/* ******************************************************************************* * Copyright (C) 1997-2003, International Business Machines Corporation and * * others. All Rights Reserved. * ******************************************************************************* * * File GREGOCAL.CPP * * Modification History: * * Date Name Description * 02/05/97 clhuang Creation. * 03/28/97 aliu Made highly questionable fix to computeFields to * handle DST correctly. * 04/22/97 aliu Cleaned up code drastically. Added monthLength(). * Finished unimplemented parts of computeTime() for * week-based date determination. Removed quetionable * fix and wrote correct fix for computeFields() and * daylight time handling. Rewrote inDaylightTime() * and computeFields() to handle sensitive Daylight to * Standard time transitions correctly. * 05/08/97 aliu Added code review changes. Fixed isLeapYear() to * not cutover. * 08/12/97 aliu Added equivalentTo. Misc other fixes. Updated * add() from Java source. * 07/28/98 stephen Sync up with JDK 1.2 * 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. * 10/15/99 aliu Fixed j32, cannot set date to Feb 29 2000 AD. * {JDK bug 4210209 4209272} * 11/15/99 weiv Added YEAR_WOY and DOW_LOCAL computation * to timeToFields method, updated kMinValues, kMaxValues & kLeastMaxValues * 12/09/99 aliu Fixed j81, calculation errors and roll bugs * in year of cutover. * 01/24/2000 aliu Revised computeJulianDay for YEAR YEAR_WOY WOY. ******************************************************************************** */ #include "unicode/utypes.h" #include #if !UCONFIG_NO_FORMATTING #include "unicode/gregocal.h" #include "unicode/smpdtfmt.h" /* for the public field (!) SimpleDateFormat::fgSystemDefaultCentury */ #include "mutex.h" #include "uassert.h" // ***************************************************************************** // class GregorianCalendar // ***************************************************************************** static const int32_t kJan1_1JulianDay = 1721426; // January 1, year 1 (Gregorian) /** * Note that the Julian date used here is not a true Julian date, since * it is measured from midnight, not noon. This value is the Julian * day number of January 1, 1970 (Gregorian calendar) at noon UTC. [LIU] */ static const int32_t kEpochStartAsJulianDay = 2440588; // January 1, 1970 (Gregorian) static const int32_t kEpochYear = 1970; static const int32_t kNumDays[] = {0,31,59,90,120,151,181,212,243,273,304,334}; // 0-based, for day-in-year static const int32_t kLeapNumDays[] = {0,31,60,91,121,152,182,213,244,274,305,335}; // 0-based, for day-in-year static const int32_t kMonthLength[] = {31,28,31,30,31,30,31,31,30,31,30,31}; // 0-based static const int32_t kLeapMonthLength[] = {31,29,31,30,31,30,31,31,30,31,30,31}; // 0-based // Useful millisecond constants static const double kOneDay = U_MILLIS_PER_DAY; // 86,400,000 static const double kOneWeek = 7.0 * U_MILLIS_PER_DAY; // 604,800,000 // These numbers are 2^52 - 1, the largest allowable mantissa in a 64-bit double // with a 0 exponent. These are the absolute largest numbers for millis that // this calendar will handle reliably. It will work for larger values, however. // The problem is that, once the exponent is not 0, the calendar will jump. // When translated into a year, LATEST_SUPPORTED_MILLIS corresponds to 144,683 AD // and EARLIEST_SUPPORTED_MILLIS corresponds to 140,742 BC static const UDate EARLIEST_SUPPORTED_MILLIS = - 4503599627370495.0; static const UDate LATEST_SUPPORTED_MILLIS = 4503599627370495.0; /* * 
 *                            Greatest       Least 
 * Field name        Minimum   Minimum     Maximum     Maximum
 * ----------        -------   -------     -------     -------
 * ERA                     0         0           1           1
 * YEAR                    1         1      140742      144683
 * MONTH                   0         0          11          11
 * WEEK_OF_YEAR            1         1          52          53
 * WEEK_OF_MONTH           0         0           4           6
 * DAY_OF_MONTH            1         1          28          31
 * DAY_OF_YEAR             1         1         365         366
 * DAY_OF_WEEK             1         1           7           7
 * DAY_OF_WEEK_IN_MONTH   -1        -1           4           6
 * AM_PM                   0         0           1           1
 * HOUR                    0         0          11          11
 * HOUR_OF_DAY             0         0          23          23
 * MINUTE                  0         0          59          59
 * SECOND                  0         0          59          59
 * MILLISECOND             0         0         999         999
 * ZONE_OFFSET           -12*      -12*         12*         12*
 * DST_OFFSET              0         0           1*          1*
 * YEAR_WOY                1         1      140742      144683
 * DOW_LOCAL               1         1           7           7
 *
* (*) In units of one-hour */ static const int32_t kMinValues[] = { 0,1,0,1,0,1,1,1,-1,0,0,0,0,0,0,-12*U_MILLIS_PER_HOUR,0,1,1 }; static const int32_t kLeastMaxValues[] = { 1,140742,11,52,4,28,365,7,4,1,11,23,59,59,999,12*U_MILLIS_PER_HOUR,1*U_MILLIS_PER_HOUR,140742,7 }; static const int32_t kMaxValues[] = { 1,144683,11,53,6,31,366,7,6,1,11,23,59,59,999,12*U_MILLIS_PER_HOUR,1*U_MILLIS_PER_HOUR, 144683,7 }; U_NAMESPACE_BEGIN const char GregorianCalendar::fgClassID = 0; // Value is irrelevant // 00:00:00 UTC, October 15, 1582, expressed in ms from the epoch. // Note that only Italy and other Catholic countries actually // observed this cutover. Most other countries followed in // the next few centuries, some as late as 1928. [LIU] // in Java, -12219292800000L //const UDate GregorianCalendar::kPapalCutover = -12219292800000L; static const UDate kPapalCutover = (2299161.0 - kEpochStartAsJulianDay) * U_MILLIS_PER_DAY; // ------------------------------------- GregorianCalendar::GregorianCalendar(UErrorCode& status) : Calendar(TimeZone::createDefault(), Locale::getDefault(), status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { setTimeInMillis(getNow(), status); } // ------------------------------------- GregorianCalendar::GregorianCalendar(TimeZone* zone, UErrorCode& status) : Calendar(zone, Locale::getDefault(), status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { setTimeInMillis(getNow(), status); } // ------------------------------------- GregorianCalendar::GregorianCalendar(const TimeZone& zone, UErrorCode& status) : Calendar(zone, Locale::getDefault(), status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { setTimeInMillis(getNow(), status); } // ------------------------------------- GregorianCalendar::GregorianCalendar(const Locale& aLocale, UErrorCode& status) : Calendar(TimeZone::createDefault(), aLocale, status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { setTimeInMillis(getNow(), status); } // ------------------------------------- GregorianCalendar::GregorianCalendar(TimeZone* zone, const Locale& aLocale, UErrorCode& status) : Calendar(zone, aLocale, status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { setTimeInMillis(getNow(), status); } // ------------------------------------- GregorianCalendar::GregorianCalendar(const TimeZone& zone, const Locale& aLocale, UErrorCode& status) : Calendar(zone, aLocale, status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { setTimeInMillis(getNow(), status); } // ------------------------------------- GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date, UErrorCode& status) : Calendar(TimeZone::createDefault(), Locale::getDefault(), status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { set(UCAL_ERA, AD); set(UCAL_YEAR, year); set(UCAL_MONTH, month); set(UCAL_DATE, date); } // ------------------------------------- GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, UErrorCode& status) : Calendar(TimeZone::createDefault(), Locale::getDefault(), status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { set(UCAL_ERA, AD); set(UCAL_YEAR, year); set(UCAL_MONTH, month); set(UCAL_DATE, date); set(UCAL_HOUR_OF_DAY, hour); set(UCAL_MINUTE, minute); } // ------------------------------------- GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, int32_t second, UErrorCode& status) : Calendar(TimeZone::createDefault(), Locale::getDefault(), status), fGregorianCutover(kPapalCutover), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582) { set(UCAL_ERA, AD); set(UCAL_YEAR, year); set(UCAL_MONTH, month); set(UCAL_DATE, date); set(UCAL_HOUR_OF_DAY, hour); set(UCAL_MINUTE, minute); set(UCAL_SECOND, second); } // ------------------------------------- GregorianCalendar::~GregorianCalendar() { } // ------------------------------------- GregorianCalendar::GregorianCalendar(const GregorianCalendar &source) : Calendar(source), fGregorianCutover(source.fGregorianCutover), fNormalizedGregorianCutover(source.fNormalizedGregorianCutover), fGregorianCutoverYear(source.fGregorianCutoverYear) { } // ------------------------------------- Calendar* GregorianCalendar::clone() const { return new GregorianCalendar(*this); } // ------------------------------------- GregorianCalendar & GregorianCalendar::operator=(const GregorianCalendar &right) { if (this != &right) { Calendar::operator=(right); fGregorianCutover = right.fGregorianCutover; fNormalizedGregorianCutover = right.fNormalizedGregorianCutover; fGregorianCutoverYear = right.fGregorianCutoverYear; } return *this; } // ------------------------------------- UBool GregorianCalendar::isEquivalentTo(const Calendar& other) const { // Calendar override. return Calendar::isEquivalentTo(other) && fGregorianCutover == ((GregorianCalendar*)&other)->fGregorianCutover; } // ------------------------------------- void GregorianCalendar::setGregorianChange(UDate date, UErrorCode& status) { if (U_FAILURE(status)) return; fGregorianCutover = date; // Precompute two internal variables which we use to do the actual // cutover computations. These are the normalized cutover, which is the // midnight at or before the cutover, and the cutover year. The // normalized cutover is in pure date milliseconds; it contains no time // of day or timezone component, and it used to compare against other // pure date values. UDate cutoverDay = floorDivide(fGregorianCutover, kOneDay); fNormalizedGregorianCutover = cutoverDay * kOneDay; // Handle the rare case of numeric overflow. If the user specifies a // change of UDate(Long.MIN_VALUE), in order to get a pure Gregorian // calendar, then the epoch day is -106751991168, which when multiplied // by ONE_DAY gives 9223372036794351616 -- the negative value is too // large for 64 bits, and overflows into a positive value. We correct // this by using the next day, which for all intents is semantically // equivalent. if (cutoverDay < 0 && fNormalizedGregorianCutover > 0) { fNormalizedGregorianCutover = (cutoverDay + 1) * kOneDay; } // Normalize the year so BC values are represented as 0 and negative // values. GregorianCalendar *cal = new GregorianCalendar(getTimeZone(), status); /* test for NULL */ if (cal == 0) { status = U_MEMORY_ALLOCATION_ERROR; return; } if(U_FAILURE(status)) return; cal->setTime(date, status); fGregorianCutoverYear = cal->get(UCAL_YEAR, status); if (cal->get(UCAL_ERA, status) == BC) fGregorianCutoverYear = 1 - fGregorianCutoverYear; delete cal; } // ------------------------------------- UDate GregorianCalendar::getGregorianChange() const { return fGregorianCutover; } // ------------------------------------- UBool GregorianCalendar::isLeapYear(int32_t year) const { return (year >= fGregorianCutoverYear ? ((year%4 == 0) && ((year%100 != 0) || (year%400 == 0))) : // Gregorian (year%4 == 0)); // Julian } // ------------------------------------- /** * 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 given time as LOCAL milliseconds, not UTC. */ void GregorianCalendar::timeToFields(UDate theTime, UBool quick, UErrorCode& status) { if (U_FAILURE(status)) return; int32_t rawYear; int32_t year, yearOfWeekOfYear, month, date, dayOfWeek, locDayOfWeek, dayOfYear, era; UBool isLeap; // Compute the year, month, and day of month from the given millis if (theTime >= fNormalizedGregorianCutover) { // The Gregorian epoch day is zero for Monday January 1, year 1. double gregorianEpochDay = millisToJulianDay(theTime) - kJan1_1JulianDay; // Here we convert from the day number to the multiple radix // representation. We use 400-year, 100-year, and 4-year cycles. // For example, the 4-year cycle has 4 years + 1 leap day; giving // 1461 == 365*4 + 1 days. int32_t rem; int32_t n400 = floorDivide(gregorianEpochDay, 146097, rem); // 400-year cycle length int32_t n100 = floorDivide(rem, 36524, rem); // 100-year cycle length int32_t n4 = floorDivide(rem, 1461, rem); // 4-year cycle length int32_t n1 = floorDivide(rem, 365, rem); rawYear = 400*n400 + 100*n100 + 4*n4 + n1; dayOfYear = rem; // zero-based day of year if (n100 == 4 || n1 == 4) dayOfYear = 365; // Dec 31 at end of 4- or 400-yr cycle else ++rawYear; isLeap = ((rawYear&0x3) == 0) && // equiv. to (rawYear%4 == 0) (rawYear%100 != 0 || rawYear%400 == 0); // Gregorian day zero is a Monday dayOfWeek = (int32_t)uprv_fmod(gregorianEpochDay + 1, 7); } else { // The Julian epoch day (not the same as Julian Day) // is zero on Saturday December 30, 0 (Gregorian). double julianEpochDay = millisToJulianDay(theTime) - (kJan1_1JulianDay - 2); rawYear = (int32_t) floorDivide(4*julianEpochDay + 1464, 1461.0); // Compute the Julian calendar day number for January 1, rawYear double january1 = 365.0 * (rawYear - 1) + floorDivide((double)(rawYear - 1), 4.0); dayOfYear = (int32_t)(julianEpochDay - january1); // 0-based // Julian leap years occurred historically every 4 years starting // with 8 AD. Before 8 AD the spacing is irregular; every 3 years // from 45 BC to 9 BC, and then none until 8 AD. However, we don't // implement this historical detail; instead, we implement the // computatinally cleaner proleptic calendar, which assumes // consistent 4-year cycles throughout time. isLeap = ((rawYear & 0x3) == 0); // equiv. to (rawYear%4 == 0) // Julian calendar day zero is a Saturday dayOfWeek = (int32_t)uprv_fmod(julianEpochDay-1, 7); } // Common Julian/Gregorian calculation int32_t correction = 0; int32_t march1 = isLeap ? 60 : 59; // zero-based DOY for March 1 if (dayOfYear >= march1) correction = isLeap ? 1 : 2; month = (12 * (dayOfYear + correction) + 6) / 367; // zero-based month date = dayOfYear - (isLeap ? kLeapNumDays[month] : kNumDays[month]) + 1; // one-based DOM // Normalize day of week dayOfWeek += (dayOfWeek < 0) ? (UCAL_SUNDAY+7) : UCAL_SUNDAY; era = AD; year = rawYear; if (year < 1) { era = BC; year = 1 - year; } // Adjust the doy for the cutover year. Do this AFTER the above // computations using doy! [j81 - aliu] if (rawYear == fGregorianCutoverYear && theTime >= fNormalizedGregorianCutover) { dayOfYear -= 10; } // Calculate year of week of year internalSet(UCAL_ERA, era); internalSet(UCAL_YEAR, year); internalSet(UCAL_MONTH, month + UCAL_JANUARY); // 0-based internalSet(UCAL_DATE, date); internalSet(UCAL_DAY_OF_WEEK, dayOfWeek); internalSet(UCAL_DAY_OF_YEAR, ++dayOfYear); // Convert from 0-based to 1-based if (quick) return; yearOfWeekOfYear = year; // Compute the week of the year. Valid week numbers run from 1 to 52 // or 53, depending on the year, the first day of the week, and the // minimal days in the first week. Days at the start of the year may // fall into the last week of the previous year; days at the end of // the year may fall into the first week of the next year. int32_t relDow = (dayOfWeek + 7 - getFirstDayOfWeek()) % 7; // 0..6 int32_t relDowJan1 = (dayOfWeek - dayOfYear + 701 - getFirstDayOfWeek()) % 7; // 0..6 int32_t woy = (dayOfYear - 1 + relDowJan1) / 7; // 0..53 if ((7 - relDowJan1) >= getMinimalDaysInFirstWeek()) { ++woy; // Check to see if we are in the last week; if so, we need // to handle the case in which we are the first week of the // next year. int32_t lastDoy = yearLength(); int32_t lastRelDow = (relDow + lastDoy - dayOfYear) % 7; if (lastRelDow < 0) lastRelDow += 7; if (dayOfYear > 359 && // Fast check which eliminates most cases (6 - lastRelDow) >= getMinimalDaysInFirstWeek() && (dayOfYear + 7 - relDow) > lastDoy) { woy = 1; yearOfWeekOfYear++; } } else if (woy == 0) { // We are the last week of the previous year. int32_t prevDoy = dayOfYear + yearLength(rawYear - 1); woy = weekNumber(prevDoy, dayOfWeek); yearOfWeekOfYear--; } internalSet(UCAL_WEEK_OF_YEAR, woy); internalSet(UCAL_YEAR_WOY, yearOfWeekOfYear); internalSet(UCAL_WEEK_OF_MONTH, weekNumber(date, dayOfWeek)); internalSet(UCAL_DAY_OF_WEEK_IN_MONTH, (date-1) / 7 + 1); // Calculate localized day of week locDayOfWeek = dayOfWeek-getFirstDayOfWeek()+1; locDayOfWeek += (locDayOfWeek<1?7:0); internalSet(UCAL_DOW_LOCAL, locDayOfWeek); } // ------------------------------------- /** * 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 dayOfPeriod 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 GregorianCalendar::weekNumber(int32_t dayOfPeriod, int32_t dayOfWeek) { // Determine the day of the week of the first day of the period // in question (either a year or a month). Zero represents the // first day of the week on this calendar. int32_t periodStartDayOfWeek = (dayOfWeek - getFirstDayOfWeek() - dayOfPeriod + 1) % 7; if (periodStartDayOfWeek < 0) periodStartDayOfWeek += 7; // Compute the week number. Initially, ignore the first week, which // may be fractional (or may not be). We add periodStartDayOfWeek in // order to fill out the first week, if it is fractional. int32_t weekNo = (dayOfPeriod + periodStartDayOfWeek - 1)/7; // If the first week is long enough, then count it. If // the minimal days in the first week is one, or if the period start // is zero, we always increment weekNo. if ((7 - periodStartDayOfWeek) >= getMinimalDaysInFirstWeek()) ++weekNo; return weekNo; } // ------------------------------------- int32_t GregorianCalendar::monthLength(int32_t month) const { int32_t year = internalGet(UCAL_YEAR); if(internalGetEra() == BC) { year = 1 - year; } return monthLength(month, year); } // ------------------------------------- int32_t GregorianCalendar::monthLength(int32_t month, int32_t year) const { return isLeapYear(year) ? kLeapMonthLength[month] : kMonthLength[month]; } // ------------------------------------- int32_t GregorianCalendar::yearLength(int32_t year) const { return isLeapYear(year) ? 366 : 365; } // ------------------------------------- int32_t GregorianCalendar::yearLength() const { return isLeapYear(internalGet(UCAL_YEAR)) ? 366 : 365; } // ------------------------------------- /** * Overrides Calendar * Converts UTC as milliseconds to time field values. * The time is not * recomputed first; to recompute the time, then the fields, call the * complete method. * @see Calendar#complete */ void GregorianCalendar::computeFields(UErrorCode& ec) { if (U_FAILURE(ec)) { return; } // Compute local wall millis double millis = internalGetTime(); int32_t rawOffset, dstOffset; getTimeZone().getOffset(millis, FALSE, rawOffset, dstOffset, ec); millis += rawOffset + dstOffset; // Convert local wall millis to local wall fields. timeToFields(millis, FALSE, ec); // Compute time-of-day fields double days = uprv_floor(millis / kOneDay); int32_t millisInDay = (int32_t) (millis - (days * kOneDay)); // Fill in all time-related fields based on millisInDay. Call // internalSet() so as not to perturb flags. internalSet(UCAL_MILLISECOND, millisInDay % 1000); millisInDay /= 1000; internalSet(UCAL_SECOND, millisInDay % 60); millisInDay /= 60; internalSet(UCAL_MINUTE, millisInDay % 60); millisInDay /= 60; internalSet(UCAL_HOUR_OF_DAY, millisInDay); internalSet(UCAL_AM_PM, millisInDay / 12); // Assume AM == 0 internalSet(UCAL_HOUR, millisInDay % 12); internalSet(UCAL_ZONE_OFFSET, rawOffset); internalSet(UCAL_DST_OFFSET, dstOffset); // Careful here: We are manually setting the time stamps[] flags to // INTERNALLY_SET, so we must be sure that the above code actually does // set all these fields. for (int i=0; i monthLen) set(UCAL_DATE, monthLen); } // ------------------------------------- UBool GregorianCalendar::validateFields() const { for (int32_t field = 0; field < UCAL_FIELD_COUNT; field++) { // Ignore DATE and DAY_OF_YEAR which are handled below if (field != UCAL_DATE && field != UCAL_DAY_OF_YEAR && isSet((UCalendarDateFields)field) && ! boundsCheck(internalGet((UCalendarDateFields)field), (UCalendarDateFields)field)) return FALSE; } // Values differ in Least-Maximum and Maximum should be handled // specially. if (isSet(UCAL_DATE)) { int32_t date = internalGet(UCAL_DATE); if (date < getMinimum(UCAL_DATE) || date > monthLength(internalGet(UCAL_MONTH))) { return FALSE; } } if (isSet(UCAL_DAY_OF_YEAR)) { int32_t days = internalGet(UCAL_DAY_OF_YEAR); if (days < 1 || days > yearLength()) { return FALSE; } } // Handle DAY_OF_WEEK_IN_MONTH, which must not have the value zero. // We've checked against minimum and maximum above already. if (isSet(UCAL_DAY_OF_WEEK_IN_MONTH) && 0 == internalGet(UCAL_DAY_OF_WEEK_IN_MONTH)) { return FALSE; } return TRUE; } // ------------------------------------- UBool GregorianCalendar::boundsCheck(int32_t value, UCalendarDateFields field) const { return value >= getMinimum(field) && value <= getMaximum(field); } // ------------------------------------- UDate GregorianCalendar::getEpochDay(UErrorCode& status) { complete(status); // Divide by 1000 (convert to seconds) in order to prevent overflow when // dealing with UDate(Long.MIN_VALUE) and UDate(Long.MAX_VALUE). double wallSec = internalGetTime()/1000 + (internalGet(UCAL_ZONE_OFFSET) + internalGet(UCAL_DST_OFFSET))/1000; // {sfb} force conversion to double return uprv_trunc(wallSec / (kOneDay/1000.0)); //return floorDivide(wallSec, kOneDay/1000.0); } // ------------------------------------- int32_t GregorianCalendar::getGregorianYear(UErrorCode &status) const { int32_t year = (fStamp[UCAL_YEAR] != kUnset) ? internalGet(UCAL_YEAR) : kEpochYear; int32_t era = AD; if (fStamp[UCAL_ERA] != kUnset) { era = internalGet(UCAL_ERA); if (era == BC) year = 1 - year; // Even in lenient mode we disallow ERA values other than AD & BC else if (era != AD) { status = U_ILLEGAL_ARGUMENT_ERROR; return kEpochYear; } } return year; } void GregorianCalendar::computeTime(UErrorCode& status) { if (U_FAILURE(status)) return; if (! isLenient() && ! validateFields()) { status = U_ILLEGAL_ARGUMENT_ERROR; return; } // This function takes advantage of the fact that unset fields in // the time field list have a value of zero. // The year is either the YEAR or the epoch year. YEAR_WOY is // used only if WOY is the predominant field; see computeJulianDay. int32_t year = getGregorianYear(status); int32_t era = (year>0)?AD:BC; // calculate era from extended year. // First, use the year to determine whether to use the Gregorian or the // Julian calendar. If the year is not the year of the cutover, this // computation will be correct. But if the year is the cutover year, // this may be incorrect. In that case, assume the Gregorian calendar, // make the computation, and then recompute if the resultant millis // indicate the wrong calendar has been assumed. // A date such as Oct. 10, 1582 does not exist in a Gregorian calendar // with the default changeover of Oct. 15, 1582, since in such a // calendar Oct. 4 (Julian) is followed by Oct. 15 (Gregorian). This // algorithm will interpret such a date using the Julian calendar, // yielding Oct. 20, 1582 (Gregorian). UBool isGregorian = year >= fGregorianCutoverYear; double julianDay = computeJulianDay(isGregorian, year); double millis = julianDayToMillis(julianDay); // The following check handles portions of the cutover year BEFORE the // cutover itself happens. The check for the julianDate number is for a // rare case; it's a hardcoded number, but it's efficient. The given // Julian day number corresponds to Dec 3, 292269055 BC, which // corresponds to millis near Long.MIN_VALUE. The need for the check // arises because for extremely negative Julian day numbers, the millis // actually overflow to be positive values. Without the check, the // initial date is interpreted with the Gregorian calendar, even when // the cutover doesn't warrant it. if (isGregorian != (millis >= fNormalizedGregorianCutover) && julianDay != -106749550580.0) { // See above julianDay = computeJulianDay(!isGregorian, year); millis = julianDayToMillis(julianDay); } // Do the time portion of the conversion. int32_t millisInDay = 0; // Find the best set of fields specifying the time of day. There // are only two possibilities here; the HOUR_OF_DAY or the // AM_PM and the HOUR. int32_t hourOfDayStamp = fStamp[UCAL_HOUR_OF_DAY]; int32_t hourStamp = fStamp[UCAL_HOUR]; int32_t bestStamp = (hourStamp > hourOfDayStamp) ? hourStamp : hourOfDayStamp; // Hours if (bestStamp != kUnset) { if (bestStamp == hourOfDayStamp) // Don't normalize here; let overflow bump into the next period. // This is consistent with how we handle other fields. millisInDay += internalGet(UCAL_HOUR_OF_DAY); else { // Don't normalize here; let overflow bump into the next period. // This is consistent with how we handle other fields. millisInDay += internalGet(UCAL_HOUR); millisInDay += 12 * internalGet(UCAL_AM_PM); // Default works for unset AM_PM } } // We use the fact that unset == 0; we start with millisInDay // == HOUR_OF_DAY. millisInDay *= 60; millisInDay += internalGet(UCAL_MINUTE); // now have minutes millisInDay *= 60; millisInDay += internalGet(UCAL_SECOND); // now have seconds millisInDay *= 1000; millisInDay += internalGet(UCAL_MILLISECOND); // now have millis // Compute local wall millis millis += millisInDay; // Compute the time zone offset and DST offset. There are two // potential ambiguities here. We'll assume a 2:00 am (wall time) // switchover time for discussion purposes here. // 1. The transition into DST. Here, a designated time of 2:00 am // - 2:59 am can be in standard or in DST depending. However, // 2:00 am is an invalid representation (the representation // jumps from 1:59:59 am Std to 3:00:00 am DST). We assume // standard time. // 2. The transition out of DST. Here, a designated time of 1:00 am // - 1:59 am can be in standard or DST. Both are valid // representations (the rep jumps from 1:59:59 DST to 1:00:00 // Std). Again, we assume standard time. // We use the TimeZone object, unless the user has explicitly set // the ZONE_OFFSET field; this signals us to use the fields for // raw and DST offset. int32_t rawOffset, dstOffset; if (fStamp[UCAL_ZONE_OFFSET] >= kMinimumUserStamp) { rawOffset = internalGet(UCAL_ZONE_OFFSET); dstOffset = internalGet(UCAL_DST_OFFSET); } else { getTimeZone().getOffset(millis, TRUE, rawOffset, dstOffset, status); } // Convert local wall millis to GMT millis internalSetTime(millis - rawOffset - dstOffset); } // ------------------------------------- /** * Compute the julian day number of the day BEFORE the first day of * January 1, year 1 of the given calendar. If julianDay == 0, it * specifies (Jan. 1, 1) - 1, in whatever calendar we are using (Julian * or Gregorian). */ double GregorianCalendar::computeJulianDayOfYear(UBool isGregorian, int32_t year, UBool& isLeap) { isLeap = year%4 == 0; int32_t y = year - 1; double julianDay = 365.0*y + floorDivide(y, 4) + (kJan1_1JulianDay - 3); if (isGregorian) { isLeap = isLeap && ((year%100 != 0) || (year%400 == 0)); // Add 2 because Gregorian calendar starts 2 days after Julian calendar julianDay += floorDivide(y, 400) - floorDivide(y, 100) + 2; } return julianDay; } /** * Compute the day of week, relative to the first day of week, from * 0..6, of the current DOW_LOCAL or DAY_OF_WEEK fields. This is * equivalent to get(DOW_LOCAL) - 1. */ int32_t GregorianCalendar::computeRelativeDOW() const { int32_t relDow = 0; if (fStamp[UCAL_DOW_LOCAL] > fStamp[UCAL_DAY_OF_WEEK]) { relDow = internalGet(UCAL_DOW_LOCAL) - 1; // 1-based } else if (fStamp[UCAL_DAY_OF_WEEK] != kUnset) { relDow = internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek(); if (relDow < 0) relDow += 7; } return relDow; } /** * Compute the day of week, relative to the first day of week, * from 0..6 of the given julian day. */ int32_t GregorianCalendar::computeRelativeDOW(double julianDay) const { int32_t relDow = julianDayToDayOfWeek(julianDay) - getFirstDayOfWeek(); if (relDow < 0) { relDow += 7; } return relDow; } /** * Compute the DOY using the WEEK_OF_YEAR field and the julian day * of the day BEFORE January 1 of a year (a return value from * computeJulianDayOfYear). */ int32_t GregorianCalendar::computeDOYfromWOY(double julianDayOfYear) const { // Compute DOY from day of week plus week of year // Find the day of the week for the first of this year. This // is zero-based, with 0 being the locale-specific first day of // the week. Add 1 to get first day of year. int32_t fdy = computeRelativeDOW(julianDayOfYear + 1); return // Compute doy of first (relative) DOW of WOY 1 (((7 - fdy) < getMinimalDaysInFirstWeek()) ? (8 - fdy) : (1 - fdy)) // Adjust for the week number. + (7 * (internalGet(UCAL_WEEK_OF_YEAR) - 1)) // Adjust for the DOW + computeRelativeDOW(); } double GregorianCalendar::computeJulianDay(UBool isGregorian, int32_t year) { // Assumes 'year' is gregorian. // Find the most recent set of fields specifying the day within // the year. These may be any of the following combinations: // MONTH* + DAY_OF_MONTH* // MONTH* + WEEK_OF_MONTH* + DAY_OF_WEEK // MONTH* + DAY_OF_WEEK_IN_MONTH* + DAY_OF_WEEK // DAY_OF_YEAR* // WEEK_OF_YEAR* + DAY_OF_WEEK* // WEEK_OF_YEAR* + DOW_LOCAL // We look for the most recent of the fields marked thus*. If other // fields are missing, we use their default values, which are those of // the epoch start, or in the case of DAY_OF_WEEK, the first day in // the week. int32_t monthStamp = fStamp[UCAL_MONTH]; int32_t domStamp = fStamp[UCAL_DATE]; int32_t womStamp = fStamp[UCAL_WEEK_OF_MONTH]; int32_t dowimStamp = fStamp[UCAL_DAY_OF_WEEK_IN_MONTH]; int32_t doyStamp = fStamp[UCAL_DAY_OF_YEAR]; int32_t woyStamp = fStamp[UCAL_WEEK_OF_YEAR]; UBool isLeap; double julianDay; int32_t bestStamp = (monthStamp > domStamp) ? monthStamp : domStamp; if (womStamp > bestStamp) bestStamp = womStamp; if (dowimStamp > bestStamp) bestStamp = dowimStamp; if (doyStamp > bestStamp) bestStamp = doyStamp; if (woyStamp >= bestStamp) { // Note use of >= here, rather than >. We will see woy == // best if (a) all stamps are unset, in which case the // specific handling of unset will be used below, or (b) all // stamps are kInternallySet. In the latter case we want to // use the YEAR_WOY if it is newer. if (fStamp[UCAL_YEAR_WOY] > fStamp[UCAL_YEAR]) { year = internalGet(UCAL_YEAR_WOY); if (fStamp[UCAL_ERA] != kUnset && internalGet(UCAL_ERA) == BC) { year = 1 - year; } // Only the WOY algorithm correctly handles YEAR_WOY, so // force its use by making its stamp the most recent. // This only affects the situation in which all stamps are // equal (see above). bestStamp = ++woyStamp; } else if (woyStamp > bestStamp) { // The WOY stamp is not only equal to, but newer than any // other stamp. This means the WOY has been explicitly // set, and will be used for computation. bestStamp = woyStamp; if (fStamp[UCAL_YEAR_WOY] != kUnset && fStamp[UCAL_YEAR_WOY] >= fStamp[UCAL_YEAR]) { // The YEAR_WOY is set, and is not superceded by the // YEAR; use it. year = internalGet(UCAL_YEAR_WOY); } /* At this point we cannot avoid using the WEEK_OF_YEAR together * with the YEAR field, since the YEAR_WOY is unavailable. Our goal * is round-trip field integrity. We cannot guarantee round-trip * time integrity because the YEAR + WOY combination may be * ambiguous; consider a calendar with MDFW 3 and FDW Sunday. YEAR * 1997 + WOY 1 + DOW Wednesday specifies two days: Jan 1 1997, and * Dec 31 1997. However, we can guarantee that the YEAR fields, as * set, will remain unchanged. * * In general, YEAR and YEAR_WOY are equal, but at the ends of the * years, the YEAR and YEAR_WOY can differ by one. To detect this * in WOY 1, we look at the position of WOY 1. If it extends into * the previous year, then we check the DOW and see if it falls in * the previous year. If so, we increment the year. This allows us * to have round-trip integrity on the YEAR field. * * If the WOY is >= 52, then we do an intial computation of the DOY * for the current year. If this exceeds the length of this year, * we decrement the year. Again, this provides round-trip integrity * on the YEAR field. - aliu */ else if (internalGet(UCAL_WEEK_OF_YEAR) == 1) { // YEAR_WOY has not been set, so we must use the YEAR. // Since WOY computations rely on the YEAR_WOY, not the // YEAR, we must guess at its value. It is usually equal // to the YEAR, but may be one greater in WOY 1, and may // be one less in WOY >= 52. Note that YEAR + WOY is // ambiguous (YEAR_WOY + WOY is not). // FDW = Mon, MDFW = 2, Mon Dec 27 1999, WOY 1, YEAR_WOY 2000 // Find out where WOY 1 falls; some of it may extend // into the previous year. If so, and if the DOW is // one of those days, then increment the YEAR_WOY. julianDay = computeJulianDayOfYear(isGregorian, year, isLeap); int32_t fdy = computeRelativeDOW(1 + julianDay); int32_t doy = (((7 - fdy) < getMinimalDaysInFirstWeek()) ? (8 - fdy) : (1 - fdy)); if (doy < 1) { // Some of WOY 1 for YEAR year extends into YEAR // year-1 if doy < 1. doy == 0 -- 1 day of WOY 1 // in previous year; doy == -1 -- 2 days, etc. // Compute the day of week, relative to the first day of week, // from 0..6. int32_t relDow = computeRelativeDOW(); // Range of days that are in YEAR year (as opposed // to YEAR year-1) are DOY == 1..6+doy. Range of // days of the week in YEAR year are fdy..fdy + 5 // + doy. These are relative DOWs. if ((relDow < fdy) || (relDow > (fdy + 5 + doy))) { ++year; } } } else if (internalGet(UCAL_WEEK_OF_YEAR) >= 52) { // FDW = Mon, MDFW = 4, Sat Jan 01 2000, WOY 52, YEAR_WOY 1999 julianDay = computeJulianDayOfYear(isGregorian, year, isLeap); if (computeDOYfromWOY(julianDay) > yearLength(year)) { --year; } // It's tempting to take our julianDay and DOY here, in an else // clause, and return them, since they are correct. However, // this neglects the cutover adjustment, and it's easier to // maintain the code if everything goes through the same control // path below. - aliu } } } // The following if() clause checks if the month field // predominates. This set of computations must be done BEFORE // using the year, since the year value may be adjusted here. UBool useMonth = FALSE; int32_t month = 0; // SRL getDefaultMonth ? if (bestStamp != kUnset && (bestStamp == monthStamp || bestStamp == domStamp || bestStamp == womStamp || bestStamp == dowimStamp)) { useMonth = TRUE; // We have the month specified. Make it 0-based for the algorithm. month = (monthStamp != kUnset) ? internalGet(UCAL_MONTH) - UCAL_JANUARY : getDefaultMonthInYear(); // If the month is out of range, adjust it into range if (month < 0 || month > 11) { int32_t rem; year += floorDivide(month, 12, rem); month = rem; } } // Compute the julian day number of the day BEFORE the first day of // January 1, year 1 of the given calendar. If julianDay == 0, it // specifies (Jan. 1, 1) - 1, in whatever calendar we are using (Julian // or Gregorian). julianDay = computeJulianDayOfYear(isGregorian, year, isLeap); if (useMonth) { // Move julianDay to the day BEFORE the first of the month. julianDay += isLeap ? kLeapNumDays[month] : kNumDays[month]; int32_t date = 0; if (bestStamp == domStamp || bestStamp == monthStamp) { date = (domStamp != kUnset) ? internalGet(UCAL_DATE) : getDefaultDayInMonth(month); } else { // assert(bestStamp == womStamp || bestStamp == dowimStamp) // Compute from day of week plus week number or from the day of // week plus the day of week in month. The computations are // almost identical. // Find the day of the week for the first of this month. This // is zero-based, with 0 being the locale-specific first day of // the week. Add 1 to get first day of month. int32_t fdm = computeRelativeDOW(julianDay + 1); // Find the start of the first week. This will be a date from // 1..-6. It represents the locale-specific first day of the // week of the first day of the month, ignoring minimal days in // first week. date = 1 - fdm + ((fStamp[UCAL_DAY_OF_WEEK] != kUnset) ? ((internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek() + 7)%7) : 0); if (bestStamp == womStamp) { // Adjust for minimal days in first week. if ((7 - fdm) < getMinimalDaysInFirstWeek()) date += 7; // Now adjust for the week number. date += 7 * (internalGet(UCAL_WEEK_OF_MONTH) - 1); } else { // assert(bestStamp == dowimStamp) // Adjust into the month, if needed. if (date < 1) date += 7; // We are basing this on the day-of-week-in-month. The only // trickiness occurs if the day-of-week-in-month is // negative. int32_t dim = internalGet(UCAL_DAY_OF_WEEK_IN_MONTH); if (dim >= 0) { date += 7*(dim - 1); } else { // Move date to the last of this day-of-week in this // month, then back up as needed. If dim==-1, we don't // back up at all. If dim==-2, we back up once, etc. // Don't back up past the first of the given day-of-week // in this month. Note that we handle -2, -3, // etc. correctly, even though values < -1 are // technically disallowed. date += ((monthLength(internalGet(UCAL_MONTH), year) - date) / 7 + dim + 1) * 7; } } } julianDay += date; } else { // assert(bestStamp == doyStamp || bestStamp == woyStamp || // bestStamp == UNSET). In the last case we should use January 1. // No month, start with January 0 (day before Jan 1), then adjust. int32_t doy = 0; UBool doCutoverAdjustment = TRUE; if (bestStamp == kUnset) { //doy = 1; // For Gregorian the following will always be 1: kNumDays[UCAL_JANUARY] + 1 int32_t defMonth = getDefaultMonthInYear(); // 0 for gregorian int32_t defDay = getDefaultDayInMonth(defMonth); // 1 for gregorian doy = defDay + (isLeap ? kLeapNumDays[defMonth] : kNumDays[defMonth]); doCutoverAdjustment = FALSE; } else if (bestStamp == doyStamp) { doy = internalGet(UCAL_DAY_OF_YEAR); } else if (bestStamp == woyStamp) { doy = computeDOYfromWOY(julianDay); } // Adjust for cutover year [j81 - aliu] if (doCutoverAdjustment && year == fGregorianCutoverYear && isGregorian) { doy -= 10; } julianDay += doy; } return julianDay; } // ------------------------------------- double GregorianCalendar::millisToJulianDay(UDate millis) { return (double)kEpochStartAsJulianDay + floorDivide(millis, kOneDay); //return kEpochStartAsJulianDay + uprv_trunc(millis / kOneDay); } // ------------------------------------- UDate GregorianCalendar::julianDayToMillis(double julian) { return (UDate) ((julian - kEpochStartAsJulianDay) * (double) kOneDay); } // ------------------------------------- double GregorianCalendar::floorDivide(double numerator, double denominator) { return uprv_floor(numerator / denominator); } // ------------------------------------- int32_t GregorianCalendar::floorDivide(int32_t numerator, int32_t denominator) { // We do this computation in order to handle // a numerator of Long.MIN_VALUE correctly return (numerator >= 0) ? numerator / denominator : ((numerator + 1) / denominator) - 1; } // ------------------------------------- int32_t GregorianCalendar::floorDivide(int32_t numerator, int32_t denominator, int32_t& remainder) { if (numerator >= 0) { remainder = numerator % denominator; return numerator / denominator; } int32_t quotient = ((numerator + 1) / denominator) - 1; remainder = numerator - (quotient * denominator); return quotient; } // ------------------------------------- int32_t GregorianCalendar::floorDivide(double numerator, int32_t denominator, int32_t& remainder) { double quotient; if (numerator >= 0) { quotient = uprv_trunc(numerator / denominator); remainder = (int32_t)uprv_fmod(numerator, denominator); } else { quotient = uprv_trunc((numerator + 1) / denominator) - 1; remainder = (int32_t)(numerator - (quotient * denominator)); } if (quotient < INT32_MIN || quotient > INT32_MAX) { // Normalize out of range values. It doesn't matter what // we return for these cases; the data is wrong anyway. This // only occurs for years near 2,000,000,000 CE/BCE. quotient = 0.0; // Or whatever } return (int32_t)quotient; } // ------------------------------------- int32_t GregorianCalendar::aggregateStamp(int32_t stamp_a, int32_t stamp_b) { return (((stamp_a != kUnset && stamp_b != kUnset) ? uprv_max(stamp_a, stamp_b) : kUnset)); } // ------------------------------------- void GregorianCalendar::add(EDateFields field, int32_t amount, UErrorCode& status) { add((UCalendarDateFields) field, amount, status); } void GregorianCalendar::add(UCalendarDateFields field, int32_t amount, UErrorCode& status) { if (U_FAILURE(status)) return; if (amount == 0) return; // Do nothing! complete(status); if (field == UCAL_YEAR || field == UCAL_YEAR_WOY) { int32_t year = internalGet(field); int32_t era = internalGetEra(); year += (era == AD) ? amount : -amount; if (year > 0) set(field, year); else { // year <= 0 set(field, 1 - year); // if year == 0, you get 1 BC set(UCAL_ERA, (AD + BC) - era); } pinDayOfMonth(); } else if (field == UCAL_MONTH) { int32_t month = internalGet(UCAL_MONTH) + amount; if (month >= 0) { add(UCAL_YEAR, (int32_t) (month / 12), status); set(UCAL_MONTH, (int32_t) (month % 12)); } else { // month < 0 add(UCAL_YEAR, (int32_t) ((month + 1) / 12) - 1, status); month %= 12; if (month < 0) month += 12; set(UCAL_MONTH, UCAL_JANUARY + month); } pinDayOfMonth(); } else if (field == UCAL_ERA) { int32_t era = internalGet(UCAL_ERA) + amount; if (era < 0) era = 0; if (era > 1) era = 1; set(UCAL_ERA, era); } else { // We handle most fields here. The algorithm is to add a computed amount // of millis to the current millis. The only wrinkle is with DST -- if // the result of the add operation is to move from DST to Standard, or vice // versa, we need to adjust by an hour forward or back, respectively. // Otherwise you get weird effects in which the hour seems to shift when // you add to the DAY_OF_MONTH field, for instance. // We only adjust the DST for fields larger than an hour. For fields // smaller than an hour, we cannot adjust for DST without causing problems. // for instance, if you add one hour to April 5, 1998, 1:00 AM, in PST, // the time becomes "2:00 AM PDT" (an illegal value), but then the adjustment // sees the change and compensates by subtracting an hour. As a result the // time doesn't advance at all. // {sfb} do we want to use a double here, or a int32_t? // probably a double, since if we used a int32_t in the // WEEK_OF_YEAR clause below, if delta was greater than approx. // 7.1 we would reach the limit of a int32_t double delta = amount; UBool adjustDST = TRUE; switch (field) { case UCAL_WEEK_OF_YEAR: case UCAL_WEEK_OF_MONTH: case UCAL_DAY_OF_WEEK_IN_MONTH: delta *= 7 * 24 * 60 * 60 * 1000; // 7 days break; case UCAL_AM_PM: delta *= 12 * 60 * 60 * 1000; // 12 hrs break; case UCAL_DATE: // synonym of DAY_OF_MONTH case UCAL_DAY_OF_YEAR: case UCAL_DAY_OF_WEEK: case UCAL_DOW_LOCAL: delta *= 24 * 60 * 60 * 1000; // 1 day break; case UCAL_HOUR_OF_DAY: case UCAL_HOUR: delta *= 60 * 60 * 1000; // 1 hour adjustDST = FALSE; break; case UCAL_MINUTE: delta *= 60 * 1000; // 1 minute adjustDST = FALSE; break; case UCAL_SECOND: delta *= 1000; // 1 second adjustDST = FALSE; break; case UCAL_MILLISECOND: adjustDST = FALSE; break; case UCAL_ZONE_OFFSET: case UCAL_DST_OFFSET: default: status = U_ILLEGAL_ARGUMENT_ERROR; return; } // In order to keep the hour invariant (for fields where this is // appropriate), record the DST_OFFSET before and after the add() // operation. If it has changed, then adjust the millis to // compensate. int32_t dst = 0; int32_t hour = 0; if (adjustDST) { dst = get(UCAL_DST_OFFSET, status); hour = internalGet(UCAL_HOUR_OF_DAY); } setTimeInMillis(internalGetTime() + delta, status); if (adjustDST) { dst -= get(UCAL_DST_OFFSET, status); if (dst != 0) { // We have done an hour-invariant adjustment but the // DST offset has altered. We adjust millis to keep // the hour constant. In cases such as midnight after // a DST change which occurs at midnight, there is the // danger of adjusting into a different day. To avoid // this we make the adjustment only if it actually // maintains the hour. UDate t = internalGetTime(); setTimeInMillis(t + dst, status); if (get(UCAL_HOUR_OF_DAY, status) != hour) { setTimeInMillis(t, status); } } } } } // ------------------------------------- /** * Roll a field by a signed amount. * Note: This will be made public later. [LIU] */ void GregorianCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status) { roll((UCalendarDateFields) field, amount, status); } void GregorianCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) { if(U_FAILURE(status)) return; if (amount == 0) return; // Nothing to do int32_t min = 0, max = 0, gap; if (field >= 0 && field < UCAL_FIELD_COUNT) { complete(status); min = getMinimum(field); max = getMaximum(field); } /* Some of the fields require special handling to work in the month * containing the Gregorian cutover point. Do shared computations * for these fields here. [j81 - aliu] */ UBool inCutoverMonth = FALSE; int32_t cMonthLen=0; // 'c' for cutover; in days int32_t cDayOfMonth=0; // no discontinuity: [0, cMonthLen) double cMonthStart=0.0; // in ms if (field == UCAL_DATE || field == UCAL_WEEK_OF_MONTH) { max = monthLength(internalGet(UCAL_MONTH)); double t = internalGetTime(); // We subtract 1 from the DAY_OF_MONTH to make it zero-based, and an // additional 10 if we are after the cutover. Thus the monthStart // value will be correct iff we actually are in the cutover month. cDayOfMonth = internalGet(UCAL_DATE) - ((t >= fGregorianCutover) ? 10 : 0); cMonthStart = t - ((cDayOfMonth - 1) * kOneDay); // A month containing the cutover is 10 days shorter. if ((cMonthStart < fGregorianCutover) && (cMonthStart + (cMonthLen=(max-10))*kOneDay >= fGregorianCutover)) { inCutoverMonth = TRUE; } } switch (field) { case UCAL_ERA: case UCAL_YEAR: case UCAL_YEAR_WOY: case UCAL_AM_PM: case UCAL_MINUTE: case UCAL_SECOND: case UCAL_MILLISECOND: // These fields are handled simply, since they have fixed minima // and maxima. The field DAY_OF_MONTH is almost as simple. Other // fields are complicated, since the range within they must roll // varies depending on the date. break; case UCAL_HOUR: case UCAL_HOUR_OF_DAY: // Rolling the hour is difficult on the ONSET and CEASE days of // daylight savings. For example, if the change occurs at // 2 AM, we have the following progression: // ONSET: 12 Std -> 1 Std -> 3 Dst -> 4 Dst // CEASE: 12 Dst -> 1 Dst -> 1 Std -> 2 Std // To get around this problem we don't use fields; we manipulate // the time in millis directly. { // Assume min == 0 in calculations below UDate start = getTime(status); int32_t oldHour = internalGet(field); int32_t newHour = (oldHour + amount) % (max + 1); if(newHour < 0) newHour += max + 1; setTime(start + ((double)U_MILLIS_PER_HOUR * (newHour - oldHour)), status); return; } case UCAL_MONTH: // Rolling the month involves both pinning the final value to [0, 11] // and adjusting the DAY_OF_MONTH if necessary. We only adjust the // DAY_OF_MONTH if, after updating the MONTH field, it is illegal. // E.g., .roll(MONTH, 1) -> or . { int32_t mon = (internalGet(UCAL_MONTH) + amount) % 12; if (mon < 0) mon += 12; set(UCAL_MONTH, mon); // Keep the day of month in range. We don't want to spill over // into the next month; e.g., we don't want jan31 + 1 mo -> feb31 -> // mar3. // NOTE: We could optimize this later by checking for dom <= 28 // first. Do this if there appears to be a need. [LIU] int32_t monthLen = monthLength(mon); int32_t dom = internalGet(UCAL_DATE); if (dom > monthLen) set(UCAL_DATE, monthLen); return; } case UCAL_WEEK_OF_YEAR: { // Unlike WEEK_OF_MONTH, WEEK_OF_YEAR never shifts the day of the // week. However, rolling the week of the year can have seemingly // strange effects simply because the year of the week of year // may be different from the calendar year. For example, the // date Dec 28, 1997 is the first day of week 1 of 1998 (if // weeks start on Sunday and the minimal days in first week is // <= 3). int32_t woy = internalGet(UCAL_WEEK_OF_YEAR); // Get the ISO year, which matches the week of year. This // may be one year before or after the calendar year. int32_t isoYear = internalGet(UCAL_YEAR_WOY); int32_t isoDoy = internalGet(UCAL_DAY_OF_YEAR); if (internalGet(UCAL_MONTH) == UCAL_JANUARY) { if (woy >= 52) { isoDoy += yearLength(isoYear); } } else { if (woy == 1) { isoDoy -= yearLength(isoYear-1); } } woy += amount; // Do fast checks to avoid unnecessary computation: if (woy < 1 || woy > 52) { // Determine the last week of the ISO year. // We do this using the standard formula we use // everywhere in this file. If we can see that the // days at the end of the year are going to fall into // week 1 of the next year, we drop the last week by // subtracting 7 from the last day of the year. int32_t lastDoy = yearLength(isoYear); int32_t lastRelDow = (lastDoy - isoDoy + internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek()) % 7; if (lastRelDow < 0) lastRelDow += 7; if ((6 - lastRelDow) >= getMinimalDaysInFirstWeek()) lastDoy -= 7; int32_t lastWoy = weekNumber(lastDoy, lastRelDow + 1); woy = ((woy + lastWoy - 1) % lastWoy) + 1; } set(UCAL_WEEK_OF_YEAR, woy); set(UCAL_YEAR_WOY, isoYear); // make YEAR_WOY timestamp > YEAR timestamp return; } case UCAL_WEEK_OF_MONTH: { // This is tricky, because during the roll we may have to shift // to a different day of the week. For example: // s m t w r f s // 1 2 3 4 5 // 6 7 8 9 10 11 12 // When rolling from the 6th or 7th back one week, we go to the // 1st (assuming that the first partial week counts). The same // thing happens at the end of the month. // The other tricky thing is that we have to figure out whether // the first partial week actually counts or not, based on the // minimal first days in the week. And we have to use the // correct first day of the week to delineate the week // boundaries. // Here's our algorithm. First, we find the real boundaries of // the month. Then we discard the first partial week if it // doesn't count in this locale. Then we fill in the ends with // phantom days, so that the first partial week and the last // partial week are full weeks. We then have a nice square // block of weeks. We do the usual rolling within this block, // as is done elsewhere in this method. If we wind up on one of // the phantom days that we added, we recognize this and pin to // the first or the last day of the month. Easy, eh? // Another wrinkle: To fix jitterbug 81, we have to make all this // work in the oddball month containing the Gregorian cutover. // This month is 10 days shorter than usual, and also contains // a discontinuity in the days; e.g., the default cutover month // is Oct 1582, and goes from day of month 4 to day of month 15. // Normalize the DAY_OF_WEEK so that 0 is the first day of the week // in this locale. We have dow in 0..6. int32_t dow = internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek(); if (dow < 0) dow += 7; // Find the day of month, compensating for cutover discontinuity. int32_t dom = inCutoverMonth ? cDayOfMonth : internalGet(UCAL_DATE); // Find the day of the week (normalized for locale) for the first // of the month. int32_t fdm = (dow - dom + 1) % 7; if (fdm < 0) fdm += 7; // Get the first day of the first full week of the month, // including phantom days, if any. Figure out if the first week // counts or not; if it counts, then fill in phantom days. If // not, advance to the first real full week (skip the partial week). int32_t start; if ((7 - fdm) < getMinimalDaysInFirstWeek()) start = 8 - fdm; // Skip the first partial week else start = 1 - fdm; // This may be zero or negative // Get the day of the week (normalized for locale) for the last // day of the month. int32_t monthLen = inCutoverMonth ? cMonthLen : monthLength(internalGet(UCAL_MONTH)); int32_t ldm = (monthLen - dom + dow) % 7; // We know monthLen >= DAY_OF_MONTH so we skip the += 7 step here. // Get the limit day for the blocked-off rectangular month; that // is, the day which is one past the last day of the month, // after the month has already been filled in with phantom days // to fill out the last week. This day has a normalized DOW of 0. int32_t limit = monthLen + 7 - ldm; // Now roll between start and (limit - 1). gap = limit - start; int32_t newDom = (dom + amount*7 - start) % gap; if (newDom < 0) newDom += gap; newDom += start; // Finally, pin to the real start and end of the month. if (newDom < 1) newDom = 1; if (newDom > monthLen) newDom = monthLen; // Set the DAY_OF_MONTH. We rely on the fact that this field // takes precedence over everything else (since all other fields // are also set at this point). If this fact changes (if the // disambiguation algorithm changes) then we will have to unset // the appropriate fields here so that DAY_OF_MONTH is attended // to. // If we are in the cutover month, manipulate ms directly. Don't do // this in general because it doesn't work across DST boundaries // (details, details). This takes care of the discontinuity. if (inCutoverMonth) { setTimeInMillis(cMonthStart + (newDom-1)*kOneDay, status); } else { set(UCAL_DATE, newDom); } return; } case UCAL_DATE: if (inCutoverMonth) { // The default computation works except when the current month // contains the Gregorian cutover. We handle this special case // here. [j81 - aliu] double monthLen = cMonthLen * kOneDay; double msIntoMonth = uprv_fmod(internalGetTime() - cMonthStart + amount * kOneDay, monthLen); if (msIntoMonth < 0) { msIntoMonth += monthLen; } setTimeInMillis(cMonthStart + msIntoMonth, status); return; } else { max = monthLength(internalGet(UCAL_MONTH)); // ...else fall through to default computation } break; case UCAL_DAY_OF_YEAR: { // Roll the day of year using millis. Compute the millis for // the start of the year, and get the length of the year. double delta = amount * kOneDay; // Scale up from days to millis double min2 = internalGetTime() - (internalGet(UCAL_DAY_OF_YEAR) - 1) * kOneDay; int32_t yearLen = yearLength(); internalSetTime( uprv_fmod((internalGetTime() + delta - min2), (yearLen * kOneDay))); if (internalGetTime() < 0) internalSetTime( internalGetTime() + yearLen * kOneDay); setTimeInMillis(internalGetTime() + min2, status); return; } case UCAL_DAY_OF_WEEK: case UCAL_DOW_LOCAL: { // Roll the day of week using millis. Compute the millis for // the start of the week, using the first day of week setting. // Restrict the millis to [start, start+7days). double delta = amount * kOneDay; // Scale up from days to millis // Compute the number of days before the current day in this // week. This will be a value 0..6. int32_t leadDays = internalGet(field) - ((field == UCAL_DAY_OF_WEEK) ? getFirstDayOfWeek() : 1); if (leadDays < 0) leadDays += 7; double min2 = internalGetTime() - leadDays * kOneDay; internalSetTime(uprv_fmod((internalGetTime() + delta - min2), kOneWeek)); if (internalGetTime() < 0) internalSetTime(internalGetTime() + kOneWeek); setTimeInMillis(internalGetTime() + min2, status); return; } case UCAL_DAY_OF_WEEK_IN_MONTH: { // Roll the day of week in the month using millis. Determine // the first day of the week in the month, and then the last, // and then roll within that range. double delta = amount * kOneWeek; // Scale up from weeks to millis // Find the number of same days of the week before this one // in this month. int32_t preWeeks = (internalGet(UCAL_DATE) - 1) / 7; // Find the number of same days of the week after this one // in this month. int32_t postWeeks = (monthLength(internalGet(UCAL_MONTH)) - internalGet(UCAL_DATE)) / 7; // From these compute the min and gap millis for rolling. double min2 = internalGetTime() - preWeeks * kOneWeek; double gap2 = kOneWeek * (preWeeks + postWeeks + 1); // Must add 1! // Roll within this range internalSetTime(uprv_fmod((internalGetTime() + delta - min2), gap2)); if (internalGetTime() < 0) internalSetTime(internalGetTime() + gap2); setTimeInMillis(internalGetTime() + min2, status); return; } case UCAL_ZONE_OFFSET: case UCAL_DST_OFFSET: default: status = U_ILLEGAL_ARGUMENT_ERROR; return; // These fields cannot be rolled } // These are the standard roll instructions. These work for all // simple cases, that is, cases in which the limits are fixed, such // as the hour, the month, and the era. gap = max - min + 1; int32_t value = internalGet(field) + amount; value = (value - min) % gap; if (value < 0) value += gap; value += min; set(field, value); } // ------------------------------------- int32_t GregorianCalendar::getMinimum(EDateFields field) const { return getMinimum((UCalendarDateFields) field); } int32_t GregorianCalendar::getMinimum(UCalendarDateFields field) const { return kMinValues[field]; } // ------------------------------------- int32_t GregorianCalendar::getMaximum(EDateFields field) const { return getMaximum((UCalendarDateFields) field); } int32_t GregorianCalendar::getMaximum(UCalendarDateFields field) const { return kMaxValues[field]; } // ------------------------------------- int32_t GregorianCalendar::getGreatestMinimum(EDateFields field) const { return getGreatestMinimum((UCalendarDateFields) field); } int32_t GregorianCalendar::getGreatestMinimum(UCalendarDateFields field) const { return kMinValues[field]; } // ------------------------------------- int32_t GregorianCalendar::getLeastMaximum(EDateFields field) const { return getLeastMaximum((UCalendarDateFields) field); } int32_t GregorianCalendar::getLeastMaximum(UCalendarDateFields field) const { return kLeastMaxValues[field]; } // ------------------------------------- int32_t GregorianCalendar::getActualMinimum(EDateFields field) const { return getActualMinimum((UCalendarDateFields) field); } int32_t GregorianCalendar::getActualMinimum(UCalendarDateFields field) const { return getMinimum(field); } // ------------------------------------- int32_t GregorianCalendar::getActualMaximum(UCalendarDateFields field) const { /* It is a known limitation that the code here (and in getActualMinimum) * won't behave properly at the extreme limits of GregorianCalendar's * representable range (except for the code that handles the YEAR * field). That's because the ends of the representable range are at * odd spots in the year. For calendars with the default Gregorian * cutover, these limits are Sun Dec 02 16:47:04 GMT 292269055 BC to Sun * Aug 17 07:12:55 GMT 292278994 AD, somewhat different for non-GMT * zones. As a result, if the calendar is set to Aug 1 292278994 AD, * the actual maximum of DAY_OF_MONTH is 17, not 30. If the date is Mar * 31 in that year, the actual maximum month might be Jul, whereas is * the date is Mar 15, the actual maximum might be Aug -- depending on * the precise semantics that are desired. Similar considerations * affect all fields. Nonetheless, this effect is sufficiently arcane * that we permit it, rather than complicating the code to handle such * intricacies. - liu 8/20/98 */ UErrorCode status = U_ZERO_ERROR; switch (field) { // we have functions that enable us to fast-path number of days in month // of year case UCAL_DATE: return monthLength(get(UCAL_MONTH, status)); case UCAL_DAY_OF_YEAR: return yearLength(); // for week of year, week of month, or day of week in month, we // just fall back on the default implementation in Calendar (I'm not sure // we could do better by having special calculations here) case UCAL_WEEK_OF_YEAR: case UCAL_WEEK_OF_MONTH: case UCAL_DAY_OF_WEEK_IN_MONTH: return Calendar::getActualMaximum(field, status); case UCAL_YEAR: case UCAL_YEAR_WOY: /* The year computation is no different, in principle, from the * others, however, the range of possible maxima is large. In * addition, the way we know we've exceeded the range is different. * For these reasons, we use the special case code below to handle * this field. * * The actual maxima for YEAR depend on the type of calendar: * * Gregorian = May 17, 292275056 BC - Aug 17, 292278994 AD * Julian = Dec 2, 292269055 BC - Jan 3, 292272993 AD * Hybrid = Dec 2, 292269055 BC - Aug 17, 292278994 AD * * We know we've exceeded the maximum when either the month, date, * time, or era changes in response to setting the year. We don't * check for month, date, and time here because the year and era are * sufficient to detect an invalid year setting. NOTE: If code is * added to check the month and date in the future for some reason, * Feb 29 must be allowed to shift to Mar 1 when setting the year. */ { Calendar *cal = (Calendar*)this->clone(); cal->setLenient(TRUE); int32_t era = cal->get(UCAL_ERA, status); if(U_FAILURE(status)) return 0; UDate d = cal->getTime(status); if(U_FAILURE(status)) return 0; /* Perform a binary search, with the invariant that lowGood is a * valid year, and highBad is an out of range year. */ int32_t lowGood = getLeastMaximum(field); int32_t highBad = getMaximum(field) + 1; while((lowGood + 1) < highBad) { int32_t y = (lowGood + highBad) / 2; cal->set(field, y); if(cal->get(field, status) == y && cal->get(UCAL_ERA, status) == era) { lowGood = y; } else { highBad = y; cal->setTime(d, status); // Restore original fields } } delete cal; return lowGood; } // and we know none of the other fields have variable maxima in // GregorianCalendar, so we can just return the fixed maximum default: return getMaximum(field); } } // ------------------------------------- UBool GregorianCalendar::inDaylightTime(UErrorCode& status) const { if (U_FAILURE(status) || !getTimeZone().useDaylightTime()) return FALSE; // Force an update of the state of the Calendar. ((GregorianCalendar*)this)->complete(status); // cast away const return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE); } // ------------------------------------- /** * 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 GregorianCalendar::internalGetEra() const { return isSet(UCAL_ERA) ? internalGet(UCAL_ERA) : AD; } const char * GregorianCalendar::getType() const { //static const char kGregorianType = "gregorian"; return "gregorian"; } // ------ Default Century functions moved here from SimpleDateFormat // uncomment in 2.8 //const UDate GregorianCalendar::fgSystemDefaultCentury = DBL_MIN; const int32_t GregorianCalendar::fgSystemDefaultCenturyYear = -1; UDate GregorianCalendar::fgSystemDefaultCenturyStart = DBL_MIN; int32_t GregorianCalendar::fgSystemDefaultCenturyStartYear = -1; UBool GregorianCalendar::haveDefaultCentury() const { return TRUE; } UDate GregorianCalendar::defaultCenturyStart() const { return internalGetDefaultCenturyStart(); } int32_t GregorianCalendar::defaultCenturyStartYear() const { return internalGetDefaultCenturyStartYear(); } UDate GregorianCalendar::internalGetDefaultCenturyStart() const { // lazy-evaluate systemDefaultCenturyStart UBool needsUpdate; { Mutex m; needsUpdate = (fgSystemDefaultCenturyStart == SimpleDateFormat::fgSystemDefaultCentury); } if (needsUpdate) { initializeSystemDefaultCentury(); } // use defaultCenturyStart unless it's the flag value; // then use systemDefaultCenturyStart return fgSystemDefaultCenturyStart; } int32_t GregorianCalendar::internalGetDefaultCenturyStartYear() const { // lazy-evaluate systemDefaultCenturyStartYear UBool needsUpdate; { Mutex m; needsUpdate = (fgSystemDefaultCenturyStart == SimpleDateFormat::fgSystemDefaultCentury); } if (needsUpdate) { initializeSystemDefaultCentury(); } // use defaultCenturyStart unless it's the flag value; // then use systemDefaultCenturyStartYear return fgSystemDefaultCenturyStartYear; } void GregorianCalendar::initializeSystemDefaultCentury() { // initialize systemDefaultCentury and systemDefaultCenturyYear based // on the current time. They'll be set to 80 years before // the current time. // No point in locking as it should be idempotent. if (fgSystemDefaultCenturyStart == SimpleDateFormat::fgSystemDefaultCentury) { UErrorCode status = U_ZERO_ERROR; Calendar *calendar = new GregorianCalendar(status); if (calendar != NULL && U_SUCCESS(status)) { calendar->setTime(Calendar::getNow(), status); calendar->add(UCAL_YEAR, -80, status); UDate newStart = calendar->getTime(status); int32_t newYear = calendar->get(UCAL_YEAR, status); { Mutex m; fgSystemDefaultCenturyStart = newStart; fgSystemDefaultCenturyStartYear = newYear; } delete calendar; } // We have no recourse upon failure unless we want to propagate the failure // out. } } U_NAMESPACE_END #endif /* #if !UCONFIG_NO_FORMATTING */ //eof