8040058: IsoFields.WEEK_BASED_YEAR adjustInto incorrect and WeekFields.weekOfWeekBasedYear().range incorrect
Reviewed-by: lancea, rriggs
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/*
* Copyright (c) 2011-2012, Stephen Colebourne & Michael Nascimento Santos
*
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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 period 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:
// no overflow (256 is multiple of 4)
return (R) temporal.plus(amount / 256, YEARS)
.plus((amount % 256) * 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;
}
}
}