/* * 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. */ /* * 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. *

* This date operates using the {@linkplain JapaneseChronology Japanese Imperial calendar}. * This calendar system is primarily used in Japan. *

* 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. *

* 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. *

* For example, the Japanese year "Heisei 24" corresponds to ISO year "2012".
* Calling {@code japaneseDate.get(YEAR_OF_ERA)} will return 24.
* Calling {@code japaneseDate.get(YEAR)} will return 2012.
* Calling {@code japaneseDate.get(ERA)} will return 2, corresponding to * {@code JapaneseChronology.ERA_HEISEI}.
* * @implSpec * This class is immutable and thread-safe. * * @since 1.8 */ public final class JapaneseDate extends ChronoLocalDateImpl 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. *

* This will query the {@link Clock#systemDefaultZone() system clock} in the default * time-zone to obtain the current date. *

* 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. *

* 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. *

* 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. *

* 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. *

* 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. *

* 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: *

     *  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
     * 
* * @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. *

* 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. *

* 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. *

* This returns a {@code JapaneseDate} with the specified fields. * The day must be valid for the year, otherwise an exception will be thrown. *

* 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: *

     *  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
     * 
* * @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. *

* 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}. *

* The conversion typically uses the {@link ChronoField#EPOCH_DAY EPOCH_DAY} * field, which is standardized across calendar systems. *

* 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. *

* 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. *

* 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. *

* 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. *

* 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. *

* If the field is a {@link ChronoField} then the query is implemented here. * The supported fields are: *

* All other {@code ChronoField} instances will return false. *

* 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. *

* 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. *

* 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. *

* 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. *

* 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 atTime(LocalTime localTime) { return (ChronoLocalDateTime)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. *

* Compares this {@code JapaneseDate} with another ensuring that the date is the same. *

* 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 * dedicated serialized form. * @serialData *

     *  out.writeByte(4);                 // identifies a JapaneseDate
     *  out.writeInt(get(YEAR));
     *  out.writeByte(get(MONTH_OF_YEAR));
     *  out.writeByte(get(DAY_OF_MONTH));
     * 
* * @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); } }