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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 ******************************************************************************
5 * Copyright (C) 2003-2016, International Business Machines Corporation
6 * and others. All Rights Reserved.
7 ******************************************************************************
8 *
9 * File HEBRWCAL.CPP
10 *
11 * Modification History:
12 *
13 *   Date        Name        Description
14 *   12/03/2003  srl         ported from java HebrewCalendar
15 *****************************************************************************
16 */
17 
18 #include "hebrwcal.h"
19 
20 #if !UCONFIG_NO_FORMATTING
21 
22 #include "cmemory.h"
23 #include "umutex.h"
24 #include <float.h>
25 #include "gregoimp.h" // Math
26 #include "astro.h" // CalendarAstronomer
27 #include "uhash.h"
28 #include "ucln_in.h"
29 
30 // Hebrew Calendar implementation
31 
32 /**
33 * The absolute date, in milliseconds since 1/1/1970 AD, Gregorian,
34 * of the start of the Hebrew calendar.  In order to keep this calendar's
35 * time of day in sync with that of the Gregorian calendar, we use
36 * midnight, rather than sunset the day before.
37 */
38 //static const double EPOCH_MILLIS = -180799862400000.; // 1/1/1 HY
39 
40 static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = {
41     // Minimum  Greatest    Least  Maximum
42     //           Minimum  Maximum
43     {        0,        0,        0,        0}, // ERA
44     { -5000000, -5000000,  5000000,  5000000}, // YEAR
45     {        0,        0,       12,       12}, // MONTH
46     {        1,        1,       51,       56}, // WEEK_OF_YEAR
47     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
48     {        1,        1,       29,       30}, // DAY_OF_MONTH
49     {        1,        1,      353,      385}, // DAY_OF_YEAR
50     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
51     {       -1,       -1,        5,        5}, // DAY_OF_WEEK_IN_MONTH
52     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
53     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
54     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
55     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
56     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
57     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
58     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
59     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
60     { -5000000, -5000000,  5000000,  5000000}, // YEAR_WOY
61     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
62     { -5000000, -5000000,  5000000,  5000000}, // EXTENDED_YEAR
63     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
64     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
65     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
66 };
67 
68 /**
69 * The lengths of the Hebrew months.  This is complicated, because there
70 * are three different types of years, or six if you count leap years.
71 * Due to the rules for postponing the start of the year to avoid having
72 * certain holidays fall on the sabbath, the year can end up being three
73 * different lengths, called "deficient", "normal", and "complete".
74 */
75 static const int8_t MONTH_LENGTH[][3] = {
76     // Deficient  Normal     Complete
77     {   30,         30,         30     },           //Tishri
78     {   29,         29,         30     },           //Heshvan
79     {   29,         30,         30     },           //Kislev
80     {   29,         29,         29     },           //Tevet
81     {   30,         30,         30     },           //Shevat
82     {   30,         30,         30     },           //Adar I (leap years only)
83     {   29,         29,         29     },           //Adar
84     {   30,         30,         30     },           //Nisan
85     {   29,         29,         29     },           //Iyar
86     {   30,         30,         30     },           //Sivan
87     {   29,         29,         29     },           //Tammuz
88     {   30,         30,         30     },           //Av
89     {   29,         29,         29     },           //Elul
90 };
91 
92 /**
93 * The cumulative # of days to the end of each month in a non-leap year
94 * Although this can be calculated from the MONTH_LENGTH table,
95 * keeping it around separately makes some calculations a lot faster
96 */
97 
98 static const int16_t MONTH_START[][3] = {
99     // Deficient  Normal     Complete
100     {    0,          0,          0  },          // (placeholder)
101     {   30,         30,         30  },          // Tishri
102     {   59,         59,         60  },          // Heshvan
103     {   88,         89,         90  },          // Kislev
104     {  117,        118,        119  },          // Tevet
105     {  147,        148,        149  },          // Shevat
106     {  147,        148,        149  },          // (Adar I placeholder)
107     {  176,        177,        178  },          // Adar
108     {  206,        207,        208  },          // Nisan
109     {  235,        236,        237  },          // Iyar
110     {  265,        266,        267  },          // Sivan
111     {  294,        295,        296  },          // Tammuz
112     {  324,        325,        326  },          // Av
113     {  353,        354,        355  },          // Elul
114 };
115 
116 /**
117 * The cumulative # of days to the end of each month in a leap year
118 */
119 static const int16_t  LEAP_MONTH_START[][3] = {
120     // Deficient  Normal     Complete
121     {    0,          0,          0  },          // (placeholder)
122     {   30,         30,         30  },          // Tishri
123     {   59,         59,         60  },          // Heshvan
124     {   88,         89,         90  },          // Kislev
125     {  117,        118,        119  },          // Tevet
126     {  147,        148,        149  },          // Shevat
127     {  177,        178,        179  },          // Adar I
128     {  206,        207,        208  },          // Adar II
129     {  236,        237,        238  },          // Nisan
130     {  265,        266,        267  },          // Iyar
131     {  295,        296,        297  },          // Sivan
132     {  324,        325,        326  },          // Tammuz
133     {  354,        355,        356  },          // Av
134     {  383,        384,        385  },          // Elul
135 };
136 
137 static icu::CalendarCache *gCache =  NULL;
138 
139 U_CDECL_BEGIN
calendar_hebrew_cleanup(void)140 static UBool calendar_hebrew_cleanup(void) {
141     delete gCache;
142     gCache = NULL;
143     return true;
144 }
145 U_CDECL_END
146 
147 U_NAMESPACE_BEGIN
148 //-------------------------------------------------------------------------
149 // Constructors...
150 //-------------------------------------------------------------------------
151 
152 /**
153 * Constructs a default <code>HebrewCalendar</code> using the current time
154 * in the default time zone with the default locale.
155 * @internal
156 */
HebrewCalendar(const Locale & aLocale,UErrorCode & success)157 HebrewCalendar::HebrewCalendar(const Locale& aLocale, UErrorCode& success)
158 :   Calendar(TimeZone::forLocaleOrDefault(aLocale), aLocale, success)
159 
160 {
161     setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
162 }
163 
164 
~HebrewCalendar()165 HebrewCalendar::~HebrewCalendar() {
166 }
167 
getType() const168 const char *HebrewCalendar::getType() const {
169     return "hebrew";
170 }
171 
clone() const172 HebrewCalendar* HebrewCalendar::clone() const {
173     return new HebrewCalendar(*this);
174 }
175 
HebrewCalendar(const HebrewCalendar & other)176 HebrewCalendar::HebrewCalendar(const HebrewCalendar& other) : Calendar(other) {
177 }
178 
179 
180 //-------------------------------------------------------------------------
181 // Rolling and adding functions overridden from Calendar
182 //
183 // These methods call through to the default implementation in IBMCalendar
184 // for most of the fields and only handle the unusual ones themselves.
185 //-------------------------------------------------------------------------
186 
187 /**
188 * Add a signed amount to a specified field, using this calendar's rules.
189 * For example, to add three days to the current date, you can call
190 * <code>add(Calendar.DATE, 3)</code>.
191 * <p>
192 * When adding to certain fields, the values of other fields may conflict and
193 * need to be changed.  For example, when adding one to the {@link #MONTH MONTH} field
194 * for the date "30 Av 5758", the {@link #DAY_OF_MONTH DAY_OF_MONTH} field
195 * must be adjusted so that the result is "29 Elul 5758" rather than the invalid
196 * "30 Elul 5758".
197 * <p>
198 * This method is able to add to
199 * all fields except for {@link #ERA ERA}, {@link #DST_OFFSET DST_OFFSET},
200 * and {@link #ZONE_OFFSET ZONE_OFFSET}.
201 * <p>
202 * <b>Note:</b> You should always use {@link #roll roll} and add rather
203 * than attempting to perform arithmetic operations directly on the fields
204 * of a <tt>HebrewCalendar</tt>.  Since the {@link #MONTH MONTH} field behaves
205 * discontinuously in non-leap years, simple arithmetic can give invalid results.
206 * <p>
207 * @param field     the time field.
208 * @param amount    the amount to add to the field.
209 *
210 * @exception   IllegalArgumentException if the field is invalid or refers
211 *              to a field that cannot be handled by this method.
212 * @internal
213 */
add(UCalendarDateFields field,int32_t amount,UErrorCode & status)214 void HebrewCalendar::add(UCalendarDateFields field, int32_t amount, UErrorCode& status)
215 {
216     if(U_FAILURE(status)) {
217         return;
218     }
219     switch (field) {
220   case UCAL_MONTH:
221       {
222           // We can't just do a set(MONTH, get(MONTH) + amount).  The
223           // reason is ADAR_1.  Suppose amount is +2 and we land in
224           // ADAR_1 -- then we have to bump to ADAR_2 aka ADAR.  But
225           // if amount is -2 and we land in ADAR_1, then we have to
226           // bump the other way -- down to SHEVAT.  - Alan 11/00
227           int32_t month = get(UCAL_MONTH, status);
228           int32_t year = get(UCAL_YEAR, status);
229           UBool acrossAdar1;
230           if (amount > 0) {
231               acrossAdar1 = (month < ADAR_1); // started before ADAR_1?
232               month += amount;
233               for (;;) {
234                   if (acrossAdar1 && month>=ADAR_1 && !isLeapYear(year)) {
235                       ++month;
236                   }
237                   if (month <= ELUL) {
238                       break;
239                   }
240                   month -= ELUL+1;
241                   ++year;
242                   acrossAdar1 = true;
243               }
244           } else {
245               acrossAdar1 = (month > ADAR_1); // started after ADAR_1?
246               month += amount;
247               for (;;) {
248                   if (acrossAdar1 && month<=ADAR_1 && !isLeapYear(year)) {
249                       --month;
250                   }
251                   if (month >= 0) {
252                       break;
253                   }
254                   month += ELUL+1;
255                   --year;
256                   acrossAdar1 = true;
257               }
258           }
259           set(UCAL_MONTH, month);
260           set(UCAL_YEAR, year);
261           pinField(UCAL_DAY_OF_MONTH, status);
262           break;
263       }
264 
265   default:
266       Calendar::add(field, amount, status);
267       break;
268     }
269 }
270 
271 /**
272 * @deprecated ICU 2.6 use UCalendarDateFields instead of EDateFields
273 */
add(EDateFields field,int32_t amount,UErrorCode & status)274 void HebrewCalendar::add(EDateFields field, int32_t amount, UErrorCode& status)
275 {
276     add((UCalendarDateFields)field, amount, status);
277 }
278 
279 /**
280 * Rolls (up/down) a specified amount time on the given field.  For
281 * example, to roll the current date up by three days, you can call
282 * <code>roll(Calendar.DATE, 3)</code>.  If the
283 * field is rolled past its maximum allowable value, it will "wrap" back
284 * to its minimum and continue rolling.
285 * For example, calling <code>roll(Calendar.DATE, 10)</code>
286 * on a Hebrew calendar set to "25 Av 5758" will result in the date "5 Av 5758".
287 * <p>
288 * When rolling certain fields, the values of other fields may conflict and
289 * need to be changed.  For example, when rolling the {@link #MONTH MONTH} field
290 * upward by one for the date "30 Av 5758", the {@link #DAY_OF_MONTH DAY_OF_MONTH} field
291 * must be adjusted so that the result is "29 Elul 5758" rather than the invalid
292 * "30 Elul".
293 * <p>
294 * This method is able to roll
295 * all fields except for {@link #ERA ERA}, {@link #DST_OFFSET DST_OFFSET},
296 * and {@link #ZONE_OFFSET ZONE_OFFSET}.  Subclasses may, of course, add support for
297 * additional fields in their overrides of <code>roll</code>.
298 * <p>
299 * <b>Note:</b> You should always use roll and {@link #add add} rather
300 * than attempting to perform arithmetic operations directly on the fields
301 * of a <tt>HebrewCalendar</tt>.  Since the {@link #MONTH MONTH} field behaves
302 * discontinuously in non-leap years, simple arithmetic can give invalid results.
303 * <p>
304 * @param field     the time field.
305 * @param amount    the amount by which the field should be rolled.
306 *
307 * @exception   IllegalArgumentException if the field is invalid or refers
308 *              to a field that cannot be handled by this method.
309 * @internal
310 */
roll(UCalendarDateFields field,int32_t amount,UErrorCode & status)311 void HebrewCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status)
312 {
313     if(U_FAILURE(status)) {
314         return;
315     }
316     switch (field) {
317   case UCAL_MONTH:
318       {
319           int32_t month = get(UCAL_MONTH, status);
320           int32_t year = get(UCAL_YEAR, status);
321 
322           UBool leapYear = isLeapYear(year);
323           int32_t yearLength = monthsInYear(year);
324           int32_t newMonth = month + (amount % yearLength);
325           //
326           // If it's not a leap year and we're rolling past the missing month
327           // of ADAR_1, we need to roll an extra month to make up for it.
328           //
329           if (!leapYear) {
330               if (amount > 0 && month < ADAR_1 && newMonth >= ADAR_1) {
331                   newMonth++;
332               } else if (amount < 0 && month > ADAR_1 && newMonth <= ADAR_1) {
333                   newMonth--;
334               }
335           }
336           set(UCAL_MONTH, (newMonth + 13) % 13);
337           pinField(UCAL_DAY_OF_MONTH, status);
338           return;
339       }
340   default:
341       Calendar::roll(field, amount, status);
342     }
343 }
344 
roll(EDateFields field,int32_t amount,UErrorCode & status)345 void HebrewCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status) {
346     roll((UCalendarDateFields)field, amount, status);
347 }
348 
349 //-------------------------------------------------------------------------
350 // Support methods
351 //-------------------------------------------------------------------------
352 
353 // Hebrew date calculations are performed in terms of days, hours, and
354 // "parts" (or halakim), which are 1/1080 of an hour, or 3 1/3 seconds.
355 static const int32_t HOUR_PARTS = 1080;
356 static const int32_t DAY_PARTS  = 24*HOUR_PARTS;
357 
358 // An approximate value for the length of a lunar month.
359 // It is used to calculate the approximate year and month of a given
360 // absolute date.
361 static const int32_t  MONTH_DAYS = 29;
362 static const int32_t MONTH_FRACT = 12*HOUR_PARTS + 793;
363 static const int32_t MONTH_PARTS = MONTH_DAYS*DAY_PARTS + MONTH_FRACT;
364 
365 // The time of the new moon (in parts) on 1 Tishri, year 1 (the epoch)
366 // counting from noon on the day before.  BAHARAD is an abbreviation of
367 // Bet (Monday), Hey (5 hours from sunset), Resh-Daled (204).
368 static const int32_t BAHARAD = 11*HOUR_PARTS + 204;
369 
370 /**
371 * Finds the day # of the first day in the given Hebrew year.
372 * To do this, we want to calculate the time of the Tishri 1 new moon
373 * in that year.
374 * <p>
375 * The algorithm here is similar to ones described in a number of
376 * references, including:
377 * <ul>
378 * <li>"Calendrical Calculations", by Nachum Dershowitz & Edward Reingold,
379 *     Cambridge University Press, 1997, pages 85-91.
380 *
381 * <li>Hebrew Calendar Science and Myths,
382 *     <a href="http://www.geocities.com/Athens/1584/">
383 *     http://www.geocities.com/Athens/1584/</a>
384 *
385 * <li>The Calendar FAQ,
386 *      <a href="http://www.faqs.org/faqs/calendars/faq/">
387 *      http://www.faqs.org/faqs/calendars/faq/</a>
388 * </ul>
389 */
startOfYear(int32_t year,UErrorCode & status)390 int32_t HebrewCalendar::startOfYear(int32_t year, UErrorCode &status)
391 {
392     ucln_i18n_registerCleanup(UCLN_I18N_HEBREW_CALENDAR, calendar_hebrew_cleanup);
393     int32_t day = CalendarCache::get(&gCache, year, status);
394 
395     if (day == 0) {
396         // # of months before year
397         int32_t months = (int32_t)ClockMath::floorDivide((235 * (int64_t)year - 234), (int64_t)19);
398 
399         int64_t frac = (int64_t)months * MONTH_FRACT + BAHARAD;  // Fractional part of day #
400         day  = months * 29 + (int32_t)(frac / DAY_PARTS);        // Whole # part of calculation
401         frac = frac % DAY_PARTS;                        // Time of day
402 
403         int32_t wd = (day % 7);                        // Day of week (0 == Monday)
404 
405         if (wd == 2 || wd == 4 || wd == 6) {
406             // If the 1st is on Sun, Wed, or Fri, postpone to the next day
407             day += 1;
408             wd = (day % 7);
409         }
410         if (wd == 1 && frac > 15*HOUR_PARTS+204 && !isLeapYear(year) ) {
411             // If the new moon falls after 3:11:20am (15h204p from the previous noon)
412             // on a Tuesday and it is not a leap year, postpone by 2 days.
413             // This prevents 356-day years.
414             day += 2;
415         }
416         else if (wd == 0 && frac > 21*HOUR_PARTS+589 && isLeapYear(year-1) ) {
417             // If the new moon falls after 9:32:43 1/3am (21h589p from yesterday noon)
418             // on a Monday and *last* year was a leap year, postpone by 1 day.
419             // Prevents 382-day years.
420             day += 1;
421         }
422         CalendarCache::put(&gCache, year, day, status);
423     }
424     return day;
425 }
426 
427 /**
428 * Find the day of the week for a given day
429 *
430 * @param day   The # of days since the start of the Hebrew calendar,
431 *              1-based (i.e. 1/1/1 AM is day 1).
432 */
absoluteDayToDayOfWeek(int32_t day)433 int32_t HebrewCalendar::absoluteDayToDayOfWeek(int32_t day)
434 {
435     // We know that 1/1/1 AM is a Monday, which makes the math easy...
436     return (day % 7) + 1;
437 }
438 
439 /**
440 * Returns the the type of a given year.
441 *  0   "Deficient" year with 353 or 383 days
442 *  1   "Normal"    year with 354 or 384 days
443 *  2   "Complete"  year with 355 or 385 days
444 */
yearType(int32_t year) const445 int32_t HebrewCalendar::yearType(int32_t year) const
446 {
447     int32_t yearLength = handleGetYearLength(year);
448 
449     if (yearLength > 380) {
450         yearLength -= 30;        // Subtract length of leap month.
451     }
452 
453     int type = 0;
454 
455     switch (yearLength) {
456   case 353:
457       type = 0; break;
458   case 354:
459       type = 1; break;
460   case 355:
461       type = 2; break;
462   default:
463       //throw new RuntimeException("Illegal year length " + yearLength + " in year " + year);
464       type = 1;
465     }
466     return type;
467 }
468 
469 /**
470 * Determine whether a given Hebrew year is a leap year
471 *
472 * The rule here is that if (year % 19) == 0, 3, 6, 8, 11, 14, or 17.
473 * The formula below performs the same test, believe it or not.
474 */
isLeapYear(int32_t year)475 UBool HebrewCalendar::isLeapYear(int32_t year) {
476     //return (year * 12 + 17) % 19 >= 12;
477     int32_t x = (year*12 + 17) % 19;
478     return x >= ((x < 0) ? -7 : 12);
479 }
480 
monthsInYear(int32_t year)481 int32_t HebrewCalendar::monthsInYear(int32_t year) {
482     return isLeapYear(year) ? 13 : 12;
483 }
484 
485 //-------------------------------------------------------------------------
486 // Calendar framework
487 //-------------------------------------------------------------------------
488 
489 /**
490 * @internal
491 */
handleGetLimit(UCalendarDateFields field,ELimitType limitType) const492 int32_t HebrewCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
493     return LIMITS[field][limitType];
494 }
495 
496 /**
497 * Returns the length of the given month in the given year
498 * @internal
499 */
handleGetMonthLength(int32_t extendedYear,int32_t month) const500 int32_t HebrewCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
501     // Resolve out-of-range months.  This is necessary in order to
502     // obtain the correct year.  We correct to
503     // a 12- or 13-month year (add/subtract 12 or 13, depending
504     // on the year) but since we _always_ number from 0..12, and
505     // the leap year determines whether or not month 5 (Adar 1)
506     // is present, we allow 0..12 in any given year.
507     while (month < 0) {
508         month += monthsInYear(--extendedYear);
509     }
510     // Careful: allow 0..12 in all years
511     while (month > 12) {
512         month -= monthsInYear(extendedYear++);
513     }
514 
515     switch (month) {
516     case HESHVAN:
517     case KISLEV:
518       // These two month lengths can vary
519       return MONTH_LENGTH[month][yearType(extendedYear)];
520 
521     default:
522       // The rest are a fixed length
523       return MONTH_LENGTH[month][0];
524     }
525 }
526 
527 /**
528 * Returns the number of days in the given Hebrew year
529 * @internal
530 */
handleGetYearLength(int32_t eyear) const531 int32_t HebrewCalendar::handleGetYearLength(int32_t eyear) const {
532     UErrorCode status = U_ZERO_ERROR;
533     return startOfYear(eyear+1, status) - startOfYear(eyear, status);
534 }
535 
validateField(UCalendarDateFields field,UErrorCode & status)536 void HebrewCalendar::validateField(UCalendarDateFields field, UErrorCode &status) {
537     if (field == UCAL_MONTH && !isLeapYear(handleGetExtendedYear()) && internalGet(UCAL_MONTH) == ADAR_1) {
538         status = U_ILLEGAL_ARGUMENT_ERROR;
539         return;
540     }
541     Calendar::validateField(field, status);
542 }
543 //-------------------------------------------------------------------------
544 // Functions for converting from milliseconds to field values
545 //-------------------------------------------------------------------------
546 
547 /**
548 * Subclasses may override this method to compute several fields
549 * specific to each calendar system.  These are:
550 *
551 * <ul><li>ERA
552 * <li>YEAR
553 * <li>MONTH
554 * <li>DAY_OF_MONTH
555 * <li>DAY_OF_YEAR
556 * <li>EXTENDED_YEAR</ul>
557 *
558 * Subclasses can refer to the DAY_OF_WEEK and DOW_LOCAL fields,
559 * which will be set when this method is called.  Subclasses can
560 * also call the getGregorianXxx() methods to obtain Gregorian
561 * calendar equivalents for the given Julian day.
562 *
563 * <p>In addition, subclasses should compute any subclass-specific
564 * fields, that is, fields from BASE_FIELD_COUNT to
565 * getFieldCount() - 1.
566 * @internal
567 */
handleComputeFields(int32_t julianDay,UErrorCode & status)568 void HebrewCalendar::handleComputeFields(int32_t julianDay, UErrorCode &status) {
569     int32_t d = julianDay - 347997;
570     double m = ClockMath::floorDivide((d * (double)DAY_PARTS), (double) MONTH_PARTS);  // Months (approx)
571     int32_t year = (int32_t)(ClockMath::floorDivide((19. * m + 234.), 235.) + 1.);     // Years (approx)
572     int32_t ys  = startOfYear(year, status);                   // 1st day of year
573     int32_t dayOfYear = (d - ys);
574 
575     // Because of the postponement rules, it's possible to guess wrong.  Fix it.
576     while (dayOfYear < 1) {
577         year--;
578         ys  = startOfYear(year, status);
579         dayOfYear = (d - ys);
580     }
581 
582     // Now figure out which month we're in, and the date within that month
583     int32_t type = yearType(year);
584     UBool isLeap = isLeapYear(year);
585 
586     int32_t month = 0;
587     int32_t momax = UPRV_LENGTHOF(MONTH_START);
588     while (month < momax && dayOfYear > (  isLeap ? LEAP_MONTH_START[month][type] : MONTH_START[month][type] ) ) {
589         month++;
590     }
591     if (month >= momax || month<=0) {
592         // TODO: I found dayOfYear could be out of range when
593         // a large value is set to julianDay.  I patched startOfYear
594         // to reduce the chace, but it could be still reproduced either
595         // by startOfYear or other places.  For now, we check
596         // the month is in valid range to avoid out of array index
597         // access problem here.  However, we need to carefully review
598         // the calendar implementation to check the extreme limit of
599         // each calendar field and the code works well for any values
600         // in the valid value range.  -yoshito
601         status = U_ILLEGAL_ARGUMENT_ERROR;
602         return;
603     }
604     month--;
605     int dayOfMonth = dayOfYear - (isLeap ? LEAP_MONTH_START[month][type] : MONTH_START[month][type]);
606 
607     internalSet(UCAL_ERA, 0);
608     internalSet(UCAL_YEAR, year);
609     internalSet(UCAL_EXTENDED_YEAR, year);
610     internalSet(UCAL_MONTH, month);
611     internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
612     internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
613 }
614 
615 //-------------------------------------------------------------------------
616 // Functions for converting from field values to milliseconds
617 //-------------------------------------------------------------------------
618 
619 /**
620 * @internal
621 */
handleGetExtendedYear()622 int32_t HebrewCalendar::handleGetExtendedYear() {
623     int32_t year;
624     if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) {
625         year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
626     } else {
627         year = internalGet(UCAL_YEAR, 1); // Default to year 1
628     }
629     return year;
630 }
631 
632 /**
633 * Return JD of start of given month/year.
634 * @internal
635 */
handleComputeMonthStart(int32_t eyear,int32_t month,UBool) const636 int32_t HebrewCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool /*useMonth*/) const {
637     UErrorCode status = U_ZERO_ERROR;
638     // Resolve out-of-range months.  This is necessary in order to
639     // obtain the correct year.  We correct to
640     // a 12- or 13-month year (add/subtract 12 or 13, depending
641     // on the year) but since we _always_ number from 0..12, and
642     // the leap year determines whether or not month 5 (Adar 1)
643     // is present, we allow 0..12 in any given year.
644     while (month < 0) {
645         month += monthsInYear(--eyear);
646     }
647     // Careful: allow 0..12 in all years
648     while (month > 12) {
649         month -= monthsInYear(eyear++);
650     }
651 
652     int32_t day = startOfYear(eyear, status);
653 
654     if(U_FAILURE(status)) {
655         return 0;
656     }
657 
658     if (month != 0) {
659         if (isLeapYear(eyear)) {
660             day += LEAP_MONTH_START[month][yearType(eyear)];
661         } else {
662             day += MONTH_START[month][yearType(eyear)];
663         }
664     }
665 
666     return (int) (day + 347997);
667 }
668 
669 UBool
inDaylightTime(UErrorCode & status) const670 HebrewCalendar::inDaylightTime(UErrorCode& status) const
671 {
672     // copied from GregorianCalendar
673     if (U_FAILURE(status) || !getTimeZone().useDaylightTime())
674         return false;
675 
676     // Force an update of the state of the Calendar.
677     ((HebrewCalendar*)this)->complete(status); // cast away const
678 
679     return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : false);
680 }
681 
682 /**
683  * The system maintains a static default century start date and Year.  They are
684  * initialized the first time they are used.  Once the system default century date
685  * and year are set, they do not change.
686  */
687 static UDate           gSystemDefaultCenturyStart       = DBL_MIN;
688 static int32_t         gSystemDefaultCenturyStartYear   = -1;
689 static icu::UInitOnce  gSystemDefaultCenturyInit        {};
690 
haveDefaultCentury() const691 UBool HebrewCalendar::haveDefaultCentury() const
692 {
693     return true;
694 }
695 
initializeSystemDefaultCentury()696 static void U_CALLCONV initializeSystemDefaultCentury()
697 {
698     // initialize systemDefaultCentury and systemDefaultCenturyYear based
699     // on the current time.  They'll be set to 80 years before
700     // the current time.
701     UErrorCode status = U_ZERO_ERROR;
702     HebrewCalendar calendar(Locale("@calendar=hebrew"),status);
703     if (U_SUCCESS(status)) {
704         calendar.setTime(Calendar::getNow(), status);
705         calendar.add(UCAL_YEAR, -80, status);
706 
707         gSystemDefaultCenturyStart = calendar.getTime(status);
708         gSystemDefaultCenturyStartYear = calendar.get(UCAL_YEAR, status);
709     }
710     // We have no recourse upon failure unless we want to propagate the failure
711     // out.
712 }
713 
714 
defaultCenturyStart() const715 UDate HebrewCalendar::defaultCenturyStart() const {
716     // lazy-evaluate systemDefaultCenturyStart
717     umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
718     return gSystemDefaultCenturyStart;
719 }
720 
defaultCenturyStartYear() const721 int32_t HebrewCalendar::defaultCenturyStartYear() const {
722     // lazy-evaluate systemDefaultCenturyStartYear
723     umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
724     return gSystemDefaultCenturyStartYear;
725 }
726 
727 
728 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(HebrewCalendar)
729 
730 U_NAMESPACE_END
731 
732 #endif // UCONFIG_NO_FORMATTING
733 
734