1	// © 2016 and later: Unicode, Inc. and others.
2	// License & terms of use: http://www.unicode.org/copyright.html
3	/*
4	********************************************************************************
5	* Copyright (C) 1997-2014, International Business Machines
6	* Corporation and others. All Rights Reserved.
7	********************************************************************************
8	*
9	* File CALENDAR.H
10	*
11	* Modification History:
12	*
13	* Date Name Description
14	* 04/22/97 aliu Expanded and corrected comments and other header
15	* contents.
16	* 05/01/97 aliu Made equals(), before(), after() arguments const.
17	* 05/20/97 aliu Replaced fAreFieldsSet with fAreFieldsInSync and
18	* fAreAllFieldsSet.
19	* 07/27/98 stephen Sync up with JDK 1.2
20	* 11/15/99 weiv added YEAR_WOY and DOW_LOCAL
21	* to EDateFields
22	* 8/19/2002 srl Removed Javaisms
23	* 11/07/2003 srl Update, clean up documentation.
24	********************************************************************************
25	*/
26
27	#ifndef CALENDAR_H
28	#define CALENDAR_H
29
30	#include "unicode/utypes.h"
31
32	#if U_SHOW_CPLUSPLUS_API
33
34	/**
35	* \file
36	* \brief C++ API: Calendar object
37	*/
38	#if !UCONFIG_NO_FORMATTING
39
40	#include "unicode/uobject.h"
41	#include "unicode/locid.h"
42	#include "unicode/timezone.h"
43	#include "unicode/ucal.h"
44	#include "unicode/umisc.h"
45
46	U_NAMESPACE_BEGIN
47
48	class ICUServiceFactory;
49
50	// Do not conditionalize the following with #ifndef U_HIDE_INTERNAL_API,
51	// it is a return type for a virtual method (@internal)
52	/**
53	* @internal
54	*/
55	typedef int32_t UFieldResolutionTable[12][8];
56
57	class BasicTimeZone;
58	/**
59	* `Calendar` is an abstract base class for converting between
60	* a `UDate` object and a set of integer fields such as
61	* `YEAR`, `MONTH`, `DAY`, `HOUR`, and so on.
62	* (A `UDate` object represents a specific instant in
63	* time with millisecond precision. See UDate
64	* for information about the `UDate` class.)
65	*
66	* Subclasses of `Calendar` interpret a `UDate`
67	* according to the rules of a specific calendar system.
68	* The most commonly used subclass of `Calendar` is
69	* `GregorianCalendar`. Other subclasses could represent
70	* the various types of lunar calendars in use in many parts of the world.
71	*
72	* **NOTE**: (ICU 2.6) The subclass interface should be considered unstable -
73	* it WILL change.
74	*
75	* Like other locale-sensitive classes, `Calendar` provides a
76	* static method, `createInstance`, for getting a generally useful
77	* object of this type. `Calendar`'s `createInstance` method
78	* returns the appropriate `Calendar` subclass whose
79	* time fields have been initialized with the current date and time:
80	*
81	* Calendar *rightNow = Calendar::createInstance(errCode);
82	*
83	* A `Calendar` object can produce all the time field values
84	* needed to implement the date-time formatting for a particular language
85	* and calendar style (for example, Japanese-Gregorian, Japanese-Traditional).
86	*
87	* When computing a `UDate` from time fields, some special circumstances
88	* may arise: there may be insufficient information to compute the
89	* `UDate` (such as only year and month but no day in the month),
90	* there may be inconsistent information (such as "Tuesday, July 15, 1996"
91	* -- July 15, 1996 is actually a Monday), or the input time might be ambiguous
92	* because of time zone transition.
93	*
94	* **Insufficient information.** The calendar will use default
95	* information to specify the missing fields. This may vary by calendar; for
96	* the Gregorian calendar, the default for a field is the same as that of the
97	* start of the epoch: i.e., YEAR = 1970, MONTH = JANUARY, DATE = 1, etc.
98	*
99	* **Inconsistent information.** If fields conflict, the calendar
100	* will give preference to fields set more recently. For example, when
101	* determining the day, the calendar will look for one of the following
102	* combinations of fields. The most recent combination, as determined by the
103	* most recently set single field, will be used.
104	*
105	* MONTH + DAY_OF_MONTH
106	* MONTH + WEEK_OF_MONTH + DAY_OF_WEEK
107	* MONTH + DAY_OF_WEEK_IN_MONTH + DAY_OF_WEEK
108	* DAY_OF_YEAR
109	* DAY_OF_WEEK + WEEK_OF_YEAR
110	*
111	* For the time of day:
112	*
113	* HOUR_OF_DAY
114	* AM_PM + HOUR
115	*
116	* **Ambiguous Wall Clock Time.** When time offset from UTC has
117	* changed, it produces an ambiguous time slot around the transition. For example,
118	* many US locations observe daylight saving time. On the date switching to daylight
119	* saving time in US, wall clock time jumps from 12:59 AM (standard) to 2:00 AM
120	* (daylight). Therefore, wall clock time from 1:00 AM to 1:59 AM do not exist on
121	* the date. When the input wall time fall into this missing time slot, the ICU
122	* Calendar resolves the time using the UTC offset before the transition by default.
123	* In this example, 1:30 AM is interpreted as 1:30 AM standard time (non-exist),
124	* so the final result will be 2:30 AM daylight time.
125	*
126	* On the date switching back to standard time, wall clock time is moved back one
127	* hour at 2:00 AM. So wall clock time from 1:00 AM to 1:59 AM occur twice. In this
128	* case, the ICU Calendar resolves the time using the UTC offset after the transition
129	* by default. For example, 1:30 AM on the date is resolved as 1:30 AM standard time.
130	*
131	* Ambiguous wall clock time resolution behaviors can be customized by Calendar APIs
132	* {@link #setRepeatedWallTimeOption} and {@link #setSkippedWallTimeOption}.
133	* These methods are available in ICU 49 or later versions.
134	*
135	* **Note:** for some non-Gregorian calendars, different
136	* fields may be necessary for complete disambiguation. For example, a full
137	* specification of the historical Arabic astronomical calendar requires year,
138	* month, day-of-month *and* day-of-week in some cases.
139	*
140	* **Note:** There are certain possible ambiguities in
141	* interpretation of certain singular times, which are resolved in the
142	* following ways:
143	*
144	* 1. 24:00:00 "belongs" to the following day. That is,
145	* 23:59 on Dec 31, 1969 < 24:00 on Jan 1, 1970 < 24:01:00 on Jan 1, 1970
146	* 2. Although historically not precise, midnight also belongs to "am",
147	* and noon belongs to "pm", so on the same day,
148	* 12:00 am (midnight) < 12:01 am, and 12:00 pm (noon) < 12:01 pm
149	*
150	* The date or time format strings are not part of the definition of a
151	* calendar, as those must be modifiable or overridable by the user at
152	* runtime. Use `DateFormat` to format dates.
153	*
154	* `Calendar` provides an API for field "rolling", where fields
155	* can be incremented or decremented, but wrap around. For example, rolling the
156	* month up in the date December 12, **1996** results in
157	* January 12, **1996**.
158	*
159	* `Calendar` also provides a date arithmetic function for
160	* adding the specified (signed) amount of time to a particular time field.
161	* For example, subtracting 5 days from the date `September 12, 1996`
162	* results in `September 7, 1996`.
163	*
164	* ***Supported range***
165	*
166	* The allowable range of `Calendar` has been narrowed. `GregorianCalendar` used
167	* to attempt to support the range of dates with millisecond values from
168	* `Long.MIN_VALUE` to `Long.MAX_VALUE`. The new `Calendar` protocol specifies the
169	* maximum range of supportable dates as those having Julian day numbers
170	* of `-0x7F000000` to `+0x7F000000`. This corresponds to years from ~5,800,000 BCE
171	* to ~5,800,000 CE. Programmers should use the protected constants in `Calendar` to
172	* specify an extremely early or extremely late date.
173	*
174	* <p>
175	* The Japanese calendar uses a combination of era name and year number.
176	* When an emperor of Japan abdicates and a new emperor ascends the throne,
177	* a new era is declared and year number is reset to 1. Even if the date of
178	* abdication is scheduled ahead of time, the new era name might not be
179	* announced until just before the date. In such case, ICU4C may include
180	* a start date of future era without actual era name, but not enabled
181	* by default. ICU4C users who want to test the behavior of the future era
182	* can enable the tentative era by:
183	* <ul>
184	* <li>Environment variable <code>ICU_ENABLE_TENTATIVE_ERA=true</code>.</li>
185	* </ul>
186	*
187	* @stable ICU 2.0
188	*/
189	class U_I18N_API Calendar : public UObject {
190	public:
191	#ifndef U_FORCE_HIDE_DEPRECATED_API
192	/**
193	* Field IDs for date and time. Used to specify date/time fields. ERA is calendar
194	* specific. Example ranges given are for illustration only; see specific Calendar
195	* subclasses for actual ranges.
196	* @deprecated ICU 2.6. Use C enum UCalendarDateFields defined in ucal.h
197	*/
198	enum EDateFields {
199	#ifndef U_HIDE_DEPRECATED_API
200	/*
201	* ERA may be defined on other platforms. To avoid any potential problems undefined it here.
202	*/
203	#ifdef ERA
204	#undef ERA
205	#endif
206	ERA, // Example: 0..1
207	YEAR, // Example: 1..big number
208	MONTH, // Example: 0..11
209	WEEK_OF_YEAR, // Example: 1..53
210	WEEK_OF_MONTH, // Example: 1..4
211	DATE, // Example: 1..31
212	DAY_OF_YEAR, // Example: 1..365
213	DAY_OF_WEEK, // Example: 1..7
214	DAY_OF_WEEK_IN_MONTH, // Example: 1..4, may be specified as -1
215	AM_PM, // Example: 0..1
216	HOUR, // Example: 0..11
217	HOUR_OF_DAY, // Example: 0..23
218	MINUTE, // Example: 0..59
219	SECOND, // Example: 0..59
220	MILLISECOND, // Example: 0..999
221	ZONE_OFFSET, // Example: -12*U_MILLIS_PER_HOUR..12*U_MILLIS_PER_HOUR
222	DST_OFFSET, // Example: 0 or U_MILLIS_PER_HOUR
223	YEAR_WOY, // 'Y' Example: 1..big number - Year of Week of Year
224	DOW_LOCAL, // 'e' Example: 1..7 - Day of Week / Localized
225
226	EXTENDED_YEAR,
227	JULIAN_DAY,
228	MILLISECONDS_IN_DAY,
229	IS_LEAP_MONTH,
230
231	FIELD_COUNT = UCAL_FIELD_COUNT // See ucal.h for other fields.
232	#endif /* U_HIDE_DEPRECATED_API */
233	};
234	#endif // U_FORCE_HIDE_DEPRECATED_API
235
236	#ifndef U_HIDE_DEPRECATED_API
237	/**
238	* Useful constant for days of week. Note: Calendar day-of-week is 1-based. Clients
239	* who create locale resources for the field of first-day-of-week should be aware of
240	* this. For instance, in US locale, first-day-of-week is set to 1, i.e., SUNDAY.
241	* @deprecated ICU 2.6. Use C enum UCalendarDaysOfWeek defined in ucal.h
242	*/
243	enum EDaysOfWeek {
244	SUNDAY = 1,
245	MONDAY,
246	TUESDAY,
247	WEDNESDAY,
248	THURSDAY,
249	FRIDAY,
250	SATURDAY
251	};
252
253	/**
254	* Useful constants for month. Note: Calendar month is 0-based.
255	* @deprecated ICU 2.6. Use C enum UCalendarMonths defined in ucal.h
256	*/
257	enum EMonths {
258	JANUARY,
259	FEBRUARY,
260	MARCH,
261	APRIL,
262	MAY,
263	JUNE,
264	JULY,
265	AUGUST,
266	SEPTEMBER,
267	OCTOBER,
268	NOVEMBER,
269	DECEMBER,
270	UNDECIMBER
271	};
272
273	/**
274	* Useful constants for hour in 12-hour clock. Used in GregorianCalendar.
275	* @deprecated ICU 2.6. Use C enum UCalendarAMPMs defined in ucal.h
276	*/
277	enum EAmpm {
278	AM,
279	PM
280	};
281	#endif /* U_HIDE_DEPRECATED_API */
282
283	/**
284	* destructor
285	* @stable ICU 2.0
286	*/
287	virtual ~Calendar();
288
289	/**
290	* Create and return a polymorphic copy of this calendar.
291	*
292	* @return a polymorphic copy of this calendar.
293	* @stable ICU 2.0
294	*/
295	virtual Calendar* clone() const = 0;
296
297	/**
298	* Creates a Calendar using the default timezone and locale. Clients are responsible
299	* for deleting the object returned.
300	*
301	* @param success Indicates the success/failure of Calendar creation. Filled in
302	* with U_ZERO_ERROR if created successfully, set to a failure result
303	* otherwise. U_MISSING_RESOURCE_ERROR will be returned if the resource data
304	* requests a calendar type which has not been installed.
305	* @return A Calendar if created successfully. NULL otherwise.
306	* @stable ICU 2.0
307	*/
308	static Calendar* U_EXPORT2 createInstance(UErrorCode& success);
309
310	/**
311	* Creates a Calendar using the given timezone and the default locale.
312	* The Calendar takes ownership of zoneToAdopt; the
313	* client must not delete it.
314	*
315	* @param zoneToAdopt The given timezone to be adopted.
316	* @param success Indicates the success/failure of Calendar creation. Filled in
317	* with U_ZERO_ERROR if created successfully, set to a failure result
318	* otherwise.
319	* @return A Calendar if created successfully. NULL otherwise.
320	* @stable ICU 2.0
321	*/
322	static Calendar* U_EXPORT2 createInstance(TimeZone* zoneToAdopt, UErrorCode& success);
323
324	/**
325	* Creates a Calendar using the given timezone and the default locale. The TimeZone
326	* is _not_ adopted; the client is still responsible for deleting it.
327	*
328	* @param zone The timezone.
329	* @param success Indicates the success/failure of Calendar creation. Filled in
330	* with U_ZERO_ERROR if created successfully, set to a failure result
331	* otherwise.
332	* @return A Calendar if created successfully. NULL otherwise.
333	* @stable ICU 2.0
334	*/
335	static Calendar* U_EXPORT2 createInstance(const TimeZone& zone, UErrorCode& success);
336
337	/**
338	* Creates a Calendar using the default timezone and the given locale.
339	*
340	* @param aLocale The given locale.
341	* @param success Indicates the success/failure of Calendar creation. Filled in
342	* with U_ZERO_ERROR if created successfully, set to a failure result
343	* otherwise.
344	* @return A Calendar if created successfully. NULL otherwise.
345	* @stable ICU 2.0
346	*/
347	static Calendar* U_EXPORT2 createInstance(const Locale& aLocale, UErrorCode& success);
348
349	/**
350	* Creates a Calendar using the given timezone and given locale.
351	* The Calendar takes ownership of zoneToAdopt; the
352	* client must not delete it.
353	*
354	* @param zoneToAdopt The given timezone to be adopted.
355	* @param aLocale The given locale.
356	* @param success Indicates the success/failure of Calendar creation. Filled in
357	* with U_ZERO_ERROR if created successfully, set to a failure result
358	* otherwise.
359	* @return A Calendar if created successfully. NULL otherwise.
360	* @stable ICU 2.0
361	*/
362	static Calendar* U_EXPORT2 createInstance(TimeZone* zoneToAdopt, const Locale& aLocale, UErrorCode& success);
363
364	/**
365	* Gets a Calendar using the given timezone and given locale. The TimeZone
366	* is _not_ adopted; the client is still responsible for deleting it.
367	*
368	* @param zone The given timezone.
369	* @param aLocale The given locale.
370	* @param success Indicates the success/failure of Calendar creation. Filled in
371	* with U_ZERO_ERROR if created successfully, set to a failure result
372	* otherwise.
373	* @return A Calendar if created successfully. NULL otherwise.
374	* @stable ICU 2.0
375	*/
376	static Calendar* U_EXPORT2 createInstance(const TimeZone& zone, const Locale& aLocale, UErrorCode& success);
377
378	/**
379	* Returns a list of the locales for which Calendars are installed.
380	*
381	* @param count Number of locales returned.
382	* @return An array of Locale objects representing the set of locales for which
383	* Calendars are installed. The system retains ownership of this list;
384	* the caller must NOT delete it. Does not include user-registered Calendars.
385	* @stable ICU 2.0
386	*/
387	static const Locale* U_EXPORT2 getAvailableLocales(int32_t& count);
388
389
390	/**
391	* Given a key and a locale, returns an array of string values in a preferred
392	* order that would make a difference. These are all and only those values where
393	* the open (creation) of the service with the locale formed from the input locale
394	* plus input keyword and that value has different behavior than creation with the
395	* input locale alone.
396	* @param key one of the keys supported by this service. For now, only
397	* "calendar" is supported.
398	* @param locale the locale
399	* @param commonlyUsed if set to true it will return only commonly used values
400	* with the given locale in preferred order. Otherwise,
401	* it will return all the available values for the locale.
402	* @param status ICU Error Code
403	* @return a string enumeration over keyword values for the given key and the locale.
404	* @stable ICU 4.2
405	*/
406	static StringEnumeration* U_EXPORT2 getKeywordValuesForLocale(const char* key,
407	const Locale& locale, UBool commonlyUsed, UErrorCode& status);
408
409	/**
410	* Returns the current UTC (GMT) time measured in milliseconds since 0:00:00 on 1/1/70
411	* (derived from the system time).
412	*
413	* @return The current UTC time in milliseconds.
414	* @stable ICU 2.0
415	*/
416	static UDate U_EXPORT2 getNow(void);
417
418	/**
419	* Gets this Calendar's time as milliseconds. May involve recalculation of time due
420	* to previous calls to set time field values. The time specified is non-local UTC
421	* (GMT) time. Although this method is const, this object may actually be changed
422	* (semantically const).
423	*
424	* @param status Output param set to success/failure code on exit. If any value
425	* previously set in the time field is invalid or restricted by
426	* leniency, this will be set to an error status.
427	* @return The current time in UTC (GMT) time, or zero if the operation
428	* failed.
429	* @stable ICU 2.0
430	*/
431	inline UDate getTime(UErrorCode& status) const { return getTimeInMillis(status); }
432
433	/**
434	* Sets this Calendar's current time with the given UDate. The time specified should
435	* be in non-local UTC (GMT) time.
436	*
437	* @param date The given UDate in UTC (GMT) time.
438	* @param status Output param set to success/failure code on exit. If any value
439	* set in the time field is invalid or restricted by
440	* leniency, this will be set to an error status.
441	* @stable ICU 2.0
442	*/
443	inline void setTime(UDate date, UErrorCode& status) { setTimeInMillis(millis: date, status); }
444
445	/**
446	* Compares the equality of two Calendar objects. Objects of different subclasses
447	* are considered unequal. This comparison is very exacting; two Calendar objects
448	* must be in exactly the same state to be considered equal. To compare based on the
449	* represented time, use equals() instead.
450	*
451	* @param that The Calendar object to be compared with.
452	* @return true if the given Calendar is the same as this Calendar; false
453	* otherwise.
454	* @stable ICU 2.0
455	*/
456	virtual bool operator==(const Calendar& that) const;
457
458	/**
459	* Compares the inequality of two Calendar objects.
460	*
461	* @param that The Calendar object to be compared with.
462	* @return true if the given Calendar is not the same as this Calendar; false
463	* otherwise.
464	* @stable ICU 2.0
465	*/
466	bool operator!=(const Calendar& that) const {return !operator==(that);}
467
468	/**
469	* Returns true if the given Calendar object is equivalent to this
470	* one. An equivalent Calendar will behave exactly as this one
471	* does, but it may be set to a different time. By contrast, for
472	* the operator==() method to return true, the other Calendar must
473	* be set to the same time.
474	*
475	* @param other the Calendar to be compared with this Calendar
476	* @stable ICU 2.4
477	*/
478	virtual UBool isEquivalentTo(const Calendar& other) const;
479
480	/**
481	* Compares the Calendar time, whereas Calendar::operator== compares the equality of
482	* Calendar objects.
483	*
484	* @param when The Calendar to be compared with this Calendar. Although this is a
485	* const parameter, the object may be modified physically
486	* (semantically const).
487	* @param status Output param set to success/failure code on exit. If any value
488	* previously set in the time field is invalid or restricted by
489	* leniency, this will be set to an error status.
490	* @return True if the current time of this Calendar is equal to the time of
491	* Calendar when; false otherwise.
492	* @stable ICU 2.0
493	*/
494	UBool equals(const Calendar& when, UErrorCode& status) const;
495
496	/**
497	* Returns true if this Calendar's current time is before "when"'s current time.
498	*
499	* @param when The Calendar to be compared with this Calendar. Although this is a
500	* const parameter, the object may be modified physically
501	* (semantically const).
502	* @param status Output param set to success/failure code on exit. If any value
503	* previously set in the time field is invalid or restricted by
504	* leniency, this will be set to an error status.
505	* @return True if the current time of this Calendar is before the time of
506	* Calendar when; false otherwise.
507	* @stable ICU 2.0
508	*/
509	UBool before(const Calendar& when, UErrorCode& status) const;
510
511	/**
512	* Returns true if this Calendar's current time is after "when"'s current time.
513	*
514	* @param when The Calendar to be compared with this Calendar. Although this is a
515	* const parameter, the object may be modified physically
516	* (semantically const).
517	* @param status Output param set to success/failure code on exit. If any value
518	* previously set in the time field is invalid or restricted by
519	* leniency, this will be set to an error status.
520	* @return True if the current time of this Calendar is after the time of
521	* Calendar when; false otherwise.
522	* @stable ICU 2.0
523	*/
524	UBool after(const Calendar& when, UErrorCode& status) const;
525
526	#ifndef U_FORCE_HIDE_DEPRECATED_API
527	/**
528	* UDate Arithmetic function. Adds the specified (signed) amount of time to the given
529	* time field, based on the calendar's rules. For example, to subtract 5 days from
530	* the current time of the calendar, call add(Calendar::DATE, -5). When adding on
531	* the month or Calendar::MONTH field, other fields like date might conflict and
532	* need to be changed. For instance, adding 1 month on the date 01/31/96 will result
533	* in 02/29/96.
534	* Adding a positive value always means moving forward in time, so for the Gregorian calendar,
535	* starting with 100 BC and adding +1 to year results in 99 BC (even though this actually reduces
536	* the numeric value of the field itself).
537	*
538	* @param field Specifies which date field to modify.
539	* @param amount The amount of time to be added to the field, in the natural unit
540	* for that field (e.g., days for the day fields, hours for the hour
541	* field.)
542	* @param status Output param set to success/failure code on exit. If any value
543	* previously set in the time field is invalid or restricted by
544	* leniency, this will be set to an error status.
545	* @deprecated ICU 2.6. use add(UCalendarDateFields field, int32_t amount, UErrorCode& status) instead.
546	*/
547	virtual void add(EDateFields field, int32_t amount, UErrorCode& status);
548	#endif // U_FORCE_HIDE_DEPRECATED_API
549
550	/**
551	* UDate Arithmetic function. Adds the specified (signed) amount of time to the given
552	* time field, based on the calendar's rules. For example, to subtract 5 days from
553	* the current time of the calendar, call add(Calendar::DATE, -5). When adding on
554	* the month or Calendar::MONTH field, other fields like date might conflict and
555	* need to be changed. For instance, adding 1 month on the date 01/31/96 will result
556	* in 02/29/96.
557	* Adding a positive value always means moving forward in time, so for the Gregorian calendar,
558	* starting with 100 BC and adding +1 to year results in 99 BC (even though this actually reduces
559	* the numeric value of the field itself).
560	*
561	* @param field Specifies which date field to modify.
562	* @param amount The amount of time to be added to the field, in the natural unit
563	* for that field (e.g., days for the day fields, hours for the hour
564	* field.)
565	* @param status Output param set to success/failure code on exit. If any value
566	* previously set in the time field is invalid or restricted by
567	* leniency, this will be set to an error status.
568	* @stable ICU 2.6.
569	*/
570	virtual void add(UCalendarDateFields field, int32_t amount, UErrorCode& status);
571
572	#ifndef U_HIDE_DEPRECATED_API
573	/**
574	* Time Field Rolling function. Rolls (up/down) a single unit of time on the given
575	* time field. For example, to roll the current date up by one day, call
576	* roll(Calendar::DATE, true). When rolling on the year or Calendar::YEAR field, it
577	* will roll the year value in the range between getMinimum(Calendar::YEAR) and the
578	* value returned by getMaximum(Calendar::YEAR). When rolling on the month or
579	* Calendar::MONTH field, other fields like date might conflict and, need to be
580	* changed. For instance, rolling the month up on the date 01/31/96 will result in
581	* 02/29/96. Rolling up always means rolling forward in time (unless the limit of the
582	* field is reached, in which case it may pin or wrap), so for Gregorian calendar,
583	* starting with 100 BC and rolling the year up results in 99 BC.
584	* When eras have a definite beginning and end (as in the Chinese calendar, or as in
585	* most eras in the Japanese calendar) then rolling the year past either limit of the
586	* era will cause the year to wrap around. When eras only have a limit at one end,
587	* then attempting to roll the year past that limit will result in pinning the year
588	* at that limit. Note that for most calendars in which era 0 years move forward in
589	* time (such as Buddhist, Hebrew, or Islamic), it is possible for add or roll to
590	* result in negative years for era 0 (that is the only way to represent years before
591	* the calendar epoch).
592	* When rolling on the hour-in-day or Calendar::HOUR_OF_DAY field, it will roll the
593	* hour value in the range between 0 and 23, which is zero-based.
594	* <P>
595	* NOTE: Do not use this method -- use roll(EDateFields, int, UErrorCode&) instead.
596	*
597	* @param field The time field.
598	* @param up Indicates if the value of the specified time field is to be rolled
599	* up or rolled down. Use true if rolling up, false otherwise.
600	* @param status Output param set to success/failure code on exit. If any value
601	* previously set in the time field is invalid or restricted by
602	* leniency, this will be set to an error status.
603	* @deprecated ICU 2.6. Use roll(UCalendarDateFields field, UBool up, UErrorCode& status) instead.
604	*/
605	inline void roll(EDateFields field, UBool up, UErrorCode& status);
606	#endif /* U_HIDE_DEPRECATED_API */
607
608	/**
609	* Time Field Rolling function. Rolls (up/down) a single unit of time on the given
610	* time field. For example, to roll the current date up by one day, call
611	* roll(Calendar::DATE, true). When rolling on the year or Calendar::YEAR field, it
612	* will roll the year value in the range between getMinimum(Calendar::YEAR) and the
613	* value returned by getMaximum(Calendar::YEAR). When rolling on the month or
614	* Calendar::MONTH field, other fields like date might conflict and, need to be
615	* changed. For instance, rolling the month up on the date 01/31/96 will result in
616	* 02/29/96. Rolling up always means rolling forward in time (unless the limit of the
617	* field is reached, in which case it may pin or wrap), so for Gregorian calendar,
618	* starting with 100 BC and rolling the year up results in 99 BC.
619	* When eras have a definite beginning and end (as in the Chinese calendar, or as in
620	* most eras in the Japanese calendar) then rolling the year past either limit of the
621	* era will cause the year to wrap around. When eras only have a limit at one end,
622	* then attempting to roll the year past that limit will result in pinning the year
623	* at that limit. Note that for most calendars in which era 0 years move forward in
624	* time (such as Buddhist, Hebrew, or Islamic), it is possible for add or roll to
625	* result in negative years for era 0 (that is the only way to represent years before
626	* the calendar epoch).
627	* When rolling on the hour-in-day or Calendar::HOUR_OF_DAY field, it will roll the
628	* hour value in the range between 0 and 23, which is zero-based.
629	* <P>
630	* NOTE: Do not use this method -- use roll(UCalendarDateFields, int, UErrorCode&) instead.
631	*
632	* @param field The time field.
633	* @param up Indicates if the value of the specified time field is to be rolled
634	* up or rolled down. Use true if rolling up, false otherwise.
635	* @param status Output param set to success/failure code on exit. If any value
636	* previously set in the time field is invalid or restricted by
637	* leniency, this will be set to an error status.
638	* @stable ICU 2.6.
639	*/
640	inline void roll(UCalendarDateFields field, UBool up, UErrorCode& status);
641
642	#ifndef U_FORCE_HIDE_DEPRECATED_API
643	/**
644	* Time Field Rolling function. Rolls by the given amount on the given
645	* time field. For example, to roll the current date up by one day, call
646	* roll(Calendar::DATE, +1, status). When rolling on the month or
647	* Calendar::MONTH field, other fields like date might conflict and, need to be
648	* changed. For instance, rolling the month up on the date 01/31/96 will result in
649	* 02/29/96. Rolling by a positive value always means rolling forward in time (unless
650	* the limit of the field is reached, in which case it may pin or wrap), so for
651	* Gregorian calendar, starting with 100 BC and rolling the year by + 1 results in 99 BC.
652	* When eras have a definite beginning and end (as in the Chinese calendar, or as in
653	* most eras in the Japanese calendar) then rolling the year past either limit of the
654	* era will cause the year to wrap around. When eras only have a limit at one end,
655	* then attempting to roll the year past that limit will result in pinning the year
656	* at that limit. Note that for most calendars in which era 0 years move forward in
657	* time (such as Buddhist, Hebrew, or Islamic), it is possible for add or roll to
658	* result in negative years for era 0 (that is the only way to represent years before
659	* the calendar epoch).
660	* When rolling on the hour-in-day or Calendar::HOUR_OF_DAY field, it will roll the
661	* hour value in the range between 0 and 23, which is zero-based.
662	* <P>
663	* The only difference between roll() and add() is that roll() does not change
664	* the value of more significant fields when it reaches the minimum or maximum
665	* of its range, whereas add() does.
666	*
667	* @param field The time field.
668	* @param amount Indicates amount to roll.
669	* @param status Output param set to success/failure code on exit. If any value
670	* previously set in the time field is invalid, this will be set to
671	* an error status.
672	* @deprecated ICU 2.6. Use roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) instead.
673	*/
674	virtual void roll(EDateFields field, int32_t amount, UErrorCode& status);
675	#endif // U_FORCE_HIDE_DEPRECATED_API
676
677	/**
678	* Time Field Rolling function. Rolls by the given amount on the given
679	* time field. For example, to roll the current date up by one day, call
680	* roll(Calendar::DATE, +1, status). When rolling on the month or
681	* Calendar::MONTH field, other fields like date might conflict and, need to be
682	* changed. For instance, rolling the month up on the date 01/31/96 will result in
683	* 02/29/96. Rolling by a positive value always means rolling forward in time (unless
684	* the limit of the field is reached, in which case it may pin or wrap), so for
685	* Gregorian calendar, starting with 100 BC and rolling the year by + 1 results in 99 BC.
686	* When eras have a definite beginning and end (as in the Chinese calendar, or as in
687	* most eras in the Japanese calendar) then rolling the year past either limit of the
688	* era will cause the year to wrap around. When eras only have a limit at one end,
689	* then attempting to roll the year past that limit will result in pinning the year
690	* at that limit. Note that for most calendars in which era 0 years move forward in
691	* time (such as Buddhist, Hebrew, or Islamic), it is possible for add or roll to
692	* result in negative years for era 0 (that is the only way to represent years before
693	* the calendar epoch).
694	* When rolling on the hour-in-day or Calendar::HOUR_OF_DAY field, it will roll the
695	* hour value in the range between 0 and 23, which is zero-based.
696	* <P>
697	* The only difference between roll() and add() is that roll() does not change
698	* the value of more significant fields when it reaches the minimum or maximum
699	* of its range, whereas add() does.
700	*
701	* @param field The time field.
702	* @param amount Indicates amount to roll.
703	* @param status Output param set to success/failure code on exit. If any value
704	* previously set in the time field is invalid, this will be set to
705	* an error status.
706	* @stable ICU 2.6.
707	*/
708	virtual void roll(UCalendarDateFields field, int32_t amount, UErrorCode& status);
709
710	#ifndef U_FORCE_HIDE_DEPRECATED_API
711	/**
712	* Return the difference between the given time and the time this
713	* calendar object is set to. If this calendar is set
714	* <em>before</em> the given time, the returned value will be
715	* positive. If this calendar is set <em>after</em> the given
716	* time, the returned value will be negative. The
717	* <code>field</code> parameter specifies the units of the return
718	* value. For example, if <code>fieldDifference(when,
719	* Calendar::MONTH)</code> returns 3, then this calendar is set to
720	* 3 months before <code>when</code>, and possibly some addition
721	* time less than one month.
722	*
723	* <p>As a side effect of this call, this calendar is advanced
724	* toward <code>when</code> by the given amount. That is, calling
725	* this method has the side effect of calling <code>add(field,
726	* n)</code>, where <code>n</code> is the return value.
727	*
728	* <p>Usage: To use this method, call it first with the largest
729	* field of interest, then with progressively smaller fields. For
730	* example:
731	*
732	* <pre>
733	* int y = cal->fieldDifference(when, Calendar::YEAR, err);
734	* int m = cal->fieldDifference(when, Calendar::MONTH, err);
735	* int d = cal->fieldDifference(when, Calendar::DATE, err);</pre>
736	*
737	* computes the difference between <code>cal</code> and
738	* <code>when</code> in years, months, and days.
739	*
740	* <p>Note: <code>fieldDifference()</code> is
741	* <em>asymmetrical</em>. That is, in the following code:
742	*
743	* <pre>
744	* cal->setTime(date1, err);
745	* int m1 = cal->fieldDifference(date2, Calendar::MONTH, err);
746	* int d1 = cal->fieldDifference(date2, Calendar::DATE, err);
747	* cal->setTime(date2, err);
748	* int m2 = cal->fieldDifference(date1, Calendar::MONTH, err);
749	* int d2 = cal->fieldDifference(date1, Calendar::DATE, err);</pre>
750	*
751	* one might expect that <code>m1 == -m2 && d1 == -d2</code>.
752	* However, this is not generally the case, because of
753	* irregularities in the underlying calendar system (e.g., the
754	* Gregorian calendar has a varying number of days per month).
755	*
756	* @param when the date to compare this calendar's time to
757	* @param field the field in which to compute the result
758	* @param status Output param set to success/failure code on exit. If any value
759	* previously set in the time field is invalid, this will be set to
760	* an error status.
761	* @return the difference, either positive or negative, between
762	* this calendar's time and <code>when</code>, in terms of
763	* <code>field</code>.
764	* @deprecated ICU 2.6. Use fieldDifference(UDate when, UCalendarDateFields field, UErrorCode& status).
765	*/
766	virtual int32_t fieldDifference(UDate when, EDateFields field, UErrorCode& status);
767	#endif // U_FORCE_HIDE_DEPRECATED_API
768
769	/**
770	* Return the difference between the given time and the time this
771	* calendar object is set to. If this calendar is set
772	* <em>before</em> the given time, the returned value will be
773	* positive. If this calendar is set <em>after</em> the given
774	* time, the returned value will be negative. The
775	* <code>field</code> parameter specifies the units of the return
776	* value. For example, if <code>fieldDifference(when,
777	* Calendar::MONTH)</code> returns 3, then this calendar is set to
778	* 3 months before <code>when</code>, and possibly some addition
779	* time less than one month.
780	*
781	* <p>As a side effect of this call, this calendar is advanced
782	* toward <code>when</code> by the given amount. That is, calling
783	* this method has the side effect of calling <code>add(field,
784	* n)</code>, where <code>n</code> is the return value.
785	*
786	* <p>Usage: To use this method, call it first with the largest
787	* field of interest, then with progressively smaller fields. For
788	* example:
789	*
790	* <pre>
791	* int y = cal->fieldDifference(when, Calendar::YEAR, err);
792	* int m = cal->fieldDifference(when, Calendar::MONTH, err);
793	* int d = cal->fieldDifference(when, Calendar::DATE, err);</pre>
794	*
795	* computes the difference between <code>cal</code> and
796	* <code>when</code> in years, months, and days.
797	*
798	* <p>Note: <code>fieldDifference()</code> is
799	* <em>asymmetrical</em>. That is, in the following code:
800	*
801	* <pre>
802	* cal->setTime(date1, err);
803	* int m1 = cal->fieldDifference(date2, Calendar::MONTH, err);
804	* int d1 = cal->fieldDifference(date2, Calendar::DATE, err);
805	* cal->setTime(date2, err);
806	* int m2 = cal->fieldDifference(date1, Calendar::MONTH, err);
807	* int d2 = cal->fieldDifference(date1, Calendar::DATE, err);</pre>
808	*
809	* one might expect that <code>m1 == -m2 && d1 == -d2</code>.
810	* However, this is not generally the case, because of
811	* irregularities in the underlying calendar system (e.g., the
812	* Gregorian calendar has a varying number of days per month).
813	*
814	* @param when the date to compare this calendar's time to
815	* @param field the field in which to compute the result
816	* @param status Output param set to success/failure code on exit. If any value
817	* previously set in the time field is invalid, this will be set to
818	* an error status.
819	* @return the difference, either positive or negative, between
820	* this calendar's time and <code>when</code>, in terms of
821	* <code>field</code>.
822	* @stable ICU 2.6.
823	*/
824	virtual int32_t fieldDifference(UDate when, UCalendarDateFields field, UErrorCode& status);
825
826	/**
827	* Sets the calendar's time zone to be the one passed in. The Calendar takes ownership
828	* of the TimeZone; the caller is no longer responsible for deleting it. If the
829	* given time zone is NULL, this function has no effect.
830	*
831	* @param value The given time zone.
832	* @stable ICU 2.0
833	*/
834	void adoptTimeZone(TimeZone* value);
835
836	/**
837	* Sets the calendar's time zone to be the same as the one passed in. The TimeZone
838	* passed in is _not_ adopted; the client is still responsible for deleting it.
839	*
840	* @param zone The given time zone.
841	* @stable ICU 2.0
842	*/
843	void setTimeZone(const TimeZone& zone);
844
845	/**
846	* Returns a reference to the time zone owned by this calendar. The returned reference
847	* is only valid until clients make another call to adoptTimeZone or setTimeZone,
848	* or this Calendar is destroyed.
849	*
850	* @return The time zone object associated with this calendar.
851	* @stable ICU 2.0
852	*/
853	const TimeZone& getTimeZone(void) const;
854
855	/**
856	* Returns the time zone owned by this calendar. The caller owns the returned object
857	* and must delete it when done. After this call, the new time zone associated
858	* with this Calendar is the default TimeZone as returned by TimeZone::createDefault().
859	*
860	* @return The time zone object which was associated with this calendar.
861	* @stable ICU 2.0
862	*/
863	TimeZone* orphanTimeZone(void);
864
865	/**
866	* Queries if the current date for this Calendar is in Daylight Savings Time.
867	*
868	* @param status Fill-in parameter which receives the status of this operation.
869	* @return True if the current date for this Calendar is in Daylight Savings Time,
870	* false, otherwise.
871	* @stable ICU 2.0
872	*/
873	virtual UBool inDaylightTime(UErrorCode& status) const = 0;
874
875	/**
876	* Specifies whether or not date/time interpretation is to be lenient. With lenient
877	* interpretation, a date such as "February 942, 1996" will be treated as being
878	* equivalent to the 941st day after February 1, 1996. With strict interpretation,
879	* such dates will cause an error when computing time from the time field values
880	* representing the dates.
881	*
882	* @param lenient True specifies date/time interpretation to be lenient.
883	*
884	* @see DateFormat#setLenient
885	* @stable ICU 2.0
886	*/
887	void setLenient(UBool lenient);
888
889	/**
890	* Tells whether date/time interpretation is to be lenient.
891	*
892	* @return True tells that date/time interpretation is to be lenient.
893	* @stable ICU 2.0
894	*/
895	UBool isLenient(void) const;
896
897	/**
898	* Sets the behavior for handling wall time repeating multiple times
899	* at negative time zone offset transitions. For example, 1:30 AM on
900	* November 6, 2011 in US Eastern time (America/New_York) occurs twice;
901	* 1:30 AM EDT, then 1:30 AM EST one hour later. When <code>UCAL_WALLTIME_FIRST</code>
902	* is used, the wall time 1:30AM in this example will be interpreted as 1:30 AM EDT
903	* (first occurrence). When <code>UCAL_WALLTIME_LAST</code> is used, it will be
904	* interpreted as 1:30 AM EST (last occurrence). The default value is
905	* <code>UCAL_WALLTIME_LAST</code>.
906	* <p>
907	* <b>Note:</b>When <code>UCAL_WALLTIME_NEXT_VALID</code> is not a valid
908	* option for this. When the argument is neither <code>UCAL_WALLTIME_FIRST</code>
909	* nor <code>UCAL_WALLTIME_LAST</code>, this method has no effect and will keep
910	* the current setting.
911	*
912	* @param option the behavior for handling repeating wall time, either
913	* <code>UCAL_WALLTIME_FIRST</code> or <code>UCAL_WALLTIME_LAST</code>.
914	* @see #getRepeatedWallTimeOption
915	* @stable ICU 49
916	*/
917	void setRepeatedWallTimeOption(UCalendarWallTimeOption option);
918
919	/**
920	* Gets the behavior for handling wall time repeating multiple times
921	* at negative time zone offset transitions.
922	*
923	* @return the behavior for handling repeating wall time, either
924	* <code>UCAL_WALLTIME_FIRST</code> or <code>UCAL_WALLTIME_LAST</code>.
925	* @see #setRepeatedWallTimeOption
926	* @stable ICU 49
927	*/
928	UCalendarWallTimeOption getRepeatedWallTimeOption(void) const;
929
930	/**
931	* Sets the behavior for handling skipped wall time at positive time zone offset
932	* transitions. For example, 2:30 AM on March 13, 2011 in US Eastern time (America/New_York)
933	* does not exist because the wall time jump from 1:59 AM EST to 3:00 AM EDT. When
934	* <code>UCAL_WALLTIME_FIRST</code> is used, 2:30 AM is interpreted as 30 minutes before 3:00 AM
935	* EDT, therefore, it will be resolved as 1:30 AM EST. When <code>UCAL_WALLTIME_LAST</code>
936	* is used, 2:30 AM is interpreted as 31 minutes after 1:59 AM EST, therefore, it will be
937	* resolved as 3:30 AM EDT. When <code>UCAL_WALLTIME_NEXT_VALID</code> is used, 2:30 AM will
938	* be resolved as next valid wall time, that is 3:00 AM EDT. The default value is
939	* <code>UCAL_WALLTIME_LAST</code>.
940	* <p>
941	* <b>Note:</b>This option is effective only when this calendar is lenient.
942	* When the calendar is strict, such non-existing wall time will cause an error.
943	*
944	* @param option the behavior for handling skipped wall time at positive time zone
945	* offset transitions, one of <code>UCAL_WALLTIME_FIRST</code>, <code>UCAL_WALLTIME_LAST</code> and
946	* <code>UCAL_WALLTIME_NEXT_VALID</code>.
947	* @see #getSkippedWallTimeOption
948	*
949	* @stable ICU 49
950	*/
951	void setSkippedWallTimeOption(UCalendarWallTimeOption option);
952
953	/**
954	* Gets the behavior for handling skipped wall time at positive time zone offset
955	* transitions.
956	*
957	* @return the behavior for handling skipped wall time, one of
958	* <code>UCAL_WALLTIME_FIRST</code>, <code>UCAL_WALLTIME_LAST</code>
959	* and <code>UCAL_WALLTIME_NEXT_VALID</code>.
960	* @see #setSkippedWallTimeOption
961	* @stable ICU 49
962	*/
963	UCalendarWallTimeOption getSkippedWallTimeOption(void) const;
964
965	#ifndef U_HIDE_DEPRECATED_API
966	/**
967	* Sets what the first day of the week is; e.g., Sunday in US, Monday in France.
968	*
969	* @param value The given first day of the week.
970	* @deprecated ICU 2.6. Use setFirstDayOfWeek(UCalendarDaysOfWeek value) instead.
971	*/
972	void setFirstDayOfWeek(EDaysOfWeek value);
973	#endif /* U_HIDE_DEPRECATED_API */
974
975	/**
976	* Sets what the first day of the week is; e.g., Sunday in US, Monday in France.
977	*
978	* @param value The given first day of the week.
979	* @stable ICU 2.6.
980	*/
981	void setFirstDayOfWeek(UCalendarDaysOfWeek value);
982
983	#ifndef U_HIDE_DEPRECATED_API
984	/**
985	* Gets what the first day of the week is; e.g., Sunday in US, Monday in France.
986	*
987	* @return The first day of the week.
988	* @deprecated ICU 2.6 use the overload with error code
989	*/
990	EDaysOfWeek getFirstDayOfWeek(void) const;
991	#endif /* U_HIDE_DEPRECATED_API */
992
993	/**
994	* Gets what the first day of the week is; e.g., Sunday in US, Monday in France.
995	*
996	* @param status error code
997	* @return The first day of the week.
998	* @stable ICU 2.6
999	*/
1000	UCalendarDaysOfWeek getFirstDayOfWeek(UErrorCode &status) const;
1001
1002	/**
1003	* Sets what the minimal days required in the first week of the year are; For
1004	* example, if the first week is defined as one that contains the first day of the
1005	* first month of a year, call the method with value 1. If it must be a full week,
1006	* use value 7.
1007	*
1008	* @param value The given minimal days required in the first week of the year.
1009	* @stable ICU 2.0
1010	*/
1011	void setMinimalDaysInFirstWeek(uint8_t value);
1012
1013	/**
1014	* Gets what the minimal days required in the first week of the year are; e.g., if
1015	* the first week is defined as one that contains the first day of the first month
1016	* of a year, getMinimalDaysInFirstWeek returns 1. If the minimal days required must
1017	* be a full week, getMinimalDaysInFirstWeek returns 7.
1018	*
1019	* @return The minimal days required in the first week of the year.
1020	* @stable ICU 2.0
1021	*/
1022	uint8_t getMinimalDaysInFirstWeek(void) const;
1023
1024	#ifndef U_FORCE_HIDE_DEPRECATED_API
1025	/**
1026	* Gets the minimum value for the given time field. e.g., for Gregorian
1027	* DAY_OF_MONTH, 1.
1028	*
1029	* @param field The given time field.
1030	* @return The minimum value for the given time field.
1031	* @deprecated ICU 2.6. Use getMinimum(UCalendarDateFields field) instead.
1032	*/
1033	virtual int32_t getMinimum(EDateFields field) const;
1034	#endif // U_FORCE_HIDE_DEPRECATED_API
1035
1036	/**
1037	* Gets the minimum value for the given time field. e.g., for Gregorian
1038	* DAY_OF_MONTH, 1.
1039	*
1040	* @param field The given time field.
1041	* @return The minimum value for the given time field.
1042	* @stable ICU 2.6.
1043	*/
1044	virtual int32_t getMinimum(UCalendarDateFields field) const;
1045
1046	#ifndef U_FORCE_HIDE_DEPRECATED_API
1047	/**
1048	* Gets the maximum value for the given time field. e.g. for Gregorian DAY_OF_MONTH,
1049	* 31.
1050	*
1051	* @param field The given time field.
1052	* @return The maximum value for the given time field.
1053	* @deprecated ICU 2.6. Use getMaximum(UCalendarDateFields field) instead.
1054	*/
1055	virtual int32_t getMaximum(EDateFields field) const;
1056	#endif // U_FORCE_HIDE_DEPRECATED_API
1057
1058	/**
1059	* Gets the maximum value for the given time field. e.g. for Gregorian DAY_OF_MONTH,
1060	* 31.
1061	*
1062	* @param field The given time field.
1063	* @return The maximum value for the given time field.
1064	* @stable ICU 2.6.
1065	*/
1066	virtual int32_t getMaximum(UCalendarDateFields field) const;
1067
1068	#ifndef U_FORCE_HIDE_DEPRECATED_API
1069	/**
1070	* Gets the highest minimum value for the given field if varies. Otherwise same as
1071	* getMinimum(). For Gregorian, no difference.
1072	*
1073	* @param field The given time field.
1074	* @return The highest minimum value for the given time field.
1075	* @deprecated ICU 2.6. Use getGreatestMinimum(UCalendarDateFields field) instead.
1076	*/
1077	virtual int32_t getGreatestMinimum(EDateFields field) const;
1078	#endif // U_FORCE_HIDE_DEPRECATED_API
1079
1080	/**
1081	* Gets the highest minimum value for the given field if varies. Otherwise same as
1082	* getMinimum(). For Gregorian, no difference.
1083	*
1084	* @param field The given time field.
1085	* @return The highest minimum value for the given time field.
1086	* @stable ICU 2.6.
1087	*/
1088	virtual int32_t getGreatestMinimum(UCalendarDateFields field) const;
1089
1090	#ifndef U_FORCE_HIDE_DEPRECATED_API
1091	/**
1092	* Gets the lowest maximum value for the given field if varies. Otherwise same as
1093	* getMaximum(). e.g., for Gregorian DAY_OF_MONTH, 28.
1094	*
1095	* @param field The given time field.
1096	* @return The lowest maximum value for the given time field.
1097	* @deprecated ICU 2.6. Use getLeastMaximum(UCalendarDateFields field) instead.
1098	*/
1099	virtual int32_t getLeastMaximum(EDateFields field) const;
1100	#endif // U_FORCE_HIDE_DEPRECATED_API
1101
1102	/**
1103	* Gets the lowest maximum value for the given field if varies. Otherwise same as
1104	* getMaximum(). e.g., for Gregorian DAY_OF_MONTH, 28.
1105	*
1106	* @param field The given time field.
1107	* @return The lowest maximum value for the given time field.
1108	* @stable ICU 2.6.
1109	*/
1110	virtual int32_t getLeastMaximum(UCalendarDateFields field) const;
1111
1112	#ifndef U_HIDE_DEPRECATED_API
1113	/**
1114	* Return the minimum value that this field could have, given the current date.
1115	* For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
1116	*
1117	* The version of this function on Calendar uses an iterative algorithm to determine the
1118	* actual minimum value for the field. There is almost always a more efficient way to
1119	* accomplish this (in most cases, you can simply return getMinimum()). GregorianCalendar
1120	* overrides this function with a more efficient implementation.
1121	*
1122	* @param field the field to determine the minimum of
1123	* @param status Fill-in parameter which receives the status of this operation.
1124	* @return the minimum of the given field for the current date of this Calendar
1125	* @deprecated ICU 2.6. Use getActualMinimum(UCalendarDateFields field, UErrorCode& status) instead.
1126	*/
1127	int32_t getActualMinimum(EDateFields field, UErrorCode& status) const;
1128	#endif /* U_HIDE_DEPRECATED_API */
1129
1130	/**
1131	* Return the minimum value that this field could have, given the current date.
1132	* For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
1133	*
1134	* The version of this function on Calendar uses an iterative algorithm to determine the
1135	* actual minimum value for the field. There is almost always a more efficient way to
1136	* accomplish this (in most cases, you can simply return getMinimum()). GregorianCalendar
1137	* overrides this function with a more efficient implementation.
1138	*
1139	* @param field the field to determine the minimum of
1140	* @param status Fill-in parameter which receives the status of this operation.
1141	* @return the minimum of the given field for the current date of this Calendar
1142	* @stable ICU 2.6.
1143	*/
1144	virtual int32_t getActualMinimum(UCalendarDateFields field, UErrorCode& status) const;
1145
1146	#ifndef U_HIDE_DEPRECATED_API
1147	/**
1148	* Return the maximum value that this field could have, given the current date.
1149	* For example, with the date "Feb 3, 1997" and the DAY_OF_MONTH field, the actual
1150	* maximum would be 28; for "Feb 3, 1996" it s 29. Similarly for a Hebrew calendar,
1151	* for some years the actual maximum for MONTH is 12, and for others 13.
1152	*
1153	* The version of this function on Calendar uses an iterative algorithm to determine the
1154	* actual maximum value for the field. There is almost always a more efficient way to
1155	* accomplish this (in most cases, you can simply return getMaximum()). GregorianCalendar
1156	* overrides this function with a more efficient implementation.
1157	*
1158	* @param field the field to determine the maximum of
1159	* @param status Fill-in parameter which receives the status of this operation.
1160	* @return the maximum of the given field for the current date of this Calendar
1161	* @deprecated ICU 2.6. Use getActualMaximum(UCalendarDateFields field, UErrorCode& status) instead.
1162	*/
1163	int32_t getActualMaximum(EDateFields field, UErrorCode& status) const;
1164	#endif /* U_HIDE_DEPRECATED_API */
1165
1166	/**
1167	* Return the maximum value that this field could have, given the current date.
1168	* For example, with the date "Feb 3, 1997" and the DAY_OF_MONTH field, the actual
1169	* maximum would be 28; for "Feb 3, 1996" it s 29. Similarly for a Hebrew calendar,
1170	* for some years the actual maximum for MONTH is 12, and for others 13.
1171	*
1172	* The version of this function on Calendar uses an iterative algorithm to determine the
1173	* actual maximum value for the field. There is almost always a more efficient way to
1174	* accomplish this (in most cases, you can simply return getMaximum()). GregorianCalendar
1175	* overrides this function with a more efficient implementation.
1176	*
1177	* @param field the field to determine the maximum of
1178	* @param status Fill-in parameter which receives the status of this operation.
1179	* @return the maximum of the given field for the current date of this Calendar
1180	* @stable ICU 2.6.
1181	*/
1182	virtual int32_t getActualMaximum(UCalendarDateFields field, UErrorCode& status) const;
1183
1184	#ifndef U_HIDE_DEPRECATED_API
1185	/**
1186	* Gets the value for a given time field. Recalculate the current time field values
1187	* if the time value has been changed by a call to setTime(). Return zero for unset
1188	* fields if any fields have been explicitly set by a call to set(). To force a
1189	* recomputation of all fields regardless of the previous state, call complete().
1190	* This method is semantically const, but may alter the object in memory.
1191	*
1192	* @param field The given time field.
1193	* @param status Fill-in parameter which receives the status of the operation.
1194	* @return The value for the given time field, or zero if the field is unset,
1195	* and set() has been called for any other field.
1196	* @deprecated ICU 2.6. Use get(UCalendarDateFields field, UErrorCode& status) instead.
1197	*/
1198	int32_t get(EDateFields field, UErrorCode& status) const;
1199	#endif /* U_HIDE_DEPRECATED_API */
1200
1201	/**
1202	* Gets the value for a given time field. Recalculate the current time field values
1203	* if the time value has been changed by a call to setTime(). Return zero for unset
1204	* fields if any fields have been explicitly set by a call to set(). To force a
1205	* recomputation of all fields regardless of the previous state, call complete().
1206	* This method is semantically const, but may alter the object in memory.
1207	*
1208	* @param field The given time field.
1209	* @param status Fill-in parameter which receives the status of the operation.
1210	* @return The value for the given time field, or zero if the field is unset,
1211	* and set() has been called for any other field.
1212	* @stable ICU 2.6.
1213	*/
1214	int32_t get(UCalendarDateFields field, UErrorCode& status) const;
1215
1216	#ifndef U_HIDE_DEPRECATED_API
1217	/**
1218	* Determines if the given time field has a value set. This can affect in the
1219	* resolving of time in Calendar. Unset fields have a value of zero, by definition.
1220	*
1221	* @param field The given time field.
1222	* @return True if the given time field has a value set; false otherwise.
1223	* @deprecated ICU 2.6. Use isSet(UCalendarDateFields field) instead.
1224	*/
1225	UBool isSet(EDateFields field) const;
1226	#endif /* U_HIDE_DEPRECATED_API */
1227
1228	/**
1229	* Determines if the given time field has a value set. This can affect in the
1230	* resolving of time in Calendar. Unset fields have a value of zero, by definition.
1231	*
1232	* @param field The given time field.
1233	* @return True if the given time field has a value set; false otherwise.
1234	* @stable ICU 2.6.
1235	*/
1236	UBool isSet(UCalendarDateFields field) const;
1237
1238	#ifndef U_HIDE_DEPRECATED_API
1239	/**
1240	* Sets the given time field with the given value.
1241	*
1242	* @param field The given time field.
1243	* @param value The value to be set for the given time field.
1244	* @deprecated ICU 2.6. Use set(UCalendarDateFields field, int32_t value) instead.
1245	*/
1246	void set(EDateFields field, int32_t value);
1247	#endif /* U_HIDE_DEPRECATED_API */
1248
1249	/**
1250	* Sets the given time field with the given value.
1251	*
1252	* @param field The given time field.
1253	* @param value The value to be set for the given time field.
1254	* @stable ICU 2.6.
1255	*/
1256	void set(UCalendarDateFields field, int32_t value);
1257
1258	/**
1259	* Sets the values for the fields YEAR, MONTH, and DATE. Other field values are
1260	* retained; call clear() first if this is not desired.
1261	*
1262	* @param year The value used to set the YEAR time field.
1263	* @param month The value used to set the MONTH time field. Month value is 0-based.
1264	* e.g., 0 for January.
1265	* @param date The value used to set the DATE time field.
1266	* @stable ICU 2.0
1267	*/
1268	void set(int32_t year, int32_t month, int32_t date);
1269
1270	/**
1271	* Sets the values for the fields YEAR, MONTH, DATE, HOUR_OF_DAY, and MINUTE. Other
1272	* field values are retained; call clear() first if this is not desired.
1273	*
1274	* @param year The value used to set the YEAR time field.
1275	* @param month The value used to set the MONTH time field. Month value is
1276	* 0-based. E.g., 0 for January.
1277	* @param date The value used to set the DATE time field.
1278	* @param hour The value used to set the HOUR_OF_DAY time field.
1279	* @param minute The value used to set the MINUTE time field.
1280	* @stable ICU 2.0
1281	*/
1282	void set(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute);
1283
1284	/**
1285	* Sets the values for the fields YEAR, MONTH, DATE, HOUR_OF_DAY, MINUTE, and SECOND.
1286	* Other field values are retained; call clear() first if this is not desired.
1287	*
1288	* @param year The value used to set the YEAR time field.
1289	* @param month The value used to set the MONTH time field. Month value is
1290	* 0-based. E.g., 0 for January.
1291	* @param date The value used to set the DATE time field.
1292	* @param hour The value used to set the HOUR_OF_DAY time field.
1293	* @param minute The value used to set the MINUTE time field.
1294	* @param second The value used to set the SECOND time field.
1295	* @stable ICU 2.0
1296	*/
1297	void set(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, int32_t second);
1298
1299	/**
1300	* Clears the values of all the time fields, making them both unset and assigning
1301	* them a value of zero. The field values will be determined during the next
1302	* resolving of time into time fields.
1303	* @stable ICU 2.0
1304	*/
1305	void clear(void);
1306
1307	#ifndef U_HIDE_DEPRECATED_API
1308	/**
1309	* Clears the value in the given time field, both making it unset and assigning it a
1310	* value of zero. This field value will be determined during the next resolving of
1311	* time into time fields.
1312	*
1313	* @param field The time field to be cleared.
1314	* @deprecated ICU 2.6. Use clear(UCalendarDateFields field) instead.
1315	*/
1316	void clear(EDateFields field);
1317	#endif /* U_HIDE_DEPRECATED_API */
1318
1319	/**
1320	* Clears the value in the given time field, both making it unset and assigning it a
1321	* value of zero. This field value will be determined during the next resolving of
1322	* time into time fields.
1323	*
1324	* @param field The time field to be cleared.
1325	* @stable ICU 2.6.
1326	*/
1327	void clear(UCalendarDateFields field);
1328
1329	/**
1330	* Returns a unique class ID POLYMORPHICALLY. Pure virtual method. This method is to
1331	* implement a simple version of RTTI, since not all C++ compilers support genuine
1332	* RTTI. Polymorphic operator==() and clone() methods call this method.
1333	* <P>
1334	* Concrete subclasses of Calendar must implement getDynamicClassID() and also a
1335	* static method and data member:
1336	*
1337	* static UClassID getStaticClassID() { return (UClassID)&amp;fgClassID; }
1338	* static char fgClassID;
1339	*
1340	* @return The class ID for this object. All objects of a given class have the
1341	* same class ID. Objects of other classes have different class IDs.
1342	* @stable ICU 2.0
1343	*/
1344	virtual UClassID getDynamicClassID(void) const override = 0;
1345
1346	/**
1347	* Returns the calendar type name string for this Calendar object.
1348	* The returned string is the legacy ICU calendar attribute value,
1349	* for example, "gregorian" or "japanese".
1350	*
1351	* See type="old type name" for the calendar attribute of locale IDs
1352	* at http://www.unicode.org/reports/tr35/#Key_Type_Definitions
1353	*
1354	* Sample code for getting the LDML/BCP 47 calendar key value:
1355	* \code
1356	* const char *calType = cal->getType();
1357	* if (0 == strcmp(calType, "unknown")) {
1358	* // deal with unknown calendar type
1359	* } else {
1360	* string localeID("root@calendar=");
1361	* localeID.append(calType);
1362	* char langTag[100];
1363	* UErrorCode errorCode = U_ZERO_ERROR;
1364	* int32_t length = uloc_toLanguageTag(localeID.c_str(), langTag, (int32_t)sizeof(langTag), true, &errorCode);
1365	* if (U_FAILURE(errorCode)) {
1366	* // deal with errors & overflow
1367	* }
1368	* string lang(langTag, length);
1369	* size_t caPos = lang.find("-ca-");
1370	* lang.erase(0, caPos + 4);
1371	* // lang now contains the LDML calendar type
1372	* }
1373	* \endcode
1374	*
1375	* @return legacy calendar type name string
1376	* @stable ICU 49
1377	*/
1378	virtual const char * getType() const = 0;
1379
1380	/**
1381	* Returns whether the given day of the week is a weekday, a weekend day,
1382	* or a day that transitions from one to the other, for the locale and
1383	* calendar system associated with this Calendar (the locale's region is
1384	* often the most determinant factor). If a transition occurs at midnight,
1385	* then the days before and after the transition will have the
1386	* type UCAL_WEEKDAY or UCAL_WEEKEND. If a transition occurs at a time
1387	* other than midnight, then the day of the transition will have
1388	* the type UCAL_WEEKEND_ONSET or UCAL_WEEKEND_CEASE. In this case, the
1389	* method getWeekendTransition() will return the point of
1390	* transition.
1391	* @param dayOfWeek The day of the week whose type is desired (UCAL_SUNDAY..UCAL_SATURDAY).
1392	* @param status The error code for the operation.
1393	* @return The UCalendarWeekdayType for the day of the week.
1394	* @stable ICU 4.4
1395	*/
1396	virtual UCalendarWeekdayType getDayOfWeekType(UCalendarDaysOfWeek dayOfWeek, UErrorCode &status) const;
1397
1398	/**
1399	* Returns the time during the day at which the weekend begins or ends in
1400	* this calendar system. If getDayOfWeekType() returns UCAL_WEEKEND_ONSET
1401	* for the specified dayOfWeek, return the time at which the weekend begins.
1402	* If getDayOfWeekType() returns UCAL_WEEKEND_CEASE for the specified dayOfWeek,
1403	* return the time at which the weekend ends. If getDayOfWeekType() returns
1404	* some other UCalendarWeekdayType for the specified dayOfWeek, is it an error condition
1405	* (U_ILLEGAL_ARGUMENT_ERROR).
1406	* @param dayOfWeek The day of the week for which the weekend transition time is
1407	* desired (UCAL_SUNDAY..UCAL_SATURDAY).
1408	* @param status The error code for the operation.
1409	* @return The milliseconds after midnight at which the weekend begins or ends.
1410	* @stable ICU 4.4
1411	*/
1412	virtual int32_t getWeekendTransition(UCalendarDaysOfWeek dayOfWeek, UErrorCode &status) const;
1413
1414	/**
1415	* Returns true if the given UDate is in the weekend in
1416	* this calendar system.
1417	* @param date The UDate in question.
1418	* @param status The error code for the operation.
1419	* @return true if the given UDate is in the weekend in
1420	* this calendar system, false otherwise.
1421	* @stable ICU 4.4
1422	*/
1423	virtual UBool isWeekend(UDate date, UErrorCode &status) const;
1424
1425	/**
1426	* Returns true if this Calendar's current date-time is in the weekend in
1427	* this calendar system.
1428	* @return true if this Calendar's current date-time is in the weekend in
1429	* this calendar system, false otherwise.
1430	* @stable ICU 4.4
1431	*/
1432	virtual UBool isWeekend(void) const;
1433
1434	protected:
1435
1436	/**
1437	* Constructs a Calendar with the default time zone as returned by
1438	* TimeZone::createInstance(), and the default locale.
1439	*
1440	* @param success Indicates the status of Calendar object construction. Returns
1441	* U_ZERO_ERROR if constructed successfully.
1442	* @stable ICU 2.0
1443	*/
1444	Calendar(UErrorCode& success);
1445
1446	/**
1447	* Copy constructor
1448	*
1449	* @param source Calendar object to be copied from
1450	* @stable ICU 2.0
1451	*/
1452	Calendar(const Calendar& source);
1453
1454	/**
1455	* Default assignment operator
1456	*
1457	* @param right Calendar object to be copied
1458	* @stable ICU 2.0
1459	*/
1460	Calendar& operator=(const Calendar& right);
1461
1462	/**
1463	* Constructs a Calendar with the given time zone and locale. Clients are no longer
1464	* responsible for deleting the given time zone object after it's adopted.
1465	*
1466	* @param zone The given time zone.
1467	* @param aLocale The given locale.
1468	* @param success Indicates the status of Calendar object construction. Returns
1469	* U_ZERO_ERROR if constructed successfully.
1470	* @stable ICU 2.0
1471	*/
1472	Calendar(TimeZone* zone, const Locale& aLocale, UErrorCode& success);
1473
1474	/**
1475	* Constructs a Calendar with the given time zone and locale.
1476	*
1477	* @param zone The given time zone.
1478	* @param aLocale The given locale.
1479	* @param success Indicates the status of Calendar object construction. Returns
1480	* U_ZERO_ERROR if constructed successfully.
1481	* @stable ICU 2.0
1482	*/
1483	Calendar(const TimeZone& zone, const Locale& aLocale, UErrorCode& success);
1484
1485	/**
1486	* Converts Calendar's time field values to GMT as milliseconds.
1487	*
1488	* @param status Output param set to success/failure code on exit. If any value
1489	* previously set in the time field is invalid or restricted by
1490	* leniency, this will be set to an error status.
1491	* @stable ICU 2.0
1492	*/
1493	virtual void computeTime(UErrorCode& status);
1494
1495	/**
1496	* Converts GMT as milliseconds to time field values. This allows you to sync up the
1497	* time field values with a new time that is set for the calendar. This method
1498	* does NOT recompute the time first; to recompute the time, then the fields, use
1499	* the method complete().
1500	*
1501	* @param status Output param set to success/failure code on exit. If any value
1502	* previously set in the time field is invalid or restricted by
1503	* leniency, this will be set to an error status.
1504	* @stable ICU 2.0
1505	*/
1506	virtual void computeFields(UErrorCode& status);
1507
1508	/**
1509	* Gets this Calendar's current time as a long.
1510	*
1511	* @param status Output param set to success/failure code on exit. If any value
1512	* previously set in the time field is invalid or restricted by
1513	* leniency, this will be set to an error status.
1514	* @return the current time as UTC milliseconds from the epoch.
1515	* @stable ICU 2.0
1516	*/
1517	double getTimeInMillis(UErrorCode& status) const;
1518
1519	/**
1520	* Sets this Calendar's current time from the given long value.
1521	* @param millis the new time in UTC milliseconds from the epoch.
1522	* @param status Output param set to success/failure code on exit. If any value
1523	* previously set in the time field is invalid or restricted by
1524	* leniency, this will be set to an error status.
1525	* @stable ICU 2.0
1526	*/
1527	void setTimeInMillis( double millis, UErrorCode& status );
1528
1529	/**
1530	* Recomputes the current time from currently set fields, and then fills in any
1531	* unset fields in the time field list.
1532	*
1533	* @param status Output param set to success/failure code on exit. If any value
1534	* previously set in the time field is invalid or restricted by
1535	* leniency, this will be set to an error status.
1536	* @stable ICU 2.0
1537	*/
1538	void complete(UErrorCode& status);
1539
1540	#ifndef U_HIDE_DEPRECATED_API
1541	/**
1542	* Gets the value for a given time field. Subclasses can use this function to get
1543	* field values without forcing recomputation of time.
1544	*
1545	* @param field The given time field.
1546	* @return The value for the given time field.
1547	* @deprecated ICU 2.6. Use internalGet(UCalendarDateFields field) instead.
1548	*/
1549	inline int32_t internalGet(EDateFields field) const {return fFields[field];}
1550	#endif /* U_HIDE_DEPRECATED_API */
1551
1552	#ifndef U_HIDE_INTERNAL_API
1553	/**
1554	* Gets the value for a given time field. Subclasses can use this function to get
1555	* field values without forcing recomputation of time. If the field's stamp is UNSET,
1556	* the defaultValue is used.
1557	*
1558	* @param field The given time field.
1559	* @param defaultValue a default value used if the field is unset.
1560	* @return The value for the given time field.
1561	* @internal
1562	*/
1563	inline int32_t internalGet(UCalendarDateFields field, int32_t defaultValue) const {return fStamp[field]>kUnset ? fFields[field] : defaultValue;}
1564
1565	/**
1566	* Gets the value for a given time field. Subclasses can use this function to get
1567	* field values without forcing recomputation of time.
1568	*
1569	* @param field The given time field.
1570	* @return The value for the given time field.
1571	* @internal
1572	*/
1573	inline int32_t internalGet(UCalendarDateFields field) const {return fFields[field];}
1574	#endif /* U_HIDE_INTERNAL_API */
1575
1576	#ifndef U_HIDE_DEPRECATED_API
1577	/**
1578	* Sets the value for a given time field. This is a fast internal method for
1579	* subclasses. It does not affect the areFieldsInSync, isTimeSet, or areAllFieldsSet
1580	* flags.
1581	*
1582	* @param field The given time field.
1583	* @param value The value for the given time field.
1584	* @deprecated ICU 2.6. Use internalSet(UCalendarDateFields field, int32_t value) instead.
1585	*/
1586	void internalSet(EDateFields field, int32_t value);
1587	#endif /* U_HIDE_DEPRECATED_API */
1588
1589	/**
1590	* Sets the value for a given time field. This is a fast internal method for
1591	* subclasses. It does not affect the areFieldsInSync, isTimeSet, or areAllFieldsSet
1592	* flags.
1593	*
1594	* @param field The given time field.
1595	* @param value The value for the given time field.
1596	* @stable ICU 2.6.
1597	*/
1598	inline void internalSet(UCalendarDateFields field, int32_t value);
1599
1600	/**
1601	* Prepare this calendar for computing the actual minimum or maximum.
1602	* This method modifies this calendar's fields; it is called on a
1603	* temporary calendar.
1604	* @internal
1605	*/
1606	virtual void prepareGetActual(UCalendarDateFields field, UBool isMinimum, UErrorCode &status);
1607
1608	/**
1609	* Limit enums. Not in sync with UCalendarLimitType (refers to internal fields).
1610	* @internal
1611	*/
1612	enum ELimitType {
1613	#ifndef U_HIDE_INTERNAL_API
1614	UCAL_LIMIT_MINIMUM = 0,
1615	UCAL_LIMIT_GREATEST_MINIMUM,
1616	UCAL_LIMIT_LEAST_MAXIMUM,
1617	UCAL_LIMIT_MAXIMUM,
1618	UCAL_LIMIT_COUNT
1619	#endif /* U_HIDE_INTERNAL_API */
1620	};
1621
1622	/**
1623	* Subclass API for defining limits of different types.
1624	* Subclasses must implement this method to return limits for the
1625	* following fields:
1626	*
1627	* <pre>UCAL_ERA
1628	* UCAL_YEAR
1629	* UCAL_MONTH
1630	* UCAL_WEEK_OF_YEAR
1631	* UCAL_WEEK_OF_MONTH
1632	* UCAL_DATE (DAY_OF_MONTH on Java)
1633	* UCAL_DAY_OF_YEAR
1634	* UCAL_DAY_OF_WEEK_IN_MONTH
1635	* UCAL_YEAR_WOY
1636	* UCAL_EXTENDED_YEAR</pre>
1637	*
1638	* @param field one of the above field numbers
1639	* @param limitType one of <code>MINIMUM</code>, <code>GREATEST_MINIMUM</code>,
1640	* <code>LEAST_MAXIMUM</code>, or <code>MAXIMUM</code>
1641	* @internal
1642	*/
1643	virtual int32_t handleGetLimit(UCalendarDateFields field, ELimitType limitType) const = 0;
1644
1645	/**
1646	* Return a limit for a field.
1647	* @param field the field, from <code>0..UCAL_MAX_FIELD</code>
1648	* @param limitType the type specifier for the limit
1649	* @see #ELimitType
1650	* @internal
1651	*/
1652	virtual int32_t getLimit(UCalendarDateFields field, ELimitType limitType) const;
1653
1654
1655	/**
1656	* Return the Julian day number of day before the first day of the
1657	* given month in the given extended year. Subclasses should override
1658	* this method to implement their calendar system.
1659	* @param eyear the extended year
1660	* @param month the zero-based month, or 0 if useMonth is false
1661	* @param useMonth if false, compute the day before the first day of
1662	* the given year, otherwise, compute the day before the first day of
1663	* the given month
1664	* @return the Julian day number of the day before the first
1665	* day of the given month and year
1666	* @internal
1667	*/
1668	virtual int32_t handleComputeMonthStart(int32_t eyear, int32_t month,
1669	UBool useMonth) const = 0;
1670
1671	/**
1672	* Return the number of days in the given month of the given extended
1673	* year of this calendar system. Subclasses should override this
1674	* method if they can provide a more correct or more efficient
1675	* implementation than the default implementation in Calendar.
1676	* @internal
1677	*/
1678	virtual int32_t handleGetMonthLength(int32_t extendedYear, int32_t month) const ;
1679
1680	/**
1681	* Return the number of days in the given extended year of this
1682	* calendar system. Subclasses should override this method if they can
1683	* provide a more correct or more efficient implementation than the
1684	* default implementation in Calendar.
1685	* @stable ICU 2.0
1686	*/
1687	virtual int32_t handleGetYearLength(int32_t eyear) const;
1688
1689
1690	/**
1691	* Return the extended year defined by the current fields. This will
1692	* use the UCAL_EXTENDED_YEAR field or the UCAL_YEAR and supra-year fields (such
1693	* as UCAL_ERA) specific to the calendar system, depending on which set of
1694	* fields is newer.
1695	* @return the extended year
1696	* @internal
1697	*/
1698	virtual int32_t handleGetExtendedYear() = 0;
1699
1700	/**
1701	* Subclasses may override this. This method calls
1702	* handleGetMonthLength() to obtain the calendar-specific month
1703	* length.
1704	* @param bestField which field to use to calculate the date
1705	* @return julian day specified by calendar fields.
1706	* @internal
1707	*/
1708	virtual int32_t handleComputeJulianDay(UCalendarDateFields bestField);
1709
1710	/**
1711	* Subclasses must override this to convert from week fields
1712	* (YEAR_WOY and WEEK_OF_YEAR) to an extended year in the case
1713	* where YEAR, EXTENDED_YEAR are not set.
1714	* The Calendar implementation assumes yearWoy is in extended gregorian form
1715	* @return the extended year, UCAL_EXTENDED_YEAR
1716	* @internal
1717	*/
1718	virtual int32_t handleGetExtendedYearFromWeekFields(int32_t yearWoy, int32_t woy);
1719
1720	/**
1721	* Validate a single field of this calendar. Subclasses should
1722	* override this method to validate any calendar-specific fields.
1723	* Generic fields can be handled by `Calendar::validateField()`.
1724	* @internal
1725	*/
1726	virtual void validateField(UCalendarDateFields field, UErrorCode &status);
1727
1728	#ifndef U_HIDE_INTERNAL_API
1729	/**
1730	* Compute the Julian day from fields. Will determine whether to use
1731	* the JULIAN_DAY field directly, or other fields.
1732	* @return the julian day
1733	* @internal
1734	*/
1735	int32_t computeJulianDay();
1736
1737	/**
1738	* Compute the milliseconds in the day from the fields. This is a
1739	* value from 0 to 23:59:59.999 inclusive, unless fields are out of
1740	* range, in which case it can be an arbitrary value. This value
1741	* reflects local zone wall time.
1742	* @internal
1743	*/
1744	double computeMillisInDay();
1745
1746	/**
1747	* This method can assume EXTENDED_YEAR has been set.
1748	* @param millis milliseconds of the date fields
1749	* @param millisInDay milliseconds of the time fields; may be out
1750	* or range.
1751	* @param ec Output param set to failure code on function return
1752	* when this function fails.
1753	* @internal
1754	*/
1755	int32_t computeZoneOffset(double millis, double millisInDay, UErrorCode &ec);
1756
1757
1758	/**
1759	* Determine the best stamp in a range.
1760	* @param start first enum to look at
1761	* @param end last enum to look at
1762	* @param bestSoFar stamp prior to function call
1763	* @return the stamp value of the best stamp
1764	* @internal
1765	*/
1766	int32_t newestStamp(UCalendarDateFields start, UCalendarDateFields end, int32_t bestSoFar) const;
1767
1768	/**
1769	* Values for field resolution tables
1770	* @see #resolveFields
1771	* @internal
1772	*/
1773	enum {
1774	/** Marker for end of resolve set (row or group). */
1775	kResolveSTOP = -1,
1776	/** Value to be bitwised "ORed" against resolve table field values for remapping. Example: (UCAL_DATE | kResolveRemap) in 1st column will cause 'UCAL_DATE' to be returned, but will not examine the value of UCAL_DATE. */
1777	kResolveRemap = 32
1778	};
1779
1780	/**
1781	* Precedence table for Dates
1782	* @see #resolveFields
1783	* @internal
1784	*/
1785	static const UFieldResolutionTable kDatePrecedence[];
1786
1787	/**
1788	* Precedence table for Year
1789	* @see #resolveFields
1790	* @internal
1791	*/
1792	static const UFieldResolutionTable kYearPrecedence[];
1793
1794	/**
1795	* Precedence table for Day of Week
1796	* @see #resolveFields
1797	* @internal
1798	*/
1799	static const UFieldResolutionTable kDOWPrecedence[];
1800
1801	/**
1802	* Given a precedence table, return the newest field combination in
1803	* the table, or UCAL_FIELD_COUNT if none is found.
1804	*
1805	* <p>The precedence table is a 3-dimensional array of integers. It
1806	* may be thought of as an array of groups. Each group is an array of
1807	* lines. Each line is an array of field numbers. Within a line, if
1808	* all fields are set, then the time stamp of the line is taken to be
1809	* the stamp of the most recently set field. If any field of a line is
1810	* unset, then the line fails to match. Within a group, the line with
1811	* the newest time stamp is selected. The first field of the line is
1812	* returned to indicate which line matched.
1813	*
1814	* <p>In some cases, it may be desirable to map a line to field that
1815	* whose stamp is NOT examined. For example, if the best field is
1816	* DAY_OF_WEEK then the DAY_OF_WEEK_IN_MONTH algorithm may be used. In
1817	* order to do this, insert the value <code>kResolveRemap | F</code> at
1818	* the start of the line, where <code>F</code> is the desired return
1819	* field value. This field will NOT be examined; it only determines
1820	* the return value if the other fields in the line are the newest.
1821	*
1822	* <p>If all lines of a group contain at least one unset field, then no
1823	* line will match, and the group as a whole will fail to match. In
1824	* that case, the next group will be processed. If all groups fail to
1825	* match, then UCAL_FIELD_COUNT is returned.
1826	* @internal
1827	*/
1828	UCalendarDateFields resolveFields(const UFieldResolutionTable *precedenceTable);
1829	#endif /* U_HIDE_INTERNAL_API */
1830
1831
1832	/**
1833	* @internal
1834	*/
1835	virtual const UFieldResolutionTable* getFieldResolutionTable() const;
1836
1837	#ifndef U_HIDE_INTERNAL_API
1838	/**
1839	* Return the field that is newer, either defaultField, or
1840	* alternateField. If neither is newer or neither is set, return defaultField.
1841	* @internal
1842	*/
1843	UCalendarDateFields newerField(UCalendarDateFields defaultField, UCalendarDateFields alternateField) const;
1844	#endif /* U_HIDE_INTERNAL_API */
1845
1846
1847	private:
1848	/**
1849	* Helper function for calculating limits by trial and error
1850	* @param field The field being investigated
1851	* @param startValue starting (least max) value of field
1852	* @param endValue ending (greatest max) value of field
1853	* @param status return type
1854	* @internal (private)
1855	*/
1856	int32_t getActualHelper(UCalendarDateFields field, int32_t startValue, int32_t endValue, UErrorCode &status) const;
1857
1858
1859	protected:
1860	/**
1861	* The flag which indicates if the current time is set in the calendar.
1862	* @stable ICU 2.0
1863	*/
1864	UBool fIsTimeSet;
1865
1866	/**
1867	* True if the fields are in sync with the currently set time of this Calendar.
1868	* If false, then the next attempt to get the value of a field will
1869	* force a recomputation of all fields from the current value of the time
1870	* field.
1871	* <P>
1872	* This should really be named areFieldsInSync, but the old name is retained
1873	* for backward compatibility.
1874	* @stable ICU 2.0
1875	*/
1876	UBool fAreFieldsSet;
1877
1878	/**
1879	* True if all of the fields have been set. This is initially false, and set to
1880	* true by computeFields().
1881	* @stable ICU 2.0
1882	*/
1883	UBool fAreAllFieldsSet;
1884
1885	/**
1886	* True if all fields have been virtually set, but have not yet been
1887	* computed. This occurs only in setTimeInMillis(). A calendar set
1888	* to this state will compute all fields from the time if it becomes
1889	* necessary, but otherwise will delay such computation.
1890	* @stable ICU 3.0
1891	*/
1892	UBool fAreFieldsVirtuallySet;
1893
1894	/**
1895	* Get the current time without recomputing.
1896	*
1897	* @return the current time without recomputing.
1898	* @stable ICU 2.0
1899	*/
1900	UDate internalGetTime(void) const { return fTime; }
1901
1902	/**
1903	* Set the current time without affecting flags or fields.
1904	*
1905	* @param time The time to be set
1906	* @return the current time without recomputing.
1907	* @stable ICU 2.0
1908	*/
1909	void internalSetTime(UDate time) { fTime = time; }
1910
1911	/**
1912	* The time fields containing values into which the millis is computed.
1913	* @stable ICU 2.0
1914	*/
1915	int32_t fFields[UCAL_FIELD_COUNT];
1916
1917	#ifndef U_FORCE_HIDE_DEPRECATED_API
1918	/**
1919	* The flags which tell if a specified time field for the calendar is set.
1920	* @deprecated ICU 2.8 use (fStamp[n]!=kUnset)
1921	*/
1922	UBool fIsSet[UCAL_FIELD_COUNT];
1923	#endif // U_FORCE_HIDE_DEPRECATED_API
1924
1925	/** Special values of stamp[]
1926	* @stable ICU 2.0
1927	*/
1928	enum {
1929	kUnset = 0,
1930	kInternallySet,
1931	kMinimumUserStamp
1932	};
1933
1934	/**
1935	* Pseudo-time-stamps which specify when each field was set. There
1936	* are two special values, UNSET and INTERNALLY_SET. Values from
1937	* MINIMUM_USER_SET to Integer.MAX_VALUE are legal user set values.
1938	* @stable ICU 2.0
1939	*/
1940	int32_t fStamp[UCAL_FIELD_COUNT];
1941
1942	/**
1943	* Subclasses may override this method to compute several fields
1944	* specific to each calendar system. These are:
1945	*
1946	* <ul><li>ERA
1947	* <li>YEAR
1948	* <li>MONTH
1949	* <li>DAY_OF_MONTH
1950	* <li>DAY_OF_YEAR
1951	* <li>EXTENDED_YEAR</ul>
1952	*
1953	* Subclasses can refer to the DAY_OF_WEEK and DOW_LOCAL fields, which
1954	* will be set when this method is called. Subclasses can also call
1955	* the getGregorianXxx() methods to obtain Gregorian calendar
1956	* equivalents for the given Julian day.
1957	*
1958	* <p>In addition, subclasses should compute any subclass-specific
1959	* fields, that is, fields from BASE_FIELD_COUNT to
1960	* getFieldCount() - 1.
1961	*
1962	* <p>The default implementation in <code>Calendar</code> implements
1963	* a pure proleptic Gregorian calendar.
1964	* @internal
1965	*/
1966	virtual void handleComputeFields(int32_t julianDay, UErrorCode &status);
1967
1968	#ifndef U_HIDE_INTERNAL_API
1969	/**
1970	* Return the extended year on the Gregorian calendar as computed by
1971	* <code>computeGregorianFields()</code>.
1972	* @internal
1973	*/
1974	int32_t getGregorianYear() const {
1975	return fGregorianYear;
1976	}
1977
1978	/**
1979	* Return the month (0-based) on the Gregorian calendar as computed by
1980	* <code>computeGregorianFields()</code>.
1981	* @internal
1982	*/
1983	int32_t getGregorianMonth() const {
1984	return fGregorianMonth;
1985	}
1986
1987	/**
1988	* Return the day of year (1-based) on the Gregorian calendar as
1989	* computed by <code>computeGregorianFields()</code>.
1990	* @internal
1991	*/
1992	int32_t getGregorianDayOfYear() const {
1993	return fGregorianDayOfYear;
1994	}
1995
1996	/**
1997	* Return the day of month (1-based) on the Gregorian calendar as
1998	* computed by <code>computeGregorianFields()</code>.
1999	* @internal
2000	*/
2001	int32_t getGregorianDayOfMonth() const {
2002	return fGregorianDayOfMonth;
2003	}
2004	#endif /* U_HIDE_INTERNAL_API */
2005
2006	/**
2007	* Called by computeJulianDay. Returns the default month (0-based) for the year,
2008	* taking year and era into account. Defaults to 0 for Gregorian, which doesn't care.
2009	* @param eyear The extended year
2010	* @internal
2011	*/
2012	virtual int32_t getDefaultMonthInYear(int32_t eyear) ;
2013
2014
2015	/**
2016	* Called by computeJulianDay. Returns the default day (1-based) for the month,
2017	* taking currently-set year and era into account. Defaults to 1 for Gregorian.
2018	* @param eyear the extended year
2019	* @param month the month in the year
2020	* @internal
2021	*/
2022	virtual int32_t getDefaultDayInMonth(int32_t eyear, int32_t month);
2023
2024	//-------------------------------------------------------------------------
2025	// Protected utility methods for use by subclasses. These are very handy
2026	// for implementing add, roll, and computeFields.
2027	//-------------------------------------------------------------------------
2028
2029	/**
2030	* Adjust the specified field so that it is within
2031	* the allowable range for the date to which this calendar is set.
2032	* For example, in a Gregorian calendar pinning the {@link #UCalendarDateFields DAY_OF_MONTH}
2033	* field for a calendar set to April 31 would cause it to be set
2034	* to April 30.
2035	* <p>
2036	* <b>Subclassing:</b>
2037	* <br>
2038	* This utility method is intended for use by subclasses that need to implement
2039	* their own overrides of {@link #roll roll} and {@link #add add}.
2040	* <p>
2041	* <b>Note:</b>
2042	* <code>pinField</code> is implemented in terms of
2043	* {@link #getActualMinimum getActualMinimum}
2044	* and {@link #getActualMaximum getActualMaximum}. If either of those methods uses
2045	* a slow, iterative algorithm for a particular field, it would be
2046	* unwise to attempt to call <code>pinField</code> for that field. If you
2047	* really do need to do so, you should override this method to do
2048	* something more efficient for that field.
2049	* <p>
2050	* @param field The calendar field whose value should be pinned.
2051	* @param status Output param set to failure code on function return
2052	* when this function fails.
2053	*
2054	* @see #getActualMinimum
2055	* @see #getActualMaximum
2056	* @stable ICU 2.0
2057	*/
2058	virtual void pinField(UCalendarDateFields field, UErrorCode& status);
2059
2060	/**
2061	* Return the week number of a day, within a period. This may be the week number in
2062	* a year or the week number in a month. Usually this will be a value >= 1, but if
2063	* some initial days of the period are excluded from week 1, because
2064	* {@link #getMinimalDaysInFirstWeek getMinimalDaysInFirstWeek} is > 1, then
2065	* the week number will be zero for those
2066	* initial days. This method requires the day number and day of week for some
2067	* known date in the period in order to determine the day of week
2068	* on the desired day.
2069	* <p>
2070	* <b>Subclassing:</b>
2071	* <br>
2072	* This method is intended for use by subclasses in implementing their
2073	* {@link #computeTime computeTime} and/or {@link #computeFields computeFields} methods.
2074	* It is often useful in {@link #getActualMinimum getActualMinimum} and
2075	* {@link #getActualMaximum getActualMaximum} as well.
2076	* <p>
2077	* This variant is handy for computing the week number of some other
2078	* day of a period (often the first or last day of the period) when its day
2079	* of the week is not known but the day number and day of week for some other
2080	* day in the period (e.g. the current date) <em>is</em> known.
2081	* <p>
2082	* @param desiredDay The {@link #UCalendarDateFields DAY_OF_YEAR} or
2083	* {@link #UCalendarDateFields DAY_OF_MONTH} whose week number is desired.
2084	* Should be 1 for the first day of the period.
2085	*
2086	* @param dayOfPeriod The {@link #UCalendarDateFields DAY_OF_YEAR}
2087	* or {@link #UCalendarDateFields DAY_OF_MONTH} for a day in the period whose
2088	* {@link #UCalendarDateFields DAY_OF_WEEK} is specified by the
2089	* <code>knownDayOfWeek</code> parameter.
2090	* Should be 1 for first day of period.
2091	*
2092	* @param dayOfWeek The {@link #UCalendarDateFields DAY_OF_WEEK} for the day
2093	* corresponding to the <code>knownDayOfPeriod</code> parameter.
2094	* 1-based with 1=Sunday.
2095	*
2096	* @return The week number (one-based), or zero if the day falls before
2097	* the first week because
2098	* {@link #getMinimalDaysInFirstWeek getMinimalDaysInFirstWeek}
2099	* is more than one.
2100	*
2101	* @stable ICU 2.8
2102	*/
2103	int32_t weekNumber(int32_t desiredDay, int32_t dayOfPeriod, int32_t dayOfWeek);
2104
2105
2106	#ifndef U_HIDE_INTERNAL_API
2107	/**
2108	* Return the week number of a day, within a period. This may be the week number in
2109	* a year, or the week number in a month. Usually this will be a value >= 1, but if
2110	* some initial days of the period are excluded from week 1, because
2111	* {@link #getMinimalDaysInFirstWeek getMinimalDaysInFirstWeek} is > 1,
2112	* then the week number will be zero for those
2113	* initial days. This method requires the day of week for the given date in order to
2114	* determine the result.
2115	* <p>
2116	* <b>Subclassing:</b>
2117	* <br>
2118	* This method is intended for use by subclasses in implementing their
2119	* {@link #computeTime computeTime} and/or {@link #computeFields computeFields} methods.
2120	* It is often useful in {@link #getActualMinimum getActualMinimum} and
2121	* {@link #getActualMaximum getActualMaximum} as well.
2122	* <p>
2123	* @param dayOfPeriod The {@link #UCalendarDateFields DAY_OF_YEAR} or
2124	* {@link #UCalendarDateFields DAY_OF_MONTH} whose week number is desired.
2125	* Should be 1 for the first day of the period.
2126	*
2127	* @param dayOfWeek The {@link #UCalendarDateFields DAY_OF_WEEK} for the day
2128	* corresponding to the <code>dayOfPeriod</code> parameter.
2129	* 1-based with 1=Sunday.
2130	*
2131	* @return The week number (one-based), or zero if the day falls before
2132	* the first week because
2133	* {@link #getMinimalDaysInFirstWeek getMinimalDaysInFirstWeek}
2134	* is more than one.
2135	* @internal
2136	*/
2137	inline int32_t weekNumber(int32_t dayOfPeriod, int32_t dayOfWeek);
2138
2139	/**
2140	* returns the local DOW, valid range 0..6
2141	* @internal
2142	*/
2143	int32_t getLocalDOW();
2144	#endif /* U_HIDE_INTERNAL_API */
2145
2146	private:
2147
2148	/**
2149	* The next available value for fStamp[]
2150	*/
2151	int32_t fNextStamp;// = MINIMUM_USER_STAMP;
2152
2153	/**
2154	* Recalculates the time stamp array (fStamp).
2155	* Resets fNextStamp to lowest next stamp value.
2156	*/
2157	void recalculateStamp();
2158
2159	/**
2160	* The current time set for the calendar.
2161	*/
2162	UDate fTime;
2163
2164	/**
2165	* @see #setLenient
2166	*/
2167	UBool fLenient;
2168
2169	/**
2170	* Time zone affects the time calculation done by Calendar. Calendar subclasses use
2171	* the time zone data to produce the local time. Always set; never NULL.
2172	*/
2173	TimeZone* fZone;
2174
2175	/**
2176	* Option for repeated wall time
2177	* @see #setRepeatedWallTimeOption
2178	*/
2179	UCalendarWallTimeOption fRepeatedWallTime;
2180
2181	/**
2182	* Option for skipped wall time
2183	* @see #setSkippedWallTimeOption
2184	*/
2185	UCalendarWallTimeOption fSkippedWallTime;
2186
2187	/**
2188	* Both firstDayOfWeek and minimalDaysInFirstWeek are locale-dependent. They are
2189	* used to figure out the week count for a specific date for a given locale. These
2190	* must be set when a Calendar is constructed. For example, in US locale,
2191	* firstDayOfWeek is SUNDAY; minimalDaysInFirstWeek is 1. They are used to figure
2192	* out the week count for a specific date for a given locale. These must be set when
2193	* a Calendar is constructed.
2194	*/
2195	UCalendarDaysOfWeek fFirstDayOfWeek;
2196	uint8_t fMinimalDaysInFirstWeek;
2197	UCalendarDaysOfWeek fWeekendOnset;
2198	int32_t fWeekendOnsetMillis;
2199	UCalendarDaysOfWeek fWeekendCease;
2200	int32_t fWeekendCeaseMillis;
2201
2202	/**
2203	* Sets firstDayOfWeek and minimalDaysInFirstWeek. Called at Calendar construction
2204	* time.
2205	*
2206	* @param desiredLocale The given locale.
2207	* @param type The calendar type identifier, e.g: gregorian, buddhist, etc.
2208	* @param success Indicates the status of setting the week count data from
2209	* the resource for the given locale. Returns U_ZERO_ERROR if
2210	* constructed successfully.
2211	*/
2212	void setWeekData(const Locale& desiredLocale, const char *type, UErrorCode& success);
2213
2214	/**
2215	* Recompute the time and update the status fields isTimeSet
2216	* and areFieldsSet. Callers should check isTimeSet and only
2217	* call this method if isTimeSet is false.
2218	*
2219	* @param status Output param set to success/failure code on exit. If any value
2220	* previously set in the time field is invalid or restricted by
2221	* leniency, this will be set to an error status.
2222	*/
2223	void updateTime(UErrorCode& status);
2224
2225	/**
2226	* The Gregorian year, as computed by computeGregorianFields() and
2227	* returned by getGregorianYear().
2228	* @see #computeGregorianFields
2229	*/
2230	int32_t fGregorianYear;
2231
2232	/**
2233	* The Gregorian month, as computed by computeGregorianFields() and
2234	* returned by getGregorianMonth().
2235	* @see #computeGregorianFields
2236	*/
2237	int32_t fGregorianMonth;
2238
2239	/**
2240	* The Gregorian day of the year, as computed by
2241	* computeGregorianFields() and returned by getGregorianDayOfYear().
2242	* @see #computeGregorianFields
2243	*/
2244	int32_t fGregorianDayOfYear;
2245
2246	/**
2247	* The Gregorian day of the month, as computed by
2248	* computeGregorianFields() and returned by getGregorianDayOfMonth().
2249	* @see #computeGregorianFields
2250	*/
2251	int32_t fGregorianDayOfMonth;
2252
2253	/* calculations */
2254
2255	/**
2256	* Compute the Gregorian calendar year, month, and day of month from
2257	* the given Julian day. These values are not stored in fields, but in
2258	* member variables gregorianXxx. Also compute the DAY_OF_WEEK and
2259	* DOW_LOCAL fields.
2260	*/
2261	void computeGregorianAndDOWFields(int32_t julianDay, UErrorCode &ec);
2262
2263	protected:
2264
2265	/**
2266	* Compute the Gregorian calendar year, month, and day of month from the
2267	* Julian day. These values are not stored in fields, but in member
2268	* variables gregorianXxx. They are used for time zone computations and by
2269	* subclasses that are Gregorian derivatives. Subclasses may call this
2270	* method to perform a Gregorian calendar millis->fields computation.
2271	*/
2272	void computeGregorianFields(int32_t julianDay, UErrorCode &ec);
2273
2274	private:
2275
2276	/**
2277	* Compute the fields WEEK_OF_YEAR, YEAR_WOY, WEEK_OF_MONTH,
2278	* DAY_OF_WEEK_IN_MONTH, and DOW_LOCAL from EXTENDED_YEAR, YEAR,
2279	* DAY_OF_WEEK, and DAY_OF_YEAR. The latter fields are computed by the
2280	* subclass based on the calendar system.
2281	*
2282	* <p>The YEAR_WOY field is computed simplistically. It is equal to YEAR
2283	* most of the time, but at the year boundary it may be adjusted to YEAR-1
2284	* or YEAR+1 to reflect the overlap of a week into an adjacent year. In
2285	* this case, a simple increment or decrement is performed on YEAR, even
2286	* though this may yield an invalid YEAR value. For instance, if the YEAR
2287	* is part of a calendar system with an N-year cycle field CYCLE, then
2288	* incrementing the YEAR may involve incrementing CYCLE and setting YEAR
2289	* back to 0 or 1. This is not handled by this code, and in fact cannot be
2290	* simply handled without having subclasses define an entire parallel set of
2291	* fields for fields larger than or equal to a year. This additional
2292	* complexity is not warranted, since the intention of the YEAR_WOY field is
2293	* to support ISO 8601 notation, so it will typically be used with a
2294	* proleptic Gregorian calendar, which has no field larger than a year.
2295	*/
2296	void computeWeekFields(UErrorCode &ec);
2297
2298
2299	/**
2300	* Ensure that each field is within its valid range by calling {@link
2301	* #validateField(int, int&)} on each field that has been set. This method
2302	* should only be called if this calendar is not lenient.
2303	* @see #isLenient
2304	* @see #validateField(int, int&)
2305	*/
2306	void validateFields(UErrorCode &status);
2307
2308	/**
2309	* Validate a single field of this calendar given its minimum and
2310	* maximum allowed value. If the field is out of range,
2311	* <code>U_ILLEGAL_ARGUMENT_ERROR</code> will be set. Subclasses may
2312	* use this method in their implementation of {@link
2313	* #validateField(int, int&)}.
2314	*/
2315	void validateField(UCalendarDateFields field, int32_t min, int32_t max, UErrorCode& status);
2316
2317	protected:
2318	#ifndef U_HIDE_INTERNAL_API
2319	/**
2320	* Convert a quasi Julian date to the day of the week. The Julian date used here is
2321	* not a true Julian date, since it is measured from midnight, not noon. Return
2322	* value is one-based.
2323	*
2324	* @param julian The given Julian date number.
2325	* @return Day number from 1..7 (SUN..SAT).
2326	* @internal
2327	*/
2328	static uint8_t julianDayToDayOfWeek(double julian);
2329	#endif /* U_HIDE_INTERNAL_API */
2330
2331	private:
2332	char validLocale[ULOC_FULLNAME_CAPACITY];
2333	char actualLocale[ULOC_FULLNAME_CAPACITY];
2334
2335	public:
2336	#if !UCONFIG_NO_SERVICE
2337	/**
2338	* INTERNAL FOR 2.6 -- Registration.
2339	*/
2340
2341	#ifndef U_HIDE_INTERNAL_API
2342	/**
2343	* Return a StringEnumeration over the locales available at the time of the call,
2344	* including registered locales.
2345	* @return a StringEnumeration over the locales available at the time of the call
2346	* @internal
2347	*/
2348	static StringEnumeration* getAvailableLocales(void);
2349
2350	/**
2351	* Register a new Calendar factory. The factory will be adopted.
2352	* INTERNAL in 2.6
2353	*
2354	* Because ICU may choose to cache Calendars internally, this must
2355	* be called at application startup, prior to any calls to
2356	* Calendar::createInstance to avoid undefined behavior.
2357	*
2358	* @param toAdopt the factory instance to be adopted
2359	* @param status the in/out status code, no special meanings are assigned
2360	* @return a registry key that can be used to unregister this factory
2361	* @internal
2362	*/
2363	static URegistryKey registerFactory(ICUServiceFactory* toAdopt, UErrorCode& status);
2364
2365	/**
2366	* Unregister a previously-registered CalendarFactory using the key returned from the
2367	* register call. Key becomes invalid after a successful call and should not be used again.
2368	* The CalendarFactory corresponding to the key will be deleted.
2369	* INTERNAL in 2.6
2370	*
2371	* Because ICU may choose to cache Calendars internally, this should
2372	* be called during application shutdown, after all calls to
2373	* Calendar::createInstance to avoid undefined behavior.
2374	*
2375	* @param key the registry key returned by a previous call to registerFactory
2376	* @param status the in/out status code, no special meanings are assigned
2377	* @return true if the factory for the key was successfully unregistered
2378	* @internal
2379	*/
2380	static UBool unregister(URegistryKey key, UErrorCode& status);
2381	#endif /* U_HIDE_INTERNAL_API */
2382
2383	/**
2384	* Multiple Calendar Implementation
2385	* @internal
2386	*/
2387	friend class CalendarFactory;
2388
2389	/**
2390	* Multiple Calendar Implementation
2391	* @internal
2392	*/
2393	friend class CalendarService;
2394
2395	/**
2396	* Multiple Calendar Implementation
2397	* @internal
2398	*/
2399	friend class DefaultCalendarFactory;
2400	#endif /* !UCONFIG_NO_SERVICE */
2401
2402	/**
2403	* @return true if this calendar has a default century (i.e. 03 -> 2003)
2404	* @internal
2405	*/
2406	virtual UBool haveDefaultCentury() const = 0;
2407
2408	/**
2409	* @return the start of the default century, as a UDate
2410	* @internal
2411	*/
2412	virtual UDate defaultCenturyStart() const = 0;
2413	/**
2414	* @return the beginning year of the default century, as a year
2415	* @internal
2416	*/
2417	virtual int32_t defaultCenturyStartYear() const = 0;
2418
2419	/** Get the locale for this calendar object. You can choose between valid and actual locale.
2420	* @param type type of the locale we're looking for (valid or actual)
2421	* @param status error code for the operation
2422	* @return the locale
2423	* @stable ICU 2.8
2424	*/
2425	Locale getLocale(ULocDataLocaleType type, UErrorCode &status) const;
2426
2427	/**
2428	* @return The related Gregorian year; will be obtained by modifying the value
2429	* obtained by get from UCAL_EXTENDED_YEAR field
2430	* @internal
2431	*/
2432	virtual int32_t getRelatedYear(UErrorCode &status) const;
2433
2434	/**
2435	* @param year The related Gregorian year to set; will be modified as necessary then
2436	* set in UCAL_EXTENDED_YEAR field
2437	* @internal
2438	*/
2439	virtual void setRelatedYear(int32_t year);
2440
2441	#ifndef U_HIDE_INTERNAL_API
2442	/** Get the locale for this calendar object. You can choose between valid and actual locale.
2443	* @param type type of the locale we're looking for (valid or actual)
2444	* @param status error code for the operation
2445	* @return the locale
2446	* @internal
2447	*/
2448	const char* getLocaleID(ULocDataLocaleType type, UErrorCode &status) const;
2449	#endif /* U_HIDE_INTERNAL_API */
2450
2451	private:
2452	/**
2453	* Cast TimeZone used by this object to BasicTimeZone, or NULL if the TimeZone
2454	* is not an instance of BasicTimeZone.
2455	*/
2456	BasicTimeZone* getBasicTimeZone() const;
2457
2458	/**
2459	* Find the previous zone transition near the given time.
2460	* @param base The base time, inclusive
2461	* @param transitionTime Receives the result time
2462	* @param status The error status
2463	* @return true if a transition is found.
2464	*/
2465	UBool getImmediatePreviousZoneTransition(UDate base, UDate *transitionTime, UErrorCode& status) const;
2466
2467	public:
2468	#ifndef U_HIDE_INTERNAL_API
2469	/**
2470	* Creates a new Calendar from a Locale for the cache.
2471	* This method does not set the time or timezone in returned calendar.
2472	* @param locale the locale.
2473	* @param status any error returned here.
2474	* @return the new Calendar object with no time or timezone set.
2475	* @internal For ICU use only.
2476	*/
2477	static Calendar * U_EXPORT2 makeInstance(
2478	const Locale &locale, UErrorCode &status);
2479
2480	/**
2481	* Get the calendar type for given locale.
2482	* @param locale the locale
2483	* @param typeBuffer calendar type returned here
2484	* @param typeBufferSize The size of typeBuffer in bytes. If the type
2485	* can't fit in the buffer, this method sets status to
2486	* U_BUFFER_OVERFLOW_ERROR
2487	* @param status error, if any, returned here.
2488	* @internal For ICU use only.
2489	*/
2490	static void U_EXPORT2 getCalendarTypeFromLocale(
2491	const Locale &locale,
2492	char *typeBuffer,
2493	int32_t typeBufferSize,
2494	UErrorCode &status);
2495	#endif /* U_HIDE_INTERNAL_API */
2496	};
2497
2498	// -------------------------------------
2499
2500	inline Calendar*
2501	Calendar::createInstance(TimeZone* zone, UErrorCode& errorCode)
2502	{
2503	// since the Locale isn't specified, use the default locale
2504	return createInstance(zoneToAdopt: zone, aLocale: Locale::getDefault(), success&: errorCode);
2505	}
2506
2507	// -------------------------------------
2508
2509	inline void
2510	Calendar::roll(UCalendarDateFields field, UBool up, UErrorCode& status)
2511	{
2512	roll(field, amount: (int32_t)(up ? +1 : -1), status);
2513	}
2514
2515	#ifndef U_HIDE_DEPRECATED_API
2516	inline void
2517	Calendar::roll(EDateFields field, UBool up, UErrorCode& status)
2518	{
2519	roll(field: (UCalendarDateFields) field, up, status);
2520	}
2521	#endif /* U_HIDE_DEPRECATED_API */
2522
2523
2524	// -------------------------------------
2525
2526	/**
2527	* Fast method for subclasses. The caller must maintain fUserSetDSTOffset and
2528	* fUserSetZoneOffset, as well as the isSet[] array.
2529	*/
2530
2531	inline void
2532	Calendar::internalSet(UCalendarDateFields field, int32_t value)
2533	{
2534	fFields[field] = value;
2535	fStamp[field] = kInternallySet;
2536	fIsSet[field] = true; // Remove later
2537	}
2538
2539
2540	#ifndef U_HIDE_INTERNAL_API
2541	inline int32_t Calendar::weekNumber(int32_t dayOfPeriod, int32_t dayOfWeek)
2542	{
2543	return weekNumber(desiredDay: dayOfPeriod, dayOfPeriod, dayOfWeek);
2544	}
2545	#endif /* U_HIDE_INTERNAL_API */
2546
2547	U_NAMESPACE_END
2548
2549	#endif /* #if !UCONFIG_NO_FORMATTING */
2550
2551	#endif /* U_SHOW_CPLUSPLUS_API */
2552
2553	#endif // _CALENDAR
2554