/* * Copyright (C) 2003-2004, International Business Machines Corporation * and others. All Rights Reserved. ****************************************************************************** * * File HEBRWCAL.H * * Modification History: * * Date Name Description * 12/03/2003 srl ported from java HebrewCalendar ***************************************************************************** */ #include "hebrwcal.h" #if !UCONFIG_NO_FORMATTING #include "mutex.h" #include <float.h> #include "gregoimp.h" // Math #include "astro.h" // CalendarAstronomer #include "uhash.h" #include "ucln_in.h" // Hebrew Calendar implementation /** * The absolute date, in milliseconds since 1/1/1970 AD, Gregorian, * of the start of the Hebrew calendar. In order to keep this calendar's * time of day in sync with that of the Gregorian calendar, we use * midnight, rather than sunset the day before. */ static const double EPOCH_MILLIS = -180799862400000.; // 1/1/1 HY static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = { // Minimum Greatest Least Maximum // Minimum Maximum { 0, 0, 0, 0 }, // ERA { 1, 1, 5000000, 5000000 }, // YEAR { 0, 0, 12, 12 }, // MONTH { 1, 1, 51, 56 }, // WEEK_OF_YEAR { 0, 0, 5, 6 }, // WEEK_OF_MONTH { 1, 1, 29, 30 }, // DAY_OF_MONTH { 1, 1, 353, 385 }, // DAY_OF_YEAR {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK { -1, -1, 4, 6 }, // DAY_OF_WEEK_IN_MONTH {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1/* */}, // AM_PM {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET { -5000001, -5000001, 5000001, 5000001 }, // YEAR_WOY {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL { -5000000, -5000000, 5000000, 5000000 }, // EXTENDED_YEAR {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY }; /** * The lengths of the Hebrew months. This is complicated, because there * are three different types of years, or six if you count leap years. * Due to the rules for postponing the start of the year to avoid having * certain holidays fall on the sabbath, the year can end up being three * different lengths, called "deficient", "normal", and "complete". */ static const int32_t MONTH_LENGTH[][3] = { // Deficient Normal Complete { 30, 30, 30 }, //Tishri { 29, 29, 30 }, //Heshvan { 29, 30, 30 }, //Kislev { 29, 29, 29 }, //Tevet { 30, 30, 30 }, //Shevat { 30, 30, 30 }, //Adar I (leap years only) { 29, 29, 29 }, //Adar { 30, 30, 30 }, //Nisan { 29, 29, 29 }, //Iyar { 30, 30, 30 }, //Sivan { 29, 29, 29 }, //Tammuz { 30, 30, 30 }, //Av { 29, 29, 29 }, //Elul }; /** * The cumulative # of days to the end of each month in a non-leap year * Although this can be calculated from the MONTH_LENGTH table, * keeping it around separately makes some calculations a lot faster */ static const int32_t MONTH_START[][3] = { // Deficient Normal Complete { 0, 0, 0 }, // (placeholder) { 30, 30, 30 }, // Tishri { 59, 59, 60 }, // Heshvan { 88, 89, 90 }, // Kislev { 117, 118, 119 }, // Tevet { 147, 148, 149 }, // Shevat { 147, 148, 149 }, // (Adar I placeholder) { 176, 177, 178 }, // Adar { 206, 207, 208 }, // Nisan { 235, 236, 237 }, // Iyar { 265, 266, 267 }, // Sivan { 294, 295, 296 }, // Tammuz { 324, 325, 326 }, // Av { 353, 354, 355 }, // Elul }; /** * The cumulative # of days to the end of each month in a leap year */ static const int32_t LEAP_MONTH_START[][3] = { // Deficient Normal Complete { 0, 0, 0 }, // (placeholder) { 30, 30, 30 }, // Tishri { 59, 59, 60 }, // Heshvan { 88, 89, 90 }, // Kislev { 117, 118, 119 }, // Tevet { 147, 148, 149 }, // Shevat { 177, 178, 179 }, // Adar I { 206, 207, 208 }, // Adar II { 236, 237, 238 }, // Nisan { 265, 266, 267 }, // Iyar { 295, 296, 297 }, // Sivan { 324, 325, 326 }, // Tammuz { 354, 355, 356 }, // Av { 383, 384, 385 }, // Elul }; static CalendarCache *gCache = NULL; U_CDECL_BEGIN static UBool calendar_hebrew_cleanup(void) { delete gCache; gCache = NULL; return TRUE; } U_CDECL_END U_NAMESPACE_BEGIN //------------------------------------------------------------------------- // Constructors... //------------------------------------------------------------------------- /** * Constructs a default <code>HebrewCalendar</code> using the current time * in the default time zone with the default locale. * @internal */ HebrewCalendar::HebrewCalendar(const Locale& aLocale, UErrorCode& success) : Calendar(TimeZone::createDefault(), aLocale, success) { setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly. } HebrewCalendar::~HebrewCalendar() { } const char *HebrewCalendar::getType() const { return "hebrew"; } Calendar* HebrewCalendar::clone() const { return new HebrewCalendar(*this); } HebrewCalendar::HebrewCalendar(const HebrewCalendar& other) : Calendar(other) { } //------------------------------------------------------------------------- // Rolling and adding functions overridden from Calendar // // These methods call through to the default implementation in IBMCalendar // for most of the fields and only handle the unusual ones themselves. //------------------------------------------------------------------------- /** * Add a signed amount to a specified field, using this calendar's rules. * For example, to add three days to the current date, you can call * <code>add(Calendar.DATE, 3)</code>. * <p> * When adding to certain fields, the values of other fields may conflict and * need to be changed. For example, when adding one to the {@link #MONTH MONTH} field * for the date "30 Av 5758", the {@link #DAY_OF_MONTH DAY_OF_MONTH} field * must be adjusted so that the result is "29 Elul 5758" rather than the invalid * "30 Elul 5758". * <p> * This method is able to add to * all fields except for {@link #ERA ERA}, {@link #DST_OFFSET DST_OFFSET}, * and {@link #ZONE_OFFSET ZONE_OFFSET}. * <p> * <b>Note:</b> You should always use {@link #roll roll} and add rather * than attempting to perform arithmetic operations directly on the fields * of a <tt>HebrewCalendar</tt>. Since the {@link #MONTH MONTH} field behaves * discontinuously in non-leap years, simple arithmetic can give invalid results. * <p> * @param field the time field. * @param amount the amount to add to the field. * * @exception IllegalArgumentException if the field is invalid or refers * to a field that cannot be handled by this method. * @internal */ void HebrewCalendar::add(UCalendarDateFields field, int32_t amount, UErrorCode& status) { if(U_FAILURE(status)) { return; } switch (field) { case UCAL_MONTH: { // We can't just do a set(MONTH, get(MONTH) + amount). The // reason is ADAR_1. Suppose amount is +2 and we land in // ADAR_1 -- then we have to bump to ADAR_2 aka ADAR. But // if amount is -2 and we land in ADAR_1, then we have to // bump the other way -- down to SHEVAT. - Alan 11/00 int32_t month = get(UCAL_MONTH, status); int32_t year = get(UCAL_YEAR, status); UBool acrossAdar1; if (amount > 0) { acrossAdar1 = (month < ADAR_1); // started before ADAR_1? month += amount; for (;;) { if (acrossAdar1 && month>=ADAR_1 && !isLeapYear(year)) { ++month; } if (month <= ELUL) { break; } month -= ELUL+1; ++year; acrossAdar1 = TRUE; } } else { acrossAdar1 = (month > ADAR_1); // started after ADAR_1? month += amount; for (;;) { if (acrossAdar1 && month<=ADAR_1 && !isLeapYear(year)) { --month; } if (month >= 0) { break; } month += ELUL+1; --year; acrossAdar1 = TRUE; } } set(UCAL_MONTH, month); set(UCAL_YEAR, year); pinField(UCAL_DAY_OF_MONTH, status); break; } default: Calendar::add(field, amount, status); break; } } /** * Rolls (up/down) a specified amount time on the given field. For * example, to roll the current date up by three days, you can call * <code>roll(Calendar.DATE, 3)</code>. If the * field is rolled past its maximum allowable value, it will "wrap" back * to its minimum and continue rolling. * For example, calling <code>roll(Calendar.DATE, 10)</code> * on a Hebrew calendar set to "25 Av 5758" will result in the date "5 Av 5758". * <p> * When rolling certain fields, the values of other fields may conflict and * need to be changed. For example, when rolling the {@link #MONTH MONTH} field * upward by one for the date "30 Av 5758", the {@link #DAY_OF_MONTH DAY_OF_MONTH} field * must be adjusted so that the result is "29 Elul 5758" rather than the invalid * "30 Elul". * <p> * This method is able to roll * all fields except for {@link #ERA ERA}, {@link #DST_OFFSET DST_OFFSET}, * and {@link #ZONE_OFFSET ZONE_OFFSET}. Subclasses may, of course, add support for * additional fields in their overrides of <code>roll</code>. * <p> * <b>Note:</b> You should always use roll and {@link #add add} rather * than attempting to perform arithmetic operations directly on the fields * of a <tt>HebrewCalendar</tt>. Since the {@link #MONTH MONTH} field behaves * discontinuously in non-leap years, simple arithmetic can give invalid results. * <p> * @param field the time field. * @param amount the amount by which the field should be rolled. * * @exception IllegalArgumentException if the field is invalid or refers * to a field that cannot be handled by this method. * @internal */ void HebrewCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) { if(U_FAILURE(status)) { return; } switch (field) { case UCAL_MONTH: { int32_t month = get(UCAL_MONTH, status); int32_t year = get(UCAL_YEAR, status); UBool leapYear = isLeapYear(year); int32_t yearLength = monthsInYear(year); int32_t newMonth = month + (amount % yearLength); // // If it's not a leap year and we're rolling past the missing month // of ADAR_1, we need to roll an extra month to make up for it. // if (!leapYear) { if (amount > 0 && month < ADAR_1 && newMonth >= ADAR_1) { newMonth++; } else if (amount < 0 && month > ADAR_1 && newMonth <= ADAR_1) { newMonth--; } } set(UCAL_MONTH, (newMonth + 13) % 13); pinField(UCAL_DAY_OF_MONTH, status); return; } default: Calendar::roll(field, amount, status); } } void HebrewCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status) { roll((UCalendarDateFields)field, amount, status); } //------------------------------------------------------------------------- // Support methods //------------------------------------------------------------------------- // Hebrew date calculations are performed in terms of days, hours, and // "parts" (or halakim), which are 1/1080 of an hour, or 3 1/3 seconds. static const int32_t HOUR_PARTS = 1080; static const int32_t DAY_PARTS = 24*HOUR_PARTS; // An approximate value for the length of a lunar month. // It is used to calculate the approximate year and month of a given // absolute date. static const int32_t MONTH_DAYS = 29; static const int32_t MONTH_FRACT = 12*HOUR_PARTS + 793; static const int32_t MONTH_PARTS = MONTH_DAYS*DAY_PARTS + MONTH_FRACT; // The time of the new moon (in parts) on 1 Tishri, year 1 (the epoch) // counting from noon on the day before. BAHARAD is an abbreviation of // Bet (Monday), Hey (5 hours from sunset), Resh-Daled (204). static const int32_t BAHARAD = 11*HOUR_PARTS + 204; /** * Finds the day # of the first day in the given Hebrew year. * To do this, we want to calculate the time of the Tishri 1 new moon * in that year. * <p> * The algorithm here is similar to ones described in a number of * references, including: * <ul> * <li>"Calendrical Calculations", by Nachum Dershowitz & Edward Reingold, * Cambridge University Press, 1997, pages 85-91. * * <li>Hebrew Calendar Science and Myths, * <a href="http://www.geocities.com/Athens/1584/"> * http://www.geocities.com/Athens/1584/</a> * * <li>The Calendar FAQ, * <a href="http://www.faqs.org/faqs/calendars/faq/"> * http://www.faqs.org/faqs/calendars/faq/</a> * </ul> */ int32_t HebrewCalendar::startOfYear(int32_t year, UErrorCode &status) { ucln_i18n_registerCleanup(UCLN_I18N_HEBREW_CALENDAR, calendar_hebrew_cleanup); int32_t day = CalendarCache::get(&gCache, year, status); if (day == 0) { int32_t months = (235 * year - 234) / 19; // # of months before year int32_t frac = months * MONTH_FRACT + BAHARAD; // Fractional part of day # day = months * 29 + (frac / DAY_PARTS); // Whole # part of calculation frac = frac % DAY_PARTS; // Time of day int32_t wd = (day % 7); // Day of week (0 == Monday) if (wd == 2 || wd == 4 || wd == 6) { // If the 1st is on Sun, Wed, or Fri, postpone to the next day day += 1; wd = (day % 7); } if (wd == 1 && frac > 15*HOUR_PARTS+204 && !isLeapYear(year) ) { // If the new moon falls after 3:11:20am (15h204p from the previous noon) // on a Tuesday and it is not a leap year, postpone by 2 days. // This prevents 356-day years. day += 2; } else if (wd == 0 && frac > 21*HOUR_PARTS+589 && isLeapYear(year-1) ) { // If the new moon falls after 9:32:43 1/3am (21h589p from yesterday noon) // on a Monday and *last* year was a leap year, postpone by 1 day. // Prevents 382-day years. day += 1; } CalendarCache::put(&gCache, year, day, status); } return day; } /** * Find the day of the week for a given day * * @param day The # of days since the start of the Hebrew calendar, * 1-based (i.e. 1/1/1 AM is day 1). */ int32_t HebrewCalendar::absoluteDayToDayOfWeek(int32_t day) { // We know that 1/1/1 AM is a Monday, which makes the math easy... return (day % 7) + 1; } /** * Returns the the type of a given year. * 0 "Deficient" year with 353 or 383 days * 1 "Normal" year with 354 or 384 days * 2 "Complete" year with 355 or 385 days */ int32_t HebrewCalendar::yearType(int32_t year) const { int32_t yearLength = handleGetYearLength(year); if (yearLength > 380) { yearLength -= 30; // Subtract length of leap month. } int type = 0; switch (yearLength) { case 353: type = 0; break; case 354: type = 1; break; case 355: type = 2; break; default: //throw new RuntimeException("Illegal year length " + yearLength + " in year " + year); type = 1; } return type; } /** * Determine whether a given Hebrew year is a leap year * * The rule here is that if (year % 19) == 0, 3, 6, 8, 11, 14, or 17. * The formula below performs the same test, believe it or not. */ UBool HebrewCalendar::isLeapYear(int32_t year) { //return (year * 12 + 17) % 19 >= 12; int32_t x = (year*12 + 17) % 19; return x >= ((x < 0) ? -7 : 12); } int32_t HebrewCalendar::monthsInYear(int32_t year) { return isLeapYear(year) ? 13 : 12; } //------------------------------------------------------------------------- // Calendar framework //------------------------------------------------------------------------- /** * @internal */ int32_t HebrewCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const { return LIMITS[field][limitType]; } /** * Returns the length of the given month in the given year * @internal */ int32_t HebrewCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const { switch (month) { case HESHVAN: case KISLEV: // These two month lengths can vary return MONTH_LENGTH[month][yearType(extendedYear)]; default: // The rest are a fixed length return MONTH_LENGTH[month][0]; } } /** * Returns the number of days in the given Hebrew year * @internal */ int32_t HebrewCalendar::handleGetYearLength(int32_t eyear) const { UErrorCode status = U_ZERO_ERROR; return startOfYear(eyear+1, status) - startOfYear(eyear, status); } //------------------------------------------------------------------------- // Functions for converting from milliseconds to field values //------------------------------------------------------------------------- /** * Subclasses may override this method to compute several fields * specific to each calendar system. These are: * * <ul><li>ERA * <li>YEAR * <li>MONTH * <li>DAY_OF_MONTH * <li>DAY_OF_YEAR * <li>EXTENDED_YEAR</ul> * * Subclasses can refer to the DAY_OF_WEEK and DOW_LOCAL fields, * which will be set when this method is called. Subclasses can * also call the getGregorianXxx() methods to obtain Gregorian * calendar equivalents for the given Julian day. * * <p>In addition, subclasses should compute any subclass-specific * fields, that is, fields from BASE_FIELD_COUNT to * getFieldCount() - 1. * @internal */ void HebrewCalendar::handleComputeFields(int32_t julianDay, UErrorCode &status) { int32_t d = julianDay - 347997; double m = ((d * (double)DAY_PARTS)/ (double) MONTH_PARTS); // Months (approx) int32_t year = (int32_t)( ((19. * m + 234.) / 235.) + 1.); // Years (approx) int32_t ys = startOfYear(year, status); // 1st day of year int32_t dayOfYear = (d - ys); // Because of the postponement rules, it's possible to guess wrong. Fix it. while (dayOfYear < 1) { year--; ys = startOfYear(year, status); dayOfYear = (d - ys); } // Now figure out which month we're in, and the date within that month int32_t type = yearType(year); UBool isLeap = isLeapYear(year); int32_t month = 0; while (dayOfYear > ( isLeap ? LEAP_MONTH_START[month][type] : MONTH_START[month][type] ) ) { month++; } month--; int dayOfMonth = dayOfYear - (isLeap ? LEAP_MONTH_START[month][type] : MONTH_START[month][type]); internalSet(UCAL_ERA, 0); internalSet(UCAL_YEAR, year); internalSet(UCAL_EXTENDED_YEAR, year); internalSet(UCAL_MONTH, month); internalSet(UCAL_DAY_OF_MONTH, dayOfMonth); internalSet(UCAL_DAY_OF_YEAR, dayOfYear); } //------------------------------------------------------------------------- // Functions for converting from field values to milliseconds //------------------------------------------------------------------------- /** * @internal */ int32_t HebrewCalendar::handleGetExtendedYear() { int32_t year; if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) { year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1 } else { year = internalGet(UCAL_YEAR, 1); // Default to year 1 } return year; } /** * Return JD of start of given month/year. * @internal */ int32_t HebrewCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool /*useMonth*/) const { UErrorCode status = U_ZERO_ERROR; // Resolve out-of-range months. This is necessary in order to // obtain the correct year. We correct to // a 12- or 13-month year (add/subtract 12 or 13, depending // on the year) but since we _always_ number from 0..12, and // the leap year determines whether or not month 5 (Adar 1) // is present, we allow 0..12 in any given year. while (month < 0) { month += monthsInYear(--eyear); } // Careful: allow 0..12 in all years while (month > 12) { month -= monthsInYear(eyear++); } int32_t day = startOfYear(eyear, status); if(U_FAILURE(status)) { return 0; } if (month != 0) { if (isLeapYear(eyear)) { day += LEAP_MONTH_START[month][yearType(eyear)]; } else { day += MONTH_START[month][yearType(eyear)]; } } return (int) (day + 347997); } UBool HebrewCalendar::inDaylightTime(UErrorCode& status) const { // copied from GregorianCalendar if (U_FAILURE(status) || !getTimeZone().useDaylightTime()) return FALSE; // Force an update of the state of the Calendar. ((HebrewCalendar*)this)->complete(status); // cast away const return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE); } // default century const UDate HebrewCalendar::fgSystemDefaultCentury = DBL_MIN; const int32_t HebrewCalendar::fgSystemDefaultCenturyYear = -1; UDate HebrewCalendar::fgSystemDefaultCenturyStart = DBL_MIN; int32_t HebrewCalendar::fgSystemDefaultCenturyStartYear = -1; UBool HebrewCalendar::haveDefaultCentury() const { return TRUE; } UDate HebrewCalendar::defaultCenturyStart() const { return internalGetDefaultCenturyStart(); } int32_t HebrewCalendar::defaultCenturyStartYear() const { return internalGetDefaultCenturyStartYear(); } UDate HebrewCalendar::internalGetDefaultCenturyStart() const { // lazy-evaluate systemDefaultCenturyStart UBool needsUpdate; { Mutex m; needsUpdate = (fgSystemDefaultCenturyStart == fgSystemDefaultCentury); } if (needsUpdate) { initializeSystemDefaultCentury(); } // use defaultCenturyStart unless it's the flag value; // then use systemDefaultCenturyStart return fgSystemDefaultCenturyStart; } int32_t HebrewCalendar::internalGetDefaultCenturyStartYear() const { // lazy-evaluate systemDefaultCenturyStartYear UBool needsUpdate; { Mutex m; needsUpdate = (fgSystemDefaultCenturyStart == fgSystemDefaultCentury); } if (needsUpdate) { initializeSystemDefaultCentury(); } // use defaultCenturyStart unless it's the flag value; // then use systemDefaultCenturyStartYear return fgSystemDefaultCenturyStartYear; } void HebrewCalendar::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 == fgSystemDefaultCentury) { UErrorCode status = U_ZERO_ERROR; HebrewCalendar calendar(Locale("@calendar=hebrew"),status); if (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; } } // We have no recourse upon failure unless we want to propagate the failure // out. } } UOBJECT_DEFINE_RTTI_IMPLEMENTATION(HebrewCalendar); U_NAMESPACE_END #endif // UCONFIG_NO_FORMATTING