per {@link LocalDate#plus(long, TemporalUnit)}.
1164      * Time units are added as per {@link LocalTime#plus(long, TemporalUnit)} with
1165      * any overflow in days added equivalent to using {@link #plusDays(long)}.
1166      * <p>
1167      * If the field is not a {@code ChronoUnit}, then the result of this method
1168      * is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
1169      * passing {@code this} as the argument. In this case, the unit determines
1170      * whether and how to perform the addition.
1171      * <p>
1172      * This instance is immutable and unaffected by this method call.
1173      *
1174      * @param amountToAdd  the amount of the unit to add to the result, may be negative
1175      * @param unit  the unit of the amount to add, not null
1176      * @return a {@code LocalDateTime} based on this date-time with the specified amount added, not null
1177      * @throws DateTimeException if the addition cannot be made
1178      * @throws UnsupportedTemporalTypeException if the unit is not supported
1179      * @throws ArithmeticException if numeric overflow occurs
1180      */
1181     @Override
1182     public LocalDateTime plus(long amountToAdd, TemporalUnit unit) {
1183         if (unit instanceof ChronoUnit) {
1184             ChronoUnit f = (ChronoUnit) unit;
1185             switch (f) {
1186                 case NANOS: return plusNanos(amountToAdd);
1187                 case MICROS: return plusDays(amountToAdd / MICROS_PER_DAY).plusNanos((amountToAdd % MICROS_PER_DAY) * 1000);
1188                 case MILLIS: return plusDays(amountToAdd / MILLIS_PER_DAY).plusNanos((amountToAdd % MILLIS_PER_DAY) * 1000_000);
1189                 case SECONDS: return plusSeconds(amountToAdd);
1190                 case MINUTES: return plusMinutes(amountToAdd);
1191                 case HOURS: return plusHours(amountToAdd);
1192                 case HALF_DAYS: return plusDays(amountToAdd / 256).plusHours((amountToAdd % 256) * 12);  // no overflow (256 is multiple of 2)
1193             }
1194             return with(date.plus(amountToAdd, unit), time);
1195         }
1196         return unit.addTo(this, amountToAdd);
1197     }
1198 
1199     //-----------------------------------------------------------------------
1200     /**
1201      * Returns a copy of this {@code LocalDateTime} with the specified number of years added.
1202      * <p>
1203      * This method adds the specified amount to the years field in three steps:
1204      * <ol>
1205      * <li>Add the input years to the year field</li>
1206      * <li>Check if the resulting date would be invalid</li>
1207      * <li>Adjust the day-of-month to the last valid day if necessary</li>
1208      * </ol>
1209      * <p>
1210      * For example, 2008-02-29 (leap year) plus one year would result in the
1211      * invalid date 2009-02-29 (standard year). Instead of returning an invalid
1212      * result, the last valid day of the month, 2009-02-28, is selected instead.
1213      * <p>
1214      * This instance is immutable and unaffected by this method call.
1215      *
1216      * @param years  the years to add, may be negative
1217      * @return a {@code LocalDateTime} based on this date-time with the years added, not null
1218      * @throws DateTimeException if the result exceeds the supported date range
1219      */
1220     public LocalDateTime plusYears(long years) {
1221         LocalDate newDate = date.plusYears(years);
1222         return with(newDate, time);
1223     }
1224 
1225     /**
1226      * Returns a copy of this {@code LocalDateTime} with the specified number of months added.
1227      * <p>
1228      * This method adds the specified amount to the months field in three steps:
1229      * <ol>
1230      * <li>Add the input months to the month-of-year field</li>
1231      * <li>Check if the resulting date would be invalid</li>
1232      * <li>Adjust the day-of-month to the last valid day if necessary</li>
1233      * </ol>
1234      * <p>
1235      * For example, 2007-03-31 plus one month would result in the invalid date
1236      * 2007-04-31. Instead of returning an invalid result, the last valid day
1237      * of the month, 2007-04-30, is selected instead.
1238      * <p>
1239      * This instance is immutable and unaffected by this method call.
1240      *
1241      * @param months  the months to add, may be negative
1242      * @return a {@code LocalDateTime} based on this date-time with the months added, not null
1243      * @throws DateTimeException if the result exceeds the supported date range
1244      */
1245     public LocalDateTime plusMonths(long months) {
1246         LocalDate newDate = date.plusMonths(months);
1247         return with(newDate, time);
1248     }
1249 
1250     /**
1251      * Returns a copy of this {@code LocalDateTime} with the specified number of weeks added.
1252      * <p>
1253      * This method adds the specified amount in weeks to the days field incrementing
1254      * the month and year fields as necessary to ensure the result remains valid.
1255      * The result is only invalid if the maximum/minimum year is exceeded.
1256      * <p>
1257      * For example, 2008-12-31 plus one week would result in 2009-01-07.
1258      * <p>
1259      * This instance is immutable and unaffected by this method call.
1260      *
1261      * @param weeks  the weeks to add, may be negative
1262      * @return a {@code LocalDateTime} based on this date-time with the weeks added, not null
1263      * @throws DateTimeException if the result exceeds the supported date range
1264      */
1265     public LocalDateTime plusWeeks(long weeks) {
1266         LocalDate newDate = date.plusWeeks(weeks);
1267         return with(newDate, time);
1268     }
1269 
1270     /**
1271      * Returns a copy of this {@code LocalDateTime} with the specified number of days added.
1272      * <p>
1273      * This method adds the specified amount to the days field incrementing the
1274      * month and year fields as necessary to ensure the result remains valid.
1275      * The result is only invalid if the maximum/minimum year is exceeded.
1276      * <p>
1277      * For example, 2008-12-31 plus one day would result in 2009-01-01.
1278      * <p>
1279      * This instance is immutable and unaffected by this method call.
1280      *
1281      * @param days  the days to add, may be negative
1282      * @return a {@code LocalDateTime} based on this date-time with the days added, not null
1283      * @throws DateTimeException if the result exceeds the supported date range
1284      */
1285     public LocalDateTime plusDays(long days) {
1286         LocalDate newDate = date.plusDays(days);
1287         return with(newDate, time);
1288     }
1289 
1290     //-----------------------------------------------------------------------
1291     /**
1292      * Returns a copy of this {@code LocalDateTime} with the specified number of hours added.
1293      * <p>
1294      * This instance is immutable and unaffected by this method call.
1295      *
1296      * @param hours  the hours to add, may be negative
1297      * @return a {@code LocalDateTime} based on this date-time with the hours added, not null
1298      * @throws DateTimeException if the result exceeds the supported date range
1299      */
1300     public LocalDateTime plusHours(long hours) {
1301         return plusWithOverflow(date, hours, 0, 0, 0, 1);
1302     }
1303 
1304     /**
1305      * Returns a copy of this {@code LocalDateTime} with the specified number of minutes added.
1306      * <p>
1307      * This instance is immutable and unaffected by this method call.
1308      *
1309      * @param minutes  the minutes to add, may be negative
1310      * @return a {@code LocalDateTime} based on this date-time with the minutes added, not null
1311      * @throws DateTimeException if the result exceeds the supported date range
1312      */
1313     public LocalDateTime plusMinutes(long minutes) {
1314         return plusWithOverflow(date, 0, minutes, 0, 0, 1);
1315     }
1316 
1317     /**
1318      * Returns a copy of this {@code LocalDateTime} with the specified number of seconds added.
1319      * <p>
1320      * This instance is immutable and unaffected by this method call.
1321      *
1322      * @param seconds  the seconds to add, may be negative
1323      * @return a {@code LocalDateTime} based on this date-time with the seconds added, not null
1324      * @throws DateTimeException if the result exceeds the supported date range
1325      */
1326     public LocalDateTime plusSeconds(long seconds) {
1327         return plusWithOverflow(date, 0, 0, seconds, 0, 1);
1328     }
1329 
1330     /**
1331      * Returns a copy of this {@code LocalDateTime} with the specified number of nanoseconds added.
1332      * <p>
1333      * This instance is immutable and unaffected by this method call.
1334      *
1335      * @param nanos  the nanos to add, may be negative
1336      * @return a {@code LocalDateTime} based on this date-time with the nanoseconds added, not null
1337      * @throws DateTimeException if the result exceeds the supported date range
1338      */
1339     public LocalDateTime plusNanos(long nanos) {
1340         return plusWithOverflow(date, 0, 0, 0, nanos, 1);
1341     }
1342 
1343     //-----------------------------------------------------------------------
1344     /**
1345      * Returns a copy of this date-time with the specified amount subtracted.
1346      * <p>
1347      * This returns a {@code LocalDateTime}, based on this one, with the specified amount subtracted.
1348      * The amount is typically {@link Period} or {@link Duration} but may be
1349      * any other type implementing the {@link TemporalAmount} interface.
1350      * <p>
1351      * The calculation is delegated to the amount object by calling
1352      * {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
1353      * to implement the subtraction in any way it wishes, however it typically
1354      * calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
1355      * of the amount implementation to determine if it can be successfully subtracted.
1356      * <p>
1357      * This instance is immutable and unaffected by this method call.
1358      *
1359      * @param amountToSubtract  the amount to subtract, not null
1360      * @return a {@code LocalDateTime} based on this date-time with the subtraction made, not null
1361      * @throws DateTimeException if the subtraction cannot be made
1362      * @throws ArithmeticException if numeric overflow occurs
1363      */
1364     @Override
1365     public LocalDateTime minus(TemporalAmount amountToSubtract) {
1366         if (amountToSubtract instanceof Period) {
1367             Period periodToSubtract = (Period) amountToSubtract;
1368             return with(date.minus(periodToSubtract), time);
1369         }
1370         Objects.requireNonNull(amountToSubtract, "amountToSubtract");
1371         return (LocalDateTime) amountToSubtract.subtractFrom(this);
1372     }
1373 
1374     /**
1375      * Returns a copy of this date-time with the specified amount subtracted.
1376      * <p>
1377      * This returns a {@code LocalDateTime}, based on this one, with the amount
1378      * in terms of the unit subtracted. If it is not possible to subtract the amount,
1379      * because the unit is not supported or for some other reason, an exception is thrown.
1380      * <p>
1381      * This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
1382      * See that method for a full description of how addition, and thus subtraction, works.
1383      * <p>
1384      * This instance is immutable and unaffected by this method call.
1385      *
1386      * @param amountToSubtract  the amount of the unit to subtract from the result, may be negative
1387      * @param unit  the unit of the amount to subtract, not null
1388      * @return a {@code LocalDateTime} based on this date-time with the specified amount subtracted, not null
1389      * @throws DateTimeException if the subtraction cannot be made
1390      * @throws UnsupportedTemporalTypeException if the unit is not supported
1391      * @throws ArithmeticException if numeric overflow occurs
1392      */
1393     @Override
1394     public LocalDateTime minus(long amountToSubtract, TemporalUnit unit) {
1395         return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
1396     }
1397 
1398     //-----------------------------------------------------------------------
1399     /**
1400      * Returns a copy of this {@code LocalDateTime} with the specified number of years subtracted.
1401      * <p>
1402      * This method subtracts the specified amount from the years field in three steps:
1403      * <ol>
1404      * <li>Subtract the input years from the year field</li>
1405      * <li>Check if the resulting date would be invalid</li>
1406      * <li>Adjust the day-of-month to the last valid day if necessary</li>
1407      * </ol>
1408      * <p>
1409      * For example, 2008-02-29 (leap year) minus one year would result in the
1410      * invalid date 2009-02-29 (standard year). Instead of returning an invalid
1411      * result, the last valid day of the month, 2009-02-28, is selected instead.
1412      * <p>
1413      * This instance is immutable and unaffected by this method call.
1414      *
1415      * @param years  the years to subtract, may be negative
1416      * @return a {@code LocalDateTime} based on this date-time with the years subtracted, not null
1417      * @throws DateTimeException if the result exceeds the supported date range
1418      */
1419     public LocalDateTime minusYears(long years) {
1420         return (years == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-years));
1421     }
1422 
1423     /**
1424      * Returns a copy of this {@code LocalDateTime} with the specified number of months subtracted.
1425      * <p>
1426      * This method subtracts the specified amount from the months field in three steps:
1427      * <ol>
1428      * <li>Subtract the input months from the month-of-year field</li>
1429      * <li>Check if the resulting date would be invalid</li>
1430      * <li>Adjust the day-of-month to the last valid day if necessary</li>
1431      * </ol>
1432      * <p>
1433      * For example, 2007-03-31 minus one month would result in the invalid date
1434      * 2007-04-31. Instead of returning an invalid result, the last valid day
1435      * of the month, 2007-04-30, is selected instead.
1436      * <p>
1437      * This instance is immutable and unaffected by this method call.
1438      *
1439      * @param months  the months to subtract, may be negative
1440      * @return a {@code LocalDateTime} based on this date-time with the months subtracted, not null
1441      * @throws DateTimeException if the result exceeds the supported date range
1442      */
1443     public LocalDateTime minusMonths(long months) {
1444         return (months == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-months));
1445     }
1446 
1447     /**
1448      * Returns a copy of this {@code LocalDateTime} with the specified number of weeks subtracted.
1449      * <p>
1450      * This method subtracts the specified amount in weeks from the days field decrementing
1451      * the month and year fields as necessary to ensure the result remains valid.
1452      * The result is only invalid if the maximum/minimum year is exceeded.
1453      * <p>
1454      * For example, 2009-01-07 minus one week would result in 2008-12-31.
1455      * <p>
1456      * This instance is immutable and unaffected by this method call.
1457      *
1458      * @param weeks  the weeks to subtract, may be negative
1459      * @return a {@code LocalDateTime} based on this date-time with the weeks subtracted, not null
1460      * @throws DateTimeException if the result exceeds the supported date range
1461      */
1462     public LocalDateTime minusWeeks(long weeks) {
1463         return (weeks == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeks));
1464     }
1465 
1466     /**
1467      * Returns a copy of this {@code LocalDateTime} with the specified number of days subtracted.
1468      * <p>
1469      * This method subtracts the specified amount from the days field decrementing the
1470      * month and year fields as necessary to ensure the result remains valid.
1471      * The result is only invalid if the maximum/minimum year is exceeded.
1472      * <p>
1473      * For example, 2009-01-01 minus one day would result in 2008-12-31.
1474      * <p>
1475      * This instance is immutable and unaffected by this method call.
1476      *
1477      * @param days  the days to subtract, may be negative
1478      * @return a {@code LocalDateTime} based on this date-time with the days subtracted, not null
1479      * @throws DateTimeException if the result exceeds the supported date range
1480      */
1481     public LocalDateTime minusDays(long days) {
1482         return (days == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-days));
1483     }
1484 
1485     //-----------------------------------------------------------------------
1486     /**
1487      * Returns a copy of this {@code LocalDateTime} with the specified number of hours subtracted.
1488      * <p>
1489      * This instance is immutable and unaffected by this method call.
1490      *
1491      * @param hours  the hours to subtract, may be negative
1492      * @return a {@code LocalDateTime} based on this date-time with the hours subtracted, not null
1493      * @throws DateTimeException if the result exceeds the supported date range
1494      */
1495     public LocalDateTime minusHours(long hours) {
1496         return plusWithOverflow(date, hours, 0, 0, 0, -1);
1497    }
1498 
1499     /**
1500      * Returns a copy of this {@code LocalDateTime} with the specified number of minutes subtracted.
1501      * <p>
1502      * This instance is immutable and unaffected by this method call.
1503      *
1504      * @param minutes  the minutes to subtract, may be negative
1505      * @return a {@code LocalDateTime} based on this date-time with the minutes subtracted, not null
1506      * @throws DateTimeException if the result exceeds the supported date range
1507      */
1508     public LocalDateTime minusMinutes(long minutes) {
1509         return plusWithOverflow(date, 0, minutes, 0, 0, -1);
1510     }
1511 
1512     /**
1513      * Returns a copy of this {@code LocalDateTime} with the specified number of seconds subtracted.
1514      * <p>
1515      * This instance is immutable and unaffected by this method call.
1516      *
1517      * @param seconds  the seconds to subtract, may be negative
1518      * @return a {@code LocalDateTime} based on this date-time with the seconds subtracted, not null
1519      * @throws DateTimeException if the result exceeds the supported date range
1520      */
1521     public LocalDateTime minusSeconds(long seconds) {
1522         return plusWithOverflow(date, 0, 0, seconds, 0, -1);
1523     }
1524 
1525     /**
1526      * Returns a copy of this {@code LocalDateTime} with the specified number of nanoseconds subtracted.
1527      * <p>
1528      * This instance is immutable and unaffected by this method call.
1529      *
1530      * @param nanos  the nanos to subtract, may be negative
1531      * @return a {@code LocalDateTime} based on this date-time with the nanoseconds subtracted, not null
1532      * @throws DateTimeException if the result exceeds the supported date range
1533      */
1534     public LocalDateTime minusNanos(long nanos) {
1535         return plusWithOverflow(date, 0, 0, 0, nanos, -1);
1536     }
1537 
1538     //-----------------------------------------------------------------------
1539     /**
1540      * Returns a copy of this {@code LocalDateTime} with the specified period added.
1541      * <p>
1542      * This instance is immutable and unaffected by this method call.
1543      *
1544      * @param newDate  the new date to base the calculation on, not null
1545      * @param hours  the hours to add, may be negative
1546      * @param minutes the minutes to add, may be negative
1547      * @param seconds the seconds to add, may be negative
1548      * @param nanos the nanos to add, may be negative
1549      * @param sign  the sign to determine add or subtract
1550      * @return the combined result, not null
1551      */
1552     private LocalDateTime plusWithOverflow(LocalDate newDate, long hours, long minutes, long seconds, long nanos, int sign) {
1553         // 9223372036854775808 long, 2147483648 int
1554         if ((hours | minutes | seconds | nanos) == 0) {
1555             return with(newDate, time);
1556         }
1557         long totDays = nanos / NANOS_PER_DAY +             //   max/24*60*60*1B
1558                 seconds / SECONDS_PER_DAY +                //   max/24*60*60
1559                 minutes / MINUTES_PER_DAY +                //   max/24*60
1560                 hours / HOURS_PER_DAY;                     //   max/24
1561         totDays *= sign;                                   // total max*0.4237...
1562         long totNanos = nanos % NANOS_PER_DAY +                    //   max  86400000000000
1563                 (seconds % SECONDS_PER_DAY) * NANOS_PER_SECOND +   //   max  86400000000000
1564                 (minutes % MINUTES_PER_DAY) * NANOS_PER_MINUTE +   //   max  86400000000000
1565                 (hours % HOURS_PER_DAY) * NANOS_PER_HOUR;          //   max  86400000000000
1566         long curNoD = time.toNanoOfDay();                       //   max  86400000000000
1567         totNanos = totNanos * sign + curNoD;                    // total 432000000000000
1568         totDays += Math.floorDiv(totNanos, NANOS_PER_DAY);
1569         long newNoD = Math.floorMod(totNanos, NANOS_PER_DAY);
1570         LocalTime newTime = (newNoD == curNoD ? time : LocalTime.ofNanoOfDay(newNoD));
1571         return with(newDate.plusDays(totDays), newTime);
1572     }
1573 
1574     //-----------------------------------------------------------------------
1575     /**
1576      * Queries this date-time using the specified query.
1577      * <p>
1578      * This queries this date-time using the specified query strategy object.
1579      * The {@code TemporalQuery} object defines the logic to be used to
1580      * obtain the result. Read the documentation of the query to understand
1581      * what the result of this method will be.
1582      * <p>
1583      * The result of this method is obtained by invoking the
1584      * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
1585      * specified query passing {@code this} as the argument.
1586      *
1587      * @param <R> the type of the result
1588      * @param query  the query to invoke, not null
1589      * @return the query result, null may be returned (defined by the query)
1590      * @throws DateTimeException if unable to query (defined by the query)
1591      * @throws ArithmeticException if numeric overflow occurs (defined by the query)
1592      */
1593     @SuppressWarnings("unchecked")
1594     @Override  // override for Javadoc
1595     public <R> R query(TemporalQuery<R> query) {
1596         if (query == TemporalQueries.localDate()) {
1597             return (R) date;
1598         }
1599         return ChronoLocalDateTime.super.query(query);
1600     }
1601 
1602     /**
1603      * Adjusts the specified temporal object to have the same date and time as this object.
1604      * <p>
1605      * This returns a temporal object of the same observable type as the input
1606      * with the date and time changed to be the same as this.
1607      * <p>
1608      * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
1609      * twice, passing {@link ChronoField#EPOCH_DAY} and
1610      * {@link ChronoField#NANO_OF_DAY} as the fields.
1611      * <p>
1612      * In most cases, it is clearer to reverse the calling pattern by using
1613      * {@link Temporal#with(TemporalAdjuster)}:
1614      * <pre>
1615      *   // these two lines are equivalent, but the second approach is recommended
1616      *   temporal = thisLocalDateTime.adjustInto(temporal);
1617      *   temporal = temporal.with(thisLocalDateTime);
1618      * </pre>
1619      * <p>
1620      * This instance is immutable and unaffected by this method call.
1621      *
1622      * @param temporal  the target object to be adjusted, not null
1623      * @return the adjusted object, not null
1624      * @throws DateTimeException if unable to make the adjustment
1625      * @throws ArithmeticException if numeric overflow occurs
1626      */
1627     @Override  // override for Javadoc
1628     public Temporal adjustInto(Temporal temporal) {
1629         return ChronoLocalDateTime.super.adjustInto(temporal);
1630     }
1631 
1632     /**
1633      * Calculates the amount of time until another date-time in terms of the specified unit.
1634      * <p>
1635      * This calculates the amount of time between two {@code LocalDateTime}
1636      * objects in terms of a single {@code TemporalUnit}.
1637      * The start and end points are {@code this} and the specified date-time.
1638      * The result will be negative if the end is before the start.
1639      * The {@code Temporal} passed to this method is converted to a
1640      * {@code LocalDateTime} using {@link #from(TemporalAccessor)}.
1641      * For example, the amount in days between two date-times can be calculated
1642      * using {@code startDateTime.until(endDateTime, DAYS)}.
1643      * <p>
1644      * The calculation returns a whole number, representing the number of
1645      * complete units between the two date-times.
1646      * For example, the amount in months between 2012-06-15T00:00 and 2012-08-14T23:59
1647      * will only be one month as it is one minute short of two months.
1648      * <p>
1649      * There are two equivalent ways of using this method.
1650      * The first is to invoke this method.
1651      * The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
1652      * <pre>
1653      *   // these two lines are equivalent
1654      *   amount = start.until(end, MONTHS);
1655      *   amount = MONTHS.between(start, end);
1656      * </pre>
1657      * The choice should be made based on which makes the code more readable.
1658      * <p>
1659      * The calculation is implemented in this method for {@link ChronoUnit}.
1660      * The units {@code NANOS}, {@code MICROS}, {@code MILLIS}, {@code SECONDS},
1661      * {@code MINUTES}, {@code HOURS} and {@code HALF_DAYS}, {@code DAYS},
1662      * {@code WEEKS}, {@code MONTHS}, {@code YEARS}, {@code DECADES},
1663      * {@code CENTURIES}, {@code MILLENNIA} and {@code ERAS} are supported.
1664      * Other {@code ChronoUnit} values will throw an exception.
1665      * <p>
1666      * If the unit is not a {@code ChronoUnit}, then the result of this method
1667      * is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
1668      * passing {@code this} as the first argument and the converted input temporal
1669      * as the second argument.
1670      * <p>
1671      * This instance is immutable and unaffected by this method call.
1672      *
1673      * @param endExclusive  the end date, exclusive, which is converted to a {@code LocalDateTime}, not null
1674      * @param unit  the unit to measure the amount in, not null
1675      * @return the amount of time between this date-time and the end date-time
1676      * @throws DateTimeException if the amount cannot be calculated, or the end
1677      *  temporal cannot be converted to a {@code LocalDateTime}
1678      * @throws UnsupportedTemporalTypeException if the unit is not supported
1679      * @throws ArithmeticException if numeric overflow occurs
1680      */
1681     @Override
1682     public long until(Temporal endExclusive, TemporalUnit unit) {
1683         LocalDateTime end = LocalDateTime.from(endExclusive);
1684         if (unit instanceof ChronoUnit) {
1685             if (unit.isTimeBased()) {
1686                 long amount = date.daysUntil(end.date);
1687                 if (amount == 0) {
1688                     return time.until(end.time, unit);
1689                 }
1690                 long timePart = end.time.toNanoOfDay() - time.toNanoOfDay();
1691                 if (amount > 0) {
1692                     amount--;  // safe
1693                     timePart += NANOS_PER_DAY;  // safe
1694                 } else {
1695                     amount++;  // safe
1696                     timePart -= NANOS_PER_DAY;  // safe
1697                 }
1698                 switch ((ChronoUnit) unit) {
1699                     case NANOS:
1700                         amount = Math.multiplyExact(amount, NANOS_PER_DAY);
1701                         break;
1702                     case MICROS:
1703                         amount = Math.multiplyExact(amount, MICROS_PER_DAY);
1704                         timePart = timePart / 1000;
1705                         break;
1706                     case MILLIS:
1707                         amount = Math.multiplyExact(amount, MILLIS_PER_DAY);
1708                         timePart = timePart / 1_000_000;
1709                         break;
1710                     case SECONDS:
1711                         amount = Math.multiplyExact(amount, SECONDS_PER_DAY);
1712                         timePart = timePart / NANOS_PER_SECOND;
1713                         break;
1714                     case MINUTES:
1715                         amount = Math.multiplyExact(amount, MINUTES_PER_DAY);
1716                         timePart = timePart / NANOS_PER_MINUTE;
1717                         break;
1718                     case HOURS:
1719                         amount = Math.multiplyExact(amount, HOURS_PER_DAY);
1720                         timePart = timePart / NANOS_PER_HOUR;
1721                         break;
1722                     case HALF_DAYS:
1723                         amount = Math.multiplyExact(amount, 2);
1724                         timePart = timePart / (NANOS_PER_HOUR * 12);
1725                         break;
1726                 }
1727                 return Math.addExact(amount, timePart);
1728             }
1729             LocalDate endDate = end.date;
1730             if (endDate.isAfter(date) && end.time.isBefore(time)) {
1731                 endDate = endDate.minusDays(1);
1732             } else if (endDate.isBefore(date) && end.time.isAfter(time)) {
1733                 endDate = endDate.plusDays(1);
1734             }
1735             return date.until(endDate, unit);
1736         }
1737         return unit.between(this, end);
1738     }
1739 
1740     /**
1741      * Formats this date-time using the specified formatter.
1742      * <p>
1743      * This date-time will be passed to the formatter to produce a string.
1744      *
1745      * @param formatter  the formatter to use, not null
1746      * @return the formatted date-time string, not null
1747      * @throws DateTimeException if an error occurs during printing
1748      */
1749     @Override  // override for Javadoc and performance
1750     public String format(DateTimeFormatter formatter) {
1751         Objects.requireNonNull(formatter, "formatter");
1752         return formatter.format(this);
1753     }
1754 
1755     //-----------------------------------------------------------------------
1756     /**
1757      * Combines this date-time with an offset to create an {@code OffsetDateTime}.
1758      * <p>
1759      * This returns an {@code OffsetDateTime} formed from this date-time at the specified offset.
1760      * All possible combinations of date-time and offset are valid.
1761      *
1762      * @param offset  the offset to combine with, not null
1763      * @return the offset date-time formed from this date-time and the specified offset, not null
1764      */
1765     public OffsetDateTime atOffset(ZoneOffset offset) {
1766         return OffsetDateTime.of(this, offset);
1767     }
1768 
1769     /**
1770      * Combines this date-time with a time-zone to create a {@code ZonedDateTime}.
1771      * <p>
1772      * This returns a {@code ZonedDateTime} formed from this date-time at the
1773      * specified time-zone. The result will match this date-time as closely as possible.
1774      * Time-zone rules, such as daylight savings, mean that not every local date-time
1775      * is valid for the specified zone, thus the local date-time may be adjusted.
1776      * <p>
1777      * The local date-time is resolved to a single instant on the time-line.
1778      * This is achieved by finding a valid offset from UTC/Greenwich for the local
1779      * date-time as defined by the {@link ZoneRules rules} of the zone ID.
1780      *<p>
1781      * In most cases, there is only one valid offset for a local date-time.
1782      * In the case of an overlap, where clocks are set back, there are two valid offsets.
1783      * This method uses the earlier offset typically corresponding to "summer".
1784      * <p>
1785      * In the case of a gap, where clocks jump forward, there is no valid offset.
1786      * Instead, the local date-time is adjusted to be later by the length of the gap.
1787      * For a typical one hour daylight savings change, the local date-time will be
1788      * moved one hour later into the offset typically corresponding to "summer".
1789      * <p>
1790      * To obtain the later offset during an overlap, call
1791      * {@link ZonedDateTime#withLaterOffsetAtOverlap()} on the result of this method.
1792      * To throw an exception when there is a gap or overlap, use
1793      * {@link ZonedDateTime#ofStrict(LocalDateTime, ZoneOffset, ZoneId)}.
1794      *
1795      * @param zone  the time-zone to use, not null
1796      * @return the zoned date-time formed from this date-time, not null
1797      */
1798     @Override
1799     public ZonedDateTime atZone(ZoneId zone) {
1800         return ZonedDateTime.of(this, zone);
1801     }
1802 
1803     //-----------------------------------------------------------------------
1804     /**
1805      * Compares this date-time to another date-time.
1806      * <p>
1807      * The comparison is primarily based on the date-time, from earliest to latest.
1808      * It is "consistent with equals", as defined by {@link Comparable}.
1809      * <p>
1810      * If all the date-times being compared are instances of {@code LocalDateTime},
1811      * then the comparison will be entirely based on the date-time.
1812      * If some dates being compared are in different chronologies, then the
1813      * chronology is also considered, see {@link ChronoLocalDateTime#compareTo}.
1814      *
1815      * @param other  the other date-time to compare to, not null
1816      * @return the comparator value, negative if less, positive if greater
1817      */
1818     @Override  // override for Javadoc and performance
1819     public int compareTo(ChronoLocalDateTime<?> other) {
1820         if (other instanceof LocalDateTime) {
1821             return compareTo0((LocalDateTime) other);
1822         }
1823         return ChronoLocalDateTime.super.compareTo(other);
1824     }
1825 
1826     private int compareTo0(LocalDateTime other) {
1827         int cmp = date.compareTo0(other.toLocalDate());
1828         if (cmp == 0) {
1829             cmp = time.compareTo(other.toLocalTime());
1830         }
1831         return cmp;
1832     }
1833 
1834     /**
1835      * Checks if this date-time is after the specified date-time.
1836      * <p>
1837      * This checks to see if this date-time represents a point on the
1838      * local time-line after the other date-time.
1839      * <pre>
1840      *   LocalDate a = LocalDateTime.of(2012, 6, 30, 12, 00);
1841      *   LocalDate b = LocalDateTime.of(2012, 7, 1, 12, 00);
1842      *   a.isAfter(b) == false
1843      *   a.isAfter(a) == false
1844      *   b.isAfter(a) == true
1845      * </pre>
1846      * <p>
1847      * This method only considers the position of the two date-times on the local time-line.
1848      * It does not take into account the chronology, or calendar system.
1849      * This is different from the comparison in {@link #compareTo(ChronoLocalDateTime)},
1850      * but is the same approach as {@link ChronoLocalDateTime#timeLineOrder()}.
1851      *
1852      * @param other  the other date-time to compare to, not null
1853      * @return true if this date-time is after the specified date-time
1854      */
1855     @Override  // override for Javadoc and performance
1856     public boolean isAfter(ChronoLocalDateTime<?> other) {
1857         if (other instanceof LocalDateTime) {
1858             return compareTo0((LocalDateTime) other) > 0;
1859         }
1860         return ChronoLocalDateTime.super.isAfter(other);
1861     }
1862 
1863     /**
1864      * Checks if this date-time is before the specified date-time.
1865      * <p>
1866      * This checks to see if this date-time represents a point on the
1867      * local time-line before the other date-time.
1868      * <pre>
1869      *   LocalDate a = LocalDateTime.of(2012, 6, 30, 12, 00);
1870      *   LocalDate b = LocalDateTime.of(2012, 7, 1, 12, 00);
1871      *   a.isBefore(b) == true
1872      *   a.isBefore(a) == false
1873      *   b.isBefore(a) == false
1874      * </pre>
1875      * <p>
1876      * This method only considers the position of the two date-times on the local time-line.
1877      * It does not take into account the chronology, or calendar system.
1878      * This is different from the comparison in {@link #compareTo(ChronoLocalDateTime)},
1879      * but is the same approach as {@link ChronoLocalDateTime#timeLineOrder()}.
1880      *
1881      * @param other  the other date-time to compare to, not null
1882      * @return true if this date-time is before the specified date-time
1883      */
1884     @Override  // override for Javadoc and performance
1885     public boolean isBefore(ChronoLocalDateTime<?> other) {
1886         if (other instanceof LocalDateTime) {
1887             return compareTo0((LocalDateTime) other) < 0;
1888         }
1889         return ChronoLocalDateTime.super.isBefore(other);
1890     }
1891 
1892     /**
1893      * Checks if this date-time is equal to the specified date-time.
1894      * <p>
1895      * This checks to see if this date-time represents the same point on the
1896      * local time-line as the other date-time.
1897      * <pre>
1898      *   LocalDate a = LocalDateTime.of(2012, 6, 30, 12, 00);
1899      *   LocalDate b = LocalDateTime.of(2012, 7, 1, 12, 00);
1900      *   a.isEqual(b) == false
1901      *   a.isEqual(a) == true
1902      *   b.isEqual(a) == false
1903      * </pre>
1904      * <p>
1905      * This method only considers the position of the two date-times on the local time-line.
1906      * It does not take into account the chronology, or calendar system.
1907      * This is different from the comparison in {@link #compareTo(ChronoLocalDateTime)},
1908      * but is the same approach as {@link ChronoLocalDateTime#timeLineOrder()}.
1909      *
1910      * @param other  the other date-time to compare to, not null
1911      * @return true if this date-time is equal to the specified date-time
1912      */
1913     @Override  // override for Javadoc and performance
1914     public boolean isEqual(ChronoLocalDateTime<?> other) {
1915         if (other instanceof LocalDateTime) {
1916             return compareTo0((LocalDateTime) other) == 0;
1917         }
1918         return ChronoLocalDateTime.super.isEqual(other);
1919     }
1920 
1921     //-----------------------------------------------------------------------
1922     /**
1923      * Checks if this date-time is equal to another date-time.
1924      * <p>
1925      * Compares this {@code LocalDateTime} with another ensuring that the date-time is the same.
1926      * Only objects of type {@code LocalDateTime} are compared, other types return false.
1927      *
1928      * @param obj  the object to check, null returns false
1929      * @return true if this is equal to the other date-time
1930      */
1931     @Override
1932     public boolean equals(Object obj) {
1933         if (this == obj) {
1934             return true;
1935         }
1936         if (obj instanceof LocalDateTime) {
1937             LocalDateTime other = (LocalDateTime) obj;
1938             return date.equals(other.date) && time.equals(other.time);
1939         }
1940         return false;
1941     }
1942 
1943     /**
1944      * A hash code for this date-time.
1945      *
1946      * @return a suitable hash code
1947      */
1948     @Override
1949     public int hashCode() {
1950         return date.hashCode() ^ time.hashCode();
1951     }
1952 
1953     //-----------------------------------------------------------------------
1954     /**
1955      * Outputs this date-time as a {@code String}, such as {@code 2007-12-03T10:15:30}.
1956      * <p>
1957      * The output will be one of the following ISO-8601 formats:
1958      * <ul>
1959      * <li>{@code uuuu-MM-dd'T'HH:mm}</li>
1960      * <li>{@code uuuu-MM-dd'T'HH:mm:ss}</li>
1961      * <li>{@code uuuu-MM-dd'T'HH:mm:ss.SSS}</li>
1962      * <li>{@code uuuu-MM-dd'T'HH:mm:ss.SSSSSS}</li>
1963      * <li>{@code uuuu-MM-dd'T'HH:mm:ss.SSSSSSSSS}</li>
1964      * </ul>
1965      * The format used will be the shortest that outputs the full value of
1966      * the time where the omitted parts are implied to be zero.
1967      *
1968      * @return a string representation of this date-time, not null
1969      */
1970     @Override
1971     public String toString() {
1972         return date.toString() + 'T' + time.toString();
1973     }
1974 
1975     //-----------------------------------------------------------------------
1976     /**
1977      * Writes the object using a
1978      * <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
1979      * @serialData
1980      * <pre>
1981      *  out.writeByte(5);  // identifies a LocalDateTime
1982      *  // the <a href="../../serialized-form.html#java.time.LocalDate">date</a> excluding the one byte header
1983      *  // the <a href="../../serialized-form.html#java.time.LocalTime">time</a> excluding the one byte header
1984      * </pre>
1985      *
1986      * @return the instance of {@code Ser}, not null
1987      */
1988     private Object writeReplace() {
1989         return new Ser(Ser.LOCAL_DATE_TIME_TYPE, this);
1990     }
1991 
1992     /**
1993      * Defend against malicious streams.
1994      *
1995      * @param s the stream to read
1996      * @throws InvalidObjectException always
1997      */
1998     private void readObject(ObjectInputStream s) throws InvalidObjectException {
1999         throw new InvalidObjectException("Deserialization via serialization delegate");
2000     }
2001 
2002     void writeExternal(DataOutput out) throws IOException {
2003         date.writeExternal(out);
2004         time.writeExternal(out);
2005     }
2006 
2007     static LocalDateTime readExternal(DataInput in) throws IOException {
2008         LocalDate date = LocalDate.readExternal(in);
2009         LocalTime time = LocalTime.readExternal(in);
2010         return LocalDateTime.of(date, time);
2011     }
2012 
2013 }