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/*
* Copyright (C) {1997-1999}, International Business Machines Corporation and others. All Rights Reserved.
********************************************************************************
*
* File GREGOCAL.H
*
* Modification History:
*
* Date Name Description
* 04/22/97 aliu Overhauled header.
* 07/28/98 stephen Sync with JDK 1.2
* 09/04/98 stephen Re-sync with JDK 8/31 putback
* 09/14/98 stephen Changed type of kOneDay, kOneWeek to double.
* Fixed bug in roll()
* 10/15/99 aliu Fixed j31, incorrect WEEK_OF_YEAR computation.
* Added documentation of WEEK_OF_YEAR computation.
* 10/15/99 aliu Fixed j32, cannot set date to Feb 29 2000 AD.
* {JDK bug 4210209 4209272}
********************************************************************************
*/
#ifndef GREGOCAL_H
#define GREGOCAL_H
#include "unicode/calendar.h"
U_NAMESPACE_BEGIN
/**
* Concrete class which provides the standard calendar used by most of the world.
* <P>
* The standard (Gregorian) calendar has 2 eras, BC and AD.
* <P>
* This implementation handles a single discontinuity, which corresponds by default to
* the date the Gregorian calendar was originally instituted (October 15, 1582). Not all
* countries adopted the Gregorian calendar then, so this cutover date may be changed by
* the caller.
* <P>
* Prior to the institution of the Gregorian Calendar, New Year's Day was March 25. To
* avoid confusion, this Calendar always uses January 1. A manual adjustment may be made
* if desired for dates that are prior to the Gregorian changeover and which fall
* between January 1 and March 24.
*
* <p>Values calculated for the <code>WEEK_OF_YEAR</code> field range from 1 to
* 53. Week 1 for a year is the first week that contains at least
* <code>getMinimalDaysInFirstWeek()</code> days from that year. It thus
* depends on the values of <code>getMinimalDaysInFirstWeek()</code>,
* <code>getFirstDayOfWeek()</code>, and the day of the week of January 1.
* Weeks between week 1 of one year and week 1 of the following year are
* numbered sequentially from 2 to 52 or 53 (as needed).
*
* <p>For example, January 1, 1998 was a Thursday. If
* <code>getFirstDayOfWeek()</code> is <code>MONDAY</code> and
* <code>getMinimalDaysInFirstWeek()</code> is 4 (these are the values
* reflecting ISO 8601 and many national standards), then week 1 of 1998 starts
* on December 29, 1997, and ends on January 4, 1998. If, however,
* <code>getFirstDayOfWeek()</code> is <code>SUNDAY</code>, then week 1 of 1998
* starts on January 4, 1998, and ends on January 10, 1998; the first three days
* of 1998 then are part of week 53 of 1997.
*
* <p>Example for using GregorianCalendar:
* <pre>
* \code
* // get the supported ids for GMT-08:00 (Pacific Standard Time)
* int32_t idsCount;
* const UnicodeString** ids = TimeZone::createAvailableIDs(-8 * 60 * 60 * 1000, idsCount);
* // if no ids were returned, something is wrong. get out.
* if (idsCount == 0) {
* return;
* }
*
* // begin output
* cout << "Current Time" << endl;
*
* // create a Pacific Standard Time time zone
* SimpleTimeZone* pdt = new SimpleTimeZone(-8 * 60 * 60 * 1000, *(ids[0]));
*
* // set up rules for daylight savings time
* pdt->setStartRule(Calendar::APRIL, 1, Calendar::SUNDAY, 2 * 60 * 60 * 1000);
* pdt->setEndRule(Calendar::OCTOBER, -1, Calendar::SUNDAY, 2 * 60 * 60 * 1000);
*
* // create a GregorianCalendar with the Pacific Daylight time zone
* // and the current date and time
* UErrorCode success = U_ZERO_ERROR;
* Calendar* calendar = new GregorianCalendar( pdt, success );
*
* // print out a bunch of interesting things
* cout << "ERA: " << calendar->get( Calendar::ERA, success ) << endl;
* cout << "YEAR: " << calendar->get( Calendar::YEAR, success ) << endl;
* cout << "MONTH: " << calendar->get( Calendar::MONTH, success ) << endl;
* cout << "WEEK_OF_YEAR: " << calendar->get( Calendar::WEEK_OF_YEAR, success ) << endl;
* cout << "WEEK_OF_MONTH: " << calendar->get( Calendar::WEEK_OF_MONTH, success ) << endl;
* cout << "DATE: " << calendar->get( Calendar::DATE, success ) << endl;
* cout << "DAY_OF_MONTH: " << calendar->get( Calendar::DAY_OF_MONTH, success ) << endl;
* cout << "DAY_OF_YEAR: " << calendar->get( Calendar::DAY_OF_YEAR, success ) << endl;
* cout << "DAY_OF_WEEK: " << calendar->get( Calendar::DAY_OF_WEEK, success ) << endl;
* cout << "DAY_OF_WEEK_IN_MONTH: " << calendar->get( Calendar::DAY_OF_WEEK_IN_MONTH, success ) << endl;
* cout << "AM_PM: " << calendar->get( Calendar::AM_PM, success ) << endl;
* cout << "HOUR: " << calendar->get( Calendar::HOUR, success ) << endl;
* cout << "HOUR_OF_DAY: " << calendar->get( Calendar::HOUR_OF_DAY, success ) << endl;
* cout << "MINUTE: " << calendar->get( Calendar::MINUTE, success ) << endl;
* cout << "SECOND: " << calendar->get( Calendar::SECOND, success ) << endl;
* cout << "MILLISECOND: " << calendar->get( Calendar::MILLISECOND, success ) << endl;
* cout << "ZONE_OFFSET: " << (calendar->get( Calendar::ZONE_OFFSET, success )/(60*60*1000)) << endl;
* cout << "DST_OFFSET: " << (calendar->get( Calendar::DST_OFFSET, success )/(60*60*1000)) << endl;
*
* cout << "Current Time, with hour reset to 3" << endl;
* calendar->clear(Calendar::HOUR_OF_DAY); // so doesn't override
* calendar->set(Calendar::HOUR, 3);
* cout << "ERA: " << calendar->get( Calendar::ERA, success ) << endl;
* cout << "YEAR: " << calendar->get( Calendar::YEAR, success ) << endl;
* cout << "MONTH: " << calendar->get( Calendar::MONTH, success ) << endl;
* cout << "WEEK_OF_YEAR: " << calendar->get( Calendar::WEEK_OF_YEAR, success ) << endl;
* cout << "WEEK_OF_MONTH: " << calendar->get( Calendar::WEEK_OF_MONTH, success ) << endl;
* cout << "DATE: " << calendar->get( Calendar::DATE, success ) << endl;
* cout << "DAY_OF_MONTH: " << calendar->get( Calendar::DAY_OF_MONTH, success ) << endl;
* cout << "DAY_OF_YEAR: " << calendar->get( Calendar::DAY_OF_YEAR, success ) << endl;
* cout << "DAY_OF_WEEK: " << calendar->get( Calendar::DAY_OF_WEEK, success ) << endl;
* cout << "DAY_OF_WEEK_IN_MONTH: " << calendar->get( Calendar::DAY_OF_WEEK_IN_MONTH, success ) << endl;
* cout << "AM_PM: " << calendar->get( Calendar::AM_PM, success ) << endl;
* cout << "HOUR: " << calendar->get( Calendar::HOUR, success ) << endl;
* cout << "HOUR_OF_DAY: " << calendar->get( Calendar::HOUR_OF_DAY, success ) << endl;
* cout << "MINUTE: " << calendar->get( Calendar::MINUTE, success ) << endl;
* cout << "SECOND: " << calendar->get( Calendar::SECOND, success ) << endl;
* cout << "MILLISECOND: " << calendar->get( Calendar::MILLISECOND, success ) << endl;
* cout << "ZONE_OFFSET: " << (calendar->get( Calendar::ZONE_OFFSET, success )/(60*60*1000)) << endl; // in hours
* cout << "DST_OFFSET: " << (calendar->get( Calendar::DST_OFFSET, success )/(60*60*1000)) << endl; // in hours
*
* delete[] ids;
* delete calendar; // also deletes pdt
* \endcode
* </pre>
* @stable
*/
class U_I18N_API GregorianCalendar: public Calendar {
public:
/**
* Useful constants for GregorianCalendar and TimeZone.
* @stable
*/
enum EEras {
BC,
AD
};
/**
* Constructs a default GregorianCalendar using the current time in the default time
* zone with the default locale.
*
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(UErrorCode& success);
/**
* Constructs a GregorianCalendar based on the current time in the given time zone
* with the default locale. Clients are no longer responsible for deleting the given
* time zone object after it's adopted.
*
* @param zoneToAdopt The given timezone.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(TimeZone* zoneToAdopt, UErrorCode& success);
/**
* Constructs a GregorianCalendar based on the current time in the given time zone
* with the default locale.
*
* @param zone The given timezone.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(const TimeZone& zone, UErrorCode& success);
/**
* Constructs a GregorianCalendar based on the current time in the default time zone
* with the given locale.
*
* @param aLocale The given locale.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(const Locale& aLocale, UErrorCode& success);
/**
* Constructs a GregorianCalendar based on the current time in the given time zone
* with the given locale. Clients are no longer responsible for deleting the given
* time zone object after it's adopted.
*
* @param zoneToAdopt The given timezone.
* @param aLocale The given locale.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(TimeZone* zoneToAdopt, const Locale& aLocale, UErrorCode& success);
/**
* Constructs a GregorianCalendar based on the current time in the given time zone
* with the given locale.
*
* @param zone The given timezone.
* @param aLocale The given locale.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(const TimeZone& zone, const Locale& aLocale, UErrorCode& success);
/**
* Constructs a GregorianCalendar with the given AD date set in the default time
* zone with the default locale.
*
* @param year The value used to set the YEAR time field in the calendar.
* @param month The value used to set the MONTH time field in the calendar. Month
* value is 0-based. e.g., 0 for January.
* @param date The value used to set the DATE time field in the calendar.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(int32_t year, int32_t month, int32_t date, UErrorCode& success);
/**
* Constructs a GregorianCalendar with the given AD date and time set for the
* default time zone with the default locale.
*
* @param year The value used to set the YEAR time field in the calendar.
* @param month The value used to set the MONTH time field in the calendar. Month
* value is 0-based. e.g., 0 for January.
* @param date The value used to set the DATE time field in the calendar.
* @param hour The value used to set the HOUR_OF_DAY time field in the calendar.
* @param minute The value used to set the MINUTE time field in the calendar.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, UErrorCode& success);
/**
* Constructs a GregorianCalendar with the given AD date and time set for the
* default time zone with the default locale.
*
* @param year The value used to set the YEAR time field in the calendar.
* @param month The value used to set the MONTH time field in the calendar. Month
* value is 0-based. e.g., 0 for January.
* @param date The value used to set the DATE time field in the calendar.
* @param hour The value used to set the HOUR_OF_DAY time field in the calendar.
* @param minute The value used to set the MINUTE time field in the calendar.
* @param second The value used to set the SECOND time field in the calendar.
* @param success Indicates the status of GregorianCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable
*/
GregorianCalendar(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, int32_t second, UErrorCode& success);
/**
* Destructor
* @stable
*/
virtual ~GregorianCalendar();
/**
* Copy constructor
* @stable
*/
GregorianCalendar(const GregorianCalendar& source);
/**
* Default assignment operator
* @stable
*/
GregorianCalendar& operator=(const GregorianCalendar& right);
/**
* Create and return a polymorphic copy of this calendar.
* @stable
*/
virtual Calendar* clone(void) const;
/**
* Sets the GregorianCalendar change date. This is the point when the switch from
* Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October
* 15, 1582. Previous to this time and date will be Julian dates.
*
* @param date The given Gregorian cutover date.
* @param success Output param set to success/failure code on exit.
* @stable
*/
void setGregorianChange(UDate date, UErrorCode& success);
/**
* Gets the Gregorian Calendar change date. This is the point when the switch from
* Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October
* 15, 1582. Previous to this time and date will be Julian dates.
*
* @return The Gregorian cutover time for this calendar.
* @stable
*/
UDate getGregorianChange(void) const;
/**
* Return true if the given year is a leap year. Determination of whether a year is
* a leap year is actually very complicated. We do something crude and mostly
* correct here, but for a real determination you need a lot of contextual
* information. For example, in Sweden, the change from Julian to Gregorian happened
* in a complex way resulting in missed leap years and double leap years between
* 1700 and 1753. Another example is that after the start of the Julian calendar in
* 45 B.C., the leap years did not regularize until 8 A.D. This method ignores these
* quirks, and pays attention only to the Julian onset date and the Gregorian
* cutover (which can be changed).
*
* @param year The given year.
* @return True if the given year is a leap year; false otherwise.
* @stable
*/
UBool isLeapYear(int32_t year) const;
/**
* Compares the equality of two GregorianCalendar objects. Objects of different
* subclasses are considered unequal. This is a strict equality test; see the
* documentation for Calendar::operator==().
*
* @param that The GregorianCalendar object to be compared with.
* @return True if the given GregorianCalendar is the same as this
* GregorianCalendar; false otherwise.
* @stable
*/
virtual UBool operator==(const Calendar& that) const;
/**
* Calendar override.
* Return true if another Calendar object is equivalent to this one. An equivalent
* Calendar will behave exactly as this one does, but may be set to a different time.
* @stable
*/
virtual UBool equivalentTo(const Calendar& other) const;
/**
* (Overrides Calendar) UDate Arithmetic function. Adds the specified (signed) amount
* of time to the given time field, based on the calendar's rules. For more
* information, see the documentation for Calendar::add().
*
* @param field The time field.
* @param amount The amount of date or time to be added to the field.
* @param status Output param set to success/failure code on exit. If any value
* previously set in the time field is invalid, this will be set to
* an error status.
* @stable
*/
virtual void add(EDateFields field, int32_t amount, UErrorCode& status);
/**
* (Overrides Calendar) Rolls up or down by the given amount in the specified field.
* For more information, see the documentation for Calendar::roll().
*
* @param field The time field.
* @param amount Indicates amount to roll.
* @param status Output param set to success/failure code on exit. If any value
* previously set in the time field is invalid, this will be set to
* an error status.
* @stable
*/
virtual void roll(EDateFields field, int32_t amount, UErrorCode& status);
/**
* (Overrides Calendar) Returns minimum value for the given field. e.g. for
* Gregorian DAY_OF_MONTH, 1.
* @stable
*/
virtual int32_t getMinimum(EDateFields field) const;
/**
* (Overrides Calendar) Returns maximum value for the given field. e.g. for
* Gregorian DAY_OF_MONTH, 31.
* @stable
*/
virtual int32_t getMaximum(EDateFields field) const;
/**
* (Overrides Calendar) Returns highest minimum value for the given field if varies.
* Otherwise same as getMinimum(). For Gregorian, no difference.
* @stable
*/
virtual int32_t getGreatestMinimum(EDateFields field) const;
/**
* (Overrides Calendar) Returns lowest maximum value for the given field if varies.
* Otherwise same as getMaximum(). For Gregorian DAY_OF_MONTH, 28.
* @stable
*/
virtual int32_t getLeastMaximum(EDateFields field) const;
/**
* Return the minimum value that this field could have, given the current date.
* For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum().
* @stable
*/
int32_t getActualMinimum(EDateFields field) const;
/**
* Return the maximum value that this field could have, given the current date.
* For example, with the date "Feb 3, 1997" and the DAY_OF_MONTH field, the actual
* maximum would be 28; for "Feb 3, 1996" it s 29. Similarly for a Hebrew calendar,
* for some years the actual maximum for MONTH is 12, and for others 13.
* @stable
*/
int32_t getActualMaximum(EDateFields field) const;
/**
* (Overrides Calendar) Return true if the current date for this Calendar is in
* Daylight Savings Time. Recognizes DST_OFFSET, if it is set.
*
* @param status Fill-in parameter which receives the status of this operation.
* @return True if the current date for this Calendar is in Daylight Savings Time,
* false, otherwise.
* @stable
*/
virtual UBool inDaylightTime(UErrorCode& status) const;
public:
/**
* Override Calendar Returns a unique class ID POLYMORPHICALLY. Pure virtual
* override. This method is to implement a simple version of RTTI, since not all C++
* compilers support genuine RTTI. Polymorphic operator==() and clone() methods call
* this method.
*
* @return The class ID for this object. All objects of a given class have the
* same class ID. Objects of other classes have different class IDs.
* @stable
*/
virtual UClassID getDynamicClassID(void) const { return (UClassID)&fgClassID; }
/**
* Return the class ID for this class. This is useful only for comparing to a return
* value from getDynamicClassID(). For example:
*
* Base* polymorphic_pointer = createPolymorphicObject();
* if (polymorphic_pointer->getDynamicClassID() ==
* Derived::getStaticClassID()) ...
*
* @return The class ID for all objects of this class.
* @stable
*/
static UClassID getStaticClassID(void) { return (UClassID)&fgClassID; }
protected:
/**
* (Overrides Calendar) Converts GMT as milliseconds to time field values.
* @stable
*/
virtual void computeFields(UErrorCode& status);
/**
* (Overrides Calendar) Converts Calendar's time field values to GMT as
* milliseconds.
*
* @param status Output param set to success/failure code on exit. If any value
* previously set in the time field is invalid, this will be set to
* an error status.
* @stable
*/
virtual void computeTime(UErrorCode& status);
private:
/**
* Return the ERA. We need a special method for this because the
* default ERA is AD, but a zero (unset) ERA is BC.
*/
int32_t internalGetEra() const;
int32_t monthLength(int32_t month) const;
int32_t monthLength(int32_t month, int32_t year) const;
int32_t yearLength(int32_t year) const;
int32_t yearLength(void) const;
/**
* After adjustments such as add(MONTH), add(YEAR), we don't want the
* month to jump around. E.g., we don't want Jan 31 + 1 month to go to Mar
* 3, we want it to go to Feb 28. Adjustments which might run into this
* problem call this method to retain the proper month.
*/
void pinDayOfMonth(void);
/**
* Return the day number with respect to the epoch. January 1, 1970 (Gregorian)
* is day zero.
*/
UDate getEpochDay(UErrorCode& status);
static double computeJulianDayOfYear(UBool isGregorian, int32_t year,
UBool& isLeap);
int32_t computeRelativeDOW() const;
int32_t computeRelativeDOW(double julianDay) const;
int32_t computeDOYfromWOY(double julianDayOfYear) const;
/**
* Compute the Julian day number under either the Gregorian or the
* Julian calendar, using the given year and the remaining fields.
* @param isGregorian if true, use the Gregorian calendar
* @param year the adjusted year number, with 0 indicating the
* year 1 BC, -1 indicating 2 BC, etc.
* @return the Julian day number
*/
double computeJulianDay(UBool isGregorian, int32_t year);
/**
* Compute the date-based fields given the milliseconds since the epoch start. Do
* not compute the time-based fields (HOUR, MINUTE, etc.).
*
* @param theTime the time in wall millis (either Standard or DST),
* whichever is in effect
* @param quick if true, only compute the ERA, YEAR, MONTH, DATE,
* DAY_OF_WEEK, and DAY_OF_YEAR.
*/
void timeToFields(UDate theTime, UBool quick, UErrorCode& status);
/**
* Return the week number of a day, within a period. This may be the week number in
* a year, or the week number in a month. Usually this will be a value >= 1, but if
* some initial days of the period are excluded from week 1, because
* minimalDaysInFirstWeek is > 1, then the week number will be zero for those
* initial days. Requires the day of week for the given date in order to determine
* the day of week of the first day of the period.
*
* @param date Day-of-year or day-of-month. Should be 1 for first day of period.
* @param day Day-of-week for given dayOfPeriod. 1-based with 1=Sunday.
* @return Week number, one-based, or zero if the day falls in part of the
* month before the first week, when there are days before the first
* week because the minimum days in the first week is more than one.
*/
int32_t weekNumber(int32_t date, int32_t day);
/**
* Validates the values of the set time fields. True if they're all valid.
*/
UBool validateFields(void) const;
/**
* Validates the value of the given time field. True if it's valid.
*/
UBool boundsCheck(int32_t value, EDateFields field) const;
/**
* Return the pseudo-time-stamp for two fields, given their
* individual pseudo-time-stamps. If either of the fields
* is unset, then the aggregate is unset. Otherwise, the
* aggregate is the later of the two stamps.
*/
int32_t aggregateStamp(int32_t stamp_a, int32_t stamp_b);
/**
* The point at which the Gregorian calendar rules are used, measured in
* milliseconds from the standard epoch. Default is October 15, 1582
* (Gregorian) 00:00:00 UTC, that is, October 4, 1582 (Julian) is followed
* by October 15, 1582 (Gregorian). This corresponds to Julian day number
* 2299161.
*/
// This is measured from the standard epoch, not in Julian Days.
UDate fGregorianCutover;
/**
* Midnight, local time (using this Calendar's TimeZone) at or before the
* gregorianCutover. This is a pure date value with no time of day or
* timezone component.
*/
UDate fNormalizedGregorianCutover;// = gregorianCutover;
/**
* The year of the gregorianCutover, with 0 representing
* 1 BC, -1 representing 2 BC, etc.
*/
int32_t fGregorianCutoverYear;// = 1582;
static const char fgClassID;
/**
* Converts time as milliseconds to Julian date. The Julian date used here is not a
* true Julian date, since it is measured from midnight, not noon.
*
* @param millis The given milliseconds.
* @return The Julian date number.
*/
static double millisToJulianDay(UDate millis);
/**
* Converts Julian date to time as milliseconds. The Julian date used here is not a
* true Julian date, since it is measured from midnight, not noon.
*
* @param julian The given Julian date number.
* @return Time as milliseconds.
*/
static UDate julianDayToMillis(double julian);
/**
* Convert a quasi Julian date to the day of the week. The Julian date used here is
* not a true Julian date, since it is measured from midnight, not noon. Return
* value is one-based.
*
* @return Day number from 1..7 (SUN..SAT).
*/
static uint8_t julianDayToDayOfWeek(double julian);
/**
* Divide two long integers, returning the floor of the quotient.
* <p>
* Unlike the built-in division, this is mathematically well-behaved.
* E.g., <code>-1/4</code> => 0
* but <code>floorDivide(-1,4)</code> => -1.
* @param numerator the numerator
* @param denominator a divisor which must be > 0
* @return the floor of the quotient.
*/
static double floorDivide(double numerator, double denominator);
/**
* Divide two integers, returning the floor of the quotient.
* <p>
* Unlike the built-in division, this is mathematically well-behaved.
* E.g., <code>-1/4</code> => 0
* but <code>floorDivide(-1,4)</code> => -1.
* @param numerator the numerator
* @param denominator a divisor which must be > 0
* @return the floor of the quotient.
*/
static int32_t floorDivide(int32_t numerator, int32_t denominator);
/**
* Divide two integers, returning the floor of the quotient, and
* the modulus remainder.
* <p>
* Unlike the built-in division, this is mathematically well-behaved.
* E.g., <code>-1/4</code> => 0 and <code>-1%4</code> => -1,
* but <code>floorDivide(-1,4)</code> => -1 with <code>remainder[0]</code> => 3.
* @param numerator the numerator
* @param denominator a divisor which must be > 0
* @param remainder an array of at least one element in which the value
* <code>numerator mod denominator</code> is returned. Unlike <code>numerator
* % denominator</code>, this will always be non-negative.
* @return the floor of the quotient.
*/
static int32_t floorDivide(int32_t numerator, int32_t denominator, int32_t remainder[]);
/**
* Divide two integers, returning the floor of the quotient, and
* the modulus remainder.
* <p>
* Unlike the built-in division, this is mathematically well-behaved.
* E.g., <code>-1/4</code> => 0 and <code>-1%4</code> => -1,
* but <code>floorDivide(-1,4)</code> => -1 with <code>remainder[0]</code> => 3.
* @param numerator the numerator
* @param denominator a divisor which must be > 0
* @param remainder an array of at least one element in which the value
* <code>numerator mod denominator</code> is returned. Unlike <code>numerator
* % denominator</code>, this will always be non-negative.
* @return the floor of the quotient.
*/
static int32_t floorDivide(double numerator, int32_t denominator, int32_t remainder[]);
};
inline uint8_t GregorianCalendar::julianDayToDayOfWeek(double julian)
{
// If julian is negative, then julian%7 will be negative, so we adjust
// accordingly. We add 1 because Julian day 0 is Monday.
int8_t dayOfWeek = (int8_t) uprv_fmod(julian + 1, 7);
uint8_t result = (uint8_t)(dayOfWeek + ((dayOfWeek < 0) ? (7 + SUNDAY) : SUNDAY));
return result;
}
U_NAMESPACE_END
#endif // _GREGOCAL
//eof