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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.
	*/

	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* 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.DAY_OF_MONTH;
	import static java.time.temporal.ChronoField.ERA;
	import static java.time.temporal.ChronoField.HOUR_OF_DAY;
	import static java.time.temporal.ChronoField.MINUTE_OF_HOUR;
	import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
	import static java.time.temporal.ChronoField.PROLEPTIC_MONTH;
	import static java.time.temporal.ChronoField.SECOND_OF_MINUTE;
	import static java.time.temporal.ChronoField.YEAR;
	import static java.time.temporal.ChronoField.YEAR_OF_ERA;

	import java.io.InvalidObjectException;
	import java.io.ObjectInputStream;
	import java.io.Serializable;
	import java.time.Clock;
	import java.time.DateTimeException;
	import java.time.Instant;
	import java.time.LocalDate;
	import java.time.LocalDateTime;
	import java.time.Month;
	import java.time.Period;
	import java.time.Year;
	import java.time.ZonedDateTime;
	import java.time.ZoneId;
	import java.time.ZoneOffset;
	import java.time.format.ResolverStyle;
	import java.time.temporal.ChronoField;
	import java.time.temporal.TemporalAccessor;
	import java.time.temporal.TemporalField;
	import java.time.temporal.ValueRange;
	import java.util.List;
	import java.util.Locale;
	import java.util.Map;
	import java.util.Objects;

	/**
	* The ISO calendar system.
	* <p>
	* This chronology defines the rules of the ISO calendar system.
	* This calendar system is based on the ISO-8601 standard, which is the
	* <i>de facto</i> world calendar.
	* <p>
	* The fields are defined as follows:
	* <ul>
	* <li>era - There are two eras, 'Current Era' (CE) and 'Before Current Era' (BCE).
	* <li>year-of-era - The year-of-era is the same as the proleptic-year for the current CE era.
	* For the BCE era before the ISO epoch the year increases from 1 upwards as time goes backwards.
	* <li>proleptic-year - The proleptic year is the same as the year-of-era for the
	* current era. For the previous era, years have zero, then negative values.
	* <li>month-of-year - There are 12 months in an ISO year, numbered from 1 to 12.
	* <li>day-of-month - There are between 28 and 31 days in each of the ISO month, numbered from 1 to 31.
	* Months 4, 6, 9 and 11 have 30 days, Months 1, 3, 5, 7, 8, 10 and 12 have 31 days.
	* Month 2 has 28 days, or 29 in a leap year.
	* <li>day-of-year - There are 365 days in a standard ISO year and 366 in a leap year.
	* The days are numbered from 1 to 365 or 1 to 366.
	* <li>leap-year - Leap years occur every 4 years, except where the year is divisble by 100 and not divisble by 400.
	* </ul>
	*
	* @implSpec
	* This class is immutable and thread-safe.
	*
	* @since 1.8
	*/
	public final class IsoChronology extends AbstractChronology implements Serializable {

	/**
	* Singleton instance of the ISO chronology.
	*/
	public static final IsoChronology INSTANCE = new IsoChronology();

	/**
	* Serialization version.
	*/
	private static final long serialVersionUID = -1440403870442975015L;

	private static final long DAYS_0000_TO_1970 = (146097 * 5L) - (30L * 365L + 7L); // taken from LocalDate

	/**
	* Restricted constructor.
	*/
	private IsoChronology() {
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the ID of the chronology - 'ISO'.
	* <p>
	* The ID uniquely identifies the {@code Chronology}.
	* It can be used to lookup the {@code Chronology} using {@link Chronology#of(String)}.
	*
	* @return the chronology ID - 'ISO'
	* @see #getCalendarType()
	*/
	@Override
	public String getId() {
	return "ISO";
	}

	/**
	* Gets the calendar type of the underlying calendar system - 'iso8601'.
	* <p>
	* The calendar type is an identifier defined by the
	* <em>Unicode Locale Data Markup Language (LDML)</em> specification.
	* It can be used to lookup the {@code Chronology} using {@link Chronology#of(String)}.
	* It can also be used as part of a locale, accessible via
	* {@link Locale#getUnicodeLocaleType(String)} with the key 'ca'.
	*
	* @return the calendar system type - 'iso8601'
	* @see #getId()
	*/
	@Override
	public String getCalendarType() {
	return "iso8601";
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an ISO local date from the era, year-of-era, month-of-year
	* and day-of-month fields.
	*
	* @param era the ISO era, not null
	* @param yearOfEra the ISO year-of-era
	* @param month the ISO month-of-year
	* @param dayOfMonth the ISO day-of-month
	* @return the ISO local date, not null
	* @throws DateTimeException if unable to create the date
	* @throws ClassCastException if the type of {@code era} is not {@code IsoEra}
	*/
	@Override // override with covariant return type
	public LocalDate date(Era era, int yearOfEra, int month, int dayOfMonth) {
	return date(prolepticYear(era, yearOfEra), month, dayOfMonth);
	}

	/**
	* Obtains an ISO local date from the proleptic-year, month-of-year
	* and day-of-month fields.
	* <p>
	* This is equivalent to {@link LocalDate#of(int, int, int)}.
	*
	* @param prolepticYear the ISO proleptic-year
	* @param month the ISO month-of-year
	* @param dayOfMonth the ISO day-of-month
	* @return the ISO local date, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate date(int prolepticYear, int month, int dayOfMonth) {
	return LocalDate.of(prolepticYear, month, dayOfMonth);
	}

	/**
	* Obtains an ISO local date from the era, year-of-era and day-of-year fields.
	*
	* @param era the ISO era, not null
	* @param yearOfEra the ISO year-of-era
	* @param dayOfYear the ISO day-of-year
	* @return the ISO local date, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate dateYearDay(Era era, int yearOfEra, int dayOfYear) {
	return dateYearDay(prolepticYear(era, yearOfEra), dayOfYear);
	}

	/**
	* Obtains an ISO local date from the proleptic-year and day-of-year fields.
	* <p>
	* This is equivalent to {@link LocalDate#ofYearDay(int, int)}.
	*
	* @param prolepticYear the ISO proleptic-year
	* @param dayOfYear the ISO day-of-year
	* @return the ISO local date, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate dateYearDay(int prolepticYear, int dayOfYear) {
	return LocalDate.ofYearDay(prolepticYear, dayOfYear);
	}

	/**
	* Obtains an ISO local date from the epoch-day.
	* <p>
	* This is equivalent to {@link LocalDate#ofEpochDay(long)}.
	*
	* @param epochDay the epoch day
	* @return the ISO local date, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate dateEpochDay(long epochDay) {
	return LocalDate.ofEpochDay(epochDay);
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an ISO local date from another date-time object.
	* <p>
	* This is equivalent to {@link LocalDate#from(TemporalAccessor)}.
	*
	* @param temporal the date-time object to convert, not null
	* @return the ISO local date, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate date(TemporalAccessor temporal) {
	return LocalDate.from(temporal);
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the number of seconds from the epoch of 1970-01-01T00:00:00Z.
	* <p>
	* The number of seconds is calculated using the year,
	* month, day-of-month, hour, minute, second, and zoneOffset.
	*
	* @param prolepticYear the year, from MIN_YEAR to MAX_YEAR
	* @param month the month-of-year, from 1 to 12
	* @param dayOfMonth the day-of-month, from 1 to 31
	* @param hour the hour-of-day, from 0 to 23
	* @param minute the minute-of-hour, from 0 to 59
	* @param second the second-of-minute, from 0 to 59
	* @param zoneOffset the zone offset, not null
	* @return the number of seconds relative to 1970-01-01T00:00:00Z, may be negative
	* @throws DateTimeException if the value of any argument is out of range,
	* or if the day-of-month is invalid for the month-of-year
	* @since 9
	*/
	@Override
	public long epochSecond(int prolepticYear, int month, int dayOfMonth,
	int hour, int minute, int second, ZoneOffset zoneOffset) {
	YEAR.checkValidValue(prolepticYear);
	MONTH_OF_YEAR.checkValidValue(month);
	DAY_OF_MONTH.checkValidValue(dayOfMonth);
	HOUR_OF_DAY.checkValidValue(hour);
	MINUTE_OF_HOUR.checkValidValue(minute);
	SECOND_OF_MINUTE.checkValidValue(second);
	Objects.requireNonNull(zoneOffset, "zoneOffset");
	if (dayOfMonth > 28) {
	int dom = numberOfDaysOfMonth(prolepticYear, month);
	if (dayOfMonth > dom) {
	if (dayOfMonth == 29) {
	throw new DateTimeException("Invalid date 'February 29' as '" + prolepticYear + "' is not a leap year");
	} else {
	throw new DateTimeException("Invalid date '" + Month.of(month).name() + " " + dayOfMonth + "'");
	}
	}
	}

	long totalDays = 0;
	int timeinSec = 0;
	totalDays += 365L * prolepticYear;
	if (prolepticYear >= 0) {
	totalDays += (prolepticYear + 3L) / 4 - (prolepticYear + 99L) / 100 + (prolepticYear + 399L) / 400;
	} else {
	totalDays -= prolepticYear / -4 - prolepticYear / -100 + prolepticYear / -400;
	}
	totalDays += (367 * month - 362) / 12;
	totalDays += dayOfMonth - 1;
	if (month > 2) {
	totalDays--;
	if (IsoChronology.INSTANCE.isLeapYear(prolepticYear) == false) {
	totalDays--;
	}
	}
	totalDays -= DAYS_0000_TO_1970;
	timeinSec = (hour * 60 + minute ) * 60 + second;
	return Math.addExact(Math.multiplyExact(totalDays, 86400L), timeinSec - zoneOffset.getTotalSeconds());
	}

	/**
	* Gets the number of days for the given month in the given year.
	*
	* @param year the year to represent, from MIN_YEAR to MAX_YEAR
	* @param month the month-of-year to represent, from 1 to 12
	* @return the number of days for the given month in the given year
	*/
	private int numberOfDaysOfMonth(int year, int month) {
	int dom;
	switch (month) {
	case 2:
	dom = (IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
	break;
	case 4:
	case 6:
	case 9:
	case 11:
	dom = 30;
	break;
	default:
	dom = 31;
	break;
	}
	return dom;
	}


	/**
	* Obtains an ISO local date-time from another date-time object.
	* <p>
	* This is equivalent to {@link LocalDateTime#from(TemporalAccessor)}.
	*
	* @param temporal the date-time object to convert, not null
	* @return the ISO local date-time, not null
	* @throws DateTimeException if unable to create the date-time
	*/
	@Override // override with covariant return type
	public LocalDateTime localDateTime(TemporalAccessor temporal) {
	return LocalDateTime.from(temporal);
	}

	/**
	* Obtains an ISO zoned date-time from another date-time object.
	* <p>
	* This is equivalent to {@link ZonedDateTime#from(TemporalAccessor)}.
	*
	* @param temporal the date-time object to convert, not null
	* @return the ISO zoned date-time, not null
	* @throws DateTimeException if unable to create the date-time
	*/
	@Override // override with covariant return type
	public ZonedDateTime zonedDateTime(TemporalAccessor temporal) {
	return ZonedDateTime.from(temporal);
	}

	/**
	* Obtains an ISO zoned date-time in this chronology from an {@code Instant}.
	* <p>
	* This is equivalent to {@link ZonedDateTime#ofInstant(Instant, ZoneId)}.
	*
	* @param instant the instant to create the date-time from, not null
	* @param zone the time-zone, not null
	* @return the zoned date-time, not null
	* @throws DateTimeException if the result exceeds the supported range
	*/
	@Override
	public ZonedDateTime zonedDateTime(Instant instant, ZoneId zone) {
	return ZonedDateTime.ofInstant(instant, zone);
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains the current ISO local date 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 ISO local date using the system clock and default time-zone, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate dateNow() {
	return dateNow(Clock.systemDefaultZone());
	}

	/**
	* Obtains the current ISO local date 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.
	*
	* @return the current ISO local date using the system clock, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate dateNow(ZoneId zone) {
	return dateNow(Clock.system(zone));
	}

	/**
	* Obtains the current ISO local date 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 {@link Clock dependency injection}.
	*
	* @param clock the clock to use, not null
	* @return the current ISO local date, not null
	* @throws DateTimeException if unable to create the date
	*/
	@Override // override with covariant return type
	public LocalDate dateNow(Clock clock) {
	Objects.requireNonNull(clock, "clock");
	return date(LocalDate.now(clock));
	}

	//-----------------------------------------------------------------------
	/**
	* Checks if the year is a leap year, according to the ISO proleptic
	* calendar system rules.
	* <p>
	* This method applies the current rules for leap years across the whole time-line.
	* In general, a year is a leap year if it is divisible by four without
	* remainder. However, years divisible by 100, are not leap years, with
	* the exception of years divisible by 400 which are.
	* <p>
	* For example, 1904 is a leap year it is divisible by 4.
	* 1900 was not a leap year as it is divisible by 100, however 2000 was a
	* leap year as it is divisible by 400.
	* <p>
	* The calculation is proleptic - applying the same rules into the far future and far past.
	* This is historically inaccurate, but is correct for the ISO-8601 standard.
	*
	* @param prolepticYear the ISO proleptic year to check
	* @return true if the year is leap, false otherwise
	*/
	@Override
	public boolean isLeapYear(long prolepticYear) {
	return ((prolepticYear & 3) == 0) && ((prolepticYear % 100) != 0 \|\| (prolepticYear % 400) == 0);
	}

	@Override
	public int prolepticYear(Era era, int yearOfEra) {
	if (era instanceof IsoEra == false) {
	throw new ClassCastException("Era must be IsoEra");
	}
	return (era == IsoEra.CE ? yearOfEra : 1 - yearOfEra);
	}

	@Override
	public IsoEra eraOf(int eraValue) {
	return IsoEra.of(eraValue);
	}

	@Override
	public List<Era> eras() {
	return List.of(IsoEra.values());
	}

	//-----------------------------------------------------------------------
	/**
	* Resolves parsed {@code ChronoField} values into a date during parsing.
	* <p>
	* Most {@code TemporalField} implementations are resolved using the
	* resolve method on the field. By contrast, the {@code ChronoField} class
	* defines fields that only have meaning relative to the chronology.
	* As such, {@code ChronoField} date fields are resolved here in the
	* context of a specific chronology.
	* <p>
	* {@code ChronoField} instances on the ISO calendar system are resolved
	* as follows.
	* <ul>
	* <li>{@code EPOCH_DAY} - If present, this is converted to a {@code LocalDate}
	* and all other date fields are then cross-checked against the date.
	* <li>{@code PROLEPTIC_MONTH} - If present, then it is split into the
	* {@code YEAR} and {@code MONTH_OF_YEAR}. If the mode is strict or smart
	* then the field is validated.
	* <li>{@code YEAR_OF_ERA} and {@code ERA} - If both are present, then they
	* are combined to form a {@code YEAR}. In lenient mode, the {@code YEAR_OF_ERA}
	* range is not validated, in smart and strict mode it is. The {@code ERA} is
	* validated for range in all three modes. If only the {@code YEAR_OF_ERA} is
	* present, and the mode is smart or lenient, then the current era (CE/AD)
	* is assumed. In strict mode, no era is assumed and the {@code YEAR_OF_ERA} is
	* left untouched. If only the {@code ERA} is present, then it is left untouched.
	* <li>{@code YEAR}, {@code MONTH_OF_YEAR} and {@code DAY_OF_MONTH} -
	* If all three are present, then they are combined to form a {@code LocalDate}.
	* In all three modes, the {@code YEAR} is validated. If the mode is smart or strict,
	* then the month and day are validated, with the day validated from 1 to 31.
	* If the mode is lenient, then the date is combined in a manner equivalent to
	* creating a date on the first of January in the requested year, then adding
	* the difference in months, then the difference in days.
	* If the mode is smart, and the day-of-month is greater than the maximum for
	* the year-month, then the day-of-month is adjusted to the last day-of-month.
	* If the mode is strict, then the three fields must form a valid date.
	* <li>{@code YEAR} and {@code DAY_OF_YEAR} -
	* If both are present, then they are combined to form a {@code LocalDate}.
	* In all three modes, the {@code YEAR} is validated.
	* If the mode is lenient, then the date is combined in a manner equivalent to
	* creating a date on the first of January in the requested year, then adding
	* the difference in days.
	* If the mode is smart or strict, then the two fields must form a valid date.
	* <li>{@code YEAR}, {@code MONTH_OF_YEAR}, {@code ALIGNED_WEEK_OF_MONTH} and
	* {@code ALIGNED_DAY_OF_WEEK_IN_MONTH} -
	* If all four are present, then they are combined to form a {@code LocalDate}.
	* In all three modes, the {@code YEAR} is validated.
	* If the mode is lenient, then the date is combined in a manner equivalent to
	* creating a date on the first of January in the requested year, then adding
	* the difference in months, then the difference in weeks, then in days.
	* If the mode is smart or strict, then the all four fields are validated to
	* their outer ranges. The date is then combined in a manner equivalent to
	* creating a date on the first day of the requested year and month, then adding
	* the amount in weeks and days to reach their values. If the mode is strict,
	* the date is additionally validated to check that the day and week adjustment
	* did not change the month.
	* <li>{@code YEAR}, {@code MONTH_OF_YEAR}, {@code ALIGNED_WEEK_OF_MONTH} and
	* {@code DAY_OF_WEEK} - If all four are present, then they are combined to
	* form a {@code LocalDate}. The approach is the same as described above for
	* years, months and weeks in {@code ALIGNED_DAY_OF_WEEK_IN_MONTH}.
	* The day-of-week is adjusted as the next or same matching day-of-week once
	* the years, months and weeks have been handled.
	* <li>{@code YEAR}, {@code ALIGNED_WEEK_OF_YEAR} and {@code ALIGNED_DAY_OF_WEEK_IN_YEAR} -
	* If all three are present, then they are combined to form a {@code LocalDate}.
	* In all three modes, the {@code YEAR} is validated.
	* If the mode is lenient, then the date is combined in a manner equivalent to
	* creating a date on the first of January in the requested year, then adding
	* the difference in weeks, then in days.
	* If the mode is smart or strict, then the all three fields are validated to
	* their outer ranges. The date is then combined in a manner equivalent to
	* creating a date on the first day of the requested year, then adding
	* the amount in weeks and days to reach their values. If the mode is strict,
	* the date is additionally validated to check that the day and week adjustment
	* did not change the year.
	* <li>{@code YEAR}, {@code ALIGNED_WEEK_OF_YEAR} and {@code DAY_OF_WEEK} -
	* If all three are present, then they are combined to form a {@code LocalDate}.
	* The approach is the same as described above for years and weeks in
	* {@code ALIGNED_DAY_OF_WEEK_IN_YEAR}. The day-of-week is adjusted as the
	* next or same matching day-of-week once the years and weeks have been handled.
	* </ul>
	*
	* @param fieldValues the map of fields to values, which can be updated, not null
	* @param resolverStyle the requested type of resolve, not null
	* @return the resolved date, null if insufficient information to create a date
	* @throws DateTimeException if the date cannot be resolved, typically
	* because of a conflict in the input data
	*/
	@Override // override for performance
	public LocalDate resolveDate(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
	return (LocalDate) super.resolveDate(fieldValues, resolverStyle);
	}

	@Override // override for better proleptic algorithm
	void resolveProlepticMonth(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
	Long pMonth = fieldValues.remove(PROLEPTIC_MONTH);
	if (pMonth != null) {
	if (resolverStyle != ResolverStyle.LENIENT) {
	PROLEPTIC_MONTH.checkValidValue(pMonth);
	}
	addFieldValue(fieldValues, MONTH_OF_YEAR, Math.floorMod(pMonth, 12) + 1);
	addFieldValue(fieldValues, YEAR, Math.floorDiv(pMonth, 12));
	}
	}

	@Override // override for enhanced behaviour
	LocalDate resolveYearOfEra(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
	Long yoeLong = fieldValues.remove(YEAR_OF_ERA);
	if (yoeLong != null) {
	if (resolverStyle != ResolverStyle.LENIENT) {
	YEAR_OF_ERA.checkValidValue(yoeLong);
	}
	Long era = fieldValues.remove(ERA);
	if (era == null) {
	Long year = fieldValues.get(YEAR);
	if (resolverStyle == ResolverStyle.STRICT) {
	// do not invent era if strict, but do cross-check with year
	if (year != null) {
	addFieldValue(fieldValues, YEAR, (year > 0 ? yoeLong: Math.subtractExact(1, yoeLong)));
	} else {
	// reinstate the field removed earlier, no cross-check issues
	fieldValues.put(YEAR_OF_ERA, yoeLong);
	}
	} else {
	// invent era
	addFieldValue(fieldValues, YEAR, (year == null \|\| year > 0 ? yoeLong: Math.subtractExact(1, yoeLong)));
	}
	} else if (era.longValue() == 1L) {
	addFieldValue(fieldValues, YEAR, yoeLong);
	} else if (era.longValue() == 0L) {
	addFieldValue(fieldValues, YEAR, Math.subtractExact(1, yoeLong));
	} else {
	throw new DateTimeException("Invalid value for era: " + era);
	}
	} else if (fieldValues.containsKey(ERA)) {
	ERA.checkValidValue(fieldValues.get(ERA)); // always validated
	}
	return null;
	}

	@Override // override for performance
	LocalDate resolveYMD(Map <TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
	int y = YEAR.checkValidIntValue(fieldValues.remove(YEAR));
	if (resolverStyle == ResolverStyle.LENIENT) {
	long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1);
	long days = Math.subtractExact(fieldValues.remove(DAY_OF_MONTH), 1);
	return LocalDate.of(y, 1, 1).plusMonths(months).plusDays(days);
	}
	int moy = MONTH_OF_YEAR.checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR));
	int dom = DAY_OF_MONTH.checkValidIntValue(fieldValues.remove(DAY_OF_MONTH));
	if (resolverStyle == ResolverStyle.SMART) { // previous valid
	if (moy == 4 \|\| moy == 6 \|\| moy == 9 \|\| moy == 11) {
	dom = Math.min(dom, 30);
	} else if (moy == 2) {
	dom = Math.min(dom, Month.FEBRUARY.length(Year.isLeap(y)));

	}
	}
	return LocalDate.of(y, moy, dom);
	}

	//-----------------------------------------------------------------------
	@Override
	public ValueRange range(ChronoField field) {
	return field.range();
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains a period for this chronology based on years, months and days.
	* <p>
	* This returns a period tied to the ISO chronology using the specified
	* years, months and days. See {@link Period} for further details.
	*
	* @param years the number of years, may be negative
	* @param months the number of years, may be negative
	* @param days the number of years, may be negative
	* @return the period in terms of this chronology, not null
	* @return the ISO period, not null
	*/
	@Override // override with covariant return type
	public Period period(int years, int months, int days) {
	return Period.of(years, months, days);
	}

	//-----------------------------------------------------------------------
	/**
	* Writes the Chronology using a
	* <a href="../../../serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>.
	* @serialData
	* <pre>
	* out.writeByte(1); // identifies a Chronology
	* out.writeUTF(getId());
	* </pre>
	*
	* @return the instance of {@code Ser}, not null
	*/
	@Override
	Object writeReplace() {
	return super.writeReplace();
	}

	/**
	* 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");
	}
	}

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