1// © 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3/*
4* Copyright (C) 1997-2013, International Business Machines Corporation and others.
5* All Rights Reserved.
6********************************************************************************
7*
8* File GREGOCAL.H
9*
10* Modification History:
11*
12* Date Name Description
13* 04/22/97 aliu Overhauled header.
14* 07/28/98 stephen Sync with JDK 1.2
15* 09/04/98 stephen Re-sync with JDK 8/31 putback
16* 09/14/98 stephen Changed type of kOneDay, kOneWeek to double.
17* Fixed bug in roll()
18* 10/15/99 aliu Fixed j31, incorrect WEEK_OF_YEAR computation.
19* Added documentation of WEEK_OF_YEAR computation.
20* 10/15/99 aliu Fixed j32, cannot set date to Feb 29 2000 AD.
21* {JDK bug 4210209 4209272}
22* 11/07/2003 srl Update, clean up documentation.
23********************************************************************************
24*/
25
26#ifndef GREGOCAL_H
27#define GREGOCAL_H
28
29#include "unicode/utypes.h"
30
31#if U_SHOW_CPLUSPLUS_API
32
33#if !UCONFIG_NO_FORMATTING
34
35#include "unicode/calendar.h"
36
37/**
38 * \file
39 * \brief C++ API: Concrete class which provides the standard calendar.
40 */
41
42U_NAMESPACE_BEGIN
43
44/**
45 * Concrete class which provides the standard calendar used by most of the world.
46 * <P>
47 * The standard (Gregorian) calendar has 2 eras, BC and AD.
48 * <P>
49 * This implementation handles a single discontinuity, which corresponds by default to
50 * the date the Gregorian calendar was originally instituted (October 15, 1582). Not all
51 * countries adopted the Gregorian calendar then, so this cutover date may be changed by
52 * the caller.
53 * <P>
54 * Prior to the institution of the Gregorian Calendar, New Year's Day was March 25. To
55 * avoid confusion, this Calendar always uses January 1. A manual adjustment may be made
56 * if desired for dates that are prior to the Gregorian changeover and which fall
57 * between January 1 and March 24.
58 *
59 * <p>Values calculated for the <code>WEEK_OF_YEAR</code> field range from 1 to
60 * 53. Week 1 for a year is the first week that contains at least
61 * <code>getMinimalDaysInFirstWeek()</code> days from that year. It thus
62 * depends on the values of <code>getMinimalDaysInFirstWeek()</code>,
63 * <code>getFirstDayOfWeek()</code>, and the day of the week of January 1.
64 * Weeks between week 1 of one year and week 1 of the following year are
65 * numbered sequentially from 2 to 52 or 53 (as needed).
66 *
67 * <p>For example, January 1, 1998 was a Thursday. If
68 * <code>getFirstDayOfWeek()</code> is <code>MONDAY</code> and
69 * <code>getMinimalDaysInFirstWeek()</code> is 4 (these are the values
70 * reflecting ISO 8601 and many national standards), then week 1 of 1998 starts
71 * on December 29, 1997, and ends on January 4, 1998. If, however,
72 * <code>getFirstDayOfWeek()</code> is <code>SUNDAY</code>, then week 1 of 1998
73 * starts on January 4, 1998, and ends on January 10, 1998; the first three days
74 * of 1998 then are part of week 53 of 1997.
75 *
76 * <p>Example for using GregorianCalendar:
77 * <pre>
78 * \code
79 * // get the supported ids for GMT-08:00 (Pacific Standard Time)
80 * UErrorCode success = U_ZERO_ERROR;
81 * const StringEnumeration *ids = TimeZone::createEnumeration(-8 * 60 * 60 * 1000, success);
82 * // if no ids were returned, something is wrong. get out.
83 * if (U_FAILURE(success)) {
84 * return;
85 * }
86 *
87 * // begin output
88 * cout << "Current Time" << endl;
89 *
90 * // create a Pacific Standard Time time zone
91 * SimpleTimeZone* pdt = new SimpleTimeZone(-8 * 60 * 60 * 1000, ids->unext(NULL, success)));
92 *
93 * // set up rules for daylight savings time
94 * pdt->setStartRule(UCAL_MARCH, 1, UCAL_SUNDAY, 2 * 60 * 60 * 1000);
95 * pdt->setEndRule(UCAL_NOVEMBER, 2, UCAL_SUNDAY, 2 * 60 * 60 * 1000);
96 *
97 * // create a GregorianCalendar with the Pacific Daylight time zone
98 * // and the current date and time
99 * Calendar* calendar = new GregorianCalendar( pdt, success );
100 *
101 * // print out a bunch of interesting things
102 * cout << "ERA: " << calendar->get( UCAL_ERA, success ) << endl;
103 * cout << "YEAR: " << calendar->get( UCAL_YEAR, success ) << endl;
104 * cout << "MONTH: " << calendar->get( UCAL_MONTH, success ) << endl;
105 * cout << "WEEK_OF_YEAR: " << calendar->get( UCAL_WEEK_OF_YEAR, success ) << endl;
106 * cout << "WEEK_OF_MONTH: " << calendar->get( UCAL_WEEK_OF_MONTH, success ) << endl;
107 * cout << "DATE: " << calendar->get( UCAL_DATE, success ) << endl;
108 * cout << "DAY_OF_MONTH: " << calendar->get( UCAL_DAY_OF_MONTH, success ) << endl;
109 * cout << "DAY_OF_YEAR: " << calendar->get( UCAL_DAY_OF_YEAR, success ) << endl;
110 * cout << "DAY_OF_WEEK: " << calendar->get( UCAL_DAY_OF_WEEK, success ) << endl;
111 * cout << "DAY_OF_WEEK_IN_MONTH: " << calendar->get( UCAL_DAY_OF_WEEK_IN_MONTH, success ) << endl;
112 * cout << "AM_PM: " << calendar->get( UCAL_AM_PM, success ) << endl;
113 * cout << "HOUR: " << calendar->get( UCAL_HOUR, success ) << endl;
114 * cout << "HOUR_OF_DAY: " << calendar->get( UCAL_HOUR_OF_DAY, success ) << endl;
115 * cout << "MINUTE: " << calendar->get( UCAL_MINUTE, success ) << endl;
116 * cout << "SECOND: " << calendar->get( UCAL_SECOND, success ) << endl;
117 * cout << "MILLISECOND: " << calendar->get( UCAL_MILLISECOND, success ) << endl;
118 * cout << "ZONE_OFFSET: " << (calendar->get( UCAL_ZONE_OFFSET, success )/(60*60*1000)) << endl;
119 * cout << "DST_OFFSET: " << (calendar->get( UCAL_DST_OFFSET, success )/(60*60*1000)) << endl;
120 *
121 * cout << "Current Time, with hour reset to 3" << endl;
122 * calendar->clear(UCAL_HOUR_OF_DAY); // so doesn't override
123 * calendar->set(UCAL_HOUR, 3);
124 * cout << "ERA: " << calendar->get( UCAL_ERA, success ) << endl;
125 * cout << "YEAR: " << calendar->get( UCAL_YEAR, success ) << endl;
126 * cout << "MONTH: " << calendar->get( UCAL_MONTH, success ) << endl;
127 * cout << "WEEK_OF_YEAR: " << calendar->get( UCAL_WEEK_OF_YEAR, success ) << endl;
128 * cout << "WEEK_OF_MONTH: " << calendar->get( UCAL_WEEK_OF_MONTH, success ) << endl;
129 * cout << "DATE: " << calendar->get( UCAL_DATE, success ) << endl;
130 * cout << "DAY_OF_MONTH: " << calendar->get( UCAL_DAY_OF_MONTH, success ) << endl;
131 * cout << "DAY_OF_YEAR: " << calendar->get( UCAL_DAY_OF_YEAR, success ) << endl;
132 * cout << "DAY_OF_WEEK: " << calendar->get( UCAL_DAY_OF_WEEK, success ) << endl;
133 * cout << "DAY_OF_WEEK_IN_MONTH: " << calendar->get( UCAL_DAY_OF_WEEK_IN_MONTH, success ) << endl;
134 * cout << "AM_PM: " << calendar->get( UCAL_AM_PM, success ) << endl;
135 * cout << "HOUR: " << calendar->get( UCAL_HOUR, success ) << endl;
136 * cout << "HOUR_OF_DAY: " << calendar->get( UCAL_HOUR_OF_DAY, success ) << endl;
137 * cout << "MINUTE: " << calendar->get( UCAL_MINUTE, success ) << endl;
138 * cout << "SECOND: " << calendar->get( UCAL_SECOND, success ) << endl;
139 * cout << "MILLISECOND: " << calendar->get( UCAL_MILLISECOND, success ) << endl;
140 * cout << "ZONE_OFFSET: " << (calendar->get( UCAL_ZONE_OFFSET, success )/(60*60*1000)) << endl; // in hours
141 * cout << "DST_OFFSET: " << (calendar->get( UCAL_DST_OFFSET, success )/(60*60*1000)) << endl; // in hours
142 *
143 * if (U_FAILURE(success)) {
144 * cout << "An error occurred. success=" << u_errorName(success) << endl;
145 * }
146 *
147 * delete ids;
148 * delete calendar; // also deletes pdt
149 * \endcode
150 * </pre>
151 * @stable ICU 2.0
152 */
153class U_I18N_API GregorianCalendar: public Calendar {
154public:
155
156 /**
157 * Useful constants for GregorianCalendar and TimeZone.
158 * @stable ICU 2.0
159 */
160 enum EEras {
161 BC,
162 AD
163 };
164
165 /**
166 * Constructs a default GregorianCalendar using the current time in the default time
167 * zone with the default locale.
168 *
169 * @param success Indicates the status of GregorianCalendar object construction.
170 * Returns U_ZERO_ERROR if constructed successfully.
171 * @stable ICU 2.0
172 */
173 GregorianCalendar(UErrorCode& success);
174
175 /**
176 * Constructs a GregorianCalendar based on the current time in the given time zone
177 * with the default locale. Clients are no longer responsible for deleting the given
178 * time zone object after it's adopted.
179 *
180 * @param zoneToAdopt The given timezone.
181 * @param success Indicates the status of GregorianCalendar object construction.
182 * Returns U_ZERO_ERROR if constructed successfully.
183 * @stable ICU 2.0
184 */
185 GregorianCalendar(TimeZone* zoneToAdopt, UErrorCode& success);
186
187 /**
188 * Constructs a GregorianCalendar based on the current time in the given time zone
189 * with the default locale.
190 *
191 * @param zone The given timezone.
192 * @param success Indicates the status of GregorianCalendar object construction.
193 * Returns U_ZERO_ERROR if constructed successfully.
194 * @stable ICU 2.0
195 */
196 GregorianCalendar(const TimeZone& zone, UErrorCode& success);
197
198 /**
199 * Constructs a GregorianCalendar based on the current time in the default time zone
200 * with the given locale.
201 *
202 * @param aLocale The given locale.
203 * @param success Indicates the status of GregorianCalendar object construction.
204 * Returns U_ZERO_ERROR if constructed successfully.
205 * @stable ICU 2.0
206 */
207 GregorianCalendar(const Locale& aLocale, UErrorCode& success);
208
209 /**
210 * Constructs a GregorianCalendar based on the current time in the given time zone
211 * with the given locale. Clients are no longer responsible for deleting the given
212 * time zone object after it's adopted.
213 *
214 * @param zoneToAdopt The given timezone.
215 * @param aLocale The given locale.
216 * @param success Indicates the status of GregorianCalendar object construction.
217 * Returns U_ZERO_ERROR if constructed successfully.
218 * @stable ICU 2.0
219 */
220 GregorianCalendar(TimeZone* zoneToAdopt, const Locale& aLocale, UErrorCode& success);
221
222 /**
223 * Constructs a GregorianCalendar based on the current time in the given time zone
224 * with the given locale.
225 *
226 * @param zone The given timezone.
227 * @param aLocale The given locale.
228 * @param success Indicates the status of GregorianCalendar object construction.
229 * Returns U_ZERO_ERROR if constructed successfully.
230 * @stable ICU 2.0
231 */
232 GregorianCalendar(const TimeZone& zone, const Locale& aLocale, UErrorCode& success);
233
234 /**
235 * Constructs a GregorianCalendar with the given AD date set in the default time
236 * zone with the default locale.
237 *
238 * @param year The value used to set the YEAR time field in the calendar.
239 * @param month The value used to set the MONTH time field in the calendar. Month
240 * value is 0-based. e.g., 0 for January.
241 * @param date The value used to set the DATE time field in the calendar.
242 * @param success Indicates the status of GregorianCalendar object construction.
243 * Returns U_ZERO_ERROR if constructed successfully.
244 * @stable ICU 2.0
245 */
246 GregorianCalendar(int32_t year, int32_t month, int32_t date, UErrorCode& success);
247
248 /**
249 * Constructs a GregorianCalendar with the given AD date and time set for the
250 * default time zone with the default locale.
251 *
252 * @param year The value used to set the YEAR time field in the calendar.
253 * @param month The value used to set the MONTH time field in the calendar. Month
254 * value is 0-based. e.g., 0 for January.
255 * @param date The value used to set the DATE time field in the calendar.
256 * @param hour The value used to set the HOUR_OF_DAY time field in the calendar.
257 * @param minute The value used to set the MINUTE time field in the calendar.
258 * @param success Indicates the status of GregorianCalendar object construction.
259 * Returns U_ZERO_ERROR if constructed successfully.
260 * @stable ICU 2.0
261 */
262 GregorianCalendar(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, UErrorCode& success);
263
264 /**
265 * Constructs a GregorianCalendar with the given AD date and time set for the
266 * default time zone with the default locale.
267 *
268 * @param year The value used to set the YEAR time field in the calendar.
269 * @param month The value used to set the MONTH time field in the calendar. Month
270 * value is 0-based. e.g., 0 for January.
271 * @param date The value used to set the DATE time field in the calendar.
272 * @param hour The value used to set the HOUR_OF_DAY time field in the calendar.
273 * @param minute The value used to set the MINUTE time field in the calendar.
274 * @param second The value used to set the SECOND time field in the calendar.
275 * @param success Indicates the status of GregorianCalendar object construction.
276 * Returns U_ZERO_ERROR if constructed successfully.
277 * @stable ICU 2.0
278 */
279 GregorianCalendar(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, int32_t second, UErrorCode& success);
280
281 /**
282 * Destructor
283 * @stable ICU 2.0
284 */
285 virtual ~GregorianCalendar();
286
287 /**
288 * Copy constructor
289 * @param source the object to be copied.
290 * @stable ICU 2.0
291 */
292 GregorianCalendar(const GregorianCalendar& source);
293
294 /**
295 * Default assignment operator
296 * @param right the object to be copied.
297 * @stable ICU 2.0
298 */
299 GregorianCalendar& operator=(const GregorianCalendar& right);
300
301 /**
302 * Create and return a polymorphic copy of this calendar.
303 * @return return a polymorphic copy of this calendar.
304 * @stable ICU 2.0
305 */
306 virtual GregorianCalendar* clone() const override;
307
308 /**
309 * Sets the GregorianCalendar change date. This is the point when the switch from
310 * Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October
311 * 15, 1582. Previous to this time and date will be Julian dates.
312 *
313 * @param date The given Gregorian cutover date.
314 * @param success Output param set to success/failure code on exit.
315 * @stable ICU 2.0
316 */
317 void setGregorianChange(UDate date, UErrorCode& success);
318
319 /**
320 * Gets the Gregorian Calendar change date. This is the point when the switch from
321 * Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October
322 * 15, 1582. Previous to this time and date will be Julian dates.
323 *
324 * @return The Gregorian cutover time for this calendar.
325 * @stable ICU 2.0
326 */
327 UDate getGregorianChange(void) const;
328
329 /**
330 * Return true if the given year is a leap year. Determination of whether a year is
331 * a leap year is actually very complicated. We do something crude and mostly
332 * correct here, but for a real determination you need a lot of contextual
333 * information. For example, in Sweden, the change from Julian to Gregorian happened
334 * in a complex way resulting in missed leap years and double leap years between
335 * 1700 and 1753. Another example is that after the start of the Julian calendar in
336 * 45 B.C., the leap years did not regularize until 8 A.D. This method ignores these
337 * quirks, and pays attention only to the Julian onset date and the Gregorian
338 * cutover (which can be changed).
339 *
340 * @param year The given year.
341 * @return True if the given year is a leap year; false otherwise.
342 * @stable ICU 2.0
343 */
344 UBool isLeapYear(int32_t year) const;
345
346 /**
347 * Returns true if the given Calendar object is equivalent to this
348 * one. Calendar override.
349 *
350 * @param other the Calendar to be compared with this Calendar
351 * @stable ICU 2.4
352 */
353 virtual UBool isEquivalentTo(const Calendar& other) const override;
354
355#ifndef U_FORCE_HIDE_DEPRECATED_API
356 /**
357 * (Overrides Calendar) Rolls up or down by the given amount in the specified field.
358 * For more information, see the documentation for Calendar::roll().
359 *
360 * @param field The time field.
361 * @param amount Indicates amount to roll.
362 * @param status Output param set to success/failure code on exit. If any value
363 * previously set in the time field is invalid, this will be set to
364 * an error status.
365 * @deprecated ICU 2.6. Use roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) instead.
366 */
367 virtual void roll(EDateFields field, int32_t amount, UErrorCode& status) override;
368#endif // U_FORCE_HIDE_DEPRECATED_API
369
370 /**
371 * (Overrides Calendar) Rolls up or down by the given amount in the specified field.
372 * For more information, see the documentation for Calendar::roll().
373 *
374 * @param field The time field.
375 * @param amount Indicates amount to roll.
376 * @param status Output param set to success/failure code on exit. If any value
377 * previously set in the time field is invalid, this will be set to
378 * an error status.
379 * @stable ICU 2.6.
380 */
381 virtual void roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) override;
382
383#ifndef U_HIDE_DEPRECATED_API
384 /**
385 * Return the minimum value that this field could have, given the current date.
386 * For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
387 * @param field the time field.
388 * @return the minimum value that this field could have, given the current date.
389 * @deprecated ICU 2.6. Use getActualMinimum(UCalendarDateFields field) instead.
390 */
391 int32_t getActualMinimum(EDateFields field) const;
392
393 /**
394 * Return the minimum value that this field could have, given the current date.
395 * For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
396 * @param field the time field.
397 * @param status
398 * @return the minimum value that this field could have, given the current date.
399 * @deprecated ICU 2.6. Use getActualMinimum(UCalendarDateFields field) instead. (Added to ICU 3.0 for signature consistency)
400 */
401 int32_t getActualMinimum(EDateFields field, UErrorCode& status) const;
402#endif /* U_HIDE_DEPRECATED_API */
403
404 /**
405 * Return the minimum value that this field could have, given the current date.
406 * For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
407 * @param field the time field.
408 * @param status error result.
409 * @return the minimum value that this field could have, given the current date.
410 * @stable ICU 3.0
411 */
412 int32_t getActualMinimum(UCalendarDateFields field, UErrorCode &status) const override;
413
414#ifndef U_HIDE_DEPRECATED_API
415 /**
416 * Return the maximum value that this field could have, given the current date.
417 * For example, with the date "Feb 3, 1997" and the DAY_OF_MONTH field, the actual
418 * maximum would be 28; for "Feb 3, 1996" it s 29. Similarly for a Hebrew calendar,
419 * for some years the actual maximum for MONTH is 12, and for others 13.
420 * @param field the time field.
421 * @return the maximum value that this field could have, given the current date.
422 * @deprecated ICU 2.6. Use getActualMaximum(UCalendarDateFields field) instead.
423 */
424 int32_t getActualMaximum(EDateFields field) const;
425#endif /* U_HIDE_DEPRECATED_API */
426
427 /**
428 * Return the maximum value that this field could have, given the current date.
429 * For example, with the date "Feb 3, 1997" and the DAY_OF_MONTH field, the actual
430 * maximum would be 28; for "Feb 3, 1996" it s 29. Similarly for a Hebrew calendar,
431 * for some years the actual maximum for MONTH is 12, and for others 13.
432 * @param field the time field.
433 * @param status returns any errors that may result from this function call.
434 * @return the maximum value that this field could have, given the current date.
435 * @stable ICU 2.6
436 */
437 virtual int32_t getActualMaximum(UCalendarDateFields field, UErrorCode& status) const override;
438
439 /**
440 * (Overrides Calendar) Return true if the current date for this Calendar is in
441 * Daylight Savings Time. Recognizes DST_OFFSET, if it is set.
442 *
443 * @param status Fill-in parameter which receives the status of this operation.
444 * @return True if the current date for this Calendar is in Daylight Savings Time,
445 * false, otherwise.
446 * @stable ICU 2.0
447 */
448 virtual UBool inDaylightTime(UErrorCode& status) const override;
449
450public:
451
452 /**
453 * Override Calendar Returns a unique class ID POLYMORPHICALLY. Pure virtual
454 * override. This method is to implement a simple version of RTTI, since not all C++
455 * compilers support genuine RTTI. Polymorphic operator==() and clone() methods call
456 * this method.
457 *
458 * @return The class ID for this object. All objects of a given class have the
459 * same class ID. Objects of other classes have different class IDs.
460 * @stable ICU 2.0
461 */
462 virtual UClassID getDynamicClassID(void) const override;
463
464 /**
465 * Return the class ID for this class. This is useful only for comparing to a return
466 * value from getDynamicClassID(). For example:
467 *
468 * Base* polymorphic_pointer = createPolymorphicObject();
469 * if (polymorphic_pointer->getDynamicClassID() ==
470 * Derived::getStaticClassID()) ...
471 *
472 * @return The class ID for all objects of this class.
473 * @stable ICU 2.0
474 */
475 static UClassID U_EXPORT2 getStaticClassID(void);
476
477 /**
478 * Returns the calendar type name string for this Calendar object.
479 * The returned string is the legacy ICU calendar attribute value,
480 * for example, "gregorian" or "japanese".
481 *
482 * For more details see the Calendar::getType() documentation.
483 *
484 * @return legacy calendar type name string
485 * @stable ICU 49
486 */
487 virtual const char * getType() const override;
488
489 private:
490 GregorianCalendar(); // default constructor not implemented
491
492 protected:
493 /**
494 * Return the ERA. We need a special method for this because the
495 * default ERA is AD, but a zero (unset) ERA is BC.
496 * @return the ERA.
497 * @internal
498 */
499 virtual int32_t internalGetEra() const;
500
501 /**
502 * Return the Julian day number of day before the first day of the
503 * given month in the given extended year. Subclasses should override
504 * this method to implement their calendar system.
505 * @param eyear the extended year
506 * @param month the zero-based month, or 0 if useMonth is false
507 * @param useMonth if false, compute the day before the first day of
508 * the given year, otherwise, compute the day before the first day of
509 * the given month
510 * @return the Julian day number of the day before the first
511 * day of the given month and year
512 * @internal
513 */
514 virtual int32_t handleComputeMonthStart(int32_t eyear, int32_t month,
515 UBool useMonth) const override;
516
517 /**
518 * Subclasses may override this. This method calls
519 * handleGetMonthLength() to obtain the calendar-specific month
520 * length.
521 * @param bestField which field to use to calculate the date
522 * @return julian day specified by calendar fields.
523 * @internal
524 */
525 virtual int32_t handleComputeJulianDay(UCalendarDateFields bestField) override;
526
527 /**
528 * Return the number of days in the given month of the given extended
529 * year of this calendar system. Subclasses should override this
530 * method if they can provide a more correct or more efficient
531 * implementation than the default implementation in Calendar.
532 * @internal
533 */
534 virtual int32_t handleGetMonthLength(int32_t extendedYear, int32_t month) const override;
535
536 /**
537 * Return the number of days in the given extended year of this
538 * calendar system. Subclasses should override this method if they can
539 * provide a more correct or more efficient implementation than the
540 * default implementation in Calendar.
541 * @stable ICU 2.0
542 */
543 virtual int32_t handleGetYearLength(int32_t eyear) const override;
544
545 /**
546 * return the length of the given month.
547 * @param month the given month.
548 * @return the length of the given month.
549 * @internal
550 */
551 virtual int32_t monthLength(int32_t month) const;
552
553 /**
554 * return the length of the month according to the given year.
555 * @param month the given month.
556 * @param year the given year.
557 * @return the length of the month
558 * @internal
559 */
560 virtual int32_t monthLength(int32_t month, int32_t year) const;
561
562#ifndef U_HIDE_INTERNAL_API
563 /**
564 * return the length of the given year.
565 * @param year the given year.
566 * @return the length of the given year.
567 * @internal
568 */
569 int32_t yearLength(int32_t year) const;
570
571 /**
572 * return the length of the year field.
573 * @return the length of the year field
574 * @internal
575 */
576 int32_t yearLength(void) const;
577
578 /**
579 * After adjustments such as add(MONTH), add(YEAR), we don't want the
580 * month to jump around. E.g., we don't want Jan 31 + 1 month to go to Mar
581 * 3, we want it to go to Feb 28. Adjustments which might run into this
582 * problem call this method to retain the proper month.
583 * @internal
584 */
585 void pinDayOfMonth(void);
586#endif /* U_HIDE_INTERNAL_API */
587
588 /**
589 * Return the day number with respect to the epoch. January 1, 1970 (Gregorian)
590 * is day zero.
591 * @param status Fill-in parameter which receives the status of this operation.
592 * @return the day number with respect to the epoch.
593 * @internal
594 */
595 virtual UDate getEpochDay(UErrorCode& status);
596
597 /**
598 * Subclass API for defining limits of different types.
599 * Subclasses must implement this method to return limits for the
600 * following fields:
601 *
602 * <pre>UCAL_ERA
603 * UCAL_YEAR
604 * UCAL_MONTH
605 * UCAL_WEEK_OF_YEAR
606 * UCAL_WEEK_OF_MONTH
607 * UCAL_DATE (DAY_OF_MONTH on Java)
608 * UCAL_DAY_OF_YEAR
609 * UCAL_DAY_OF_WEEK_IN_MONTH
610 * UCAL_YEAR_WOY
611 * UCAL_EXTENDED_YEAR</pre>
612 *
613 * @param field one of the above field numbers
614 * @param limitType one of <code>MINIMUM</code>, <code>GREATEST_MINIMUM</code>,
615 * <code>LEAST_MAXIMUM</code>, or <code>MAXIMUM</code>
616 * @internal
617 */
618 virtual int32_t handleGetLimit(UCalendarDateFields field, ELimitType limitType) const override;
619
620 /**
621 * Return the extended year defined by the current fields. This will
622 * use the UCAL_EXTENDED_YEAR field or the UCAL_YEAR and supra-year fields (such
623 * as UCAL_ERA) specific to the calendar system, depending on which set of
624 * fields is newer.
625 * @return the extended year
626 * @internal
627 */
628 virtual int32_t handleGetExtendedYear() override;
629
630 /**
631 * Subclasses may override this to convert from week fields
632 * (YEAR_WOY and WEEK_OF_YEAR) to an extended year in the case
633 * where YEAR, EXTENDED_YEAR are not set.
634 * The Gregorian implementation assumes a yearWoy in gregorian format, according to the current era.
635 * @return the extended year, UCAL_EXTENDED_YEAR
636 * @internal
637 */
638 virtual int32_t handleGetExtendedYearFromWeekFields(int32_t yearWoy, int32_t woy) override;
639
640
641 /**
642 * Subclasses may override this method to compute several fields
643 * specific to each calendar system. These are:
644 *
645 * <ul><li>ERA
646 * <li>YEAR
647 * <li>MONTH
648 * <li>DAY_OF_MONTH
649 * <li>DAY_OF_YEAR
650 * <li>EXTENDED_YEAR</ul>
651 *
652 * <p>The GregorianCalendar implementation implements
653 * a calendar with the specified Julian/Gregorian cutover date.
654 * @internal
655 */
656 virtual void handleComputeFields(int32_t julianDay, UErrorCode &status) override;
657
658 private:
659 /**
660 * Compute the julian day number of the given year.
661 * @param isGregorian if true, using Gregorian calendar, otherwise using Julian calendar
662 * @param year the given year.
663 * @param isLeap true if the year is a leap year.
664 * @return
665 */
666 static double computeJulianDayOfYear(UBool isGregorian, int32_t year,
667 UBool& isLeap);
668
669 /**
670 * Validates the values of the set time fields. True if they're all valid.
671 * @return True if the set time fields are all valid.
672 */
673 UBool validateFields(void) const;
674
675 /**
676 * Validates the value of the given time field. True if it's valid.
677 */
678 UBool boundsCheck(int32_t value, UCalendarDateFields field) const;
679
680 /**
681 * Return the pseudo-time-stamp for two fields, given their
682 * individual pseudo-time-stamps. If either of the fields
683 * is unset, then the aggregate is unset. Otherwise, the
684 * aggregate is the later of the two stamps.
685 * @param stamp_a One given field.
686 * @param stamp_b Another given field.
687 * @return the pseudo-time-stamp for two fields
688 */
689 int32_t aggregateStamp(int32_t stamp_a, int32_t stamp_b);
690
691 /**
692 * The point at which the Gregorian calendar rules are used, measured in
693 * milliseconds from the standard epoch. Default is October 15, 1582
694 * (Gregorian) 00:00:00 UTC, that is, October 4, 1582 (Julian) is followed
695 * by October 15, 1582 (Gregorian). This corresponds to Julian day number
696 * 2299161. This is measured from the standard epoch, not in Julian Days.
697 */
698 UDate fGregorianCutover;
699
700 /**
701 * Julian day number of the Gregorian cutover
702 */
703 int32_t fCutoverJulianDay;
704
705 /**
706 * Midnight, local time (using this Calendar's TimeZone) at or before the
707 * gregorianCutover. This is a pure date value with no time of day or
708 * timezone component.
709 */
710 UDate fNormalizedGregorianCutover;// = gregorianCutover;
711
712 /**
713 * The year of the gregorianCutover, with 0 representing
714 * 1 BC, -1 representing 2 BC, etc.
715 */
716 int32_t fGregorianCutoverYear;// = 1582;
717
718 /**
719 * The year of the gregorianCutover, with 0 representing
720 * 1 BC, -1 representing 2 BC, etc.
721 */
722 int32_t fGregorianCutoverJulianDay;// = 2299161;
723
724 /**
725 * Converts time as milliseconds to Julian date. The Julian date used here is not a
726 * true Julian date, since it is measured from midnight, not noon.
727 *
728 * @param millis The given milliseconds.
729 * @return The Julian date number.
730 */
731 static double millisToJulianDay(UDate millis);
732
733 /**
734 * Converts Julian date to time as milliseconds. The Julian date used here is not a
735 * true Julian date, since it is measured from midnight, not noon.
736 *
737 * @param julian The given Julian date number.
738 * @return Time as milliseconds.
739 */
740 static UDate julianDayToMillis(double julian);
741
742 /**
743 * Used by handleComputeJulianDay() and handleComputeMonthStart().
744 * Temporary field indicating whether the calendar is currently Gregorian as opposed to Julian.
745 */
746 UBool fIsGregorian;
747
748 /**
749 * Used by handleComputeJulianDay() and handleComputeMonthStart().
750 * Temporary field indicating that the sense of the gregorian cutover should be inverted
751 * to handle certain calculations on and around the cutover date.
752 */
753 UBool fInvertGregorian;
754
755
756 public: // internal implementation
757
758 /**
759 * @return true if this calendar has the notion of a default century
760 * @internal
761 */
762 virtual UBool haveDefaultCentury() const override;
763
764 /**
765 * @return the start of the default century
766 * @internal
767 */
768 virtual UDate defaultCenturyStart() const override;
769
770 /**
771 * @return the beginning year of the default century
772 * @internal
773 */
774 virtual int32_t defaultCenturyStartYear() const override;
775};
776
777U_NAMESPACE_END
778
779#endif /* #if !UCONFIG_NO_FORMATTING */
780
781#endif /* U_SHOW_CPLUSPLUS_API */
782
783#endif // _GREGOCAL
784//eof
785
786

source code of include/unicode/gregocal.h