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25 
26 package java.util;
27 
28 import java.io.IOException;
29 import java.io.ObjectInputStream;
30 import sun.util.locale.provider.CalendarDataUtility;
31 import sun.util.calendar.BaseCalendar;
32 import sun.util.calendar.CalendarDate;
33 import sun.util.calendar.CalendarSystem;
34 import sun.util.calendar.CalendarUtils;
35 import sun.util.calendar.Era;
36 import sun.util.calendar.Gregorian;
37 import sun.util.calendar.LocalGregorianCalendar;
38 import sun.util.calendar.ZoneInfo;
39 
40 /**
41  * {@code JapaneseImperialCalendar} implements a Japanese
42  * calendar system in which the imperial era-based year numbering is
43  * supported from the Meiji era. The following are the eras supported
44  * by this calendar system.
45  * <pre>{@code
46  * ERA value   Era name    Since (in Gregorian)
47  * ------------------------------------------------------
48  *     0       N/A         N/A
49  *     1       Meiji       1868-01-01T00:00:00 local time
50  *     2       Taisho      1912-07-30T00:00:00 local time
51  *     3       Showa       1926-12-25T00:00:00 local time
52  *     4       Heisei      1989-01-08T00:00:00 local time
53  *     5       Reiwa       2019-05-01T00:00:00 local time
54  * ------------------------------------------------------
55  * }</pre>
56  *
57  * <p><code>ERA</code> value 0 specifies the years before Meiji and
58  * the Gregorian year values are used. Unlike {@link
59  * GregorianCalendar}, the Julian to Gregorian transition is not
60  * supported because it doesn't make any sense to the Japanese
61  * calendar systems used before Meiji. To represent the years before
62  * Gregorian year 1, 0 and negative values are used. The Japanese
63  * Imperial rescripts and government decrees don't specify how to deal
64  * with time differences for applying the era transitions. This
65  * calendar implementation assumes local time for all transitions.
66  *
67  * @author Masayoshi Okutsu
68  * @since 1.6
69  */
70 class JapaneseImperialCalendar extends Calendar {
71     /*
72      * Implementation Notes
73      *
74      * This implementation uses
75      * sun.util.calendar.LocalGregorianCalendar to perform most of the
76      * calendar calculations. LocalGregorianCalendar is configurable
77      * and reads <JRE_HOME>/lib/calendars.properties at the start-up.
78      */
79 
80     /**
81      * The ERA constant designating the era before Meiji.
82      */
83     public static final int BEFORE_MEIJI = 0;
84 
85     /**
86      * The ERA constant designating the Meiji era.
87      */
88     public static final int MEIJI = 1;
89 
90     /**
91      * The ERA constant designating the Taisho era.
92      */
93     public static final int TAISHO = 2;
94 
95     /**
96      * The ERA constant designating the Showa era.
97      */
98     public static final int SHOWA = 3;
99 
100     /**
101      * The ERA constant designating the Heisei era.
102      */
103     public static final int HEISEI = 4;
104 
105     /**
106      * The ERA constant designating the Reiwa era.
107      */
108     private static final int REIWA = 5;
109 
110     private static final int EPOCH_OFFSET   = 719163; // Fixed date of January 1, 1970 (Gregorian)
111 
112     // Useful millisecond constants.  Although ONE_DAY and ONE_WEEK can fit
113     // into ints, they must be longs in order to prevent arithmetic overflow
114     // when performing (bug 4173516).
115     private static final int  ONE_SECOND = 1000;
116     private static final int  ONE_MINUTE = 60*ONE_SECOND;
117     private static final int  ONE_HOUR   = 60*ONE_MINUTE;
118     private static final long ONE_DAY    = 24*ONE_HOUR;
119     private static final long ONE_WEEK   = 7*ONE_DAY;
120 
121     // Reference to the sun.util.calendar.LocalGregorianCalendar instance (singleton).
122     private static final LocalGregorianCalendar jcal
123         = (LocalGregorianCalendar) CalendarSystem.forName("japanese");
124 
125     // Gregorian calendar instance. This is required because era
126     // transition dates are given in Gregorian dates.
127     private static final Gregorian gcal = CalendarSystem.getGregorianCalendar();
128 
129     // The Era instance representing "before Meiji".
130     private static final Era BEFORE_MEIJI_ERA = new Era("BeforeMeiji", "BM", Long.MIN_VALUE, false);
131 
132     // Imperial eras. The sun.util.calendar.LocalGregorianCalendar
133     // doesn't have an Era representing before Meiji, which is
134     // inconvenient for a Calendar. So, era[0] is a reference to
135     // BEFORE_MEIJI_ERA.
136     private static final Era[] eras;
137 
138     // Fixed date of the first date of each era.
139     private static final long[] sinceFixedDates;
140 
141     // The current era
142     private static final int currentEra;
143 
144     /*
145      * <pre>
146      *                                 Greatest       Least
147      * Field name             Minimum   Minimum     Maximum     Maximum
148      * ----------             -------   -------     -------     -------
149      * ERA                          0         0           1           1
150      * YEAR                -292275055         1           ?           ?
151      * MONTH                        0         0          11          11
152      * WEEK_OF_YEAR                 1         1          52*         53
153      * WEEK_OF_MONTH                0         0           4*          6
154      * DAY_OF_MONTH                 1         1          28*         31
155      * DAY_OF_YEAR                  1         1         365*        366
156      * DAY_OF_WEEK                  1         1           7           7
157      * DAY_OF_WEEK_IN_MONTH        -1        -1           4*          6
158      * AM_PM                        0         0           1           1
159      * HOUR                         0         0          11          11
160      * HOUR_OF_DAY                  0         0          23          23
161      * MINUTE                       0         0          59          59
162      * SECOND                       0         0          59          59
163      * MILLISECOND                  0         0         999         999
164      * ZONE_OFFSET             -13:00    -13:00       14:00       14:00
165      * DST_OFFSET                0:00      0:00        0:20        2:00
166      * </pre>
167      * *: depends on eras
168      */
169     static final int MIN_VALUES[] = {
170         0,              // ERA
171         -292275055,     // YEAR
172         JANUARY,        // MONTH
173         1,              // WEEK_OF_YEAR
174         0,              // WEEK_OF_MONTH
175         1,              // DAY_OF_MONTH
176         1,              // DAY_OF_YEAR
177         SUNDAY,         // DAY_OF_WEEK
178         1,              // DAY_OF_WEEK_IN_MONTH
179         AM,             // AM_PM
180         0,              // HOUR
181         0,              // HOUR_OF_DAY
182         0,              // MINUTE
183         0,              // SECOND
184         0,              // MILLISECOND
185         -13*ONE_HOUR,   // ZONE_OFFSET (UNIX compatibility)
186         0               // DST_OFFSET
187     };
188     static final int LEAST_MAX_VALUES[] = {
189         0,              // ERA (initialized later)
190         0,              // YEAR (initialized later)
191         JANUARY,        // MONTH (Showa 64 ended in January.)
192         0,              // WEEK_OF_YEAR (Showa 1 has only 6 days which could be 0 weeks.)
193         4,              // WEEK_OF_MONTH
194         28,             // DAY_OF_MONTH
195         0,              // DAY_OF_YEAR (initialized later)
196         SATURDAY,       // DAY_OF_WEEK
197         4,              // DAY_OF_WEEK_IN
198         PM,             // AM_PM
199         11,             // HOUR
200         23,             // HOUR_OF_DAY
201         59,             // MINUTE
202         59,             // SECOND
203         999,            // MILLISECOND
204         14*ONE_HOUR,    // ZONE_OFFSET
205         20*ONE_MINUTE   // DST_OFFSET (historical least maximum)
206     };
207     static final int MAX_VALUES[] = {
208         0,              // ERA
209         292278994,      // YEAR
210         DECEMBER,       // MONTH
211         53,             // WEEK_OF_YEAR
212         6,              // WEEK_OF_MONTH
213         31,             // DAY_OF_MONTH
214         366,            // DAY_OF_YEAR
215         SATURDAY,       // DAY_OF_WEEK
216         6,              // DAY_OF_WEEK_IN
217         PM,             // AM_PM
218         11,             // HOUR
219         23,             // HOUR_OF_DAY
220         59,             // MINUTE
221         59,             // SECOND
222         999,            // MILLISECOND
223         14*ONE_HOUR,    // ZONE_OFFSET
224         2*ONE_HOUR      // DST_OFFSET (double summer time)
225     };
226 
227     // Proclaim serialization compatibility with JDK 1.6
228     private static final long serialVersionUID = -3364572813905467929L;
229 
230     static {
231         Era[] es = jcal.getEras();
232         int length = es.length + 1;
233         eras = new Era[length];
234         sinceFixedDates = new long[length];
235 
236         // eras[BEFORE_MEIJI] and sinceFixedDate[BEFORE_MEIJI] are the
237         // same as Gregorian.
238         int index = BEFORE_MEIJI;
239         int current = index;
240         sinceFixedDates[index] = gcal.getFixedDate(BEFORE_MEIJI_ERA.getSinceDate());
241         eras[index++] = BEFORE_MEIJI_ERA;
242         for (Era e : es) {
243             if(e.getSince(TimeZone.NO_TIMEZONE) < System.currentTimeMillis()) {
244                 current = index;
245             }
246             CalendarDate d = e.getSinceDate();
247             sinceFixedDates[index] = gcal.getFixedDate(d);
248             eras[index++] = e;
249         }
250         currentEra = current;
251 
252         LEAST_MAX_VALUES[ERA] = MAX_VALUES[ERA] = eras.length - 1;
253 
254         // Calculate the least maximum year and least day of Year
255         // values. The following code assumes that there's at most one
256         // era transition in a Gregorian year.
257         int year = Integer.MAX_VALUE;
258         int dayOfYear = Integer.MAX_VALUE;
259         CalendarDate date = gcal.newCalendarDate(TimeZone.NO_TIMEZONE);
260         for (int i = 1; i < eras.length; i++) {
261             long fd = sinceFixedDates[i];
262             CalendarDate transitionDate = eras[i].getSinceDate();
transitionDate.getYear()263             date.setDate(transitionDate.getYear(), BaseCalendar.JANUARY, 1);
264             long fdd = gcal.getFixedDate(date);
265             if (fd != fdd) {
266                 dayOfYear = Math.min((int)(fd - fdd) + 1, dayOfYear);
267             }
transitionDate.getYear()268             date.setDate(transitionDate.getYear(), BaseCalendar.DECEMBER, 31);
269             fdd = gcal.getFixedDate(date);
270             if (fd != fdd) {
271                 dayOfYear = Math.min((int)(fdd - fd) + 1, dayOfYear);
272             }
273             LocalGregorianCalendar.Date lgd = getCalendarDate(fd - 1);
274             int y = lgd.getYear();
275             // Unless the first year starts from January 1, the actual
276             // max value could be one year short. For example, if it's
277             // Showa 63 January 8, 63 is the actual max value since
278             // Showa 64 January 8 doesn't exist.
279             if (!(lgd.getMonth() == BaseCalendar.JANUARY && lgd.getDayOfMonth() == 1)) {
280                 y--;
281             }
282             year = Math.min(y, year);
283         }
284         LEAST_MAX_VALUES[YEAR] = year; // Max year could be smaller than this value.
285         LEAST_MAX_VALUES[DAY_OF_YEAR] = dayOfYear;
286     }
287 
288     /**
289      * jdate always has a sun.util.calendar.LocalGregorianCalendar.Date instance to
290      * avoid overhead of creating it for each calculation.
291      */
292     private transient LocalGregorianCalendar.Date jdate;
293 
294     /**
295      * Temporary int[2] to get time zone offsets. zoneOffsets[0] gets
296      * the GMT offset value and zoneOffsets[1] gets the daylight saving
297      * value.
298      */
299     private transient int[] zoneOffsets;
300 
301     /**
302      * Temporary storage for saving original fields[] values in
303      * non-lenient mode.
304      */
305     private transient int[] originalFields;
306 
307     /**
308      * Constructs a <code>JapaneseImperialCalendar</code> based on the current time
309      * in the given time zone with the given locale.
310      *
311      * @param zone the given time zone.
312      * @param aLocale the given locale.
313      */
JapaneseImperialCalendar(TimeZone zone, Locale aLocale)314     JapaneseImperialCalendar(TimeZone zone, Locale aLocale) {
315         super(zone, aLocale);
316         jdate = jcal.newCalendarDate(zone);
317         setTimeInMillis(System.currentTimeMillis());
318     }
319 
320     /**
321      * Constructs an "empty" {@code JapaneseImperialCalendar}.
322      *
323      * @param zone    the given time zone
324      * @param aLocale the given locale
325      * @param flag    the flag requesting an empty instance
326      */
JapaneseImperialCalendar(TimeZone zone, Locale aLocale, boolean flag)327     JapaneseImperialCalendar(TimeZone zone, Locale aLocale, boolean flag) {
328         super(zone, aLocale);
329         jdate = jcal.newCalendarDate(zone);
330     }
331 
332     /**
333      * Returns {@code "japanese"} as the calendar type of this {@code
334      * JapaneseImperialCalendar}.
335      *
336      * @return {@code "japanese"}
337      */
338     @Override
getCalendarType()339     public String getCalendarType() {
340         return "japanese";
341     }
342 
343     /**
344      * Compares this <code>JapaneseImperialCalendar</code> to the specified
345      * <code>Object</code>. The result is <code>true</code> if and
346      * only if the argument is a <code>JapaneseImperialCalendar</code> object
347      * that represents the same time value (millisecond offset from
348      * the <a href="Calendar.html#Epoch">Epoch</a>) under the same
349      * <code>Calendar</code> parameters.
350      *
351      * @param obj the object to compare with.
352      * @return <code>true</code> if this object is equal to <code>obj</code>;
353      * <code>false</code> otherwise.
354      * @see Calendar#compareTo(Calendar)
355      */
356     @Override
equals(Object obj)357     public boolean equals(Object obj) {
358         return obj instanceof JapaneseImperialCalendar &&
359             super.equals(obj);
360     }
361 
362     /**
363      * Generates the hash code for this
364      * <code>JapaneseImperialCalendar</code> object.
365      */
366     @Override
hashCode()367     public int hashCode() {
368         return super.hashCode() ^ jdate.hashCode();
369     }
370 
371     /**
372      * Adds the specified (signed) amount of time to the given calendar field,
373      * based on the calendar's rules.
374      *
375      * <p><em>Add rule 1</em>. The value of <code>field</code>
376      * after the call minus the value of <code>field</code> before the
377      * call is <code>amount</code>, modulo any overflow that has occurred in
378      * <code>field</code>. Overflow occurs when a field value exceeds its
379      * range and, as a result, the next larger field is incremented or
380      * decremented and the field value is adjusted back into its range.</p>
381      *
382      * <p><em>Add rule 2</em>. If a smaller field is expected to be
383      * invariant, but it is impossible for it to be equal to its
384      * prior value because of changes in its minimum or maximum after
385      * <code>field</code> is changed, then its value is adjusted to be as close
386      * as possible to its expected value. A smaller field represents a
387      * smaller unit of time. <code>HOUR</code> is a smaller field than
388      * <code>DAY_OF_MONTH</code>. No adjustment is made to smaller fields
389      * that are not expected to be invariant. The calendar system
390      * determines what fields are expected to be invariant.</p>
391      *
392      * @param field the calendar field.
393      * @param amount the amount of date or time to be added to the field.
394      * @exception IllegalArgumentException if <code>field</code> is
395      * <code>ZONE_OFFSET</code>, <code>DST_OFFSET</code>, or unknown,
396      * or if any calendar fields have out-of-range values in
397      * non-lenient mode.
398      */
399     @Override
add(int field, int amount)400     public void add(int field, int amount) {
401         // If amount == 0, do nothing even the given field is out of
402         // range. This is tested by JCK.
403         if (amount == 0) {
404             return;   // Do nothing!
405         }
406 
407         if (field < 0 || field >= ZONE_OFFSET) {
408             throw new IllegalArgumentException();
409         }
410 
411         // Sync the time and calendar fields.
412         complete();
413 
414         if (field == YEAR) {
415             LocalGregorianCalendar.Date d = (LocalGregorianCalendar.Date) jdate.clone();
416             d.addYear(amount);
417             pinDayOfMonth(d);
418             set(ERA, getEraIndex(d));
419             set(YEAR, d.getYear());
420             set(MONTH, d.getMonth() - 1);
421             set(DAY_OF_MONTH, d.getDayOfMonth());
422         } else if (field == MONTH) {
423             LocalGregorianCalendar.Date d = (LocalGregorianCalendar.Date) jdate.clone();
424             d.addMonth(amount);
425             pinDayOfMonth(d);
426             set(ERA, getEraIndex(d));
427             set(YEAR, d.getYear());
428             set(MONTH, d.getMonth() - 1);
429             set(DAY_OF_MONTH, d.getDayOfMonth());
430         } else if (field == ERA) {
431             int era = internalGet(ERA) + amount;
432             if (era < 0) {
433                 era = 0;
434             } else if (era > eras.length - 1) {
435                 era = eras.length - 1;
436             }
437             set(ERA, era);
438         } else {
439             long delta = amount;
440             long timeOfDay = 0;
441             switch (field) {
442             // Handle the time fields here. Convert the given
443             // amount to milliseconds and call setTimeInMillis.
444             case HOUR:
445             case HOUR_OF_DAY:
446                 delta *= 60 * 60 * 1000;        // hours to milliseconds
447                 break;
448 
449             case MINUTE:
450                 delta *= 60 * 1000;             // minutes to milliseconds
451                 break;
452 
453             case SECOND:
454                 delta *= 1000;                  // seconds to milliseconds
455                 break;
456 
457             case MILLISECOND:
458                 break;
459 
460             // Handle week, day and AM_PM fields which involves
461             // time zone offset change adjustment. Convert the
462             // given amount to the number of days.
463             case WEEK_OF_YEAR:
464             case WEEK_OF_MONTH:
465             case DAY_OF_WEEK_IN_MONTH:
466                 delta *= 7;
467                 break;
468 
469             case DAY_OF_MONTH: // synonym of DATE
470             case DAY_OF_YEAR:
471             case DAY_OF_WEEK:
472                 break;
473 
474             case AM_PM:
475                 // Convert the amount to the number of days (delta)
476                 // and +12 or -12 hours (timeOfDay).
477                 delta = amount / 2;
478                 timeOfDay = 12 * (amount % 2);
479                 break;
480             }
481 
482             // The time fields don't require time zone offset change
483             // adjustment.
484             if (field >= HOUR) {
485                 setTimeInMillis(time + delta);
486                 return;
487             }
488 
489             // The rest of the fields (week, day or AM_PM fields)
490             // require time zone offset (both GMT and DST) change
491             // adjustment.
492 
493             // Translate the current time to the fixed date and time
494             // of the day.
495             long fd = cachedFixedDate;
496             timeOfDay += internalGet(HOUR_OF_DAY);
497             timeOfDay *= 60;
498             timeOfDay += internalGet(MINUTE);
499             timeOfDay *= 60;
500             timeOfDay += internalGet(SECOND);
501             timeOfDay *= 1000;
502             timeOfDay += internalGet(MILLISECOND);
503             if (timeOfDay >= ONE_DAY) {
504                 fd++;
505                 timeOfDay -= ONE_DAY;
506             } else if (timeOfDay < 0) {
507                 fd--;
508                 timeOfDay += ONE_DAY;
509             }
510 
511             fd += delta; // fd is the expected fixed date after the calculation
512             int zoneOffset = internalGet(ZONE_OFFSET) + internalGet(DST_OFFSET);
513             setTimeInMillis((fd - EPOCH_OFFSET) * ONE_DAY + timeOfDay - zoneOffset);
514             zoneOffset -= internalGet(ZONE_OFFSET) + internalGet(DST_OFFSET);
515             // If the time zone offset has changed, then adjust the difference.
516             if (zoneOffset != 0) {
517                 setTimeInMillis(time + zoneOffset);
518                 long fd2 = cachedFixedDate;
519                 // If the adjustment has changed the date, then take
520                 // the previous one.
521                 if (fd2 != fd) {
522                     setTimeInMillis(time - zoneOffset);
523                 }
524             }
525         }
526     }
527 
528     @Override
roll(int field, boolean up)529     public void roll(int field, boolean up) {
530         roll(field, up ? +1 : -1);
531     }
532 
533     /**
534      * Adds a signed amount to the specified calendar field without changing larger fields.
535      * A negative roll amount means to subtract from field without changing
536      * larger fields. If the specified amount is 0, this method performs nothing.
537      *
538      * <p>This method calls {@link #complete()} before adding the
539      * amount so that all the calendar fields are normalized. If there
540      * is any calendar field having an out-of-range value in non-lenient mode, then an
541      * <code>IllegalArgumentException</code> is thrown.
542      *
543      * @param field the calendar field.
544      * @param amount the signed amount to add to <code>field</code>.
545      * @exception IllegalArgumentException if <code>field</code> is
546      * <code>ZONE_OFFSET</code>, <code>DST_OFFSET</code>, or unknown,
547      * or if any calendar fields have out-of-range values in
548      * non-lenient mode.
549      * @see #roll(int,boolean)
550      * @see #add(int,int)
551      * @see #set(int,int)
552      */
553     @Override
roll(int field, int amount)554     public void roll(int field, int amount) {
555         // If amount == 0, do nothing even the given field is out of
556         // range. This is tested by JCK.
557         if (amount == 0) {
558             return;
559         }
560 
561         if (field < 0 || field >= ZONE_OFFSET) {
562             throw new IllegalArgumentException();
563         }
564 
565         // Sync the time and calendar fields.
566         complete();
567 
568         int min = getMinimum(field);
569         int max = getMaximum(field);
570 
571         switch (field) {
572         case ERA:
573         case AM_PM:
574         case MINUTE:
575         case SECOND:
576         case MILLISECOND:
577             // These fields are handled simply, since they have fixed
578             // minima and maxima. Other fields are complicated, since
579             // the range within they must roll varies depending on the
580             // date, a time zone and the era transitions.
581             break;
582 
583         case HOUR:
584         case HOUR_OF_DAY:
585             {
586                 int unit = max + 1; // 12 or 24 hours
587                 int h = internalGet(field);
588                 int nh = (h + amount) % unit;
589                 if (nh < 0) {
590                     nh += unit;
591                 }
592                 time += ONE_HOUR * (nh - h);
593 
594                 // The day might have changed, which could happen if
595                 // the daylight saving time transition brings it to
596                 // the next day, although it's very unlikely. But we
597                 // have to make sure not to change the larger fields.
598                 CalendarDate d = jcal.getCalendarDate(time, getZone());
599                 if (internalGet(DAY_OF_MONTH) != d.getDayOfMonth()) {
600                     d.setEra(jdate.getEra());
601                     d.setDate(internalGet(YEAR),
602                               internalGet(MONTH) + 1,
603                               internalGet(DAY_OF_MONTH));
604                     if (field == HOUR) {
605                         assert (internalGet(AM_PM) == PM);
606                         d.addHours(+12); // restore PM
607                     }
608                     time = jcal.getTime(d);
609                 }
610                 int hourOfDay = d.getHours();
611                 internalSet(field, hourOfDay % unit);
612                 if (field == HOUR) {
613                     internalSet(HOUR_OF_DAY, hourOfDay);
614                 } else {
615                     internalSet(AM_PM, hourOfDay / 12);
616                     internalSet(HOUR, hourOfDay % 12);
617                 }
618 
619                 // Time zone offset and/or daylight saving might have changed.
620                 int zoneOffset = d.getZoneOffset();
621                 int saving = d.getDaylightSaving();
622                 internalSet(ZONE_OFFSET, zoneOffset - saving);
623                 internalSet(DST_OFFSET, saving);
624                 return;
625             }
626 
627         case YEAR:
628             min = getActualMinimum(field);
629             max = getActualMaximum(field);
630             break;
631 
632         case MONTH:
633             // Rolling the month involves both pinning the final value to [0, 11]
634             // and adjusting the DAY_OF_MONTH if necessary.  We only adjust the
635             // DAY_OF_MONTH if, after updating the MONTH field, it is illegal.
636             // E.g., <jan31>.roll(MONTH, 1) -> <feb28> or <feb29>.
637             {
638                 if (!isTransitionYear(jdate.getNormalizedYear())) {
639                     int year = jdate.getYear();
640                     if (year == getMaximum(YEAR)) {
641                         CalendarDate jd = jcal.getCalendarDate(time, getZone());
642                         CalendarDate d = jcal.getCalendarDate(Long.MAX_VALUE, getZone());
643                         max = d.getMonth() - 1;
644                         int n = getRolledValue(internalGet(field), amount, min, max);
645                         if (n == max) {
646                             // To avoid overflow, use an equivalent year.
647                             jd.addYear(-400);
648                             jd.setMonth(n + 1);
649                             if (jd.getDayOfMonth() > d.getDayOfMonth()) {
650                                 jd.setDayOfMonth(d.getDayOfMonth());
651                                 jcal.normalize(jd);
652                             }
653                             if (jd.getDayOfMonth() == d.getDayOfMonth()
654                                 && jd.getTimeOfDay() > d.getTimeOfDay()) {
655                                 jd.setMonth(n + 1);
656                                 jd.setDayOfMonth(d.getDayOfMonth() - 1);
657                                 jcal.normalize(jd);
658                                 // Month may have changed by the normalization.
659                                 n = jd.getMonth() - 1;
660                             }
661                             set(DAY_OF_MONTH, jd.getDayOfMonth());
662                         }
663                         set(MONTH, n);
664                     } else if (year == getMinimum(YEAR)) {
665                         CalendarDate jd = jcal.getCalendarDate(time, getZone());
666                         CalendarDate d = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
667                         min = d.getMonth() - 1;
668                         int n = getRolledValue(internalGet(field), amount, min, max);
669                         if (n == min) {
670                             // To avoid underflow, use an equivalent year.
671                             jd.addYear(+400);
672                             jd.setMonth(n + 1);
673                             if (jd.getDayOfMonth() < d.getDayOfMonth()) {
674                                 jd.setDayOfMonth(d.getDayOfMonth());
675                                 jcal.normalize(jd);
676                             }
677                             if (jd.getDayOfMonth() == d.getDayOfMonth()
678                                 && jd.getTimeOfDay() < d.getTimeOfDay()) {
679                                 jd.setMonth(n + 1);
680                                 jd.setDayOfMonth(d.getDayOfMonth() + 1);
681                                 jcal.normalize(jd);
682                                 // Month may have changed by the normalization.
683                                 n = jd.getMonth() - 1;
684                             }
685                             set(DAY_OF_MONTH, jd.getDayOfMonth());
686                         }
687                         set(MONTH, n);
688                     } else {
689                         int mon = (internalGet(MONTH) + amount) % 12;
690                         if (mon < 0) {
691                             mon += 12;
692                         }
693                         set(MONTH, mon);
694 
695                         // Keep the day of month in the range.  We
696                         // don't want to spill over into the next
697                         // month; e.g., we don't want jan31 + 1 mo ->
698                         // feb31 -> mar3.
699                         int monthLen = monthLength(mon);
700                         if (internalGet(DAY_OF_MONTH) > monthLen) {
701                             set(DAY_OF_MONTH, monthLen);
702                         }
703                     }
704                 } else {
705                     int eraIndex = getEraIndex(jdate);
706                     CalendarDate transition = null;
707                     if (jdate.getYear() == 1) {
708                         transition = eras[eraIndex].getSinceDate();
709                         min = transition.getMonth() - 1;
710                     } else {
711                         if (eraIndex < eras.length - 1) {
712                             transition = eras[eraIndex + 1].getSinceDate();
713                             if (transition.getYear() == jdate.getNormalizedYear()) {
714                                 max = transition.getMonth() - 1;
715                                 if (transition.getDayOfMonth() == 1) {
716                                     max--;
717                                 }
718                             }
719                         }
720                     }
721 
722                     if (min == max) {
723                         // The year has only one month. No need to
724                         // process further. (Showa Gan-nen (year 1)
725                         // and the last year have only one month.)
726                         return;
727                     }
728                     int n = getRolledValue(internalGet(field), amount, min, max);
729                     set(MONTH, n);
730                     if (n == min) {
731                         if (!(transition.getMonth() == BaseCalendar.JANUARY
732                               && transition.getDayOfMonth() == 1)) {
733                             if (jdate.getDayOfMonth() < transition.getDayOfMonth()) {
734                                 set(DAY_OF_MONTH, transition.getDayOfMonth());
735                             }
736                         }
737                     } else if (n == max && (transition.getMonth() - 1 == n)) {
738                         int dom = transition.getDayOfMonth();
739                         if (jdate.getDayOfMonth() >= dom) {
740                             set(DAY_OF_MONTH, dom - 1);
741                         }
742                     }
743                 }
744                 return;
745             }
746 
747         case WEEK_OF_YEAR:
748             {
749                 int y = jdate.getNormalizedYear();
750                 max = getActualMaximum(WEEK_OF_YEAR);
751                 set(DAY_OF_WEEK, internalGet(DAY_OF_WEEK)); // update stamp[field]
752                 int woy = internalGet(WEEK_OF_YEAR);
753                 int value = woy + amount;
754                 if (!isTransitionYear(jdate.getNormalizedYear())) {
755                     int year = jdate.getYear();
756                     if (year == getMaximum(YEAR)) {
757                         max = getActualMaximum(WEEK_OF_YEAR);
758                     } else if (year == getMinimum(YEAR)) {
759                         min = getActualMinimum(WEEK_OF_YEAR);
760                         max = getActualMaximum(WEEK_OF_YEAR);
761                         if (value > min && value < max) {
762                             set(WEEK_OF_YEAR, value);
763                             return;
764                         }
765 
766                     }
767                     // If the new value is in between min and max
768                     // (exclusive), then we can use the value.
769                     if (value > min && value < max) {
770                         set(WEEK_OF_YEAR, value);
771                         return;
772                     }
773                     long fd = cachedFixedDate;
774                     // Make sure that the min week has the current DAY_OF_WEEK
775                     long day1 = fd - (7 * (woy - min));
776                     if (year != getMinimum(YEAR)) {
777                         if (gcal.getYearFromFixedDate(day1) != y) {
778                             min++;
779                         }
780                     } else {
781                         CalendarDate d = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
782                         if (day1 < jcal.getFixedDate(d)) {
783                             min++;
784                         }
785                     }
786 
787                     // Make sure the same thing for the max week
788                     fd += 7 * (max - internalGet(WEEK_OF_YEAR));
789                     if (gcal.getYearFromFixedDate(fd) != y) {
790                         max--;
791                     }
792                     break;
793                 }
794 
795                 // Handle transition here.
796                 long fd = cachedFixedDate;
797                 long day1 = fd - (7 * (woy - min));
798                 // Make sure that the min week has the current DAY_OF_WEEK
799                 LocalGregorianCalendar.Date d = getCalendarDate(day1);
800                 if (!(d.getEra() == jdate.getEra() && d.getYear() == jdate.getYear())) {
801                     min++;
802                 }
803 
804                 // Make sure the same thing for the max week
805                 fd += 7 * (max - woy);
806                 jcal.getCalendarDateFromFixedDate(d, fd);
807                 if (!(d.getEra() == jdate.getEra() && d.getYear() == jdate.getYear())) {
808                     max--;
809                 }
810                 // value: the new WEEK_OF_YEAR which must be converted
811                 // to month and day of month.
812                 value = getRolledValue(woy, amount, min, max) - 1;
813                 d = getCalendarDate(day1 + value * 7);
814                 set(MONTH, d.getMonth() - 1);
815                 set(DAY_OF_MONTH, d.getDayOfMonth());
816                 return;
817             }
818 
819         case WEEK_OF_MONTH:
820             {
821                 boolean isTransitionYear = isTransitionYear(jdate.getNormalizedYear());
822                 // dow: relative day of week from the first day of week
823                 int dow = internalGet(DAY_OF_WEEK) - getFirstDayOfWeek();
824                 if (dow < 0) {
825                     dow += 7;
826                 }
827 
828                 long fd = cachedFixedDate;
829                 long month1;     // fixed date of the first day (usually 1) of the month
830                 int monthLength; // actual month length
831                 if (isTransitionYear) {
832                     month1 = getFixedDateMonth1(jdate, fd);
833                     monthLength = actualMonthLength();
834                 } else {
835                     month1 = fd - internalGet(DAY_OF_MONTH) + 1;
836                     monthLength = jcal.getMonthLength(jdate);
837                 }
838 
839                 // the first day of week of the month.
840                 long monthDay1st = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(month1 + 6,
841                                                                                      getFirstDayOfWeek());
842                 // if the week has enough days to form a week, the
843                 // week starts from the previous month.
844                 if ((int)(monthDay1st - month1) >= getMinimalDaysInFirstWeek()) {
845                     monthDay1st -= 7;
846                 }
847                 max = getActualMaximum(field);
848 
849                 // value: the new WEEK_OF_MONTH value
850                 int value = getRolledValue(internalGet(field), amount, 1, max) - 1;
851 
852                 // nfd: fixed date of the rolled date
853                 long nfd = monthDay1st + value * 7 + dow;
854 
855                 // Unlike WEEK_OF_YEAR, we need to change day of week if the
856                 // nfd is out of the month.
857                 if (nfd < month1) {
858                     nfd = month1;
859                 } else if (nfd >= (month1 + monthLength)) {
860                     nfd = month1 + monthLength - 1;
861                 }
862                 set(DAY_OF_MONTH, (int)(nfd - month1) + 1);
863                 return;
864             }
865 
866         case DAY_OF_MONTH:
867             {
868                 if (!isTransitionYear(jdate.getNormalizedYear())) {
869                     max = jcal.getMonthLength(jdate);
870                     break;
871                 }
872 
873                 // TODO: Need to change the spec to be usable DAY_OF_MONTH rolling...
874 
875                 // Transition handling. We can't change year and era
876                 // values here due to the Calendar roll spec!
877                 long month1 = getFixedDateMonth1(jdate, cachedFixedDate);
878 
879                 // It may not be a regular month. Convert the date and range to
880                 // the relative values, perform the roll, and
881                 // convert the result back to the rolled date.
882                 int value = getRolledValue((int)(cachedFixedDate - month1), amount,
883                                            0, actualMonthLength() - 1);
884                 LocalGregorianCalendar.Date d = getCalendarDate(month1 + value);
885                 assert getEraIndex(d) == internalGetEra()
886                     && d.getYear() == internalGet(YEAR) && d.getMonth()-1 == internalGet(MONTH);
887                 set(DAY_OF_MONTH, d.getDayOfMonth());
888                 return;
889             }
890 
891         case DAY_OF_YEAR:
892             {
893                 max = getActualMaximum(field);
894                 if (!isTransitionYear(jdate.getNormalizedYear())) {
895                     break;
896                 }
897 
898                 // Handle transition. We can't change year and era values
899                 // here due to the Calendar roll spec.
900                 int value = getRolledValue(internalGet(DAY_OF_YEAR), amount, min, max);
901                 long jan0 = cachedFixedDate - internalGet(DAY_OF_YEAR);
902                 LocalGregorianCalendar.Date d = getCalendarDate(jan0 + value);
903                 assert getEraIndex(d) == internalGetEra() && d.getYear() == internalGet(YEAR);
904                 set(MONTH, d.getMonth() - 1);
905                 set(DAY_OF_MONTH, d.getDayOfMonth());
906                 return;
907             }
908 
909         case DAY_OF_WEEK:
910             {
911                 int normalizedYear = jdate.getNormalizedYear();
912                 if (!isTransitionYear(normalizedYear) && !isTransitionYear(normalizedYear - 1)) {
913                     // If the week of year is in the same year, we can
914                     // just change DAY_OF_WEEK.
915                     int weekOfYear = internalGet(WEEK_OF_YEAR);
916                     if (weekOfYear > 1 && weekOfYear < 52) {
917                         set(WEEK_OF_YEAR, internalGet(WEEK_OF_YEAR));
918                         max = SATURDAY;
919                         break;
920                     }
921                 }
922 
923                 // We need to handle it in a different way around year
924                 // boundaries and in the transition year. Note that
925                 // changing era and year values violates the roll
926                 // rule: not changing larger calendar fields...
927                 amount %= 7;
928                 if (amount == 0) {
929                     return;
930                 }
931                 long fd = cachedFixedDate;
932                 long dowFirst = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(fd, getFirstDayOfWeek());
933                 fd += amount;
934                 if (fd < dowFirst) {
935                     fd += 7;
936                 } else if (fd >= dowFirst + 7) {
937                     fd -= 7;
938                 }
939                 LocalGregorianCalendar.Date d = getCalendarDate(fd);
940                 set(ERA, getEraIndex(d));
941                 set(d.getYear(), d.getMonth() - 1, d.getDayOfMonth());
942                 return;
943             }
944 
945         case DAY_OF_WEEK_IN_MONTH:
946             {
947                 min = 1; // after having normalized, min should be 1.
948                 if (!isTransitionYear(jdate.getNormalizedYear())) {
949                     int dom = internalGet(DAY_OF_MONTH);
950                     int monthLength = jcal.getMonthLength(jdate);
951                     int lastDays = monthLength % 7;
952                     max = monthLength / 7;
953                     int x = (dom - 1) % 7;
954                     if (x < lastDays) {
955                         max++;
956                     }
957                     set(DAY_OF_WEEK, internalGet(DAY_OF_WEEK));
958                     break;
959                 }
960 
961                 // Transition year handling.
962                 long fd = cachedFixedDate;
963                 long month1 = getFixedDateMonth1(jdate, fd);
964                 int monthLength = actualMonthLength();
965                 int lastDays = monthLength % 7;
966                 max = monthLength / 7;
967                 int x = (int)(fd - month1) % 7;
968                 if (x < lastDays) {
969                     max++;
970                 }
971                 int value = getRolledValue(internalGet(field), amount, min, max) - 1;
972                 fd = month1 + value * 7 + x;
973                 LocalGregorianCalendar.Date d = getCalendarDate(fd);
974                 set(DAY_OF_MONTH, d.getDayOfMonth());
975                 return;
976             }
977         }
978 
979         set(field, getRolledValue(internalGet(field), amount, min, max));
980     }
981 
982     @Override
getDisplayName(int field, int style, Locale locale)983     public String getDisplayName(int field, int style, Locale locale) {
984         if (!checkDisplayNameParams(field, style, SHORT, NARROW_FORMAT, locale,
985                                     ERA_MASK|YEAR_MASK|MONTH_MASK|DAY_OF_WEEK_MASK|AM_PM_MASK)) {
986             return null;
987         }
988 
989         int fieldValue = get(field);
990 
991         // "GanNen" is supported only in the LONG style.
992         if (field == YEAR
993             && (getBaseStyle(style) != LONG || fieldValue != 1 || get(ERA) == 0)) {
994             return null;
995         }
996 
997         String name = CalendarDataUtility.retrieveFieldValueName(getCalendarType(), field,
998                                                                  fieldValue, style, locale);
999         // If the ERA value is null or empty, then
1000         // try to get its name or abbreviation from the Era instance.
1001         if ((name == null || name.isEmpty()) &&
1002                 field == ERA &&
1003                 fieldValue < eras.length) {
1004             Era era = eras[fieldValue];
1005             name = (style == SHORT) ? era.getAbbreviation() : era.getName();
1006         }
1007         return name;
1008     }
1009 
1010     @Override
getDisplayNames(int field, int style, Locale locale)1011     public Map<String,Integer> getDisplayNames(int field, int style, Locale locale) {
1012         if (!checkDisplayNameParams(field, style, ALL_STYLES, NARROW_FORMAT, locale,
1013                                     ERA_MASK|YEAR_MASK|MONTH_MASK|DAY_OF_WEEK_MASK|AM_PM_MASK)) {
1014             return null;
1015         }
1016         Map<String, Integer> names;
1017         names = CalendarDataUtility.retrieveFieldValueNames(getCalendarType(), field, style, locale);
1018         // If strings[] has fewer than eras[], get more names from eras[].
1019         if (names != null) {
1020             if (field == ERA) {
1021                 int size = names.size();
1022                 if (style == ALL_STYLES) {
1023                     Set<Integer> values = new HashSet<>();
1024                     // count unique era values
1025                     for (String key : names.keySet()) {
1026                         values.add(names.get(key));
1027                     }
1028                     size = values.size();
1029                 }
1030                 if (size < eras.length) {
1031                     int baseStyle = getBaseStyle(style);
1032                     for (int i = size; i < eras.length; i++) {
1033                         Era era = eras[i];
1034                         if (baseStyle == ALL_STYLES || baseStyle == SHORT
1035                                 || baseStyle == NARROW_FORMAT) {
1036                             names.put(era.getAbbreviation(), i);
1037                         }
1038                         if (baseStyle == ALL_STYLES || baseStyle == LONG) {
1039                             names.put(era.getName(), i);
1040                         }
1041                     }
1042                 }
1043             }
1044         }
1045         return names;
1046     }
1047 
1048     /**
1049      * Returns the minimum value for the given calendar field of this
1050      * <code>Calendar</code> instance. The minimum value is
1051      * defined as the smallest value returned by the {@link
1052      * Calendar#get(int) get} method for any possible time value,
1053      * taking into consideration the current values of the
1054      * {@link Calendar#getFirstDayOfWeek() getFirstDayOfWeek},
1055      * {@link Calendar#getMinimalDaysInFirstWeek() getMinimalDaysInFirstWeek},
1056      * and {@link Calendar#getTimeZone() getTimeZone} methods.
1057      *
1058      * @param field the calendar field.
1059      * @return the minimum value for the given calendar field.
1060      * @see #getMaximum(int)
1061      * @see #getGreatestMinimum(int)
1062      * @see #getLeastMaximum(int)
1063      * @see #getActualMinimum(int)
1064      * @see #getActualMaximum(int)
1065      */
getMinimum(int field)1066     public int getMinimum(int field) {
1067         return MIN_VALUES[field];
1068     }
1069 
1070     /**
1071      * Returns the maximum value for the given calendar field of this
1072      * <code>GregorianCalendar</code> instance. The maximum value is
1073      * defined as the largest value returned by the {@link
1074      * Calendar#get(int) get} method for any possible time value,
1075      * taking into consideration the current values of the
1076      * {@link Calendar#getFirstDayOfWeek() getFirstDayOfWeek},
1077      * {@link Calendar#getMinimalDaysInFirstWeek() getMinimalDaysInFirstWeek},
1078      * and {@link Calendar#getTimeZone() getTimeZone} methods.
1079      *
1080      * @param field the calendar field.
1081      * @return the maximum value for the given calendar field.
1082      * @see #getMinimum(int)
1083      * @see #getGreatestMinimum(int)
1084      * @see #getLeastMaximum(int)
1085      * @see #getActualMinimum(int)
1086      * @see #getActualMaximum(int)
1087      */
getMaximum(int field)1088     public int getMaximum(int field) {
1089         switch (field) {
1090         case YEAR:
1091             {
1092                 // The value should depend on the time zone of this calendar.
1093                 LocalGregorianCalendar.Date d = jcal.getCalendarDate(Long.MAX_VALUE,
1094                                                                      getZone());
1095                 return Math.max(LEAST_MAX_VALUES[YEAR], d.getYear());
1096             }
1097         }
1098         return MAX_VALUES[field];
1099     }
1100 
1101     /**
1102      * Returns the highest minimum value for the given calendar field
1103      * of this <code>GregorianCalendar</code> instance. The highest
1104      * minimum value is defined as the largest value returned by
1105      * {@link #getActualMinimum(int)} for any possible time value,
1106      * taking into consideration the current values of the
1107      * {@link Calendar#getFirstDayOfWeek() getFirstDayOfWeek},
1108      * {@link Calendar#getMinimalDaysInFirstWeek() getMinimalDaysInFirstWeek},
1109      * and {@link Calendar#getTimeZone() getTimeZone} methods.
1110      *
1111      * @param field the calendar field.
1112      * @return the highest minimum value for the given calendar field.
1113      * @see #getMinimum(int)
1114      * @see #getMaximum(int)
1115      * @see #getLeastMaximum(int)
1116      * @see #getActualMinimum(int)
1117      * @see #getActualMaximum(int)
1118      */
getGreatestMinimum(int field)1119     public int getGreatestMinimum(int field) {
1120         return field == YEAR ? 1 : MIN_VALUES[field];
1121     }
1122 
1123     /**
1124      * Returns the lowest maximum value for the given calendar field
1125      * of this <code>GregorianCalendar</code> instance. The lowest
1126      * maximum value is defined as the smallest value returned by
1127      * {@link #getActualMaximum(int)} for any possible time value,
1128      * taking into consideration the current values of the
1129      * {@link Calendar#getFirstDayOfWeek() getFirstDayOfWeek},
1130      * {@link Calendar#getMinimalDaysInFirstWeek() getMinimalDaysInFirstWeek},
1131      * and {@link Calendar#getTimeZone() getTimeZone} methods.
1132      *
1133      * @param field the calendar field
1134      * @return the lowest maximum value for the given calendar field.
1135      * @see #getMinimum(int)
1136      * @see #getMaximum(int)
1137      * @see #getGreatestMinimum(int)
1138      * @see #getActualMinimum(int)
1139      * @see #getActualMaximum(int)
1140      */
getLeastMaximum(int field)1141     public int getLeastMaximum(int field) {
1142         switch (field) {
1143         case YEAR:
1144             {
1145                 return Math.min(LEAST_MAX_VALUES[YEAR], getMaximum(YEAR));
1146             }
1147         }
1148         return LEAST_MAX_VALUES[field];
1149     }
1150 
1151     /**
1152      * Returns the minimum value that this calendar field could have,
1153      * taking into consideration the given time value and the current
1154      * values of the
1155      * {@link Calendar#getFirstDayOfWeek() getFirstDayOfWeek},
1156      * {@link Calendar#getMinimalDaysInFirstWeek() getMinimalDaysInFirstWeek},
1157      * and {@link Calendar#getTimeZone() getTimeZone} methods.
1158      *
1159      * @param field the calendar field
1160      * @return the minimum of the given field for the time value of
1161      * this <code>JapaneseImperialCalendar</code>
1162      * @see #getMinimum(int)
1163      * @see #getMaximum(int)
1164      * @see #getGreatestMinimum(int)
1165      * @see #getLeastMaximum(int)
1166      * @see #getActualMaximum(int)
1167      */
getActualMinimum(int field)1168     public int getActualMinimum(int field) {
1169         if (!isFieldSet(YEAR_MASK|MONTH_MASK|WEEK_OF_YEAR_MASK, field)) {
1170             return getMinimum(field);
1171         }
1172 
1173         int value = 0;
1174         JapaneseImperialCalendar jc = getNormalizedCalendar();
1175         // Get a local date which includes time of day and time zone,
1176         // which are missing in jc.jdate.
1177         LocalGregorianCalendar.Date jd = jcal.getCalendarDate(jc.getTimeInMillis(),
1178                                                               getZone());
1179         int eraIndex = getEraIndex(jd);
1180         switch (field) {
1181         case YEAR:
1182             {
1183                 if (eraIndex > BEFORE_MEIJI) {
1184                     value = 1;
1185                     long since = eras[eraIndex].getSince(getZone());
1186                     CalendarDate d = jcal.getCalendarDate(since, getZone());
1187                     // Use the same year in jd to take care of leap
1188                     // years. i.e., both jd and d must agree on leap
1189                     // or common years.
1190                     jd.setYear(d.getYear());
1191                     jcal.normalize(jd);
1192                     assert jd.isLeapYear() == d.isLeapYear();
1193                     if (getYearOffsetInMillis(jd) < getYearOffsetInMillis(d)) {
1194                         value++;
1195                     }
1196                 } else {
1197                     value = getMinimum(field);
1198                     CalendarDate d = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
1199                     // Use an equvalent year of d.getYear() if
1200                     // possible. Otherwise, ignore the leap year and
1201                     // common year difference.
1202                     int y = d.getYear();
1203                     if (y > 400) {
1204                         y -= 400;
1205                     }
1206                     jd.setYear(y);
1207                     jcal.normalize(jd);
1208                     if (getYearOffsetInMillis(jd) < getYearOffsetInMillis(d)) {
1209                         value++;
1210                     }
1211                 }
1212             }
1213             break;
1214 
1215         case MONTH:
1216             {
1217                 // In Before Meiji and Meiji, January is the first month.
1218                 if (eraIndex > MEIJI && jd.getYear() == 1) {
1219                     long since = eras[eraIndex].getSince(getZone());
1220                     CalendarDate d = jcal.getCalendarDate(since, getZone());
1221                     value = d.getMonth() - 1;
1222                     if (jd.getDayOfMonth() < d.getDayOfMonth()) {
1223                         value++;
1224                     }
1225                 }
1226             }
1227             break;
1228 
1229         case WEEK_OF_YEAR:
1230             {
1231                 value = 1;
1232                 CalendarDate d = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
1233                 // shift 400 years to avoid underflow
1234                 d.addYear(+400);
1235                 jcal.normalize(d);
1236                 jd.setEra(d.getEra());
1237                 jd.setYear(d.getYear());
1238                 jcal.normalize(jd);
1239 
1240                 long jan1 = jcal.getFixedDate(d);
1241                 long fd = jcal.getFixedDate(jd);
1242                 int woy = getWeekNumber(jan1, fd);
1243                 long day1 = fd - (7 * (woy - 1));
1244                 if ((day1 < jan1) ||
1245                     (day1 == jan1 &&
1246                      jd.getTimeOfDay() < d.getTimeOfDay())) {
1247                     value++;
1248                 }
1249             }
1250             break;
1251         }
1252         return value;
1253     }
1254 
1255     /**
1256      * Returns the maximum value that this calendar field could have,
1257      * taking into consideration the given time value and the current
1258      * values of the
1259      * {@link Calendar#getFirstDayOfWeek() getFirstDayOfWeek},
1260      * {@link Calendar#getMinimalDaysInFirstWeek() getMinimalDaysInFirstWeek},
1261      * and
1262      * {@link Calendar#getTimeZone() getTimeZone} methods.
1263      * For example, if the date of this instance is Heisei 16February 1,
1264      * the actual maximum value of the <code>DAY_OF_MONTH</code> field
1265      * is 29 because Heisei 16 is a leap year, and if the date of this
1266      * instance is Heisei 17 February 1, it's 28.
1267      *
1268      * @param field the calendar field
1269      * @return the maximum of the given field for the time value of
1270      * this <code>JapaneseImperialCalendar</code>
1271      * @see #getMinimum(int)
1272      * @see #getMaximum(int)
1273      * @see #getGreatestMinimum(int)
1274      * @see #getLeastMaximum(int)
1275      * @see #getActualMinimum(int)
1276      */
getActualMaximum(int field)1277     public int getActualMaximum(int field) {
1278         final int fieldsForFixedMax = ERA_MASK|DAY_OF_WEEK_MASK|HOUR_MASK|AM_PM_MASK|
1279             HOUR_OF_DAY_MASK|MINUTE_MASK|SECOND_MASK|MILLISECOND_MASK|
1280             ZONE_OFFSET_MASK|DST_OFFSET_MASK;
1281         if ((fieldsForFixedMax & (1<<field)) != 0) {
1282             return getMaximum(field);
1283         }
1284 
1285         JapaneseImperialCalendar jc = getNormalizedCalendar();
1286         LocalGregorianCalendar.Date date = jc.jdate;
1287         int normalizedYear = date.getNormalizedYear();
1288 
1289         int value = -1;
1290         switch (field) {
1291         case MONTH:
1292             {
1293                 value = DECEMBER;
1294                 if (isTransitionYear(date.getNormalizedYear())) {
1295                     // TODO: there may be multiple transitions in a year.
1296                     int eraIndex = getEraIndex(date);
1297                     if (date.getYear() != 1) {
1298                         eraIndex++;
1299                         assert eraIndex < eras.length;
1300                     }
1301                     long transition = sinceFixedDates[eraIndex];
1302                     long fd = jc.cachedFixedDate;
1303                     if (fd < transition) {
1304                         LocalGregorianCalendar.Date ldate
1305                             = (LocalGregorianCalendar.Date) date.clone();
1306                         jcal.getCalendarDateFromFixedDate(ldate, transition - 1);
1307                         value = ldate.getMonth() - 1;
1308                     }
1309                 } else {
1310                     LocalGregorianCalendar.Date d = jcal.getCalendarDate(Long.MAX_VALUE,
1311                                                                          getZone());
1312                     if (date.getEra() == d.getEra() && date.getYear() == d.getYear()) {
1313                         value = d.getMonth() - 1;
1314                     }
1315                 }
1316             }
1317             break;
1318 
1319         case DAY_OF_MONTH:
1320             value = jcal.getMonthLength(date);
1321             break;
1322 
1323         case DAY_OF_YEAR:
1324             {
1325                 if (isTransitionYear(date.getNormalizedYear())) {
1326                     // Handle transition year.
1327                     // TODO: there may be multiple transitions in a year.
1328                     int eraIndex = getEraIndex(date);
1329                     if (date.getYear() != 1) {
1330                         eraIndex++;
1331                         assert eraIndex < eras.length;
1332                     }
1333                     long transition = sinceFixedDates[eraIndex];
1334                     long fd = jc.cachedFixedDate;
1335                     CalendarDate d = gcal.newCalendarDate(TimeZone.NO_TIMEZONE);
1336                     d.setDate(date.getNormalizedYear(), BaseCalendar.JANUARY, 1);
1337                     if (fd < transition) {
1338                         value = (int)(transition - gcal.getFixedDate(d));
1339                     } else {
1340                         d.addYear(+1);
1341                         value = (int)(gcal.getFixedDate(d) - transition);
1342                     }
1343                 } else {
1344                     LocalGregorianCalendar.Date d = jcal.getCalendarDate(Long.MAX_VALUE,
1345                                                                          getZone());
1346                     if (date.getEra() == d.getEra() && date.getYear() == d.getYear()) {
1347                         long fd = jcal.getFixedDate(d);
1348                         long jan1 = getFixedDateJan1(d, fd);
1349                         value = (int)(fd - jan1) + 1;
1350                     } else if (date.getYear() == getMinimum(YEAR)) {
1351                         CalendarDate d1 = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
1352                         long fd1 = jcal.getFixedDate(d1);
1353                         d1.addYear(1);
1354                         d1.setMonth(BaseCalendar.JANUARY).setDayOfMonth(1);
1355                         jcal.normalize(d1);
1356                         long fd2 = jcal.getFixedDate(d1);
1357                         value = (int)(fd2 - fd1);
1358                     } else {
1359                         value = jcal.getYearLength(date);
1360                     }
1361                 }
1362             }
1363             break;
1364 
1365         case WEEK_OF_YEAR:
1366             {
1367                 if (!isTransitionYear(date.getNormalizedYear())) {
1368                     LocalGregorianCalendar.Date jd = jcal.getCalendarDate(Long.MAX_VALUE,
1369                                                                           getZone());
1370                     if (date.getEra() == jd.getEra() && date.getYear() == jd.getYear()) {
1371                         long fd = jcal.getFixedDate(jd);
1372                         long jan1 = getFixedDateJan1(jd, fd);
1373                         value = getWeekNumber(jan1, fd);
1374                     } else if (date.getEra() == null && date.getYear() == getMinimum(YEAR)) {
1375                         CalendarDate d = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
1376                         // shift 400 years to avoid underflow
1377                         d.addYear(+400);
1378                         jcal.normalize(d);
1379                         jd.setEra(d.getEra());
1380                         jd.setDate(d.getYear() + 1, BaseCalendar.JANUARY, 1);
1381                         jcal.normalize(jd);
1382                         long jan1 = jcal.getFixedDate(d);
1383                         long nextJan1 = jcal.getFixedDate(jd);
1384                         long nextJan1st = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(nextJan1 + 6,
1385                                                                                             getFirstDayOfWeek());
1386                         int ndays = (int)(nextJan1st - nextJan1);
1387                         if (ndays >= getMinimalDaysInFirstWeek()) {
1388                             nextJan1st -= 7;
1389                         }
1390                         value = getWeekNumber(jan1, nextJan1st);
1391                     } else {
1392                         // Get the day of week of January 1 of the year
1393                         CalendarDate d = gcal.newCalendarDate(TimeZone.NO_TIMEZONE);
1394                         d.setDate(date.getNormalizedYear(), BaseCalendar.JANUARY, 1);
1395                         int dayOfWeek = gcal.getDayOfWeek(d);
1396                         // Normalize the day of week with the firstDayOfWeek value
1397                         dayOfWeek -= getFirstDayOfWeek();
1398                         if (dayOfWeek < 0) {
1399                             dayOfWeek += 7;
1400                         }
1401                         value = 52;
1402                         int magic = dayOfWeek + getMinimalDaysInFirstWeek() - 1;
1403                         if ((magic == 6) ||
1404                             (date.isLeapYear() && (magic == 5 || magic == 12))) {
1405                             value++;
1406                         }
1407                     }
1408                     break;
1409                 }
1410 
1411                 if (jc == this) {
1412                     jc = (JapaneseImperialCalendar) jc.clone();
1413                 }
1414                 int max = getActualMaximum(DAY_OF_YEAR);
1415                 jc.set(DAY_OF_YEAR, max);
1416                 value = jc.get(WEEK_OF_YEAR);
1417                 if (value == 1 && max > 7) {
1418                     jc.add(WEEK_OF_YEAR, -1);
1419                     value = jc.get(WEEK_OF_YEAR);
1420                 }
1421             }
1422             break;
1423 
1424         case WEEK_OF_MONTH:
1425             {
1426                 LocalGregorianCalendar.Date jd = jcal.getCalendarDate(Long.MAX_VALUE,
1427                                                                       getZone());
1428                 if (!(date.getEra() == jd.getEra() && date.getYear() == jd.getYear())) {
1429                     CalendarDate d = gcal.newCalendarDate(TimeZone.NO_TIMEZONE);
1430                     d.setDate(date.getNormalizedYear(), date.getMonth(), 1);
1431                     int dayOfWeek = gcal.getDayOfWeek(d);
1432                     int monthLength = gcal.getMonthLength(d);
1433                     dayOfWeek -= getFirstDayOfWeek();
1434                     if (dayOfWeek < 0) {
1435                         dayOfWeek += 7;
1436                     }
1437                     int nDaysFirstWeek = 7 - dayOfWeek; // # of days in the first week
1438                     value = 3;
1439                     if (nDaysFirstWeek >= getMinimalDaysInFirstWeek()) {
1440                         value++;
1441                     }
1442                     monthLength -= nDaysFirstWeek + 7 * 3;
1443                     if (monthLength > 0) {
1444                         value++;
1445                         if (monthLength > 7) {
1446                             value++;
1447                         }
1448                     }
1449                 } else {
1450                     long fd = jcal.getFixedDate(jd);
1451                     long month1 = fd - jd.getDayOfMonth() + 1;
1452                     value = getWeekNumber(month1, fd);
1453                 }
1454             }
1455             break;
1456 
1457         case DAY_OF_WEEK_IN_MONTH:
1458             {
1459                 int ndays, dow1;
1460                 int dow = date.getDayOfWeek();
1461                 BaseCalendar.Date d = (BaseCalendar.Date) date.clone();
1462                 ndays = jcal.getMonthLength(d);
1463                 d.setDayOfMonth(1);
1464                 jcal.normalize(d);
1465                 dow1 = d.getDayOfWeek();
1466                 int x = dow - dow1;
1467                 if (x < 0) {
1468                     x += 7;
1469                 }
1470                 ndays -= x;
1471                 value = (ndays + 6) / 7;
1472             }
1473             break;
1474 
1475         case YEAR:
1476             {
1477                 CalendarDate jd = jcal.getCalendarDate(jc.getTimeInMillis(), getZone());
1478                 CalendarDate d;
1479                 int eraIndex = getEraIndex(date);
1480                 if (eraIndex == eras.length - 1) {
1481                     d = jcal.getCalendarDate(Long.MAX_VALUE, getZone());
1482                     value = d.getYear();
1483                     // Use an equivalent year for the
1484                     // getYearOffsetInMillis call to avoid overflow.
1485                     if (value > 400) {
1486                         jd.setYear(value - 400);
1487                     }
1488                 } else {
1489                     d = jcal.getCalendarDate(eras[eraIndex + 1].getSince(getZone()) - 1,
1490                                              getZone());
1491                     value = d.getYear();
1492                     // Use the same year as d.getYear() to be
1493                     // consistent with leap and common years.
1494                     jd.setYear(value);
1495                 }
1496                 jcal.normalize(jd);
1497                 if (getYearOffsetInMillis(jd) > getYearOffsetInMillis(d)) {
1498                     value--;
1499                 }
1500             }
1501             break;
1502 
1503         default:
1504             throw new ArrayIndexOutOfBoundsException(field);
1505         }
1506         return value;
1507     }
1508 
1509     /**
1510      * Returns the millisecond offset from the beginning of the
1511      * year. In the year for Long.MIN_VALUE, it's a pseudo value
1512      * beyond the limit. The given CalendarDate object must have been
1513      * normalized before calling this method.
1514      */
getYearOffsetInMillis(CalendarDate date)1515     private long getYearOffsetInMillis(CalendarDate date) {
1516         long t = (jcal.getDayOfYear(date) - 1) * ONE_DAY;
1517         return t + date.getTimeOfDay() - date.getZoneOffset();
1518     }
1519 
clone()1520     public Object clone() {
1521         JapaneseImperialCalendar other = (JapaneseImperialCalendar) super.clone();
1522 
1523         other.jdate = (LocalGregorianCalendar.Date) jdate.clone();
1524         other.originalFields = null;
1525         other.zoneOffsets = null;
1526         return other;
1527     }
1528 
getTimeZone()1529     public TimeZone getTimeZone() {
1530         TimeZone zone = super.getTimeZone();
1531         // To share the zone by the CalendarDate
1532         jdate.setZone(zone);
1533         return zone;
1534     }
1535 
setTimeZone(TimeZone zone)1536     public void setTimeZone(TimeZone zone) {
1537         super.setTimeZone(zone);
1538         // To share the zone by the CalendarDate
1539         jdate.setZone(zone);
1540     }
1541 
1542     /**
1543      * The fixed date corresponding to jdate. If the value is
1544      * Long.MIN_VALUE, the fixed date value is unknown.
1545      */
1546     transient private long cachedFixedDate = Long.MIN_VALUE;
1547 
1548     /**
1549      * Converts the time value (millisecond offset from the <a
1550      * href="Calendar.html#Epoch">Epoch</a>) to calendar field values.
1551      * The time is <em>not</em>
1552      * recomputed first; to recompute the time, then the fields, call the
1553      * <code>complete</code> method.
1554      *
1555      * @see Calendar#complete
1556      */
computeFields()1557     protected void computeFields() {
1558         int mask = 0;
1559         if (isPartiallyNormalized()) {
1560             // Determine which calendar fields need to be computed.
1561             mask = getSetStateFields();
1562             int fieldMask = ~mask & ALL_FIELDS;
1563             if (fieldMask != 0 || cachedFixedDate == Long.MIN_VALUE) {
1564                 mask |= computeFields(fieldMask,
1565                                       mask & (ZONE_OFFSET_MASK|DST_OFFSET_MASK));
1566                 assert mask == ALL_FIELDS;
1567             }
1568         } else {
1569             // Specify all fields
1570             mask = ALL_FIELDS;
1571             computeFields(mask, 0);
1572         }
1573         // After computing all the fields, set the field state to `COMPUTED'.
1574         setFieldsComputed(mask);
1575     }
1576 
1577     /**
1578      * This computeFields implements the conversion from UTC
1579      * (millisecond offset from the Epoch) to calendar
1580      * field values. fieldMask specifies which fields to change the
1581      * setting state to COMPUTED, although all fields are set to
1582      * the correct values. This is required to fix 4685354.
1583      *
1584      * @param fieldMask a bit mask to specify which fields to change
1585      * the setting state.
1586      * @param tzMask a bit mask to specify which time zone offset
1587      * fields to be used for time calculations
1588      * @return a new field mask that indicates what field values have
1589      * actually been set.
1590      */
computeFields(int fieldMask, int tzMask)1591     private int computeFields(int fieldMask, int tzMask) {
1592         int zoneOffset = 0;
1593         TimeZone tz = getZone();
1594         if (zoneOffsets == null) {
1595             zoneOffsets = new int[2];
1596         }
1597         if (tzMask != (ZONE_OFFSET_MASK|DST_OFFSET_MASK)) {
1598             if (tz instanceof ZoneInfo) {
1599                 zoneOffset = ((ZoneInfo)tz).getOffsets(time, zoneOffsets);
1600             } else {
1601                 zoneOffset = tz.getOffset(time);
1602                 zoneOffsets[0] = tz.getRawOffset();
1603                 zoneOffsets[1] = zoneOffset - zoneOffsets[0];
1604             }
1605         }
1606         if (tzMask != 0) {
1607             if (isFieldSet(tzMask, ZONE_OFFSET)) {
1608                 zoneOffsets[0] = internalGet(ZONE_OFFSET);
1609             }
1610             if (isFieldSet(tzMask, DST_OFFSET)) {
1611                 zoneOffsets[1] = internalGet(DST_OFFSET);
1612             }
1613             zoneOffset = zoneOffsets[0] + zoneOffsets[1];
1614         }
1615 
1616         // By computing time and zoneOffset separately, we can take
1617         // the wider range of time+zoneOffset than the previous
1618         // implementation.
1619         long fixedDate = zoneOffset / ONE_DAY;
1620         int timeOfDay = zoneOffset % (int)ONE_DAY;
1621         fixedDate += time / ONE_DAY;
1622         timeOfDay += (int) (time % ONE_DAY);
1623         if (timeOfDay >= ONE_DAY) {
1624             timeOfDay -= ONE_DAY;
1625             ++fixedDate;
1626         } else {
1627             while (timeOfDay < 0) {
1628                 timeOfDay += ONE_DAY;
1629                 --fixedDate;
1630             }
1631         }
1632         fixedDate += EPOCH_OFFSET;
1633 
1634         // See if we can use jdate to avoid date calculation.
1635         if (fixedDate != cachedFixedDate || fixedDate < 0) {
1636             jcal.getCalendarDateFromFixedDate(jdate, fixedDate);
1637             cachedFixedDate = fixedDate;
1638         }
1639         int era = getEraIndex(jdate);
1640         int year = jdate.getYear();
1641 
1642         // Always set the ERA and YEAR values.
1643         internalSet(ERA, era);
1644         internalSet(YEAR, year);
1645         int mask = fieldMask | (ERA_MASK|YEAR_MASK);
1646 
1647         int month =  jdate.getMonth() - 1; // 0-based
1648         int dayOfMonth = jdate.getDayOfMonth();
1649 
1650         // Set the basic date fields.
1651         if ((fieldMask & (MONTH_MASK|DAY_OF_MONTH_MASK|DAY_OF_WEEK_MASK))
1652             != 0) {
1653             internalSet(MONTH, month);
1654             internalSet(DAY_OF_MONTH, dayOfMonth);
1655             internalSet(DAY_OF_WEEK, jdate.getDayOfWeek());
1656             mask |= MONTH_MASK|DAY_OF_MONTH_MASK|DAY_OF_WEEK_MASK;
1657         }
1658 
1659         if ((fieldMask & (HOUR_OF_DAY_MASK|AM_PM_MASK|HOUR_MASK
1660                           |MINUTE_MASK|SECOND_MASK|MILLISECOND_MASK)) != 0) {
1661             if (timeOfDay != 0) {
1662                 int hours = timeOfDay / ONE_HOUR;
1663                 internalSet(HOUR_OF_DAY, hours);
1664                 internalSet(AM_PM, hours / 12); // Assume AM == 0
1665                 internalSet(HOUR, hours % 12);
1666                 int r = timeOfDay % ONE_HOUR;
1667                 internalSet(MINUTE, r / ONE_MINUTE);
1668                 r %= ONE_MINUTE;
1669                 internalSet(SECOND, r / ONE_SECOND);
1670                 internalSet(MILLISECOND, r % ONE_SECOND);
1671             } else {
1672                 internalSet(HOUR_OF_DAY, 0);
1673                 internalSet(AM_PM, AM);
1674                 internalSet(HOUR, 0);
1675                 internalSet(MINUTE, 0);
1676                 internalSet(SECOND, 0);
1677                 internalSet(MILLISECOND, 0);
1678             }
1679             mask |= (HOUR_OF_DAY_MASK|AM_PM_MASK|HOUR_MASK
1680                      |MINUTE_MASK|SECOND_MASK|MILLISECOND_MASK);
1681         }
1682 
1683         if ((fieldMask & (ZONE_OFFSET_MASK|DST_OFFSET_MASK)) != 0) {
1684             internalSet(ZONE_OFFSET, zoneOffsets[0]);
1685             internalSet(DST_OFFSET, zoneOffsets[1]);
1686             mask |= (ZONE_OFFSET_MASK|DST_OFFSET_MASK);
1687         }
1688 
1689         if ((fieldMask & (DAY_OF_YEAR_MASK|WEEK_OF_YEAR_MASK
1690                           |WEEK_OF_MONTH_MASK|DAY_OF_WEEK_IN_MONTH_MASK)) != 0) {
1691             int normalizedYear = jdate.getNormalizedYear();
1692             // If it's a year of an era transition, we need to handle
1693             // irregular year boundaries.
1694             boolean transitionYear = isTransitionYear(jdate.getNormalizedYear());
1695             int dayOfYear;
1696             long fixedDateJan1;
1697             if (transitionYear) {
1698                 fixedDateJan1 = getFixedDateJan1(jdate, fixedDate);
1699                 dayOfYear = (int)(fixedDate - fixedDateJan1) + 1;
1700             } else if (normalizedYear == MIN_VALUES[YEAR]) {
1701                 CalendarDate dx = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
1702                 fixedDateJan1 = jcal.getFixedDate(dx);
1703                 dayOfYear = (int)(fixedDate - fixedDateJan1) + 1;
1704             } else {
1705                 dayOfYear = (int) jcal.getDayOfYear(jdate);
1706                 fixedDateJan1 = fixedDate - dayOfYear + 1;
1707             }
1708             long fixedDateMonth1 = transitionYear ?
1709                 getFixedDateMonth1(jdate, fixedDate) : fixedDate - dayOfMonth + 1;
1710 
1711             internalSet(DAY_OF_YEAR, dayOfYear);
1712             internalSet(DAY_OF_WEEK_IN_MONTH, (dayOfMonth - 1) / 7 + 1);
1713 
1714             int weekOfYear = getWeekNumber(fixedDateJan1, fixedDate);
1715 
1716             // The spec is to calculate WEEK_OF_YEAR in the
1717             // ISO8601-style. This creates problems, though.
1718             if (weekOfYear == 0) {
1719                 // If the date belongs to the last week of the
1720                 // previous year, use the week number of "12/31" of
1721                 // the "previous" year. Again, if the previous year is
1722                 // a transition year, we need to take care of it.
1723                 // Usually the previous day of the first day of a year
1724                 // is December 31, which is not always true in the
1725                 // Japanese imperial calendar system.
1726                 long fixedDec31 = fixedDateJan1 - 1;
1727                 long prevJan1;
1728                 LocalGregorianCalendar.Date d = getCalendarDate(fixedDec31);
1729                 if (!(transitionYear || isTransitionYear(d.getNormalizedYear()))) {
1730                     prevJan1 = fixedDateJan1 - 365;
1731                     if (d.isLeapYear()) {
1732                         --prevJan1;
1733                     }
1734                 } else if (transitionYear) {
1735                     if (jdate.getYear() == 1) {
1736                         // As of Reiwa (since Meiji) there's no case
1737                         // that there are multiple transitions in a
1738                         // year.  Historically there was such
1739                         // case. There might be such case again in the
1740                         // future.
1741                         if (era > REIWA) {
1742                             CalendarDate pd = eras[era - 1].getSinceDate();
1743                             if (normalizedYear == pd.getYear()) {
1744                                 d.setMonth(pd.getMonth()).setDayOfMonth(pd.getDayOfMonth());
1745                             }
1746                         } else {
1747                             d.setMonth(LocalGregorianCalendar.JANUARY).setDayOfMonth(1);
1748                         }
1749                         jcal.normalize(d);
1750                         prevJan1 = jcal.getFixedDate(d);
1751                     } else {
1752                         prevJan1 = fixedDateJan1 - 365;
1753                         if (d.isLeapYear()) {
1754                             --prevJan1;
1755                         }
1756                     }
1757                 } else {
1758                     CalendarDate cd = eras[getEraIndex(jdate)].getSinceDate();
1759                     d.setMonth(cd.getMonth()).setDayOfMonth(cd.getDayOfMonth());
1760                     jcal.normalize(d);
1761                     prevJan1 = jcal.getFixedDate(d);
1762                 }
1763                 weekOfYear = getWeekNumber(prevJan1, fixedDec31);
1764             } else {
1765                 if (!transitionYear) {
1766                     // Regular years
1767                     if (weekOfYear >= 52) {
1768                         long nextJan1 = fixedDateJan1 + 365;
1769                         if (jdate.isLeapYear()) {
1770                             nextJan1++;
1771                         }
1772                         long nextJan1st = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(nextJan1 + 6,
1773                                                                                             getFirstDayOfWeek());
1774                         int ndays = (int)(nextJan1st - nextJan1);
1775                         if (ndays >= getMinimalDaysInFirstWeek() && fixedDate >= (nextJan1st - 7)) {
1776                             // The first days forms a week in which the date is included.
1777                             weekOfYear = 1;
1778                         }
1779                     }
1780                 } else {
1781                     LocalGregorianCalendar.Date d = (LocalGregorianCalendar.Date) jdate.clone();
1782                     long nextJan1;
1783                     if (jdate.getYear() == 1) {
1784                         d.addYear(+1);
1785                         d.setMonth(LocalGregorianCalendar.JANUARY).setDayOfMonth(1);
1786                         nextJan1 = jcal.getFixedDate(d);
1787                     } else {
1788                         int nextEraIndex = getEraIndex(d) + 1;
1789                         CalendarDate cd = eras[nextEraIndex].getSinceDate();
1790                         d.setEra(eras[nextEraIndex]);
1791                         d.setDate(1, cd.getMonth(), cd.getDayOfMonth());
1792                         jcal.normalize(d);
1793                         nextJan1 = jcal.getFixedDate(d);
1794                     }
1795                     long nextJan1st = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(nextJan1 + 6,
1796                                                                                         getFirstDayOfWeek());
1797                     int ndays = (int)(nextJan1st - nextJan1);
1798                     if (ndays >= getMinimalDaysInFirstWeek() && fixedDate >= (nextJan1st - 7)) {
1799                         // The first days forms a week in which the date is included.
1800                         weekOfYear = 1;
1801                     }
1802                 }
1803             }
1804             internalSet(WEEK_OF_YEAR, weekOfYear);
1805             internalSet(WEEK_OF_MONTH, getWeekNumber(fixedDateMonth1, fixedDate));
1806             mask |= (DAY_OF_YEAR_MASK|WEEK_OF_YEAR_MASK|WEEK_OF_MONTH_MASK|DAY_OF_WEEK_IN_MONTH_MASK);
1807         }
1808         return mask;
1809     }
1810 
1811     /**
1812      * Returns the number of weeks in a period between fixedDay1 and
1813      * fixedDate. The getFirstDayOfWeek-getMinimalDaysInFirstWeek rule
1814      * is applied to calculate the number of weeks.
1815      *
1816      * @param fixedDay1 the fixed date of the first day of the period
1817      * @param fixedDate the fixed date of the last day of the period
1818      * @return the number of weeks of the given period
1819      */
getWeekNumber(long fixedDay1, long fixedDate)1820     private int getWeekNumber(long fixedDay1, long fixedDate) {
1821         // We can always use `jcal' since Julian and Gregorian are the
1822         // same thing for this calculation.
1823         long fixedDay1st = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(fixedDay1 + 6,
1824                                                                              getFirstDayOfWeek());
1825         int ndays = (int)(fixedDay1st - fixedDay1);
1826         assert ndays <= 7;
1827         if (ndays >= getMinimalDaysInFirstWeek()) {
1828             fixedDay1st -= 7;
1829         }
1830         int normalizedDayOfPeriod = (int)(fixedDate - fixedDay1st);
1831         if (normalizedDayOfPeriod >= 0) {
1832             return normalizedDayOfPeriod / 7 + 1;
1833         }
1834         return CalendarUtils.floorDivide(normalizedDayOfPeriod, 7) + 1;
1835     }
1836 
1837     /**
1838      * Converts calendar field values to the time value (millisecond
1839      * offset from the <a href="Calendar.html#Epoch">Epoch</a>).
1840      *
1841      * @exception IllegalArgumentException if any calendar fields are invalid.
1842      */
computeTime()1843     protected void computeTime() {
1844         // In non-lenient mode, perform brief checking of calendar
1845         // fields which have been set externally. Through this
1846         // checking, the field values are stored in originalFields[]
1847         // to see if any of them are normalized later.
1848         if (!isLenient()) {
1849             if (originalFields == null) {
1850                 originalFields = new int[FIELD_COUNT];
1851             }
1852             for (int field = 0; field < FIELD_COUNT; field++) {
1853                 int value = internalGet(field);
1854                 if (isExternallySet(field)) {
1855                     // Quick validation for any out of range values
1856                     if (value < getMinimum(field) || value > getMaximum(field)) {
1857                         throw new IllegalArgumentException(getFieldName(field));
1858                     }
1859                 }
1860                 originalFields[field] = value;
1861             }
1862         }
1863 
1864         // Let the super class determine which calendar fields to be
1865         // used to calculate the time.
1866         int fieldMask = selectFields();
1867 
1868         int year;
1869         int era;
1870 
1871         if (isSet(ERA)) {
1872             era = internalGet(ERA);
1873             year = isSet(YEAR) ? internalGet(YEAR) : 1;
1874         } else {
1875             if (isSet(YEAR)) {
1876                 era = currentEra;
1877                 year = internalGet(YEAR);
1878             } else {
1879                 // Equivalent to 1970 (Gregorian)
1880                 era = SHOWA;
1881                 year = 45;
1882             }
1883         }
1884 
1885         // Calculate the time of day. We rely on the convention that
1886         // an UNSET field has 0.
1887         long timeOfDay = 0;
1888         if (isFieldSet(fieldMask, HOUR_OF_DAY)) {
1889             timeOfDay += (long) internalGet(HOUR_OF_DAY);
1890         } else {
1891             timeOfDay += internalGet(HOUR);
1892             // The default value of AM_PM is 0 which designates AM.
1893             if (isFieldSet(fieldMask, AM_PM)) {
1894                 timeOfDay += 12 * internalGet(AM_PM);
1895             }
1896         }
1897         timeOfDay *= 60;
1898         timeOfDay += internalGet(MINUTE);
1899         timeOfDay *= 60;
1900         timeOfDay += internalGet(SECOND);
1901         timeOfDay *= 1000;
1902         timeOfDay += internalGet(MILLISECOND);
1903 
1904         // Convert the time of day to the number of days and the
1905         // millisecond offset from midnight.
1906         long fixedDate = timeOfDay / ONE_DAY;
1907         timeOfDay %= ONE_DAY;
1908         while (timeOfDay < 0) {
1909             timeOfDay += ONE_DAY;
1910             --fixedDate;
1911         }
1912 
1913         // Calculate the fixed date since January 1, 1 (Gregorian).
1914         fixedDate += getFixedDate(era, year, fieldMask);
1915 
1916         // millis represents local wall-clock time in milliseconds.
1917         long millis = (fixedDate - EPOCH_OFFSET) * ONE_DAY + timeOfDay;
1918 
1919         // Compute the time zone offset and DST offset.  There are two potential
1920         // ambiguities here.  We'll assume a 2:00 am (wall time) switchover time
1921         // for discussion purposes here.
1922         // 1. The transition into DST.  Here, a designated time of 2:00 am - 2:59 am
1923         //    can be in standard or in DST depending.  However, 2:00 am is an invalid
1924         //    representation (the representation jumps from 1:59:59 am Std to 3:00:00 am DST).
1925         //    We assume standard time.
1926         // 2. The transition out of DST.  Here, a designated time of 1:00 am - 1:59 am
1927         //    can be in standard or DST.  Both are valid representations (the rep
1928         //    jumps from 1:59:59 DST to 1:00:00 Std).
1929         //    Again, we assume standard time.
1930         // We use the TimeZone object, unless the user has explicitly set the ZONE_OFFSET
1931         // or DST_OFFSET fields; then we use those fields.
1932         TimeZone zone = getZone();
1933         if (zoneOffsets == null) {
1934             zoneOffsets = new int[2];
1935         }
1936         int tzMask = fieldMask & (ZONE_OFFSET_MASK|DST_OFFSET_MASK);
1937         if (tzMask != (ZONE_OFFSET_MASK|DST_OFFSET_MASK)) {
1938             if (zone instanceof ZoneInfo) {
1939                 ((ZoneInfo)zone).getOffsetsByWall(millis, zoneOffsets);
1940             } else {
1941                 zone.getOffsets(millis - zone.getRawOffset(), zoneOffsets);
1942             }
1943         }
1944         if (tzMask != 0) {
1945             if (isFieldSet(tzMask, ZONE_OFFSET)) {
1946                 zoneOffsets[0] = internalGet(ZONE_OFFSET);
1947             }
1948             if (isFieldSet(tzMask, DST_OFFSET)) {
1949                 zoneOffsets[1] = internalGet(DST_OFFSET);
1950             }
1951         }
1952 
1953         // Adjust the time zone offset values to get the UTC time.
1954         millis -= zoneOffsets[0] + zoneOffsets[1];
1955 
1956         // Set this calendar's time in milliseconds
1957         time = millis;
1958 
1959         int mask = computeFields(fieldMask | getSetStateFields(), tzMask);
1960 
1961         if (!isLenient()) {
1962             for (int field = 0; field < FIELD_COUNT; field++) {
1963                 if (!isExternallySet(field)) {
1964                     continue;
1965                 }
1966                 if (originalFields[field] != internalGet(field)) {
1967                     int wrongValue = internalGet(field);
1968                     // Restore the original field values
1969                     System.arraycopy(originalFields, 0, fields, 0, fields.length);
1970                     throw new IllegalArgumentException(getFieldName(field) + "=" + wrongValue
1971                                                        + ", expected " + originalFields[field]);
1972                 }
1973             }
1974         }
1975         setFieldsNormalized(mask);
1976     }
1977 
1978     /**
1979      * Computes the fixed date under either the Gregorian or the
1980      * Julian calendar, using the given year and the specified calendar fields.
1981      *
1982      * @param era era index
1983      * @param year the normalized year number, with 0 indicating the
1984      * year 1 BCE, -1 indicating 2 BCE, etc.
1985      * @param fieldMask the calendar fields to be used for the date calculation
1986      * @return the fixed date
1987      * @see Calendar#selectFields
1988      */
getFixedDate(int era, int year, int fieldMask)1989     private long getFixedDate(int era, int year, int fieldMask) {
1990         int month = JANUARY;
1991         int firstDayOfMonth = 1;
1992         if (isFieldSet(fieldMask, MONTH)) {
1993             // No need to check if MONTH has been set (no isSet(MONTH)
1994             // call) since its unset value happens to be JANUARY (0).
1995             month = internalGet(MONTH);
1996 
1997             // If the month is out of range, adjust it into range.
1998             if (month > DECEMBER) {
1999                 year += month / 12;
2000                 month %= 12;
2001             } else if (month < JANUARY) {
2002                 int[] rem = new int[1];
2003                 year += CalendarUtils.floorDivide(month, 12, rem);
2004                 month = rem[0];
2005             }
2006         } else {
2007             if (year == 1 && era != 0) {
2008                 CalendarDate d = eras[era].getSinceDate();
2009                 month = d.getMonth() - 1;
2010                 firstDayOfMonth = d.getDayOfMonth();
2011             }
2012         }
2013 
2014         // Adjust the base date if year is the minimum value.
2015         if (year == MIN_VALUES[YEAR]) {
2016             CalendarDate dx = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
2017             int m = dx.getMonth() - 1;
2018             if (month < m) {
2019                 month = m;
2020             }
2021             if (month == m) {
2022                 firstDayOfMonth = dx.getDayOfMonth();
2023             }
2024         }
2025 
2026         LocalGregorianCalendar.Date date = jcal.newCalendarDate(TimeZone.NO_TIMEZONE);
2027         date.setEra(era > 0 ? eras[era] : null);
2028         date.setDate(year, month + 1, firstDayOfMonth);
2029         jcal.normalize(date);
2030 
2031         // Get the fixed date since Jan 1, 1 (Gregorian). We are on
2032         // the first day of either `month' or January in 'year'.
2033         long fixedDate = jcal.getFixedDate(date);
2034 
2035         if (isFieldSet(fieldMask, MONTH)) {
2036             // Month-based calculations
2037             if (isFieldSet(fieldMask, DAY_OF_MONTH)) {
2038                 // We are on the "first day" of the month (which may
2039                 // not be 1). Just add the offset if DAY_OF_MONTH is
2040                 // set. If the isSet call returns false, that means
2041                 // DAY_OF_MONTH has been selected just because of the
2042                 // selected combination. We don't need to add any
2043                 // since the default value is the "first day".
2044                 if (isSet(DAY_OF_MONTH)) {
2045                     // To avoid underflow with DAY_OF_MONTH-firstDayOfMonth, add
2046                     // DAY_OF_MONTH, then subtract firstDayOfMonth.
2047                     fixedDate += internalGet(DAY_OF_MONTH);
2048                     fixedDate -= firstDayOfMonth;
2049                 }
2050             } else {
2051                 if (isFieldSet(fieldMask, WEEK_OF_MONTH)) {
2052                     long firstDayOfWeek = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(fixedDate + 6,
2053                                                                                             getFirstDayOfWeek());
2054                     // If we have enough days in the first week, then
2055                     // move to the previous week.
2056                     if ((firstDayOfWeek - fixedDate) >= getMinimalDaysInFirstWeek()) {
2057                         firstDayOfWeek -= 7;
2058                     }
2059                     if (isFieldSet(fieldMask, DAY_OF_WEEK)) {
2060                         firstDayOfWeek = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(firstDayOfWeek + 6,
2061                                                                                            internalGet(DAY_OF_WEEK));
2062                     }
2063                     // In lenient mode, we treat days of the previous
2064                     // months as a part of the specified
2065                     // WEEK_OF_MONTH. See 4633646.
2066                     fixedDate = firstDayOfWeek + 7 * (internalGet(WEEK_OF_MONTH) - 1);
2067                 } else {
2068                     int dayOfWeek;
2069                     if (isFieldSet(fieldMask, DAY_OF_WEEK)) {
2070                         dayOfWeek = internalGet(DAY_OF_WEEK);
2071                     } else {
2072                         dayOfWeek = getFirstDayOfWeek();
2073                     }
2074                     // We are basing this on the day-of-week-in-month.  The only
2075                     // trickiness occurs if the day-of-week-in-month is
2076                     // negative.
2077                     int dowim;
2078                     if (isFieldSet(fieldMask, DAY_OF_WEEK_IN_MONTH)) {
2079                         dowim = internalGet(DAY_OF_WEEK_IN_MONTH);
2080                     } else {
2081                         dowim = 1;
2082                     }
2083                     if (dowim >= 0) {
2084                         fixedDate = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(fixedDate + (7 * dowim) - 1,
2085                                                                                       dayOfWeek);
2086                     } else {
2087                         // Go to the first day of the next week of
2088                         // the specified week boundary.
2089                         int lastDate = monthLength(month, year) + (7 * (dowim + 1));
2090                         // Then, get the day of week date on or before the last date.
2091                         fixedDate = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(fixedDate + lastDate - 1,
2092                                                                                       dayOfWeek);
2093                     }
2094                 }
2095             }
2096         } else {
2097             // We are on the first day of the year.
2098             if (isFieldSet(fieldMask, DAY_OF_YEAR)) {
2099                 if (isTransitionYear(date.getNormalizedYear())) {
2100                     fixedDate = getFixedDateJan1(date, fixedDate);
2101                 }
2102                 // Add the offset, then subtract 1. (Make sure to avoid underflow.)
2103                 fixedDate += internalGet(DAY_OF_YEAR);
2104                 fixedDate--;
2105             } else {
2106                 long firstDayOfWeek = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(fixedDate + 6,
2107                                                                                         getFirstDayOfWeek());
2108                 // If we have enough days in the first week, then move
2109                 // to the previous week.
2110                 if ((firstDayOfWeek - fixedDate) >= getMinimalDaysInFirstWeek()) {
2111                     firstDayOfWeek -= 7;
2112                 }
2113                 if (isFieldSet(fieldMask, DAY_OF_WEEK)) {
2114                     int dayOfWeek = internalGet(DAY_OF_WEEK);
2115                     if (dayOfWeek != getFirstDayOfWeek()) {
2116                         firstDayOfWeek = LocalGregorianCalendar.getDayOfWeekDateOnOrBefore(firstDayOfWeek + 6,
2117                                                                                            dayOfWeek);
2118                     }
2119                 }
2120                 fixedDate = firstDayOfWeek + 7 * ((long)internalGet(WEEK_OF_YEAR) - 1);
2121             }
2122         }
2123         return fixedDate;
2124     }
2125 
2126     /**
2127      * Returns the fixed date of the first day of the year (usually
2128      * January 1) before the specified date.
2129      *
2130      * @param date the date for which the first day of the year is
2131      * calculated. The date has to be in the cut-over year.
2132      * @param fixedDate the fixed date representation of the date
2133      */
getFixedDateJan1(LocalGregorianCalendar.Date date, long fixedDate)2134     private long getFixedDateJan1(LocalGregorianCalendar.Date date, long fixedDate) {
2135         Era era = date.getEra();
2136         if (date.getEra() != null && date.getYear() == 1) {
2137             for (int eraIndex = getEraIndex(date); eraIndex > 0; eraIndex--) {
2138                 CalendarDate d = eras[eraIndex].getSinceDate();
2139                 long fd = gcal.getFixedDate(d);
2140                 // There might be multiple era transitions in a year.
2141                 if (fd > fixedDate) {
2142                     continue;
2143                 }
2144                 return fd;
2145             }
2146         }
2147         CalendarDate d = gcal.newCalendarDate(TimeZone.NO_TIMEZONE);
2148         d.setDate(date.getNormalizedYear(), Gregorian.JANUARY, 1);
2149         return gcal.getFixedDate(d);
2150     }
2151 
2152     /**
2153      * Returns the fixed date of the first date of the month (usually
2154      * the 1st of the month) before the specified date.
2155      *
2156      * @param date the date for which the first day of the month is
2157      * calculated. The date must be in the era transition year.
2158      * @param fixedDate the fixed date representation of the date
2159      */
getFixedDateMonth1(LocalGregorianCalendar.Date date, long fixedDate)2160     private long getFixedDateMonth1(LocalGregorianCalendar.Date date,
2161                                           long fixedDate) {
2162         int eraIndex = getTransitionEraIndex(date);
2163         if (eraIndex != -1) {
2164             long transition = sinceFixedDates[eraIndex];
2165             // If the given date is on or after the transition date, then
2166             // return the transition date.
2167             if (transition <= fixedDate) {
2168                 return transition;
2169             }
2170         }
2171 
2172         // Otherwise, we can use the 1st day of the month.
2173         return fixedDate - date.getDayOfMonth() + 1;
2174     }
2175 
2176     /**
2177      * Returns a LocalGregorianCalendar.Date produced from the specified fixed date.
2178      *
2179      * @param fd the fixed date
2180      */
getCalendarDate(long fd)2181     private static LocalGregorianCalendar.Date getCalendarDate(long fd) {
2182         LocalGregorianCalendar.Date d = jcal.newCalendarDate(TimeZone.NO_TIMEZONE);
2183         jcal.getCalendarDateFromFixedDate(d, fd);
2184         return d;
2185     }
2186 
2187     /**
2188      * Returns the length of the specified month in the specified
2189      * Gregorian year. The year number must be normalized.
2190      *
2191      * @see GregorianCalendar#isLeapYear(int)
2192      */
monthLength(int month, int gregorianYear)2193     private int monthLength(int month, int gregorianYear) {
2194         return CalendarUtils.isGregorianLeapYear(gregorianYear) ?
2195             GregorianCalendar.LEAP_MONTH_LENGTH[month] : GregorianCalendar.MONTH_LENGTH[month];
2196     }
2197 
2198     /**
2199      * Returns the length of the specified month in the year provided
2200      * by internalGet(YEAR).
2201      *
2202      * @see GregorianCalendar#isLeapYear(int)
2203      */
monthLength(int month)2204     private int monthLength(int month) {
2205         assert jdate.isNormalized();
2206         return jdate.isLeapYear() ?
2207             GregorianCalendar.LEAP_MONTH_LENGTH[month] : GregorianCalendar.MONTH_LENGTH[month];
2208     }
2209 
actualMonthLength()2210     private int actualMonthLength() {
2211         int length = jcal.getMonthLength(jdate);
2212         int eraIndex = getTransitionEraIndex(jdate);
2213         if (eraIndex == -1) {
2214             long transitionFixedDate = sinceFixedDates[eraIndex];
2215             CalendarDate d = eras[eraIndex].getSinceDate();
2216             if (transitionFixedDate <= cachedFixedDate) {
2217                 length -= d.getDayOfMonth() - 1;
2218             } else {
2219                 length = d.getDayOfMonth() - 1;
2220             }
2221         }
2222         return length;
2223     }
2224 
2225     /**
2226      * Returns the index to the new era if the given date is in a
2227      * transition month.  For example, if the give date is Heisei 1
2228      * (1989) January 20, then the era index for Heisei is
2229      * returned. Likewise, if the given date is Showa 64 (1989)
2230      * January 3, then the era index for Heisei is returned. If the
2231      * given date is not in any transition month, then -1 is returned.
2232      */
getTransitionEraIndex(LocalGregorianCalendar.Date date)2233     private static int getTransitionEraIndex(LocalGregorianCalendar.Date date) {
2234         int eraIndex = getEraIndex(date);
2235         CalendarDate transitionDate = eras[eraIndex].getSinceDate();
2236         if (transitionDate.getYear() == date.getNormalizedYear() &&
2237             transitionDate.getMonth() == date.getMonth()) {
2238             return eraIndex;
2239         }
2240         if (eraIndex < eras.length - 1) {
2241             transitionDate = eras[++eraIndex].getSinceDate();
2242             if (transitionDate.getYear() == date.getNormalizedYear() &&
2243                 transitionDate.getMonth() == date.getMonth()) {
2244                 return eraIndex;
2245             }
2246         }
2247         return -1;
2248     }
2249 
isTransitionYear(int normalizedYear)2250     private boolean isTransitionYear(int normalizedYear) {
2251         for (int i = eras.length - 1; i > 0; i--) {
2252             int transitionYear = eras[i].getSinceDate().getYear();
2253             if (normalizedYear == transitionYear) {
2254                 return true;
2255             }
2256             if (normalizedYear > transitionYear) {
2257                 break;
2258             }
2259         }
2260         return false;
2261     }
2262 
getEraIndex(LocalGregorianCalendar.Date date)2263     private static int getEraIndex(LocalGregorianCalendar.Date date) {
2264         Era era = date.getEra();
2265         for (int i = eras.length - 1; i > 0; i--) {
2266             if (eras[i] == era) {
2267                 return i;
2268             }
2269         }
2270         return 0;
2271     }
2272 
2273     /**
2274      * Returns this object if it's normalized (all fields and time are
2275      * in sync). Otherwise, a cloned object is returned after calling
2276      * complete() in lenient mode.
2277      */
getNormalizedCalendar()2278     private JapaneseImperialCalendar getNormalizedCalendar() {
2279         JapaneseImperialCalendar jc;
2280         if (isFullyNormalized()) {
2281             jc = this;
2282         } else {
2283             // Create a clone and normalize the calendar fields
2284             jc = (JapaneseImperialCalendar) this.clone();
2285             jc.setLenient(true);
2286             jc.complete();
2287         }
2288         return jc;
2289     }
2290 
2291     /**
2292      * After adjustments such as add(MONTH), add(YEAR), we don't want the
2293      * month to jump around.  E.g., we don't want Jan 31 + 1 month to go to Mar
2294      * 3, we want it to go to Feb 28.  Adjustments which might run into this
2295      * problem call this method to retain the proper month.
2296      */
pinDayOfMonth(LocalGregorianCalendar.Date date)2297     private void pinDayOfMonth(LocalGregorianCalendar.Date date) {
2298         int year = date.getYear();
2299         int dom = date.getDayOfMonth();
2300         if (year != getMinimum(YEAR)) {
2301             date.setDayOfMonth(1);
2302             jcal.normalize(date);
2303             int monthLength = jcal.getMonthLength(date);
2304             if (dom > monthLength) {
2305                 date.setDayOfMonth(monthLength);
2306             } else {
2307                 date.setDayOfMonth(dom);
2308             }
2309             jcal.normalize(date);
2310         } else {
2311             LocalGregorianCalendar.Date d = jcal.getCalendarDate(Long.MIN_VALUE, getZone());
2312             LocalGregorianCalendar.Date realDate = jcal.getCalendarDate(time, getZone());
2313             long tod = realDate.getTimeOfDay();
2314             // Use an equivalent year.
2315             realDate.addYear(+400);
2316             realDate.setMonth(date.getMonth());
2317             realDate.setDayOfMonth(1);
2318             jcal.normalize(realDate);
2319             int monthLength = jcal.getMonthLength(realDate);
2320             if (dom > monthLength) {
2321                 realDate.setDayOfMonth(monthLength);
2322             } else {
2323                 if (dom < d.getDayOfMonth()) {
2324                     realDate.setDayOfMonth(d.getDayOfMonth());
2325                 } else {
2326                     realDate.setDayOfMonth(dom);
2327                 }
2328             }
2329             if (realDate.getDayOfMonth() == d.getDayOfMonth() && tod < d.getTimeOfDay()) {
2330                 realDate.setDayOfMonth(Math.min(dom + 1, monthLength));
2331             }
2332             // restore the year.
2333             date.setDate(year, realDate.getMonth(), realDate.getDayOfMonth());
2334             // Don't normalize date here so as not to cause underflow.
2335         }
2336     }
2337 
2338     /**
2339      * Returns the new value after 'roll'ing the specified value and amount.
2340      */
getRolledValue(int value, int amount, int min, int max)2341     private static int getRolledValue(int value, int amount, int min, int max) {
2342         assert value >= min && value <= max;
2343         int range = max - min + 1;
2344         amount %= range;
2345         int n = value + amount;
2346         if (n > max) {
2347             n -= range;
2348         } else if (n < min) {
2349             n += range;
2350         }
2351         assert n >= min && n <= max;
2352         return n;
2353     }
2354 
2355     /**
2356      * Returns the ERA.  We need a special method for this because the
2357      * default ERA is the current era, but a zero (unset) ERA means before Meiji.
2358      */
internalGetEra()2359     private int internalGetEra() {
2360         return isSet(ERA) ? internalGet(ERA) : currentEra;
2361     }
2362 
2363     /**
2364      * Updates internal state.
2365      */
readObject(ObjectInputStream stream)2366     private void readObject(ObjectInputStream stream)
2367             throws IOException, ClassNotFoundException {
2368         stream.defaultReadObject();
2369         if (jdate == null) {
2370             jdate = jcal.newCalendarDate(getZone());
2371             cachedFixedDate = Long.MIN_VALUE;
2372         }
2373     }
2374 }
2375