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   * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
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  /*
   * Copyright (c) 2012, Stephen Colebourne & Michael Nascimento Santos
   *
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   *  * Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   *
   *  * Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   *
   *  * Neither the name of JSR-310 nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package java.time.chrono;
  
  import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH;
  import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR;
  import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_MONTH;
  import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_YEAR;
  import static java.time.temporal.ChronoField.DAY_OF_MONTH;
  import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
  import static java.time.temporal.ChronoField.YEAR;
  
  import java.io.DataInput;
  import java.io.DataOutput;
  import java.io.IOException;
  import java.io.InvalidObjectException;
  import java.io.ObjectInputStream;
  import java.io.Serializable;
  import java.time.Clock;
  import java.time.DateTimeException;
  import java.time.LocalDate;
  import java.time.LocalTime;
  import java.time.Period;
  import java.time.ZoneId;
  import java.time.temporal.ChronoField;
  import java.time.temporal.TemporalAccessor;
  import java.time.temporal.TemporalAdjuster;
  import java.time.temporal.TemporalAmount;
  import java.time.temporal.TemporalField;
  import java.time.temporal.TemporalQuery;
  import java.time.temporal.TemporalUnit;
  import java.time.temporal.UnsupportedTemporalTypeException;
  import java.time.temporal.ValueRange;
  import java.util.Calendar;
  import java.util.Objects;
  
  import sun.util.calendar.CalendarDate;
  import sun.util.calendar.LocalGregorianCalendar;
  
  // Android-changed: removed ValueBased paragraph.
  
  /**
   * A date in the Japanese Imperial calendar system.
   * <p>
   * This date operates using the {@linkplain JapaneseChronology Japanese Imperial calendar}.
   * This calendar system is primarily used in Japan.
   * <p>
   * The Japanese Imperial calendar system is the same as the ISO calendar system
   * apart from the era-based year numbering. The proleptic-year is defined to be
   * equal to the ISO proleptic-year.
   * <p>
   * Japan introduced the Gregorian calendar starting with Meiji 6.
   * Only Meiji and later eras are supported;
   * dates before Meiji 6, January 1 are not supported.
   * <p>
   * For example, the Japanese year "Heisei 24" corresponds to ISO year "2012".<br>
   * Calling {@code japaneseDate.get(YEAR_OF_ERA)} will return 24.<br>
   * Calling {@code japaneseDate.get(YEAR)} will return 2012.<br>
   * Calling {@code japaneseDate.get(ERA)} will return 2, corresponding to
   * {@code JapaneseChronology.ERA_HEISEI}.<br>
   *
   * @implSpec
   * This class is immutable and thread-safe.
   *
   * @since 1.8
   */
  public final class JapaneseDate
          extends ChronoLocalDateImpl<JapaneseDate>
          implements ChronoLocalDate, Serializable {
  
      /**
       * Serialization version.
       */
      private static final long serialVersionUID = -305327627230580483L;
  
      /**
       * The underlying ISO local date.
       */
      private final transient LocalDate isoDate;
      /**
       * The JapaneseEra of this date.
       */
      private transient JapaneseEra era;
      /**
       * The Japanese imperial calendar year of this date.
       */
      private transient int yearOfEra;
  
      /**
       * The first day supported by the JapaneseChronology is Meiji 6, January 1st.
       */
      static final LocalDate MEIJI_6_ISODATE = LocalDate.of(1873, 1, 1);
  
      //-----------------------------------------------------------------------
      /**
       * Obtains the current {@code JapaneseDate} from the system clock in the default time-zone.
       * <p>
       * This will query the {@link Clock#systemDefaultZone() system clock} in the default
       * time-zone to obtain the current date.
       * <p>
       * Using this method will prevent the ability to use an alternate clock for testing
       * because the clock is hard-coded.
       *
       * @return the current date using the system clock and default time-zone, not null
       */
      public static JapaneseDate now() {
          return now(Clock.systemDefaultZone());
      }
  
      /**
       * Obtains the current {@code JapaneseDate} from the system clock in the specified time-zone.
       * <p>
       * This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date.
       * Specifying the time-zone avoids dependence on the default time-zone.
       * <p>
       * Using this method will prevent the ability to use an alternate clock for testing
       * because the clock is hard-coded.
       *
       * @param zone  the zone ID to use, not null
       * @return the current date using the system clock, not null
       */
      public static JapaneseDate now(ZoneId zone) {
          return now(Clock.system(zone));
      }
  
      /**
       * Obtains the current {@code JapaneseDate} from the specified clock.
       * <p>
       * This will query the specified clock to obtain the current date - today.
       * Using this method allows the use of an alternate clock for testing.
       * The alternate clock may be introduced using {@linkplain Clock dependency injection}.
       *
       * @param clock  the clock to use, not null
       * @return the current date, not null
       * @throws DateTimeException if the current date cannot be obtained
       */
      public static JapaneseDate now(Clock clock) {
          return new JapaneseDate(LocalDate.now(clock));
      }
  
      /**
       * Obtains a {@code JapaneseDate} representing a date in the Japanese calendar
       * system from the era, year-of-era, month-of-year and day-of-month fields.
       * <p>
       * This returns a {@code JapaneseDate} with the specified fields.
       * The day must be valid for the year and month, otherwise an exception will be thrown.
       * <p>
       * The Japanese month and day-of-month are the same as those in the
       * ISO calendar system. They are not reset when the era changes.
       * For example:
       * <pre>
       *  6th Jan Showa 64 = ISO 1989-01-06
       *  7th Jan Showa 64 = ISO 1989-01-07
       *  8th Jan Heisei 1 = ISO 1989-01-08
       *  9th Jan Heisei 1 = ISO 1989-01-09
       * </pre>
       *
       * @param era  the Japanese era, not null
       * @param yearOfEra  the Japanese year-of-era
       * @param month  the Japanese month-of-year, from 1 to 12
       * @param dayOfMonth  the Japanese day-of-month, from 1 to 31
       * @return the date in Japanese calendar system, not null
       * @throws DateTimeException if the value of any field is out of range,
       *  or if the day-of-month is invalid for the month-year,
       *  or if the date is not a Japanese era
       */
      public static JapaneseDate of(JapaneseEra era, int yearOfEra, int month, int dayOfMonth) {
          Objects.requireNonNull(era, "era");
          LocalGregorianCalendar.Date jdate = JapaneseChronology.JCAL.newCalendarDate(null);
          jdate.setEra(era.getPrivateEra()).setDate(yearOfEra, month, dayOfMonth);
          if (!JapaneseChronology.JCAL.validate(jdate)) {
              throw new DateTimeException("year, month, and day not valid for Era");
          }
          LocalDate date = LocalDate.of(jdate.getNormalizedYear(), month, dayOfMonth);
          return new JapaneseDate(era, yearOfEra, date);
      }
  
      /**
       * Obtains a {@code JapaneseDate} representing a date in the Japanese calendar
       * system from the proleptic-year, month-of-year and day-of-month fields.
       * <p>
       * This returns a {@code JapaneseDate} with the specified fields.
       * The day must be valid for the year and month, otherwise an exception will be thrown.
       * <p>
       * The Japanese proleptic year, month and day-of-month are the same as those
       * in the ISO calendar system. They are not reset when the era changes.
       *
       * @param prolepticYear  the Japanese proleptic-year
       * @param month  the Japanese month-of-year, from 1 to 12
       * @param dayOfMonth  the Japanese day-of-month, from 1 to 31
       * @return the date in Japanese calendar system, not null
       * @throws DateTimeException if the value of any field is out of range,
       *  or if the day-of-month is invalid for the month-year
       */
      public static JapaneseDate of(int prolepticYear, int month, int dayOfMonth) {
          return new JapaneseDate(LocalDate.of(prolepticYear, month, dayOfMonth));
      }
  
      /**
       * Obtains a {@code JapaneseDate} representing a date in the Japanese calendar
       * system from the era, year-of-era and day-of-year fields.
       * <p>
       * This returns a {@code JapaneseDate} with the specified fields.
       * The day must be valid for the year, otherwise an exception will be thrown.
       * <p>
       * The day-of-year in this factory is expressed relative to the start of the year-of-era.
       * This definition changes the normal meaning of day-of-year only in those years
       * where the year-of-era is reset to one due to a change in the era.
       * For example:
       * <pre>
       *  6th Jan Showa 64 = day-of-year 6
       *  7th Jan Showa 64 = day-of-year 7
       *  8th Jan Heisei 1 = day-of-year 1
       *  9th Jan Heisei 1 = day-of-year 2
       * </pre>
       *
       * @param era  the Japanese era, not null
       * @param yearOfEra  the Japanese year-of-era
       * @param dayOfYear  the chronology day-of-year, from 1 to 366
       * @return the date in Japanese calendar system, not null
       * @throws DateTimeException if the value of any field is out of range,
       *  or if the day-of-year is invalid for the year
       */
      static JapaneseDate ofYearDay(JapaneseEra era, int yearOfEra, int dayOfYear) {
          Objects.requireNonNull(era, "era");
          CalendarDate firstDay = era.getPrivateEra().getSinceDate();
          LocalGregorianCalendar.Date jdate = JapaneseChronology.JCAL.newCalendarDate(null);
          jdate.setEra(era.getPrivateEra());
          if (yearOfEra == 1) {
              jdate.setDate(yearOfEra, firstDay.getMonth(), firstDay.getDayOfMonth() + dayOfYear - 1);
          } else {
              jdate.setDate(yearOfEra, 1, dayOfYear);
          }
          JapaneseChronology.JCAL.normalize(jdate);
          if (era.getPrivateEra() != jdate.getEra() || yearOfEra != jdate.getYear()) {
              throw new DateTimeException("Invalid parameters");
          }
          LocalDate localdate = LocalDate.of(jdate.getNormalizedYear(),
                                        jdate.getMonth(), jdate.getDayOfMonth());
          return new JapaneseDate(era, yearOfEra, localdate);
      }
  
      /**
       * Obtains a {@code JapaneseDate} from a temporal object.
       * <p>
       * This obtains a date in the Japanese calendar system based on the specified temporal.
       * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
       * which this factory converts to an instance of {@code JapaneseDate}.
       * <p>
       * The conversion typically uses the {@link ChronoField#EPOCH_DAY EPOCH_DAY}
       * field, which is standardized across calendar systems.
       * <p>
       * This method matches the signature of the functional interface {@link TemporalQuery}
       * allowing it to be used as a query via method reference, {@code JapaneseDate::from}.
       *
       * @param temporal  the temporal object to convert, not null
       * @return the date in Japanese calendar system, not null
       * @throws DateTimeException if unable to convert to a {@code JapaneseDate}
       */
      public static JapaneseDate from(TemporalAccessor temporal) {
          return JapaneseChronology.INSTANCE.date(temporal);
      }
  
      //-----------------------------------------------------------------------
      /**
       * Creates an instance from an ISO date.
       *
       * @param isoDate  the standard local date, validated not null
       */
      JapaneseDate(LocalDate isoDate) {
          if (isoDate.isBefore(MEIJI_6_ISODATE)) {
              throw new DateTimeException("JapaneseDate before Meiji 6 is not supported");
          }
          LocalGregorianCalendar.Date jdate = toPrivateJapaneseDate(isoDate);
          this.era = JapaneseEra.toJapaneseEra(jdate.getEra());
          this.yearOfEra = jdate.getYear();
          this.isoDate = isoDate;
      }
  
      /**
       * Constructs a {@code JapaneseDate}. This constructor does NOT validate the given parameters,
       * and {@code era} and {@code year} must agree with {@code isoDate}.
       *
       * @param era  the era, validated not null
       * @param year  the year-of-era, validated
       * @param isoDate  the standard local date, validated not null
       */
      JapaneseDate(JapaneseEra era, int year, LocalDate isoDate) {
          if (isoDate.isBefore(MEIJI_6_ISODATE)) {
              throw new DateTimeException("JapaneseDate before Meiji 6 is not supported");
          }
          this.era = era;
          this.yearOfEra = year;
          this.isoDate = isoDate;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Gets the chronology of this date, which is the Japanese calendar system.
       * <p>
       * The {@code Chronology} represents the calendar system in use.
       * The era and other fields in {@link ChronoField} are defined by the chronology.
       *
       * @return the Japanese chronology, not null
       */
      @Override
      public JapaneseChronology getChronology() {
          return JapaneseChronology.INSTANCE;
      }
  
      /**
       * Gets the era applicable at this date.
       * <p>
       * The Japanese calendar system has multiple eras defined by {@link JapaneseEra}.
       *
       * @return the era applicable at this date, not null
       */
      @Override
      public JapaneseEra getEra() {
          return era;
      }
  
      /**
       * Returns the length of the month represented by this date.
       * <p>
       * This returns the length of the month in days.
       * Month lengths match those of the ISO calendar system.
       *
       * @return the length of the month in days
       */
      @Override
      public int lengthOfMonth() {
          return isoDate.lengthOfMonth();
      }
  
      @Override
      public int lengthOfYear() {
          // Android-changed: use #createCalendar() to create calendar.
          Calendar jcal = JapaneseChronology.createCalendar();
          jcal.set(Calendar.ERA, era.getValue() + JapaneseEra.ERA_OFFSET);
          jcal.set(yearOfEra, isoDate.getMonthValue() - 1, isoDate.getDayOfMonth());
          return  jcal.getActualMaximum(Calendar.DAY_OF_YEAR);
      }
  
      //-----------------------------------------------------------------------
      /**
       * Checks if the specified field is supported.
       * <p>
       * This checks if this date can be queried for the specified field.
       * If false, then calling the {@link #range(TemporalField) range} and
       * {@link #get(TemporalField) get} methods will throw an exception.
       * <p>
       * If the field is a {@link ChronoField} then the query is implemented here.
       * The supported fields are:
       * <ul>
       * <li>{@code DAY_OF_WEEK}
       * <li>{@code DAY_OF_MONTH}
       * <li>{@code DAY_OF_YEAR}
       * <li>{@code EPOCH_DAY}
       * <li>{@code MONTH_OF_YEAR}
       * <li>{@code PROLEPTIC_MONTH}
       * <li>{@code YEAR_OF_ERA}
       * <li>{@code YEAR}
       * <li>{@code ERA}
       * </ul>
       * All other {@code ChronoField} instances will return false.
       * <p>
       * If the field is not a {@code ChronoField}, then the result of this method
       * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
       * passing {@code this} as the argument.
       * Whether the field is supported is determined by the field.
       *
       * @param field  the field to check, null returns false
       * @return true if the field is supported on this date, false if not
       */
      @Override
      public boolean isSupported(TemporalField field) {
          if (field == ALIGNED_DAY_OF_WEEK_IN_MONTH || field == ALIGNED_DAY_OF_WEEK_IN_YEAR ||
                  field == ALIGNED_WEEK_OF_MONTH || field == ALIGNED_WEEK_OF_YEAR) {
              return false;
          }
          // Android-changed: Apply upstream OpenJDK 9 compilation fix.
          // Applied OpenJDK 9 change from http://hg.openjdk.java.net/jdk9/dev/jdk/rev/2b7b09c81bf1
          // On OpenJDK 8, either version is supported and has the same behavior.
          // return ChronoLocalDate.super.isSupported(field);
          return super.isSupported(field);
      }
  
      @Override
      public ValueRange range(TemporalField field) {
          if (field instanceof ChronoField) {
              if (isSupported(field)) {
                  ChronoField f = (ChronoField) field;
                  switch (f) {
                      case DAY_OF_MONTH: return ValueRange.of(1, lengthOfMonth());
                      case DAY_OF_YEAR: return ValueRange.of(1, lengthOfYear());
                      case YEAR_OF_ERA: {
                          // Android-changed: use #createCalendar() to create calendar.
                          Calendar jcal = JapaneseChronology.createCalendar();
                          jcal.set(Calendar.ERA, era.getValue() + JapaneseEra.ERA_OFFSET);
                          jcal.set(yearOfEra, isoDate.getMonthValue() - 1, isoDate.getDayOfMonth());
                          return ValueRange.of(1, jcal.getActualMaximum(Calendar.YEAR));
                      }
                  }
                  return getChronology().range(f);
              }
              throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
          }
          return field.rangeRefinedBy(this);
      }
  
      @Override
      public long getLong(TemporalField field) {
          if (field instanceof ChronoField) {
              // same as ISO:
              // DAY_OF_WEEK, DAY_OF_MONTH, EPOCH_DAY, MONTH_OF_YEAR, PROLEPTIC_MONTH, YEAR
              //
              // calendar specific fields
              // DAY_OF_YEAR, YEAR_OF_ERA, ERA
              switch ((ChronoField) field) {
                  case ALIGNED_DAY_OF_WEEK_IN_MONTH:
                  case ALIGNED_DAY_OF_WEEK_IN_YEAR:
                  case ALIGNED_WEEK_OF_MONTH:
                  case ALIGNED_WEEK_OF_YEAR:
                      throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
                  case YEAR_OF_ERA:
                      return yearOfEra;
                  case ERA:
                      return era.getValue();
                  case DAY_OF_YEAR:
                      // Android-changed: use #createCalendar() to create calendar.
                      Calendar jcal = JapaneseChronology.createCalendar();
                      jcal.set(Calendar.ERA, era.getValue() + JapaneseEra.ERA_OFFSET);
                      jcal.set(yearOfEra, isoDate.getMonthValue() - 1, isoDate.getDayOfMonth());
                      return jcal.get(Calendar.DAY_OF_YEAR);
              }
              return isoDate.getLong(field);
          }
          return field.getFrom(this);
      }
  
      /**
       * Returns a {@code LocalGregorianCalendar.Date} converted from the given {@code isoDate}.
       *
       * @param isoDate  the local date, not null
       * @return a {@code LocalGregorianCalendar.Date}, not null
       */
      private static LocalGregorianCalendar.Date toPrivateJapaneseDate(LocalDate isoDate) {
          LocalGregorianCalendar.Date jdate = JapaneseChronology.JCAL.newCalendarDate(null);
          sun.util.calendar.Era sunEra = JapaneseEra.privateEraFrom(isoDate);
          int year = isoDate.getYear();
          if (sunEra != null) {
              year -= sunEra.getSinceDate().getYear() - 1;
          }
          jdate.setEra(sunEra).setYear(year).setMonth(isoDate.getMonthValue()).setDayOfMonth(isoDate.getDayOfMonth());
          JapaneseChronology.JCAL.normalize(jdate);
          return jdate;
      }
  
      //-----------------------------------------------------------------------
      @Override
      public JapaneseDate with(TemporalField field, long newValue) {
          if (field instanceof ChronoField) {
              ChronoField f = (ChronoField) field;
              if (getLong(f) == newValue) {  // getLong() validates for supported fields
                  return this;
              }
              switch (f) {
                  case YEAR_OF_ERA:
                  case YEAR:
                  case ERA: {
                      int nvalue = getChronology().range(f).checkValidIntValue(newValue, f);
                      switch (f) {
                          case YEAR_OF_ERA:
                              return this.withYear(nvalue);
                          case YEAR:
                              return with(isoDate.withYear(nvalue));
                          case ERA: {
                              return this.withYear(JapaneseEra.of(nvalue), yearOfEra);
                          }
                      }
                  }
              }
              // YEAR, PROLEPTIC_MONTH and others are same as ISO
              return with(isoDate.with(field, newValue));
          }
          return super.with(field, newValue);
      }
  
      /**
       * {@inheritDoc}
       * @throws DateTimeException {@inheritDoc}
       * @throws ArithmeticException {@inheritDoc}
       */
      @Override
      public  JapaneseDate with(TemporalAdjuster adjuster) {
          return super.with(adjuster);
      }
  
      /**
       * {@inheritDoc}
       * @throws DateTimeException {@inheritDoc}
       * @throws ArithmeticException {@inheritDoc}
       */
      @Override
      public JapaneseDate plus(TemporalAmount amount) {
          return super.plus(amount);
      }
  
      /**
       * {@inheritDoc}
       * @throws DateTimeException {@inheritDoc}
       * @throws ArithmeticException {@inheritDoc}
       */
      @Override
      public JapaneseDate minus(TemporalAmount amount) {
          return super.minus(amount);
      }
      //-----------------------------------------------------------------------
      /**
       * Returns a copy of this date with the year altered.
       * <p>
       * This method changes the year of the date.
       * If the month-day is invalid for the year, then the previous valid day
       * will be selected instead.
       * <p>
       * This instance is immutable and unaffected by this method call.
       *
       * @param era  the era to set in the result, not null
       * @param yearOfEra  the year-of-era to set in the returned date
       * @return a {@code JapaneseDate} based on this date with the requested year, never null
       * @throws DateTimeException if {@code year} is invalid
       */
      private JapaneseDate withYear(JapaneseEra era, int yearOfEra) {
          int year = JapaneseChronology.INSTANCE.prolepticYear(era, yearOfEra);
          return with(isoDate.withYear(year));
      }
  
      /**
       * Returns a copy of this date with the year-of-era altered.
       * <p>
       * This method changes the year-of-era of the date.
       * If the month-day is invalid for the year, then the previous valid day
       * will be selected instead.
       * <p>
       * This instance is immutable and unaffected by this method call.
       *
       * @param year  the year to set in the returned date
       * @return a {@code JapaneseDate} based on this date with the requested year-of-era, never null
       * @throws DateTimeException if {@code year} is invalid
       */
      private JapaneseDate withYear(int year) {
          return withYear(getEra(), year);
      }
  
      //-----------------------------------------------------------------------
      @Override
      JapaneseDate plusYears(long years) {
          return with(isoDate.plusYears(years));
      }
  
      @Override
      JapaneseDate plusMonths(long months) {
          return with(isoDate.plusMonths(months));
      }
  
      @Override
      JapaneseDate plusWeeks(long weeksToAdd) {
          return with(isoDate.plusWeeks(weeksToAdd));
      }
  
      @Override
      JapaneseDate plusDays(long days) {
          return with(isoDate.plusDays(days));
      }
  
      @Override
      public JapaneseDate plus(long amountToAdd, TemporalUnit unit) {
          return super.plus(amountToAdd, unit);
      }
  
      @Override
      public JapaneseDate minus(long amountToAdd, TemporalUnit unit) {
          return super.minus(amountToAdd, unit);
      }
  
      @Override
      JapaneseDate minusYears(long yearsToSubtract) {
          return super.minusYears(yearsToSubtract);
      }
  
      @Override
      JapaneseDate minusMonths(long monthsToSubtract) {
          return super.minusMonths(monthsToSubtract);
      }
  
      @Override
      JapaneseDate minusWeeks(long weeksToSubtract) {
          return super.minusWeeks(weeksToSubtract);
      }
  
      @Override
      JapaneseDate minusDays(long daysToSubtract) {
          return super.minusDays(daysToSubtract);
      }
  
      private JapaneseDate with(LocalDate newDate) {
          return (newDate.equals(isoDate) ? this : new JapaneseDate(newDate));
      }
  
      @Override        // for javadoc and covariant return type
      @SuppressWarnings("unchecked")
      public final ChronoLocalDateTime<JapaneseDate> atTime(LocalTime localTime) {
          return (ChronoLocalDateTime<JapaneseDate>)super.atTime(localTime);
      }
  
      @Override
      public ChronoPeriod until(ChronoLocalDate endDate) {
          Period period = isoDate.until(endDate);
          return getChronology().period(period.getYears(), period.getMonths(), period.getDays());
      }
  
      @Override  // override for performance
      public long toEpochDay() {
          return isoDate.toEpochDay();
      }
  
      //-------------------------------------------------------------------------
      /**
       * Compares this date to another date, including the chronology.
       * <p>
       * Compares this {@code JapaneseDate} with another ensuring that the date is the same.
       * <p>
       * Only objects of type {@code JapaneseDate} are compared, other types return false.
       * To compare the dates of two {@code TemporalAccessor} instances, including dates
       * in two different chronologies, use {@link ChronoField#EPOCH_DAY} as a comparator.
       *
       * @param obj  the object to check, null returns false
       * @return true if this is equal to the other date
       */
      @Override  // override for performance
      public boolean equals(Object obj) {
          if (this == obj) {
              return true;
          }
          if (obj instanceof JapaneseDate) {
              JapaneseDate otherDate = (JapaneseDate) obj;
              return this.isoDate.equals(otherDate.isoDate);
          }
          return false;
      }
  
      /**
       * A hash code for this date.
       *
       * @return a suitable hash code based only on the Chronology and the date
       */
      @Override  // override for performance
      public int hashCode() {
          return getChronology().getId().hashCode() ^ isoDate.hashCode();
      }
  
      //-----------------------------------------------------------------------
      /**
       * Defend against malicious streams.
       *
       * @param s the stream to read
       * @throws InvalidObjectException always
       */
      private void readObject(ObjectInputStream s) throws InvalidObjectException {
          throw new InvalidObjectException("Deserialization via serialization delegate");
      }
  
      /**
       * Writes the object using a
       * <a href="../../../serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>.
       * @serialData
       * <pre>
       *  out.writeByte(4);                 // identifies a JapaneseDate
       *  out.writeInt(get(YEAR));
       *  out.writeByte(get(MONTH_OF_YEAR));
       *  out.writeByte(get(DAY_OF_MONTH));
       * </pre>
       *
       * @return the instance of {@code Ser}, not null
       */
      private Object writeReplace() {
          return new Ser(Ser.JAPANESE_DATE_TYPE, this);
      }
  
      void writeExternal(DataOutput out) throws IOException {
          // JapaneseChronology is implicit in the JAPANESE_DATE_TYPE
          out.writeInt(get(YEAR));
          out.writeByte(get(MONTH_OF_YEAR));
          out.writeByte(get(DAY_OF_MONTH));
      }
  
      static JapaneseDate readExternal(DataInput in) throws IOException {
          int year = in.readInt();
          int month = in.readByte();
          int dayOfMonth = in.readByte();
          return JapaneseChronology.INSTANCE.date(year, month, dayOfMonth);
      }
  
  }
  