| /* |
| ****************************************************************************** |
| * Copyright (C) 2007-2014, International Business Machines Corporation |
| * and others. All Rights Reserved. |
| ****************************************************************************** |
| * |
| * File CHNSECAL.CPP |
| * |
| * Modification History: |
| * |
| * Date Name Description |
| * 9/18/2007 ajmacher ported from java ChineseCalendar |
| ***************************************************************************** |
| */ |
| |
| #include "chnsecal.h" |
| |
| #if !UCONFIG_NO_FORMATTING |
| |
| #include "starboard/client_porting/poem/string_poem.h" |
| #include "umutex.h" |
| #include <float.h> |
| #include "gregoimp.h" // Math |
| #include "astro.h" // CalendarAstronomer |
| #include "unicode/simpletz.h" |
| #include "uhash.h" |
| #include "ucln_in.h" |
| |
| // Debugging |
| #ifdef U_DEBUG_CHNSECAL |
| # include <stdio.h> |
| # include <stdarg.h> |
| static void debug_chnsecal_loc(const char *f, int32_t l) |
| { |
| fprintf(stderr, "%s:%d: ", f, l); |
| } |
| |
| static void debug_chnsecal_msg(const char *pat, ...) |
| { |
| va_list ap; |
| va_start(ap, pat); |
| vfprintf(stderr, pat, ap); |
| fflush(stderr); |
| } |
| // must use double parens, i.e.: U_DEBUG_CHNSECAL_MSG(("four is: %d",4)); |
| #define U_DEBUG_CHNSECAL_MSG(x) {debug_chnsecal_loc(__FILE__,__LINE__);debug_chnsecal_msg x;} |
| #else |
| #define U_DEBUG_CHNSECAL_MSG(x) |
| #endif |
| |
| |
| // --- The cache -- |
| static UMutex astroLock = U_MUTEX_INITIALIZER; // Protects access to gChineseCalendarAstro. |
| static icu::CalendarAstronomer *gChineseCalendarAstro = NULL; |
| |
| // Lazy Creation & Access synchronized by class CalendarCache with a mutex. |
| static icu::CalendarCache *gChineseCalendarWinterSolsticeCache = NULL; |
| static icu::CalendarCache *gChineseCalendarNewYearCache = NULL; |
| |
| static icu::TimeZone *gChineseCalendarZoneAstroCalc = NULL; |
| static icu::UInitOnce gChineseCalendarZoneAstroCalcInitOnce = U_INITONCE_INITIALIZER; |
| |
| /** |
| * The start year of the Chinese calendar, the 61st year of the reign |
| * of Huang Di. Some sources use the first year of his reign, |
| * resulting in EXTENDED_YEAR values 60 years greater and ERA (cycle) |
| * values one greater. |
| */ |
| static const int32_t CHINESE_EPOCH_YEAR = -2636; // Gregorian year |
| |
| /** |
| * The offset from GMT in milliseconds at which we perform astronomical |
| * computations. Some sources use a different historically accurate |
| * offset of GMT+7:45:40 for years before 1929; we do not do this. |
| */ |
| static const int32_t CHINA_OFFSET = 8 * kOneHour; |
| |
| /** |
| * Value to be added or subtracted from the local days of a new moon to |
| * get close to the next or prior new moon, but not cross it. Must be |
| * >= 1 and < CalendarAstronomer.SYNODIC_MONTH. |
| */ |
| static const int32_t SYNODIC_GAP = 25; |
| |
| |
| U_CDECL_BEGIN |
| static UBool calendar_chinese_cleanup(void) { |
| if (gChineseCalendarAstro) { |
| delete gChineseCalendarAstro; |
| gChineseCalendarAstro = NULL; |
| } |
| if (gChineseCalendarWinterSolsticeCache) { |
| delete gChineseCalendarWinterSolsticeCache; |
| gChineseCalendarWinterSolsticeCache = NULL; |
| } |
| if (gChineseCalendarNewYearCache) { |
| delete gChineseCalendarNewYearCache; |
| gChineseCalendarNewYearCache = NULL; |
| } |
| if (gChineseCalendarZoneAstroCalc) { |
| delete gChineseCalendarZoneAstroCalc; |
| gChineseCalendarZoneAstroCalc = NULL; |
| } |
| gChineseCalendarZoneAstroCalcInitOnce.reset(); |
| return TRUE; |
| } |
| U_CDECL_END |
| |
| U_NAMESPACE_BEGIN |
| |
| |
| // Implementation of the ChineseCalendar class |
| |
| |
| //------------------------------------------------------------------------- |
| // Constructors... |
| //------------------------------------------------------------------------- |
| |
| |
| Calendar* ChineseCalendar::clone() const { |
| return new ChineseCalendar(*this); |
| } |
| |
| ChineseCalendar::ChineseCalendar(const Locale& aLocale, UErrorCode& success) |
| : Calendar(TimeZone::createDefault(), aLocale, success), |
| isLeapYear(FALSE), |
| fEpochYear(CHINESE_EPOCH_YEAR), |
| fZoneAstroCalc(getChineseCalZoneAstroCalc()) |
| { |
| setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly. |
| } |
| |
| ChineseCalendar::ChineseCalendar(const Locale& aLocale, int32_t epochYear, |
| const TimeZone* zoneAstroCalc, UErrorCode &success) |
| : Calendar(TimeZone::createDefault(), aLocale, success), |
| isLeapYear(FALSE), |
| fEpochYear(epochYear), |
| fZoneAstroCalc(zoneAstroCalc) |
| { |
| setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly. |
| } |
| |
| ChineseCalendar::ChineseCalendar(const ChineseCalendar& other) : Calendar(other) { |
| isLeapYear = other.isLeapYear; |
| fEpochYear = other.fEpochYear; |
| fZoneAstroCalc = other.fZoneAstroCalc; |
| } |
| |
| ChineseCalendar::~ChineseCalendar() |
| { |
| } |
| |
| const char *ChineseCalendar::getType() const { |
| return "chinese"; |
| } |
| |
| static void U_CALLCONV initChineseCalZoneAstroCalc() { |
| gChineseCalendarZoneAstroCalc = new SimpleTimeZone(CHINA_OFFSET, UNICODE_STRING_SIMPLE("CHINA_ZONE") ); |
| ucln_i18n_registerCleanup(UCLN_I18N_CHINESE_CALENDAR, calendar_chinese_cleanup); |
| } |
| |
| const TimeZone* ChineseCalendar::getChineseCalZoneAstroCalc(void) const { |
| umtx_initOnce(gChineseCalendarZoneAstroCalcInitOnce, &initChineseCalZoneAstroCalc); |
| return gChineseCalendarZoneAstroCalc; |
| } |
| |
| //------------------------------------------------------------------------- |
| // Minimum / Maximum access functions |
| //------------------------------------------------------------------------- |
| |
| |
| static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = { |
| // Minimum Greatest Least Maximum |
| // Minimum Maximum |
| { 1, 1, 83333, 83333}, // ERA |
| { 1, 1, 60, 60}, // YEAR |
| { 0, 0, 11, 11}, // MONTH |
| { 1, 1, 50, 55}, // WEEK_OF_YEAR |
| {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // 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, 5, 5}, // 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 |
| { -5000000, -5000000, 5000000, 5000000}, // 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 |
| { 0, 0, 1, 1}, // IS_LEAP_MONTH |
| }; |
| |
| |
| /** |
| * @draft ICU 2.4 |
| */ |
| int32_t ChineseCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const { |
| return LIMITS[field][limitType]; |
| } |
| |
| |
| //---------------------------------------------------------------------- |
| // Calendar framework |
| //---------------------------------------------------------------------- |
| |
| /** |
| * Implement abstract Calendar method to return the extended year |
| * defined by the current fields. This will use either the ERA and |
| * YEAR field as the cycle and year-of-cycle, or the EXTENDED_YEAR |
| * field as the continuous year count, depending on which is newer. |
| * @stable ICU 2.8 |
| */ |
| int32_t ChineseCalendar::handleGetExtendedYear() { |
| int32_t year; |
| if (newestStamp(UCAL_ERA, UCAL_YEAR, kUnset) <= fStamp[UCAL_EXTENDED_YEAR]) { |
| year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1 |
| } else { |
| int32_t cycle = internalGet(UCAL_ERA, 1) - 1; // 0-based cycle |
| // adjust to the instance specific epoch |
| year = cycle * 60 + internalGet(UCAL_YEAR, 1) - (fEpochYear - CHINESE_EPOCH_YEAR); |
| } |
| return year; |
| } |
| |
| /** |
| * Override Calendar method to return the number of days in the given |
| * extended year and month. |
| * |
| * <p>Note: This method also reads the IS_LEAP_MONTH field to determine |
| * whether or not the given month is a leap month. |
| * @stable ICU 2.8 |
| */ |
| int32_t ChineseCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const { |
| int32_t thisStart = handleComputeMonthStart(extendedYear, month, TRUE) - |
| kEpochStartAsJulianDay + 1; // Julian day -> local days |
| int32_t nextStart = newMoonNear(thisStart + SYNODIC_GAP, TRUE); |
| return nextStart - thisStart; |
| } |
| |
| /** |
| * Override Calendar to compute several fields specific to the Chinese |
| * calendar system. These are: |
| * |
| * <ul><li>ERA |
| * <li>YEAR |
| * <li>MONTH |
| * <li>DAY_OF_MONTH |
| * <li>DAY_OF_YEAR |
| * <li>EXTENDED_YEAR</ul> |
| * |
| * The DAY_OF_WEEK and DOW_LOCAL fields are already set when this |
| * method is called. The getGregorianXxx() methods return Gregorian |
| * calendar equivalents for the given Julian day. |
| * |
| * <p>Compute the ChineseCalendar-specific field IS_LEAP_MONTH. |
| * @stable ICU 2.8 |
| */ |
| void ChineseCalendar::handleComputeFields(int32_t julianDay, UErrorCode &/*status*/) { |
| |
| computeChineseFields(julianDay - kEpochStartAsJulianDay, // local days |
| getGregorianYear(), getGregorianMonth(), |
| TRUE); // set all fields |
| } |
| |
| /** |
| * Field resolution table that incorporates IS_LEAP_MONTH. |
| */ |
| const UFieldResolutionTable ChineseCalendar::CHINESE_DATE_PRECEDENCE[] = |
| { |
| { |
| { UCAL_DAY_OF_MONTH, kResolveSTOP }, |
| { UCAL_WEEK_OF_YEAR, UCAL_DAY_OF_WEEK, kResolveSTOP }, |
| { UCAL_WEEK_OF_MONTH, UCAL_DAY_OF_WEEK, kResolveSTOP }, |
| { UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DAY_OF_WEEK, kResolveSTOP }, |
| { UCAL_WEEK_OF_YEAR, UCAL_DOW_LOCAL, kResolveSTOP }, |
| { UCAL_WEEK_OF_MONTH, UCAL_DOW_LOCAL, kResolveSTOP }, |
| { UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DOW_LOCAL, kResolveSTOP }, |
| { UCAL_DAY_OF_YEAR, kResolveSTOP }, |
| { kResolveRemap | UCAL_DAY_OF_MONTH, UCAL_IS_LEAP_MONTH, kResolveSTOP }, |
| { kResolveSTOP } |
| }, |
| { |
| { UCAL_WEEK_OF_YEAR, kResolveSTOP }, |
| { UCAL_WEEK_OF_MONTH, kResolveSTOP }, |
| { UCAL_DAY_OF_WEEK_IN_MONTH, kResolveSTOP }, |
| { kResolveRemap | UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DAY_OF_WEEK, kResolveSTOP }, |
| { kResolveRemap | UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DOW_LOCAL, kResolveSTOP }, |
| { kResolveSTOP } |
| }, |
| {{kResolveSTOP}} |
| }; |
| |
| /** |
| * Override Calendar to add IS_LEAP_MONTH to the field resolution |
| * table. |
| * @stable ICU 2.8 |
| */ |
| const UFieldResolutionTable* ChineseCalendar::getFieldResolutionTable() const { |
| return CHINESE_DATE_PRECEDENCE; |
| } |
| |
| /** |
| * Return the Julian day number of day before the first day of the |
| * given month in the given extended year. |
| * |
| * <p>Note: This method reads the IS_LEAP_MONTH field to determine |
| * whether the given month is a leap month. |
| * @param eyear the extended year |
| * @param month the zero-based month. The month is also determined |
| * by reading the IS_LEAP_MONTH field. |
| * @return the Julian day number of the day before the first |
| * day of the given month and year |
| * @stable ICU 2.8 |
| */ |
| int32_t ChineseCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool useMonth) const { |
| |
| ChineseCalendar *nonConstThis = (ChineseCalendar*)this; // cast away const |
| |
| // If the month is out of range, adjust it into range, and |
| // modify the extended year value accordingly. |
| if (month < 0 || month > 11) { |
| double m = month; |
| eyear += (int32_t)ClockMath::floorDivide(m, 12.0, m); |
| month = (int32_t)m; |
| } |
| |
| int32_t gyear = eyear + fEpochYear - 1; // Gregorian year |
| int32_t theNewYear = newYear(gyear); |
| int32_t newMoon = newMoonNear(theNewYear + month * 29, TRUE); |
| |
| int32_t julianDay = newMoon + kEpochStartAsJulianDay; |
| |
| // Save fields for later restoration |
| int32_t saveMonth = internalGet(UCAL_MONTH); |
| int32_t saveIsLeapMonth = internalGet(UCAL_IS_LEAP_MONTH); |
| |
| // Ignore IS_LEAP_MONTH field if useMonth is false |
| int32_t isLeapMonth = useMonth ? saveIsLeapMonth : 0; |
| |
| UErrorCode status = U_ZERO_ERROR; |
| nonConstThis->computeGregorianFields(julianDay, status); |
| if (U_FAILURE(status)) |
| return 0; |
| |
| // This will modify the MONTH and IS_LEAP_MONTH fields (only) |
| nonConstThis->computeChineseFields(newMoon, getGregorianYear(), |
| getGregorianMonth(), FALSE); |
| |
| if (month != internalGet(UCAL_MONTH) || |
| isLeapMonth != internalGet(UCAL_IS_LEAP_MONTH)) { |
| newMoon = newMoonNear(newMoon + SYNODIC_GAP, TRUE); |
| julianDay = newMoon + kEpochStartAsJulianDay; |
| } |
| |
| nonConstThis->internalSet(UCAL_MONTH, saveMonth); |
| nonConstThis->internalSet(UCAL_IS_LEAP_MONTH, saveIsLeapMonth); |
| |
| return julianDay - 1; |
| } |
| |
| |
| /** |
| * Override Calendar to handle leap months properly. |
| * @stable ICU 2.8 |
| */ |
| void ChineseCalendar::add(UCalendarDateFields field, int32_t amount, UErrorCode& status) { |
| switch (field) { |
| case UCAL_MONTH: |
| if (amount != 0) { |
| int32_t dom = get(UCAL_DAY_OF_MONTH, status); |
| if (U_FAILURE(status)) break; |
| int32_t day = get(UCAL_JULIAN_DAY, status) - kEpochStartAsJulianDay; // Get local day |
| if (U_FAILURE(status)) break; |
| int32_t moon = day - dom + 1; // New moon |
| offsetMonth(moon, dom, amount); |
| } |
| break; |
| default: |
| Calendar::add(field, amount, status); |
| break; |
| } |
| } |
| |
| /** |
| * Override Calendar to handle leap months properly. |
| * @stable ICU 2.8 |
| */ |
| void ChineseCalendar::add(EDateFields field, int32_t amount, UErrorCode& status) { |
| add((UCalendarDateFields)field, amount, status); |
| } |
| |
| /** |
| * Override Calendar to handle leap months properly. |
| * @stable ICU 2.8 |
| */ |
| void ChineseCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) { |
| switch (field) { |
| case UCAL_MONTH: |
| if (amount != 0) { |
| int32_t dom = get(UCAL_DAY_OF_MONTH, status); |
| if (U_FAILURE(status)) break; |
| int32_t day = get(UCAL_JULIAN_DAY, status) - kEpochStartAsJulianDay; // Get local day |
| if (U_FAILURE(status)) break; |
| int32_t moon = day - dom + 1; // New moon (start of this month) |
| |
| // Note throughout the following: Months 12 and 1 are never |
| // followed by a leap month (D&R p. 185). |
| |
| // Compute the adjusted month number m. This is zero-based |
| // value from 0..11 in a non-leap year, and from 0..12 in a |
| // leap year. |
| int32_t m = get(UCAL_MONTH, status); // 0-based month |
| if (U_FAILURE(status)) break; |
| if (isLeapYear) { // (member variable) |
| if (get(UCAL_IS_LEAP_MONTH, status) == 1) { |
| ++m; |
| } else { |
| // Check for a prior leap month. (In the |
| // following, month 0 is the first month of the |
| // year.) Month 0 is never followed by a leap |
| // month, and we know month m is not a leap month. |
| // moon1 will be the start of month 0 if there is |
| // no leap month between month 0 and month m; |
| // otherwise it will be the start of month 1. |
| int moon1 = moon - |
| (int) (CalendarAstronomer::SYNODIC_MONTH * (m - 0.5)); |
| moon1 = newMoonNear(moon1, TRUE); |
| if (isLeapMonthBetween(moon1, moon)) { |
| ++m; |
| } |
| } |
| if (U_FAILURE(status)) break; |
| } |
| |
| // Now do the standard roll computation on m, with the |
| // allowed range of 0..n-1, where n is 12 or 13. |
| int32_t n = isLeapYear ? 13 : 12; // Months in this year |
| int32_t newM = (m + amount) % n; |
| if (newM < 0) { |
| newM += n; |
| } |
| |
| if (newM != m) { |
| offsetMonth(moon, dom, newM - m); |
| } |
| } |
| break; |
| default: |
| Calendar::roll(field, amount, status); |
| break; |
| } |
| } |
| |
| void ChineseCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status) { |
| roll((UCalendarDateFields)field, amount, status); |
| } |
| |
| |
| //------------------------------------------------------------------ |
| // Support methods and constants |
| //------------------------------------------------------------------ |
| |
| /** |
| * Convert local days to UTC epoch milliseconds. |
| * This is not an accurate conversion in that getTimezoneOffset |
| * takes the milliseconds in GMT (not local time). In theory, more |
| * accurate algorithm can be implemented but practically we do not need |
| * to go through that complication as long as the historical timezone |
| * changes did not happen around the 'tricky' new moon (new moon around |
| * midnight). |
| * |
| * @param days days after January 1, 1970 0:00 in the astronomical base zone |
| * @return milliseconds after January 1, 1970 0:00 GMT |
| */ |
| double ChineseCalendar::daysToMillis(double days) const { |
| double millis = days * (double)kOneDay; |
| if (fZoneAstroCalc != NULL) { |
| int32_t rawOffset, dstOffset; |
| UErrorCode status = U_ZERO_ERROR; |
| fZoneAstroCalc->getOffset(millis, FALSE, rawOffset, dstOffset, status); |
| if (U_SUCCESS(status)) { |
| return millis - (double)(rawOffset + dstOffset); |
| } |
| } |
| return millis - (double)CHINA_OFFSET; |
| } |
| |
| /** |
| * Convert UTC epoch milliseconds to local days. |
| * @param millis milliseconds after January 1, 1970 0:00 GMT |
| * @return days after January 1, 1970 0:00 in the astronomical base zone |
| */ |
| double ChineseCalendar::millisToDays(double millis) const { |
| if (fZoneAstroCalc != NULL) { |
| int32_t rawOffset, dstOffset; |
| UErrorCode status = U_ZERO_ERROR; |
| fZoneAstroCalc->getOffset(millis, FALSE, rawOffset, dstOffset, status); |
| if (U_SUCCESS(status)) { |
| return ClockMath::floorDivide(millis + (double)(rawOffset + dstOffset), kOneDay); |
| } |
| } |
| return ClockMath::floorDivide(millis + (double)CHINA_OFFSET, kOneDay); |
| } |
| |
| //------------------------------------------------------------------ |
| // Astronomical computations |
| //------------------------------------------------------------------ |
| |
| |
| /** |
| * Return the major solar term on or after December 15 of the given |
| * Gregorian year, that is, the winter solstice of the given year. |
| * Computations are relative to Asia/Shanghai time zone. |
| * @param gyear a Gregorian year |
| * @return days after January 1, 1970 0:00 Asia/Shanghai of the |
| * winter solstice of the given year |
| */ |
| int32_t ChineseCalendar::winterSolstice(int32_t gyear) const { |
| |
| UErrorCode status = U_ZERO_ERROR; |
| int32_t cacheValue = CalendarCache::get(&gChineseCalendarWinterSolsticeCache, gyear, status); |
| |
| if (cacheValue == 0) { |
| // In books December 15 is used, but it fails for some years |
| // using our algorithms, e.g.: 1298 1391 1492 1553 1560. That |
| // is, winterSolstice(1298) starts search at Dec 14 08:00:00 |
| // PST 1298 with a final result of Dec 14 10:31:59 PST 1299. |
| double ms = daysToMillis(Grego::fieldsToDay(gyear, UCAL_DECEMBER, 1)); |
| |
| umtx_lock(&astroLock); |
| if(gChineseCalendarAstro == NULL) { |
| gChineseCalendarAstro = new CalendarAstronomer(); |
| ucln_i18n_registerCleanup(UCLN_I18N_CHINESE_CALENDAR, calendar_chinese_cleanup); |
| } |
| gChineseCalendarAstro->setTime(ms); |
| UDate solarLong = gChineseCalendarAstro->getSunTime(CalendarAstronomer::WINTER_SOLSTICE(), TRUE); |
| umtx_unlock(&astroLock); |
| |
| // Winter solstice is 270 degrees solar longitude aka Dongzhi |
| cacheValue = (int32_t)millisToDays(solarLong); |
| CalendarCache::put(&gChineseCalendarWinterSolsticeCache, gyear, cacheValue, status); |
| } |
| if(U_FAILURE(status)) { |
| cacheValue = 0; |
| } |
| return cacheValue; |
| } |
| |
| /** |
| * Return the closest new moon to the given date, searching either |
| * forward or backward in time. |
| * @param days days after January 1, 1970 0:00 Asia/Shanghai |
| * @param after if true, search for a new moon on or after the given |
| * date; otherwise, search for a new moon before it |
| * @return days after January 1, 1970 0:00 Asia/Shanghai of the nearest |
| * new moon after or before <code>days</code> |
| */ |
| int32_t ChineseCalendar::newMoonNear(double days, UBool after) const { |
| |
| umtx_lock(&astroLock); |
| if(gChineseCalendarAstro == NULL) { |
| gChineseCalendarAstro = new CalendarAstronomer(); |
| ucln_i18n_registerCleanup(UCLN_I18N_CHINESE_CALENDAR, calendar_chinese_cleanup); |
| } |
| gChineseCalendarAstro->setTime(daysToMillis(days)); |
| UDate newMoon = gChineseCalendarAstro->getMoonTime(CalendarAstronomer::NEW_MOON(), after); |
| umtx_unlock(&astroLock); |
| |
| return (int32_t) millisToDays(newMoon); |
| } |
| |
| /** |
| * Return the nearest integer number of synodic months between |
| * two dates. |
| * @param day1 days after January 1, 1970 0:00 Asia/Shanghai |
| * @param day2 days after January 1, 1970 0:00 Asia/Shanghai |
| * @return the nearest integer number of months between day1 and day2 |
| */ |
| int32_t ChineseCalendar::synodicMonthsBetween(int32_t day1, int32_t day2) const { |
| double roundme = ((day2 - day1) / CalendarAstronomer::SYNODIC_MONTH); |
| return (int32_t) (roundme + (roundme >= 0 ? .5 : -.5)); |
| } |
| |
| /** |
| * Return the major solar term on or before a given date. This |
| * will be an integer from 1..12, with 1 corresponding to 330 degrees, |
| * 2 to 0 degrees, 3 to 30 degrees,..., and 12 to 300 degrees. |
| * @param days days after January 1, 1970 0:00 Asia/Shanghai |
| */ |
| int32_t ChineseCalendar::majorSolarTerm(int32_t days) const { |
| |
| umtx_lock(&astroLock); |
| if(gChineseCalendarAstro == NULL) { |
| gChineseCalendarAstro = new CalendarAstronomer(); |
| ucln_i18n_registerCleanup(UCLN_I18N_CHINESE_CALENDAR, calendar_chinese_cleanup); |
| } |
| gChineseCalendarAstro->setTime(daysToMillis(days)); |
| UDate solarLongitude = gChineseCalendarAstro->getSunLongitude(); |
| umtx_unlock(&astroLock); |
| |
| // Compute (floor(solarLongitude / (pi/6)) + 2) % 12 |
| int32_t term = ( ((int32_t)(6 * solarLongitude / CalendarAstronomer::PI)) + 2 ) % 12; |
| if (term < 1) { |
| term += 12; |
| } |
| return term; |
| } |
| |
| /** |
| * Return true if the given month lacks a major solar term. |
| * @param newMoon days after January 1, 1970 0:00 Asia/Shanghai of a new |
| * moon |
| */ |
| UBool ChineseCalendar::hasNoMajorSolarTerm(int32_t newMoon) const { |
| return majorSolarTerm(newMoon) == |
| majorSolarTerm(newMoonNear(newMoon + SYNODIC_GAP, TRUE)); |
| } |
| |
| |
| //------------------------------------------------------------------ |
| // Time to fields |
| //------------------------------------------------------------------ |
| |
| /** |
| * Return true if there is a leap month on or after month newMoon1 and |
| * at or before month newMoon2. |
| * @param newMoon1 days after January 1, 1970 0:00 astronomical base zone |
| * of a new moon |
| * @param newMoon2 days after January 1, 1970 0:00 astronomical base zone |
| * of a new moon |
| */ |
| UBool ChineseCalendar::isLeapMonthBetween(int32_t newMoon1, int32_t newMoon2) const { |
| |
| #ifdef U_DEBUG_CHNSECAL |
| // This is only needed to debug the timeOfAngle divergence bug. |
| // Remove this later. Liu 11/9/00 |
| if (synodicMonthsBetween(newMoon1, newMoon2) >= 50) { |
| U_DEBUG_CHNSECAL_MSG(( |
| "isLeapMonthBetween(%d, %d): Invalid parameters", newMoon1, newMoon2 |
| )); |
| } |
| #endif |
| |
| return (newMoon2 >= newMoon1) && |
| (isLeapMonthBetween(newMoon1, newMoonNear(newMoon2 - SYNODIC_GAP, FALSE)) || |
| hasNoMajorSolarTerm(newMoon2)); |
| } |
| |
| /** |
| * Compute fields for the Chinese calendar system. This method can |
| * either set all relevant fields, as required by |
| * <code>handleComputeFields()</code>, or it can just set the MONTH and |
| * IS_LEAP_MONTH fields, as required by |
| * <code>handleComputeMonthStart()</code>. |
| * |
| * <p>As a side effect, this method sets {@link #isLeapYear}. |
| * @param days days after January 1, 1970 0:00 astronomical base zone |
| * of the date to compute fields for |
| * @param gyear the Gregorian year of the given date |
| * @param gmonth the Gregorian month of the given date |
| * @param setAllFields if true, set the EXTENDED_YEAR, ERA, YEAR, |
| * DAY_OF_MONTH, and DAY_OF_YEAR fields. In either case set the MONTH |
| * and IS_LEAP_MONTH fields. |
| */ |
| void ChineseCalendar::computeChineseFields(int32_t days, int32_t gyear, int32_t gmonth, |
| UBool setAllFields) { |
| |
| // Find the winter solstices before and after the target date. |
| // These define the boundaries of this Chinese year, specifically, |
| // the position of month 11, which always contains the solstice. |
| // We want solsticeBefore <= date < solsticeAfter. |
| int32_t solsticeBefore; |
| int32_t solsticeAfter = winterSolstice(gyear); |
| if (days < solsticeAfter) { |
| solsticeBefore = winterSolstice(gyear - 1); |
| } else { |
| solsticeBefore = solsticeAfter; |
| solsticeAfter = winterSolstice(gyear + 1); |
| } |
| |
| // Find the start of the month after month 11. This will be either |
| // the prior month 12 or leap month 11 (very rare). Also find the |
| // start of the following month 11. |
| int32_t firstMoon = newMoonNear(solsticeBefore + 1, TRUE); |
| int32_t lastMoon = newMoonNear(solsticeAfter + 1, FALSE); |
| int32_t thisMoon = newMoonNear(days + 1, FALSE); // Start of this month |
| // Note: isLeapYear is a member variable |
| isLeapYear = synodicMonthsBetween(firstMoon, lastMoon) == 12; |
| |
| int32_t month = synodicMonthsBetween(firstMoon, thisMoon); |
| if (isLeapYear && isLeapMonthBetween(firstMoon, thisMoon)) { |
| month--; |
| } |
| if (month < 1) { |
| month += 12; |
| } |
| |
| UBool isLeapMonth = isLeapYear && |
| hasNoMajorSolarTerm(thisMoon) && |
| !isLeapMonthBetween(firstMoon, newMoonNear(thisMoon - SYNODIC_GAP, FALSE)); |
| |
| internalSet(UCAL_MONTH, month-1); // Convert from 1-based to 0-based |
| internalSet(UCAL_IS_LEAP_MONTH, isLeapMonth?1:0); |
| |
| if (setAllFields) { |
| |
| // Extended year and cycle year is based on the epoch year |
| |
| int32_t extended_year = gyear - fEpochYear; |
| int cycle_year = gyear - CHINESE_EPOCH_YEAR; |
| if (month < 11 || |
| gmonth >= UCAL_JULY) { |
| extended_year++; |
| cycle_year++; |
| } |
| int32_t dayOfMonth = days - thisMoon + 1; |
| |
| internalSet(UCAL_EXTENDED_YEAR, extended_year); |
| |
| // 0->0,60 1->1,1 60->1,60 61->2,1 etc. |
| int32_t yearOfCycle; |
| int32_t cycle = ClockMath::floorDivide(cycle_year - 1, 60, yearOfCycle); |
| internalSet(UCAL_ERA, cycle + 1); |
| internalSet(UCAL_YEAR, yearOfCycle + 1); |
| |
| internalSet(UCAL_DAY_OF_MONTH, dayOfMonth); |
| |
| // Days will be before the first new year we compute if this |
| // date is in month 11, leap 11, 12. There is never a leap 12. |
| // New year computations are cached so this should be cheap in |
| // the long run. |
| int32_t theNewYear = newYear(gyear); |
| if (days < theNewYear) { |
| theNewYear = newYear(gyear-1); |
| } |
| internalSet(UCAL_DAY_OF_YEAR, days - theNewYear + 1); |
| } |
| } |
| |
| |
| //------------------------------------------------------------------ |
| // Fields to time |
| //------------------------------------------------------------------ |
| |
| /** |
| * Return the Chinese new year of the given Gregorian year. |
| * @param gyear a Gregorian year |
| * @return days after January 1, 1970 0:00 astronomical base zone of the |
| * Chinese new year of the given year (this will be a new moon) |
| */ |
| int32_t ChineseCalendar::newYear(int32_t gyear) const { |
| UErrorCode status = U_ZERO_ERROR; |
| int32_t cacheValue = CalendarCache::get(&gChineseCalendarNewYearCache, gyear, status); |
| |
| if (cacheValue == 0) { |
| |
| int32_t solsticeBefore= winterSolstice(gyear - 1); |
| int32_t solsticeAfter = winterSolstice(gyear); |
| int32_t newMoon1 = newMoonNear(solsticeBefore + 1, TRUE); |
| int32_t newMoon2 = newMoonNear(newMoon1 + SYNODIC_GAP, TRUE); |
| int32_t newMoon11 = newMoonNear(solsticeAfter + 1, FALSE); |
| |
| if (synodicMonthsBetween(newMoon1, newMoon11) == 12 && |
| (hasNoMajorSolarTerm(newMoon1) || hasNoMajorSolarTerm(newMoon2))) { |
| cacheValue = newMoonNear(newMoon2 + SYNODIC_GAP, TRUE); |
| } else { |
| cacheValue = newMoon2; |
| } |
| |
| CalendarCache::put(&gChineseCalendarNewYearCache, gyear, cacheValue, status); |
| } |
| if(U_FAILURE(status)) { |
| cacheValue = 0; |
| } |
| return cacheValue; |
| } |
| |
| /** |
| * Adjust this calendar to be delta months before or after a given |
| * start position, pinning the day of month if necessary. The start |
| * position is given as a local days number for the start of the month |
| * and a day-of-month. Used by add() and roll(). |
| * @param newMoon the local days of the first day of the month of the |
| * start position (days after January 1, 1970 0:00 Asia/Shanghai) |
| * @param dom the 1-based day-of-month of the start position |
| * @param delta the number of months to move forward or backward from |
| * the start position |
| */ |
| void ChineseCalendar::offsetMonth(int32_t newMoon, int32_t dom, int32_t delta) { |
| UErrorCode status = U_ZERO_ERROR; |
| |
| // Move to the middle of the month before our target month. |
| newMoon += (int32_t) (CalendarAstronomer::SYNODIC_MONTH * (delta - 0.5)); |
| |
| // Search forward to the target month's new moon |
| newMoon = newMoonNear(newMoon, TRUE); |
| |
| // Find the target dom |
| int32_t jd = newMoon + kEpochStartAsJulianDay - 1 + dom; |
| |
| // Pin the dom. In this calendar all months are 29 or 30 days |
| // so pinning just means handling dom 30. |
| if (dom > 29) { |
| set(UCAL_JULIAN_DAY, jd-1); |
| // TODO Fix this. We really shouldn't ever have to |
| // explicitly call complete(). This is either a bug in |
| // this method, in ChineseCalendar, or in |
| // Calendar.getActualMaximum(). I suspect the last. |
| complete(status); |
| if (U_FAILURE(status)) return; |
| if (getActualMaximum(UCAL_DAY_OF_MONTH, status) >= dom) { |
| if (U_FAILURE(status)) return; |
| set(UCAL_JULIAN_DAY, jd); |
| } |
| } else { |
| set(UCAL_JULIAN_DAY, jd); |
| } |
| } |
| |
| |
| UBool |
| ChineseCalendar::inDaylightTime(UErrorCode& status) const |
| { |
| // copied from GregorianCalendar |
| if (U_FAILURE(status) || !getTimeZone().useDaylightTime()) |
| return FALSE; |
| |
| // Force an update of the state of the Calendar. |
| ((ChineseCalendar*)this)->complete(status); // cast away const |
| |
| return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE); |
| } |
| |
| // default century |
| |
| static UDate gSystemDefaultCenturyStart = DBL_MIN; |
| static int32_t gSystemDefaultCenturyStartYear = -1; |
| static icu::UInitOnce gSystemDefaultCenturyInitOnce = U_INITONCE_INITIALIZER; |
| |
| |
| UBool ChineseCalendar::haveDefaultCentury() const |
| { |
| return TRUE; |
| } |
| |
| UDate ChineseCalendar::defaultCenturyStart() const |
| { |
| return internalGetDefaultCenturyStart(); |
| } |
| |
| int32_t ChineseCalendar::defaultCenturyStartYear() const |
| { |
| return internalGetDefaultCenturyStartYear(); |
| } |
| |
| static void U_CALLCONV initializeSystemDefaultCentury() |
| { |
| // initialize systemDefaultCentury and systemDefaultCenturyYear based |
| // on the current time. They'll be set to 80 years before |
| // the current time. |
| UErrorCode status = U_ZERO_ERROR; |
| ChineseCalendar calendar(Locale("@calendar=chinese"),status); |
| if (U_SUCCESS(status)) { |
| calendar.setTime(Calendar::getNow(), status); |
| calendar.add(UCAL_YEAR, -80, status); |
| gSystemDefaultCenturyStart = calendar.getTime(status); |
| gSystemDefaultCenturyStartYear = calendar.get(UCAL_YEAR, status); |
| } |
| // We have no recourse upon failure unless we want to propagate the failure |
| // out. |
| } |
| |
| UDate |
| ChineseCalendar::internalGetDefaultCenturyStart() const |
| { |
| // lazy-evaluate systemDefaultCenturyStart |
| umtx_initOnce(gSystemDefaultCenturyInitOnce, &initializeSystemDefaultCentury); |
| return gSystemDefaultCenturyStart; |
| } |
| |
| int32_t |
| ChineseCalendar::internalGetDefaultCenturyStartYear() const |
| { |
| // lazy-evaluate systemDefaultCenturyStartYear |
| umtx_initOnce(gSystemDefaultCenturyInitOnce, &initializeSystemDefaultCentury); |
| return gSystemDefaultCenturyStartYear; |
| } |
| |
| UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ChineseCalendar) |
| |
| U_NAMESPACE_END |
| |
| #endif |
| |
