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	/*
	* Copyright (c) 2012, 2018, 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) 2011-2012, 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.temporal;

	import static java.time.DayOfWeek.THURSDAY;
	import static java.time.DayOfWeek.WEDNESDAY;
	import static java.time.temporal.ChronoField.DAY_OF_WEEK;
	import static java.time.temporal.ChronoField.DAY_OF_YEAR;
	import static java.time.temporal.ChronoField.EPOCH_DAY;
	import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
	import static java.time.temporal.ChronoField.YEAR;
	import static java.time.temporal.ChronoUnit.DAYS;
	import static java.time.temporal.ChronoUnit.FOREVER;
	import static java.time.temporal.ChronoUnit.MONTHS;
	import static java.time.temporal.ChronoUnit.WEEKS;
	import static java.time.temporal.ChronoUnit.YEARS;

	import java.time.DateTimeException;
	import java.time.Duration;
	import java.time.LocalDate;
	import java.time.chrono.ChronoLocalDate;
	import java.time.chrono.Chronology;
	import java.time.chrono.IsoChronology;
	import java.time.format.ResolverStyle;
	import java.util.Locale;
	import java.util.Map;
	import java.util.Objects;
	import java.util.ResourceBundle;

	import sun.util.locale.provider.LocaleProviderAdapter;
	import sun.util.locale.provider.LocaleResources;

	/**
	* Fields and units specific to the ISO-8601 calendar system,
	* including quarter-of-year and week-based-year.
	* <p>
	* This class defines fields and units that are specific to the ISO calendar system.
	*
	* <h3>Quarter of year</h3>
	* The ISO-8601 standard is based on the standard civic 12 month year.
	* This is commonly divided into four quarters, often abbreviated as Q1, Q2, Q3 and Q4.
	* <p>
	* January, February and March are in Q1.
	* April, May and June are in Q2.
	* July, August and September are in Q3.
	* October, November and December are in Q4.
	* <p>
	* The complete date is expressed using three fields:
	* <ul>
	* <li>{@link #DAY_OF_QUARTER DAY_OF_QUARTER} - the day within the quarter, from 1 to 90, 91 or 92
	* <li>{@link #QUARTER_OF_YEAR QUARTER_OF_YEAR} - the week within the week-based-year
	* <li>{@link ChronoField#YEAR YEAR} - the standard ISO year
	* </ul>
	*
	* <h3>Week based years</h3>
	* The ISO-8601 standard was originally intended as a data interchange format,
	* defining a string format for dates and times. However, it also defines an
	* alternate way of expressing the date, based on the concept of week-based-year.
	* <p>
	* The date is expressed using three fields:
	* <ul>
	* <li>{@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} - the standard field defining the
	* day-of-week from Monday (1) to Sunday (7)
	* <li>{@link #WEEK_OF_WEEK_BASED_YEAR} - the week within the week-based-year
	* <li>{@link #WEEK_BASED_YEAR WEEK_BASED_YEAR} - the week-based-year
	* </ul>
	* The week-based-year itself is defined relative to the standard ISO proleptic year.
	* It differs from the standard year in that it always starts on a Monday.
	* <p>
	* The first week of a week-based-year is the first Monday-based week of the standard
	* ISO year that has at least 4 days in the new year.
	* <ul>
	* <li>If January 1st is Monday then week 1 starts on January 1st
	* <li>If January 1st is Tuesday then week 1 starts on December 31st of the previous standard year
	* <li>If January 1st is Wednesday then week 1 starts on December 30th of the previous standard year
	* <li>If January 1st is Thursday then week 1 starts on December 29th of the previous standard year
	* <li>If January 1st is Friday then week 1 starts on January 4th
	* <li>If January 1st is Saturday then week 1 starts on January 3rd
	* <li>If January 1st is Sunday then week 1 starts on January 2nd
	* </ul>
	* There are 52 weeks in most week-based years, however on occasion there are 53 weeks.
	* <p>
	* For example:
	*
	* <table cellpadding="0" cellspacing="3" border="0" style="text-align: left; width: 50%;">
	* <caption>Examples of Week based Years</caption>
	* <tr><th>Date</th><th>Day-of-week</th><th>Field values</th></tr>
	* <tr><th>2008-12-28</th><td>Sunday</td><td>Week 52 of week-based-year 2008</td></tr>
	* <tr><th>2008-12-29</th><td>Monday</td><td>Week 1 of week-based-year 2009</td></tr>
	* <tr><th>2008-12-31</th><td>Wednesday</td><td>Week 1 of week-based-year 2009</td></tr>
	* <tr><th>2009-01-01</th><td>Thursday</td><td>Week 1 of week-based-year 2009</td></tr>
	* <tr><th>2009-01-04</th><td>Sunday</td><td>Week 1 of week-based-year 2009</td></tr>
	* <tr><th>2009-01-05</th><td>Monday</td><td>Week 2 of week-based-year 2009</td></tr>
	* </table>
	*
	* @implSpec
	* <p>
	* This class is immutable and thread-safe.
	*
	* @since 1.8
	*/
	public final class IsoFields {

	/**
	* The field that represents the day-of-quarter.
	* <p>
	* This field allows the day-of-quarter value to be queried and set.
	* The day-of-quarter has values from 1 to 90 in Q1 of a standard year, from 1 to 91
	* in Q1 of a leap year, from 1 to 91 in Q2 and from 1 to 92 in Q3 and Q4.
	* <p>
	* The day-of-quarter can only be calculated if the day-of-year, month-of-year and year
	* are available.
	* <p>
	* When setting this field, the value is allowed to be partially lenient, taking any
	* value from 1 to 92. If the quarter has less than 92 days, then day 92, and
	* potentially day 91, is in the following quarter.
	* <p>
	* In the resolving phase of parsing, a date can be created from a year,
	* quarter-of-year and day-of-quarter.
	* <p>
	* In {@linkplain ResolverStyle#STRICT strict mode}, all three fields are
	* validated against their range of valid values. The day-of-quarter field
	* is validated from 1 to 90, 91 or 92 depending on the year and quarter.
	* <p>
	* In {@linkplain ResolverStyle#SMART smart mode}, all three fields are
	* validated against their range of valid values. The day-of-quarter field is
	* validated between 1 and 92, ignoring the actual range based on the year and quarter.
	* If the day-of-quarter exceeds the actual range by one day, then the resulting date
	* is one day later. If the day-of-quarter exceeds the actual range by two days,
	* then the resulting date is two days later.
	* <p>
	* In {@linkplain ResolverStyle#LENIENT lenient mode}, only the year is validated
	* against the range of valid values. The resulting date is calculated equivalent to
	* the following three stage approach. First, create a date on the first of January
	* in the requested year. Then take the quarter-of-year, subtract one, and add the
	* amount in quarters to the date. Finally, take the day-of-quarter, subtract one,
	* and add the amount in days to the date.
	* <p>
	* This unit is an immutable and thread-safe singleton.
	*/
	public static final TemporalField DAY_OF_QUARTER = Field.DAY_OF_QUARTER;
	/**
	* The field that represents the quarter-of-year.
	* <p>
	* This field allows the quarter-of-year value to be queried and set.
	* The quarter-of-year has values from 1 to 4.
	* <p>
	* The quarter-of-year can only be calculated if the month-of-year is available.
	* <p>
	* In the resolving phase of parsing, a date can be created from a year,
	* quarter-of-year and day-of-quarter.
	* See {@link #DAY_OF_QUARTER} for details.
	* <p>
	* This unit is an immutable and thread-safe singleton.
	*/
	public static final TemporalField QUARTER_OF_YEAR = Field.QUARTER_OF_YEAR;
	/**
	* The field that represents the week-of-week-based-year.
	* <p>
	* This field allows the week of the week-based-year value to be queried and set.
	* The week-of-week-based-year has values from 1 to 52, or 53 if the
	* week-based-year has 53 weeks.
	* <p>
	* In the resolving phase of parsing, a date can be created from a
	* week-based-year, week-of-week-based-year and day-of-week.
	* <p>
	* In {@linkplain ResolverStyle#STRICT strict mode}, all three fields are
	* validated against their range of valid values. The week-of-week-based-year
	* field is validated from 1 to 52 or 53 depending on the week-based-year.
	* <p>
	* In {@linkplain ResolverStyle#SMART smart mode}, all three fields are
	* validated against their range of valid values. The week-of-week-based-year
	* field is validated between 1 and 53, ignoring the week-based-year.
	* If the week-of-week-based-year is 53, but the week-based-year only has
	* 52 weeks, then the resulting date is in week 1 of the following week-based-year.
	* <p>
	* In {@linkplain ResolverStyle#LENIENT lenient mode}, only the week-based-year
	* is validated against the range of valid values. If the day-of-week is outside
	* the range 1 to 7, then the resulting date is adjusted by a suitable number of
	* weeks to reduce the day-of-week to the range 1 to 7. If the week-of-week-based-year
	* value is outside the range 1 to 52, then any excess weeks are added or subtracted
	* from the resulting date.
	* <p>
	* This unit is an immutable and thread-safe singleton.
	*/
	public static final TemporalField WEEK_OF_WEEK_BASED_YEAR = Field.WEEK_OF_WEEK_BASED_YEAR;
	/**
	* The field that represents the week-based-year.
	* <p>
	* This field allows the week-based-year value to be queried and set.
	* <p>
	* The field has a range that matches {@link LocalDate#MAX} and {@link LocalDate#MIN}.
	* <p>
	* In the resolving phase of parsing, a date can be created from a
	* week-based-year, week-of-week-based-year and day-of-week.
	* See {@link #WEEK_OF_WEEK_BASED_YEAR} for details.
	* <p>
	* This unit is an immutable and thread-safe singleton.
	*/
	public static final TemporalField WEEK_BASED_YEAR = Field.WEEK_BASED_YEAR;
	/**
	* The unit that represents week-based-years for the purpose of addition and subtraction.
	* <p>
	* This allows a number of week-based-years to be added to, or subtracted from, a date.
	* The unit is equal to either 52 or 53 weeks.
	* The estimated duration of a week-based-year is the same as that of a standard ISO
	* year at {@code 365.2425 Days}.
	* <p>
	* The rules for addition add the number of week-based-years to the existing value
	* for the week-based-year field. If the resulting week-based-year only has 52 weeks,
	* then the date will be in week 1 of the following week-based-year.
	* <p>
	* This unit is an immutable and thread-safe singleton.
	*/
	public static final TemporalUnit WEEK_BASED_YEARS = Unit.WEEK_BASED_YEARS;
	/**
	* Unit that represents the concept of a quarter-year.
	* For the ISO calendar system, it is equal to 3 months.
	* The estimated duration of a quarter-year is one quarter of {@code 365.2425 Days}.
	* <p>
	* This unit is an immutable and thread-safe singleton.
	*/
	public static final TemporalUnit QUARTER_YEARS = Unit.QUARTER_YEARS;

	/**
	* Restricted constructor.
	*/
	private IsoFields() {
	throw new AssertionError("Not instantiable");
	}

	//-----------------------------------------------------------------------
	/**
	* Implementation of the field.
	*/
	private static enum Field implements TemporalField {
	DAY_OF_QUARTER {
	@Override
	public TemporalUnit getBaseUnit() {
	return DAYS;
	}
	@Override
	public TemporalUnit getRangeUnit() {
	return QUARTER_YEARS;
	}
	@Override
	public ValueRange range() {
	return ValueRange.of(1, 90, 92);
	}
	@Override
	public boolean isSupportedBy(TemporalAccessor temporal) {
	return temporal.isSupported(DAY_OF_YEAR) && temporal.isSupported(MONTH_OF_YEAR) &&
	temporal.isSupported(YEAR) && isIso(temporal);
	}
	@Override
	public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
	if (isSupportedBy(temporal) == false) {
	throw new UnsupportedTemporalTypeException("Unsupported field: DayOfQuarter");
	}
	long qoy = temporal.getLong(QUARTER_OF_YEAR);
	if (qoy == 1) {
	long year = temporal.getLong(YEAR);
	return (IsoChronology.INSTANCE.isLeapYear(year) ? ValueRange.of(1, 91) : ValueRange.of(1, 90));
	} else if (qoy == 2) {
	return ValueRange.of(1, 91);
	} else if (qoy == 3 \|\| qoy == 4) {
	return ValueRange.of(1, 92);
	} // else value not from 1 to 4, so drop through
	return range();
	}
	@Override
	public long getFrom(TemporalAccessor temporal) {
	if (isSupportedBy(temporal) == false) {
	throw new UnsupportedTemporalTypeException("Unsupported field: DayOfQuarter");
	}
	int doy = temporal.get(DAY_OF_YEAR);
	int moy = temporal.get(MONTH_OF_YEAR);
	long year = temporal.getLong(YEAR);
	return doy - QUARTER_DAYS[((moy - 1) / 3) + (IsoChronology.INSTANCE.isLeapYear(year) ? 4 : 0)];
	}
	@SuppressWarnings("unchecked")
	@Override
	public <R extends Temporal> R adjustInto(R temporal, long newValue) {
	// calls getFrom() to check if supported
	long curValue = getFrom(temporal);
	range().checkValidValue(newValue, this); // leniently check from 1 to 92 TODO: check
	return (R) temporal.with(DAY_OF_YEAR, temporal.getLong(DAY_OF_YEAR) + (newValue - curValue));
	}
	@Override
	public ChronoLocalDate resolve(
	Map<TemporalField, Long> fieldValues, TemporalAccessor partialTemporal, ResolverStyle resolverStyle) {
	Long yearLong = fieldValues.get(YEAR);
	Long qoyLong = fieldValues.get(QUARTER_OF_YEAR);
	if (yearLong == null \|\| qoyLong == null) {
	return null;
	}
	int y = YEAR.checkValidIntValue(yearLong); // always validate
	long doq = fieldValues.get(DAY_OF_QUARTER);
	ensureIso(partialTemporal);
	LocalDate date;
	if (resolverStyle == ResolverStyle.LENIENT) {
	date = LocalDate.of(y, 1, 1).plusMonths(Math.multiplyExact(Math.subtractExact(qoyLong, 1), 3));
	doq = Math.subtractExact(doq, 1);
	} else {
	int qoy = QUARTER_OF_YEAR.range().checkValidIntValue(qoyLong, QUARTER_OF_YEAR); // validated
	date = LocalDate.of(y, ((qoy - 1) * 3) + 1, 1);
	if (doq < 1 \|\| doq > 90) {
	if (resolverStyle == ResolverStyle.STRICT) {
	rangeRefinedBy(date).checkValidValue(doq, this); // only allow exact range
	} else { // SMART
	range().checkValidValue(doq, this); // allow 1-92 rolling into next quarter
	}
	}
	doq--;
	}
	fieldValues.remove(this);
	fieldValues.remove(YEAR);
	fieldValues.remove(QUARTER_OF_YEAR);
	return date.plusDays(doq);
	}
	@Override
	public String toString() {
	return "DayOfQuarter";
	}
	},
	QUARTER_OF_YEAR {
	@Override
	public TemporalUnit getBaseUnit() {
	return QUARTER_YEARS;
	}
	@Override
	public TemporalUnit getRangeUnit() {
	return YEARS;
	}
	@Override
	public ValueRange range() {
	return ValueRange.of(1, 4);
	}
	@Override
	public boolean isSupportedBy(TemporalAccessor temporal) {
	return temporal.isSupported(MONTH_OF_YEAR) && isIso(temporal);
	}
	@Override
	public long getFrom(TemporalAccessor temporal) {
	if (isSupportedBy(temporal) == false) {
	throw new UnsupportedTemporalTypeException("Unsupported field: QuarterOfYear");
	}
	long moy = temporal.getLong(MONTH_OF_YEAR);
	return ((moy + 2) / 3);
	}
	@SuppressWarnings("unchecked")
	@Override
	public <R extends Temporal> R adjustInto(R temporal, long newValue) {
	// calls getFrom() to check if supported
	long curValue = getFrom(temporal);
	range().checkValidValue(newValue, this); // strictly check from 1 to 4
	return (R) temporal.with(MONTH_OF_YEAR, temporal.getLong(MONTH_OF_YEAR) + (newValue - curValue) * 3);
	}
	@Override
	public String toString() {
	return "QuarterOfYear";
	}
	},
	WEEK_OF_WEEK_BASED_YEAR {
	@Override
	public String getDisplayName(Locale locale) {
	Objects.requireNonNull(locale, "locale");
	LocaleResources lr = LocaleProviderAdapter.getResourceBundleBased()
	.getLocaleResources(locale);
	ResourceBundle rb = lr.getJavaTimeFormatData();
	return rb.containsKey("field.week") ? rb.getString("field.week") : toString();
	}

	@Override
	public TemporalUnit getBaseUnit() {
	return WEEKS;
	}
	@Override
	public TemporalUnit getRangeUnit() {
	return WEEK_BASED_YEARS;
	}
	@Override
	public ValueRange range() {
	return ValueRange.of(1, 52, 53);
	}
	@Override
	public boolean isSupportedBy(TemporalAccessor temporal) {
	return temporal.isSupported(EPOCH_DAY) && isIso(temporal);
	}
	@Override
	public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
	if (isSupportedBy(temporal) == false) {
	throw new UnsupportedTemporalTypeException("Unsupported field: WeekOfWeekBasedYear");
	}
	return getWeekRange(LocalDate.from(temporal));
	}
	@Override
	public long getFrom(TemporalAccessor temporal) {
	if (isSupportedBy(temporal) == false) {
	throw new UnsupportedTemporalTypeException("Unsupported field: WeekOfWeekBasedYear");
	}
	return getWeek(LocalDate.from(temporal));
	}
	@SuppressWarnings("unchecked")
	@Override
	public <R extends Temporal> R adjustInto(R temporal, long newValue) {
	// calls getFrom() to check if supported
	range().checkValidValue(newValue, this); // lenient range
	return (R) temporal.plus(Math.subtractExact(newValue, getFrom(temporal)), WEEKS);
	}
	@Override
	public ChronoLocalDate resolve(
	Map<TemporalField, Long> fieldValues, TemporalAccessor partialTemporal, ResolverStyle resolverStyle) {
	Long wbyLong = fieldValues.get(WEEK_BASED_YEAR);
	Long dowLong = fieldValues.get(DAY_OF_WEEK);
	if (wbyLong == null \|\| dowLong == null) {
	return null;
	}
	int wby = WEEK_BASED_YEAR.range().checkValidIntValue(wbyLong, WEEK_BASED_YEAR); // always validate
	long wowby = fieldValues.get(WEEK_OF_WEEK_BASED_YEAR);
	ensureIso(partialTemporal);
	LocalDate date = LocalDate.of(wby, 1, 4);
	if (resolverStyle == ResolverStyle.LENIENT) {
	long dow = dowLong; // unvalidated
	if (dow > 7) {
	date = date.plusWeeks((dow - 1) / 7);
	dow = ((dow - 1) % 7) + 1;
	} else if (dow < 1) {
	date = date.plusWeeks(Math.subtractExact(dow, 7) / 7);
	dow = ((dow + 6) % 7) + 1;
	}
	date = date.plusWeeks(Math.subtractExact(wowby, 1)).with(DAY_OF_WEEK, dow);
	} else {
	int dow = DAY_OF_WEEK.checkValidIntValue(dowLong); // validated
	if (wowby < 1 \|\| wowby > 52) {
	if (resolverStyle == ResolverStyle.STRICT) {
	getWeekRange(date).checkValidValue(wowby, this); // only allow exact range
	} else { // SMART
	range().checkValidValue(wowby, this); // allow 1-53 rolling into next year
	}
	}
	date = date.plusWeeks(wowby - 1).with(DAY_OF_WEEK, dow);
	}
	fieldValues.remove(this);
	fieldValues.remove(WEEK_BASED_YEAR);
	fieldValues.remove(DAY_OF_WEEK);
	return date;
	}
	@Override
	public String toString() {
	return "WeekOfWeekBasedYear";
	}
	},
	WEEK_BASED_YEAR {
	@Override
	public TemporalUnit getBaseUnit() {
	return WEEK_BASED_YEARS;
	}
	@Override
	public TemporalUnit getRangeUnit() {
	return FOREVER;
	}
	@Override
	public ValueRange range() {
	return YEAR.range();
	}
	@Override
	public boolean isSupportedBy(TemporalAccessor temporal) {
	return temporal.isSupported(EPOCH_DAY) && isIso(temporal);
	}
	@Override
	public long getFrom(TemporalAccessor temporal) {
	if (isSupportedBy(temporal) == false) {
	throw new UnsupportedTemporalTypeException("Unsupported field: WeekBasedYear");
	}
	return getWeekBasedYear(LocalDate.from(temporal));
	}
	@SuppressWarnings("unchecked")
	@Override
	public <R extends Temporal> R adjustInto(R temporal, long newValue) {
	if (isSupportedBy(temporal) == false) {
	throw new UnsupportedTemporalTypeException("Unsupported field: WeekBasedYear");
	}
	int newWby = range().checkValidIntValue(newValue, WEEK_BASED_YEAR); // strict check
	LocalDate date = LocalDate.from(temporal);
	int dow = date.get(DAY_OF_WEEK);
	int week = getWeek(date);
	if (week == 53 && getWeekRange(newWby) == 52) {
	week = 52;
	}
	LocalDate resolved = LocalDate.of(newWby, 1, 4); // 4th is guaranteed to be in week one
	int days = (dow - resolved.get(DAY_OF_WEEK)) + ((week - 1) * 7);
	resolved = resolved.plusDays(days);
	return (R) temporal.with(resolved);
	}
	@Override
	public String toString() {
	return "WeekBasedYear";
	}
	};

	@Override
	public boolean isDateBased() {
	return true;
	}

	@Override
	public boolean isTimeBased() {
	return false;
	}

	@Override
	public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
	return range();
	}

	//-------------------------------------------------------------------------
	private static final int[] QUARTER_DAYS = {0, 90, 181, 273, 0, 91, 182, 274};

	private static boolean isIso(TemporalAccessor temporal) {
	return Chronology.from(temporal).equals(IsoChronology.INSTANCE);
	}

	private static void ensureIso(TemporalAccessor temporal) {
	if (isIso(temporal) == false) {
	throw new DateTimeException("Resolve requires IsoChronology");
	}
	}

	private static ValueRange getWeekRange(LocalDate date) {
	int wby = getWeekBasedYear(date);
	return ValueRange.of(1, getWeekRange(wby));
	}

	private static int getWeekRange(int wby) {
	LocalDate date = LocalDate.of(wby, 1, 1);
	// 53 weeks if standard year starts on Thursday, or Wed in a leap year
	if (date.getDayOfWeek() == THURSDAY \|\| (date.getDayOfWeek() == WEDNESDAY && date.isLeapYear())) {
	return 53;
	}
	return 52;
	}

	private static int getWeek(LocalDate date) {
	int dow0 = date.getDayOfWeek().ordinal();
	int doy0 = date.getDayOfYear() - 1;
	int doyThu0 = doy0 + (3 - dow0); // adjust to mid-week Thursday (which is 3 indexed from zero)
	int alignedWeek = doyThu0 / 7;
	int firstThuDoy0 = doyThu0 - (alignedWeek * 7);
	int firstMonDoy0 = firstThuDoy0 - 3;
	if (firstMonDoy0 < -3) {
	firstMonDoy0 += 7;
	}
	if (doy0 < firstMonDoy0) {
	return (int) getWeekRange(date.withDayOfYear(180).minusYears(1)).getMaximum();
	}
	int week = ((doy0 - firstMonDoy0) / 7) + 1;
	if (week == 53) {
	if ((firstMonDoy0 == -3 \|\| (firstMonDoy0 == -2 && date.isLeapYear())) == false) {
	week = 1;
	}
	}
	return week;
	}

	private static int getWeekBasedYear(LocalDate date) {
	int year = date.getYear();
	int doy = date.getDayOfYear();
	if (doy <= 3) {
	int dow = date.getDayOfWeek().ordinal();
	if (doy - dow < -2) {
	year--;
	}
	} else if (doy >= 363) {
	int dow = date.getDayOfWeek().ordinal();
	doy = doy - 363 - (date.isLeapYear() ? 1 : 0);
	if (doy - dow >= 0) {
	year++;
	}
	}
	return year;
	}
	}

	//-----------------------------------------------------------------------
	/**
	* Implementation of the unit.
	*/
	private static enum Unit implements TemporalUnit {

	/**
	* Unit that represents the concept of a week-based-year.
	*/
	WEEK_BASED_YEARS("WeekBasedYears", Duration.ofSeconds(31556952L)),
	/**
	* Unit that represents the concept of a quarter-year.
	*/
	QUARTER_YEARS("QuarterYears", Duration.ofSeconds(31556952L / 4));

	private final String name;
	private final Duration duration;

	private Unit(String name, Duration estimatedDuration) {
	this.name = name;
	this.duration = estimatedDuration;
	}

	@Override
	public Duration getDuration() {
	return duration;
	}

	@Override
	public boolean isDurationEstimated() {
	return true;
	}

	@Override
	public boolean isDateBased() {
	return true;
	}

	@Override
	public boolean isTimeBased() {
	return false;
	}

	@Override
	public boolean isSupportedBy(Temporal temporal) {
	return temporal.isSupported(EPOCH_DAY);
	}

	@SuppressWarnings("unchecked")
	@Override
	public <R extends Temporal> R addTo(R temporal, long amount) {
	switch (this) {
	case WEEK_BASED_YEARS:
	return (R) temporal.with(WEEK_BASED_YEAR,
	Math.addExact(temporal.get(WEEK_BASED_YEAR), amount));
	case QUARTER_YEARS:
	return (R) temporal.plus(amount / 4, YEARS)
	.plus((amount % 4) * 3, MONTHS);
	default:
	throw new IllegalStateException("Unreachable");
	}
	}

	@Override
	public long between(Temporal temporal1Inclusive, Temporal temporal2Exclusive) {
	if (temporal1Inclusive.getClass() != temporal2Exclusive.getClass()) {
	return temporal1Inclusive.until(temporal2Exclusive, this);
	}
	switch(this) {
	case WEEK_BASED_YEARS:
	return Math.subtractExact(temporal2Exclusive.getLong(WEEK_BASED_YEAR),
	temporal1Inclusive.getLong(WEEK_BASED_YEAR));
	case QUARTER_YEARS:
	return temporal1Inclusive.until(temporal2Exclusive, MONTHS) / 3;
	default:
	throw new IllegalStateException("Unreachable");
	}
	}

	@Override
	public String toString() {
	return name;
	}
	}
	}

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