1 /*
2  * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
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11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
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17  * You should have received a copy of the GNU General Public License version
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25 
26 /*
27  * Copyright (c) 2011-2012, Stephen Colebourne & Michael Nascimento Santos
28  *
29  * All rights reserved.
30  *
31  * Redistribution and use in source and binary forms, with or without
32  * modification, are permitted provided that the following conditions are met:
33  *
34  *  * Redistributions of source code must retain the above copyright notice,
35  *    this list of conditions and the following disclaimer.
36  *
37  *  * Redistributions in binary form must reproduce the above copyright notice,
38  *    this list of conditions and the following disclaimer in the documentation
39  *    and/or other materials provided with the distribution.
40  *
41  *  * Neither the name of JSR-310 nor the names of its contributors
42  *    may be used to endorse or promote products derived from this software
43  *    without specific prior written permission.
44  *
45  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
46  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
47  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
48  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
49  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
50  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
51  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
52  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
53  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
54  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
55  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56  */
57 package java.time.temporal;
58 
59 import android.icu.text.DateTimePatternGenerator;
60 import android.icu.util.ULocale;
61 
62 import static java.time.DayOfWeek.THURSDAY;
63 import static java.time.DayOfWeek.WEDNESDAY;
64 import static java.time.temporal.ChronoField.DAY_OF_WEEK;
65 import static java.time.temporal.ChronoField.DAY_OF_YEAR;
66 import static java.time.temporal.ChronoField.EPOCH_DAY;
67 import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
68 import static java.time.temporal.ChronoField.YEAR;
69 import static java.time.temporal.ChronoUnit.DAYS;
70 import static java.time.temporal.ChronoUnit.FOREVER;
71 import static java.time.temporal.ChronoUnit.MONTHS;
72 import static java.time.temporal.ChronoUnit.WEEKS;
73 import static java.time.temporal.ChronoUnit.YEARS;
74 
75 import java.time.DateTimeException;
76 import java.time.Duration;
77 import java.time.LocalDate;
78 import java.time.chrono.ChronoLocalDate;
79 import java.time.chrono.Chronology;
80 import java.time.chrono.IsoChronology;
81 import java.time.format.ResolverStyle;
82 import java.util.Locale;
83 import java.util.Map;
84 import java.util.Objects;
85 import java.util.ResourceBundle;
86 
87 import sun.util.locale.provider.CalendarDataUtility;
88 
89 /**
90  * Fields and units specific to the ISO-8601 calendar system,
91  * including quarter-of-year and week-based-year.
92  * <p>
93  * This class defines fields and units that are specific to the ISO calendar system.
94  *
95  * <h2>Quarter of year</h2>
96  * The ISO-8601 standard is based on the standard civic 12 month year.
97  * This is commonly divided into four quarters, often abbreviated as Q1, Q2, Q3 and Q4.
98  * <p>
99  * January, February and March are in Q1.
100  * April, May and June are in Q2.
101  * July, August and September are in Q3.
102  * October, November and December are in Q4.
103  * <p>
104  * The complete date is expressed using three fields:
105  * <ul>
106  * <li>{@link #DAY_OF_QUARTER DAY_OF_QUARTER} - the day within the quarter, from 1 to 90, 91 or 92
107  * <li>{@link #QUARTER_OF_YEAR QUARTER_OF_YEAR} - the quarter within the year, from 1 to 4
108  * <li>{@link ChronoField#YEAR YEAR} - the standard ISO year
109  * </ul>
110  *
111  * <h2>Week based years</h2>
112  * The ISO-8601 standard was originally intended as a data interchange format,
113  * defining a string format for dates and times. However, it also defines an
114  * alternate way of expressing the date, based on the concept of week-based-year.
115  * <p>
116  * The date is expressed using three fields:
117  * <ul>
118  * <li>{@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} - the standard field defining the
119  *  day-of-week from Monday (1) to Sunday (7)
120  * <li>{@link #WEEK_OF_WEEK_BASED_YEAR} - the week within the week-based-year
121  * <li>{@link #WEEK_BASED_YEAR WEEK_BASED_YEAR} - the week-based-year
122  * </ul>
123  * The week-based-year itself is defined relative to the standard ISO proleptic year.
124  * It differs from the standard year in that it always starts on a Monday.
125  * <p>
126  * The first week of a week-based-year is the first Monday-based week of the standard
127  * ISO year that has at least 4 days in the new year.
128  * <ul>
129  * <li>If January 1st is Monday then week 1 starts on January 1st
130  * <li>If January 1st is Tuesday then week 1 starts on December 31st of the previous standard year
131  * <li>If January 1st is Wednesday then week 1 starts on December 30th of the previous standard year
132  * <li>If January 1st is Thursday then week 1 starts on December 29th of the previous standard year
133  * <li>If January 1st is Friday then week 1 starts on January 4th
134  * <li>If January 1st is Saturday then week 1 starts on January 3rd
135  * <li>If January 1st is Sunday then week 1 starts on January 2nd
136  * </ul>
137  * There are 52 weeks in most week-based years, however on occasion there are 53 weeks.
138  * <p>
139  * For example:
140  *
141  * <table class=striped style="text-align: left">
142  * <caption>Examples of Week based Years</caption>
143  * <thead>
144  * <tr><th scope="col">Date</th><th scope="col">Day-of-week</th><th scope="col">Field values</th></tr>
145  * </thead>
146  * <tbody>
147  * <tr><th scope="row">2008-12-28</th><td>Sunday</td><td>Week 52 of week-based-year 2008</td></tr>
148  * <tr><th scope="row">2008-12-29</th><td>Monday</td><td>Week 1 of week-based-year 2009</td></tr>
149  * <tr><th scope="row">2008-12-31</th><td>Wednesday</td><td>Week 1 of week-based-year 2009</td></tr>
150  * <tr><th scope="row">2009-01-01</th><td>Thursday</td><td>Week 1 of week-based-year 2009</td></tr>
151  * <tr><th scope="row">2009-01-04</th><td>Sunday</td><td>Week 1 of week-based-year 2009</td></tr>
152  * <tr><th scope="row">2009-01-05</th><td>Monday</td><td>Week 2 of week-based-year 2009</td></tr>
153  * </tbody>
154  * </table>
155  *
156  * @implSpec
157  * <p>
158  * This class is immutable and thread-safe.
159  *
160  * @since 1.8
161  */
162 public final class IsoFields {
163 
164     /**
165      * The field that represents the day-of-quarter.
166      * <p>
167      * This field allows the day-of-quarter value to be queried and set.
168      * The day-of-quarter has values from 1 to 90 in Q1 of a standard year, from 1 to 91
169      * in Q1 of a leap year, from 1 to 91 in Q2 and from 1 to 92 in Q3 and Q4.
170      * <p>
171      * The day-of-quarter can only be calculated if the day-of-year, month-of-year and year
172      * are available.
173      * <p>
174      * When setting this field, the value is allowed to be partially lenient, taking any
175      * value from 1 to 92. If the quarter has less than 92 days, then day 92, and
176      * potentially day 91, is in the following quarter.
177      * <p>
178      * In the resolving phase of parsing, a date can be created from a year,
179      * quarter-of-year and day-of-quarter.
180      * <p>
181      * In {@linkplain ResolverStyle#STRICT strict mode}, all three fields are
182      * validated against their range of valid values. The day-of-quarter field
183      * is validated from 1 to 90, 91 or 92 depending on the year and quarter.
184      * <p>
185      * In {@linkplain ResolverStyle#SMART smart mode}, all three fields are
186      * validated against their range of valid values. The day-of-quarter field is
187      * validated between 1 and 92, ignoring the actual range based on the year and quarter.
188      * If the day-of-quarter exceeds the actual range by one day, then the resulting date
189      * is one day later. If the day-of-quarter exceeds the actual range by two days,
190      * then the resulting date is two days later.
191      * <p>
192      * In {@linkplain ResolverStyle#LENIENT lenient mode}, only the year is validated
193      * against the range of valid values. The resulting date is calculated equivalent to
194      * the following three stage approach. First, create a date on the first of January
195      * in the requested year. Then take the quarter-of-year, subtract one, and add the
196      * amount in quarters to the date. Finally, take the day-of-quarter, subtract one,
197      * and add the amount in days to the date.
198      * <p>
199      * This unit is an immutable and thread-safe singleton.
200      */
201     public static final TemporalField DAY_OF_QUARTER = Field.DAY_OF_QUARTER;
202     /**
203      * The field that represents the quarter-of-year.
204      * <p>
205      * This field allows the quarter-of-year value to be queried and set.
206      * The quarter-of-year has values from 1 to 4.
207      * <p>
208      * The quarter-of-year can only be calculated if the month-of-year is available.
209      * <p>
210      * In the resolving phase of parsing, a date can be created from a year,
211      * quarter-of-year and day-of-quarter.
212      * See {@link #DAY_OF_QUARTER} for details.
213      * <p>
214      * This unit is an immutable and thread-safe singleton.
215      */
216     public static final TemporalField QUARTER_OF_YEAR = Field.QUARTER_OF_YEAR;
217     /**
218      * The field that represents the week-of-week-based-year.
219      * <p>
220      * This field allows the week of the week-based-year value to be queried and set.
221      * The week-of-week-based-year has values from 1 to 52, or 53 if the
222      * week-based-year has 53 weeks.
223      * <p>
224      * In the resolving phase of parsing, a date can be created from a
225      * week-based-year, week-of-week-based-year and day-of-week.
226      * <p>
227      * In {@linkplain ResolverStyle#STRICT strict mode}, all three fields are
228      * validated against their range of valid values. The week-of-week-based-year
229      * field is validated from 1 to 52 or 53 depending on the week-based-year.
230      * <p>
231      * In {@linkplain ResolverStyle#SMART smart mode}, all three fields are
232      * validated against their range of valid values. The week-of-week-based-year
233      * field is validated between 1 and 53, ignoring the week-based-year.
234      * If the week-of-week-based-year is 53, but the week-based-year only has
235      * 52 weeks, then the resulting date is in week 1 of the following week-based-year.
236      * <p>
237      * In {@linkplain ResolverStyle#LENIENT lenient mode}, only the week-based-year
238      * is validated against the range of valid values. If the day-of-week is outside
239      * the range 1 to 7, then the resulting date is adjusted by a suitable number of
240      * weeks to reduce the day-of-week to the range 1 to 7. If the week-of-week-based-year
241      * value is outside the range 1 to 52, then any excess weeks are added or subtracted
242      * from the resulting date.
243      * <p>
244      * This unit is an immutable and thread-safe singleton.
245      */
246     public static final TemporalField WEEK_OF_WEEK_BASED_YEAR = Field.WEEK_OF_WEEK_BASED_YEAR;
247     /**
248      * The field that represents the week-based-year.
249      * <p>
250      * This field allows the week-based-year value to be queried and set.
251      * <p>
252      * The field has a range that matches {@link LocalDate#MAX} and {@link LocalDate#MIN}.
253      * <p>
254      * In the resolving phase of parsing, a date can be created from a
255      * week-based-year, week-of-week-based-year and day-of-week.
256      * See {@link #WEEK_OF_WEEK_BASED_YEAR} for details.
257      * <p>
258      * This unit is an immutable and thread-safe singleton.
259      */
260     public static final TemporalField WEEK_BASED_YEAR = Field.WEEK_BASED_YEAR;
261     /**
262      * The unit that represents week-based-years for the purpose of addition and subtraction.
263      * <p>
264      * This allows a number of week-based-years to be added to, or subtracted from, a date.
265      * The unit is equal to either 52 or 53 weeks.
266      * The estimated duration of a week-based-year is the same as that of a standard ISO
267      * year at {@code 365.2425 Days}.
268      * <p>
269      * The rules for addition add the number of week-based-years to the existing value
270      * for the week-based-year field. If the resulting week-based-year only has 52 weeks,
271      * then the date will be in week 1 of the following week-based-year.
272      * <p>
273      * This unit is an immutable and thread-safe singleton.
274      */
275     public static final TemporalUnit WEEK_BASED_YEARS = Unit.WEEK_BASED_YEARS;
276     /**
277      * Unit that represents the concept of a quarter-year.
278      * For the ISO calendar system, it is equal to 3 months.
279      * The estimated duration of a quarter-year is one quarter of {@code 365.2425 Days}.
280      * <p>
281      * This unit is an immutable and thread-safe singleton.
282      */
283     public static final TemporalUnit QUARTER_YEARS = Unit.QUARTER_YEARS;
284 
285     /**
286      * Restricted constructor.
287      */
IsoFields()288     private IsoFields() {
289         throw new AssertionError("Not instantiable");
290     }
291 
292     //-----------------------------------------------------------------------
293     /**
294      * Implementation of the field.
295      */
296     private static enum Field implements TemporalField {
297         DAY_OF_QUARTER {
298             @Override
getBaseUnit()299             public TemporalUnit getBaseUnit() {
300                 return DAYS;
301             }
302             @Override
getRangeUnit()303             public TemporalUnit getRangeUnit() {
304                 return QUARTER_YEARS;
305             }
306             @Override
range()307             public ValueRange range() {
308                 return ValueRange.of(1, 90, 92);
309             }
310             @Override
isSupportedBy(TemporalAccessor temporal)311             public boolean isSupportedBy(TemporalAccessor temporal) {
312                 return temporal.isSupported(DAY_OF_YEAR) && temporal.isSupported(MONTH_OF_YEAR) &&
313                         temporal.isSupported(YEAR) && isIso(temporal);
314             }
315             @Override
rangeRefinedBy(TemporalAccessor temporal)316             public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
317                 if (isSupportedBy(temporal) == false) {
318                     throw new UnsupportedTemporalTypeException("Unsupported field: DayOfQuarter");
319                 }
320                 long qoy = temporal.getLong(QUARTER_OF_YEAR);
321                 if (qoy == 1) {
322                     long year = temporal.getLong(YEAR);
323                     return (IsoChronology.INSTANCE.isLeapYear(year) ? ValueRange.of(1, 91) : ValueRange.of(1, 90));
324                 } else if (qoy == 2) {
325                     return ValueRange.of(1, 91);
326                 } else if (qoy == 3 || qoy == 4) {
327                     return ValueRange.of(1, 92);
328                 } // else value not from 1 to 4, so drop through
329                 return range();
330             }
331             @Override
getFrom(TemporalAccessor temporal)332             public long getFrom(TemporalAccessor temporal) {
333                 if (isSupportedBy(temporal) == false) {
334                     throw new UnsupportedTemporalTypeException("Unsupported field: DayOfQuarter");
335                 }
336                 int doy = temporal.get(DAY_OF_YEAR);
337                 int moy = temporal.get(MONTH_OF_YEAR);
338                 long year = temporal.getLong(YEAR);
339                 return doy - QUARTER_DAYS[((moy - 1) / 3) + (IsoChronology.INSTANCE.isLeapYear(year) ? 4 : 0)];
340             }
341             @SuppressWarnings("unchecked")
342             @Override
adjustInto(R temporal, long newValue)343             public <R extends Temporal> R adjustInto(R temporal, long newValue) {
344                 // calls getFrom() to check if supported
345                 long curValue = getFrom(temporal);
346                 range().checkValidValue(newValue, this);  // leniently check from 1 to 92 TODO: check
347                 return (R) temporal.with(DAY_OF_YEAR, temporal.getLong(DAY_OF_YEAR) + (newValue - curValue));
348             }
349             @Override
resolve( Map<TemporalField, Long> fieldValues, TemporalAccessor partialTemporal, ResolverStyle resolverStyle)350             public ChronoLocalDate resolve(
351                     Map<TemporalField, Long> fieldValues, TemporalAccessor partialTemporal, ResolverStyle resolverStyle) {
352                 Long yearLong = fieldValues.get(YEAR);
353                 Long qoyLong = fieldValues.get(QUARTER_OF_YEAR);
354                 if (yearLong == null || qoyLong == null) {
355                     return null;
356                 }
357                 int y = YEAR.checkValidIntValue(yearLong);  // always validate
358                 long doq = fieldValues.get(DAY_OF_QUARTER);
359                 ensureIso(partialTemporal);
360                 LocalDate date;
361                 if (resolverStyle == ResolverStyle.LENIENT) {
362                     date = LocalDate.of(y, 1, 1).plusMonths(Math.multiplyExact(Math.subtractExact(qoyLong, 1), 3));
363                     doq = Math.subtractExact(doq, 1);
364                 } else {
365                     int qoy = QUARTER_OF_YEAR.range().checkValidIntValue(qoyLong, QUARTER_OF_YEAR);  // validated
366                     date = LocalDate.of(y, ((qoy - 1) * 3) + 1, 1);
367                     if (doq < 1 || doq > 90) {
368                         if (resolverStyle == ResolverStyle.STRICT) {
369                             rangeRefinedBy(date).checkValidValue(doq, this);  // only allow exact range
370                         } else {  // SMART
371                             range().checkValidValue(doq, this);  // allow 1-92 rolling into next quarter
372                         }
373                     }
374                     doq--;
375                 }
376                 fieldValues.remove(this);
377                 fieldValues.remove(YEAR);
378                 fieldValues.remove(QUARTER_OF_YEAR);
379                 return date.plusDays(doq);
380             }
381             @Override
toString()382             public String toString() {
383                 return "DayOfQuarter";
384             }
385         },
386         QUARTER_OF_YEAR {
387             @Override
getBaseUnit()388             public TemporalUnit getBaseUnit() {
389                 return QUARTER_YEARS;
390             }
391             @Override
getRangeUnit()392             public TemporalUnit getRangeUnit() {
393                 return YEARS;
394             }
395             @Override
range()396             public ValueRange range() {
397                 return ValueRange.of(1, 4);
398             }
399             @Override
isSupportedBy(TemporalAccessor temporal)400             public boolean isSupportedBy(TemporalAccessor temporal) {
401                 return temporal.isSupported(MONTH_OF_YEAR) && isIso(temporal);
402             }
403             @Override
getFrom(TemporalAccessor temporal)404             public long getFrom(TemporalAccessor temporal) {
405                 if (isSupportedBy(temporal) == false) {
406                     throw new UnsupportedTemporalTypeException("Unsupported field: QuarterOfYear");
407                 }
408                 long moy = temporal.getLong(MONTH_OF_YEAR);
409                 return ((moy + 2) / 3);
410             }
rangeRefinedBy(TemporalAccessor temporal)411             public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
412                 if (isSupportedBy(temporal) == false) {
413                     throw new UnsupportedTemporalTypeException("Unsupported field: QuarterOfYear");
414                 }
415                 return super.rangeRefinedBy(temporal);
416             }
417             @SuppressWarnings("unchecked")
418             @Override
adjustInto(R temporal, long newValue)419             public <R extends Temporal> R adjustInto(R temporal, long newValue) {
420                 // calls getFrom() to check if supported
421                 long curValue = getFrom(temporal);
422                 range().checkValidValue(newValue, this);  // strictly check from 1 to 4
423                 return (R) temporal.with(MONTH_OF_YEAR, temporal.getLong(MONTH_OF_YEAR) + (newValue - curValue) * 3);
424             }
425             @Override
toString()426             public String toString() {
427                 return "QuarterOfYear";
428             }
429         },
430         WEEK_OF_WEEK_BASED_YEAR {
431             @Override
getDisplayName(Locale locale)432             public String getDisplayName(Locale locale) {
433                 Objects.requireNonNull(locale, "locale");
434                 // BEGIN Android-changed: Use ICU name values.
435                 /*
436                 LocaleResources lr = LocaleProviderAdapter.getResourceBundleBased()
437                                             .getLocaleResources(
438                                                 CalendarDataUtility
439                                                     .findRegionOverride(locale));
440                 ResourceBundle rb = lr.getJavaTimeFormatData();
441                 return rb.containsKey("field.week") ? rb.getString("field.week") : toString();
442                  */
443                 DateTimePatternGenerator dateTimePatternGenerator = DateTimePatternGenerator
444                         .getInstance(ULocale.forLocale(locale));
445                 String icuName = dateTimePatternGenerator
446                         .getAppendItemName(DateTimePatternGenerator.WEEK_OF_YEAR);
447                 return icuName != null && !icuName.isEmpty() ? icuName : toString();
448                 // END Android-changed: Use ICU name values.
449             }
450 
451             @Override
getBaseUnit()452             public TemporalUnit getBaseUnit() {
453                 return WEEKS;
454             }
455             @Override
getRangeUnit()456             public TemporalUnit getRangeUnit() {
457                 return WEEK_BASED_YEARS;
458             }
459             @Override
range()460             public ValueRange range() {
461                 return ValueRange.of(1, 52, 53);
462             }
463             @Override
isSupportedBy(TemporalAccessor temporal)464             public boolean isSupportedBy(TemporalAccessor temporal) {
465                 return temporal.isSupported(EPOCH_DAY) && isIso(temporal);
466             }
467             @Override
rangeRefinedBy(TemporalAccessor temporal)468             public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
469                 if (isSupportedBy(temporal) == false) {
470                     throw new UnsupportedTemporalTypeException("Unsupported field: WeekOfWeekBasedYear");
471                 }
472                 return getWeekRange(LocalDate.from(temporal));
473             }
474             @Override
getFrom(TemporalAccessor temporal)475             public long getFrom(TemporalAccessor temporal) {
476                 if (isSupportedBy(temporal) == false) {
477                     throw new UnsupportedTemporalTypeException("Unsupported field: WeekOfWeekBasedYear");
478                 }
479                 return getWeek(LocalDate.from(temporal));
480             }
481             @SuppressWarnings("unchecked")
482             @Override
adjustInto(R temporal, long newValue)483             public <R extends Temporal> R adjustInto(R temporal, long newValue) {
484                 // calls getFrom() to check if supported
485                 range().checkValidValue(newValue, this);  // lenient range
486                 return (R) temporal.plus(Math.subtractExact(newValue, getFrom(temporal)), WEEKS);
487             }
488             @Override
resolve( Map<TemporalField, Long> fieldValues, TemporalAccessor partialTemporal, ResolverStyle resolverStyle)489             public ChronoLocalDate resolve(
490                     Map<TemporalField, Long> fieldValues, TemporalAccessor partialTemporal, ResolverStyle resolverStyle) {
491                 Long wbyLong = fieldValues.get(WEEK_BASED_YEAR);
492                 Long dowLong = fieldValues.get(DAY_OF_WEEK);
493                 if (wbyLong == null || dowLong == null) {
494                     return null;
495                 }
496                 int wby = WEEK_BASED_YEAR.range().checkValidIntValue(wbyLong, WEEK_BASED_YEAR);  // always validate
497                 long wowby = fieldValues.get(WEEK_OF_WEEK_BASED_YEAR);
498                 ensureIso(partialTemporal);
499                 LocalDate date = LocalDate.of(wby, 1, 4);
500                 if (resolverStyle == ResolverStyle.LENIENT) {
501                     long dow = dowLong;  // unvalidated
502                     if (dow > 7) {
503                         date = date.plusWeeks((dow - 1) / 7);
504                         dow = ((dow - 1) % 7) + 1;
505                     } else if (dow < 1) {
506                         date = date.plusWeeks(Math.subtractExact(dow,  7) / 7);
507                         dow = ((dow + 6) % 7) + 1;
508                     }
509                     date = date.plusWeeks(Math.subtractExact(wowby, 1)).with(DAY_OF_WEEK, dow);
510                 } else {
511                     int dow = DAY_OF_WEEK.checkValidIntValue(dowLong);  // validated
512                     if (wowby < 1 || wowby > 52) {
513                         if (resolverStyle == ResolverStyle.STRICT) {
514                             getWeekRange(date).checkValidValue(wowby, this);  // only allow exact range
515                         } else {  // SMART
516                             range().checkValidValue(wowby, this);  // allow 1-53 rolling into next year
517                         }
518                     }
519                     date = date.plusWeeks(wowby - 1).with(DAY_OF_WEEK, dow);
520                 }
521                 fieldValues.remove(this);
522                 fieldValues.remove(WEEK_BASED_YEAR);
523                 fieldValues.remove(DAY_OF_WEEK);
524                 return date;
525             }
526             @Override
toString()527             public String toString() {
528                 return "WeekOfWeekBasedYear";
529             }
530         },
531         WEEK_BASED_YEAR {
532             @Override
getBaseUnit()533             public TemporalUnit getBaseUnit() {
534                 return WEEK_BASED_YEARS;
535             }
536             @Override
getRangeUnit()537             public TemporalUnit getRangeUnit() {
538                 return FOREVER;
539             }
540             @Override
range()541             public ValueRange range() {
542                 return YEAR.range();
543             }
544             @Override
isSupportedBy(TemporalAccessor temporal)545             public boolean isSupportedBy(TemporalAccessor temporal) {
546                 return temporal.isSupported(EPOCH_DAY) && isIso(temporal);
547             }
548             @Override
getFrom(TemporalAccessor temporal)549             public long getFrom(TemporalAccessor temporal) {
550                 if (isSupportedBy(temporal) == false) {
551                     throw new UnsupportedTemporalTypeException("Unsupported field: WeekBasedYear");
552                 }
553                 return getWeekBasedYear(LocalDate.from(temporal));
554             }
rangeRefinedBy(TemporalAccessor temporal)555             public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
556                 if (isSupportedBy(temporal) == false) {
557                     throw new UnsupportedTemporalTypeException("Unsupported field: WeekBasedYear");
558                 }
559                 return super.rangeRefinedBy(temporal);
560             }
561             @SuppressWarnings("unchecked")
562             @Override
adjustInto(R temporal, long newValue)563             public <R extends Temporal> R adjustInto(R temporal, long newValue) {
564                 if (isSupportedBy(temporal) == false) {
565                     throw new UnsupportedTemporalTypeException("Unsupported field: WeekBasedYear");
566                 }
567                 int newWby = range().checkValidIntValue(newValue, WEEK_BASED_YEAR);  // strict check
568                 LocalDate date = LocalDate.from(temporal);
569                 int dow = date.get(DAY_OF_WEEK);
570                 int week = getWeek(date);
571                 if (week == 53 && getWeekRange(newWby) == 52) {
572                     week = 52;
573                 }
574                 LocalDate resolved = LocalDate.of(newWby, 1, 4);  // 4th is guaranteed to be in week one
575                 int days = (dow - resolved.get(DAY_OF_WEEK)) + ((week - 1) * 7);
576                 resolved = resolved.plusDays(days);
577                 return (R) temporal.with(resolved);
578             }
579             @Override
toString()580             public String toString() {
581                 return "WeekBasedYear";
582             }
583         };
584 
585         @Override
isDateBased()586         public boolean isDateBased() {
587             return true;
588         }
589 
590         @Override
isTimeBased()591         public boolean isTimeBased() {
592             return false;
593         }
594 
595         @Override
rangeRefinedBy(TemporalAccessor temporal)596         public ValueRange rangeRefinedBy(TemporalAccessor temporal) {
597             return range();
598         }
599 
600         //-------------------------------------------------------------------------
601         private static final int[] QUARTER_DAYS = {0, 90, 181, 273, 0, 91, 182, 274};
602 
603 
ensureIso(TemporalAccessor temporal)604         private static void ensureIso(TemporalAccessor temporal) {
605             if (isIso(temporal) == false) {
606                 throw new DateTimeException("Resolve requires IsoChronology");
607             }
608         }
609 
getWeekRange(LocalDate date)610         private static ValueRange getWeekRange(LocalDate date) {
611             int wby = getWeekBasedYear(date);
612             return ValueRange.of(1, getWeekRange(wby));
613         }
614 
getWeekRange(int wby)615         private static int getWeekRange(int wby) {
616             LocalDate date = LocalDate.of(wby, 1, 1);
617             // 53 weeks if standard year starts on Thursday, or Wed in a leap year
618             if (date.getDayOfWeek() == THURSDAY || (date.getDayOfWeek() == WEDNESDAY && date.isLeapYear())) {
619                 return 53;
620             }
621             return 52;
622         }
623 
getWeek(LocalDate date)624         private static int getWeek(LocalDate date) {
625             int dow0 = date.getDayOfWeek().ordinal();
626             int doy0 = date.getDayOfYear() - 1;
627             int doyThu0 = doy0 + (3 - dow0);  // adjust to mid-week Thursday (which is 3 indexed from zero)
628             int alignedWeek = doyThu0 / 7;
629             int firstThuDoy0 = doyThu0 - (alignedWeek * 7);
630             int firstMonDoy0 = firstThuDoy0 - 3;
631             if (firstMonDoy0 < -3) {
632                 firstMonDoy0 += 7;
633             }
634             if (doy0 < firstMonDoy0) {
635                 return (int) getWeekRange(date.withDayOfYear(180).minusYears(1)).getMaximum();
636             }
637             int week = ((doy0 - firstMonDoy0) / 7) + 1;
638             if (week == 53) {
639                 if ((firstMonDoy0 == -3 || (firstMonDoy0 == -2 && date.isLeapYear())) == false) {
640                     week = 1;
641                 }
642             }
643             return week;
644         }
645 
getWeekBasedYear(LocalDate date)646         private static int getWeekBasedYear(LocalDate date) {
647             int year = date.getYear();
648             int doy = date.getDayOfYear();
649             if (doy <= 3) {
650                 int dow = date.getDayOfWeek().ordinal();
651                 if (doy - dow < -2) {
652                     year--;
653                 }
654             } else if (doy >= 363) {
655                 int dow = date.getDayOfWeek().ordinal();
656                 doy = doy - 363 - (date.isLeapYear() ? 1 : 0);
657                 if (doy - dow >= 0) {
658                     year++;
659                 }
660             }
661             return year;
662         }
663     }
664 
665     //-----------------------------------------------------------------------
666     /**
667      * Implementation of the unit.
668      */
669     private static enum Unit implements TemporalUnit {
670 
671         /**
672          * Unit that represents the concept of a week-based-year.
673          */
674         WEEK_BASED_YEARS("WeekBasedYears", Duration.ofSeconds(31556952L)),
675         /**
676          * Unit that represents the concept of a quarter-year.
677          */
678         QUARTER_YEARS("QuarterYears", Duration.ofSeconds(31556952L / 4));
679 
680         private final String name;
681         private final Duration duration;
682 
Unit(String name, Duration estimatedDuration)683         private Unit(String name, Duration estimatedDuration) {
684             this.name = name;
685             this.duration = estimatedDuration;
686         }
687 
688         @Override
getDuration()689         public Duration getDuration() {
690             return duration;
691         }
692 
693         @Override
isDurationEstimated()694         public boolean isDurationEstimated() {
695             return true;
696         }
697 
698         @Override
isDateBased()699         public boolean isDateBased() {
700             return true;
701         }
702 
703         @Override
isTimeBased()704         public boolean isTimeBased() {
705             return false;
706         }
707 
708         @Override
isSupportedBy(Temporal temporal)709         public boolean isSupportedBy(Temporal temporal) {
710             return temporal.isSupported(EPOCH_DAY) && isIso(temporal);
711         }
712 
713         @SuppressWarnings("unchecked")
714         @Override
addTo(R temporal, long amount)715         public <R extends Temporal> R addTo(R temporal, long amount) {
716             switch (this) {
717                 case WEEK_BASED_YEARS:
718                     return (R) temporal.with(WEEK_BASED_YEAR,
719                             Math.addExact(temporal.get(WEEK_BASED_YEAR), amount));
720                 case QUARTER_YEARS:
721                     return (R) temporal.plus(amount / 4, YEARS)
722                             .plus((amount % 4) * 3, MONTHS);
723                 default:
724                     throw new IllegalStateException("Unreachable");
725             }
726         }
727 
728         @Override
between(Temporal temporal1Inclusive, Temporal temporal2Exclusive)729         public long between(Temporal temporal1Inclusive, Temporal temporal2Exclusive) {
730             if (temporal1Inclusive.getClass() != temporal2Exclusive.getClass()) {
731                 return temporal1Inclusive.until(temporal2Exclusive, this);
732             }
733             switch(this) {
734                 case WEEK_BASED_YEARS:
735                     return Math.subtractExact(temporal2Exclusive.getLong(WEEK_BASED_YEAR),
736                             temporal1Inclusive.getLong(WEEK_BASED_YEAR));
737                 case QUARTER_YEARS:
738                     return temporal1Inclusive.until(temporal2Exclusive, MONTHS) / 3;
739                 default:
740                     throw new IllegalStateException("Unreachable");
741             }
742         }
743 
744         @Override
toString()745         public String toString() {
746             return name;
747         }
748     }
749 
isIso(TemporalAccessor temporal)750     static boolean isIso(TemporalAccessor temporal) {
751         return Chronology.from(temporal).equals(IsoChronology.INSTANCE);
752     }
753 }
754