icuSources/i18n/dangical.cpp

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4  ******************************************************************************
   5  * Copyright (C) 2013, International Business Machines Corporation
   6  * and others. All Rights Reserved.
   7  ******************************************************************************
   8  *
   9  * File DANGICAL.CPP
  10  *****************************************************************************
  11  */
  12
  13 #include "chnsecal.h"
  14 #include "dangical.h"
  15
  16 #if !UCONFIG_NO_FORMATTING
  17
  18 #include "gregoimp.h" // Math
  19 #include "uassert.h"
  20 #include "ucln_in.h"
  21 #include "umutex.h"
  22 #include "unicode/rbtz.h"
  23 #include "unicode/tzrule.h"
  24
  25 // --- The cache --
  26 static icu::TimeZone *gDangiCalendarZoneAstroCalc = NULL;
  27 static icu::UInitOnce gDangiCalendarInitOnce = U_INITONCE_INITIALIZER;
  28
  29 /**
  30  * The start year of the Korean traditional calendar (Dan-gi) is the inaugural
  31  * year of Dan-gun (BC 2333).
  32  */
  33 static const int32_t DANGI_EPOCH_YEAR = -2332; // Gregorian year
  34
  35 U_CDECL_BEGIN
  36 static UBool calendar_dangi_cleanup(void) {
  37     if (gDangiCalendarZoneAstroCalc) {
  38         delete gDangiCalendarZoneAstroCalc;
  39         gDangiCalendarZoneAstroCalc = NULL;
  40     }
  41     gDangiCalendarInitOnce.reset();
  42     return TRUE;
  43 }
  44 U_CDECL_END
  45
  46 U_NAMESPACE_BEGIN
  47
  48 // Implementation of the DangiCalendar class
  49
  50 //-------------------------------------------------------------------------
  51 // Constructors...
  52 //-------------------------------------------------------------------------
  53
  54 DangiCalendar::DangiCalendar(const Locale& aLocale, UErrorCode& success)
  55 :   ChineseCalendar(aLocale, DANGI_EPOCH_YEAR, getDangiCalZoneAstroCalc(), success)
  56 {
  57 }
  58
  59 DangiCalendar::DangiCalendar (const DangiCalendar& other)
  60 : ChineseCalendar(other)
  61 {
  62 }
  63
  64 DangiCalendar::~DangiCalendar()
  65 {
  66 }
  67
  68 Calendar*
  69 DangiCalendar::clone() const
  70 {
  71     return new DangiCalendar(*this);
  72 }
  73
  74 const char *DangiCalendar::getType() const {
  75     return "dangi";
  76 }
  77
  78 /**
  79  * The time zone used for performing astronomical computations for
  80  * Dangi calendar. In Korea various timezones have been used historically
  81  * (cf. http://www.math.snu.ac.kr/~kye/others/lunar.html):
  82  *
  83  *            - 1908/04/01: GMT+8
  84  * 1908/04/01 - 1911/12/31: GMT+8.5
  85  * 1912/01/01 - 1954/03/20: GMT+9
  86  * 1954/03/21 - 1961/08/09: GMT+8.5
  87  * 1961/08/10 -           : GMT+9
  88  *
  89  * Note that, in 1908-1911, the government did not apply the timezone change
  90  * but used GMT+8. In addition, 1954-1961's timezone change does not affect
  91  * the lunar date calculation. Therefore, the following simpler rule works:
  92  *
  93  * -1911: GMT+8
  94  * 1912-: GMT+9
  95  *
  96  * Unfortunately, our astronomer's approximation doesn't agree with the
  97  * references (http://www.math.snu.ac.kr/~kye/others/lunar.html and
  98  * http://astro.kasi.re.kr/Life/ConvertSolarLunarForm.aspx?MenuID=115)
  99  * in 1897/7/30. So the following ad hoc fix is used here:
 100  *
 101  *     -1896: GMT+8
 102  *      1897: GMT+7
 103  * 1898-1911: GMT+8
 104  * 1912-    : GMT+9
 105  */
 106 static void U_CALLCONV initDangiCalZoneAstroCalc(void) {
 107     U_ASSERT(gDangiCalendarZoneAstroCalc == NULL);
 108     const UDate millis1897[] = { (UDate)((1897 - 1970) * 365 * kOneDay) }; // some days of error is not a problem here
 109     const UDate millis1898[] = { (UDate)((1898 - 1970) * 365 * kOneDay) }; // some days of error is not a problem here
 110     const UDate millis1912[] = { (UDate)((1912 - 1970) * 365 * kOneDay) }; // this doesn't create an issue for 1911/12/20
 111     InitialTimeZoneRule* initialTimeZone = new InitialTimeZoneRule(UNICODE_STRING_SIMPLE("GMT+8"), 8*kOneHour, 0);
 112     TimeZoneRule* rule1897 = new TimeArrayTimeZoneRule(UNICODE_STRING_SIMPLE("Korean 1897"), 7*kOneHour, 0, millis1897, 1, DateTimeRule::STANDARD_TIME);
 113     TimeZoneRule* rule1898to1911 = new TimeArrayTimeZoneRule(UNICODE_STRING_SIMPLE("Korean 1898-1911"), 8*kOneHour, 0, millis1898, 1, DateTimeRule::STANDARD_TIME);
 114     TimeZoneRule* ruleFrom1912 = new TimeArrayTimeZoneRule(UNICODE_STRING_SIMPLE("Korean 1912-"), 9*kOneHour, 0, millis1912, 1, DateTimeRule::STANDARD_TIME);
 115     UErrorCode status = U_ZERO_ERROR;
 116     RuleBasedTimeZone* dangiCalZoneAstroCalc = new RuleBasedTimeZone(UNICODE_STRING_SIMPLE("KOREA_ZONE"), initialTimeZone); // adopts initialTimeZone
 117     dangiCalZoneAstroCalc->addTransitionRule(rule1897, status); // adopts rule1897
 118     dangiCalZoneAstroCalc->addTransitionRule(rule1898to1911, status);
 119     dangiCalZoneAstroCalc->addTransitionRule(ruleFrom1912, status);
 120     dangiCalZoneAstroCalc->complete(status);
 121     if (U_SUCCESS(status)) {
 122         gDangiCalendarZoneAstroCalc = dangiCalZoneAstroCalc;
 123     } else {
 124         delete dangiCalZoneAstroCalc;
 125         gDangiCalendarZoneAstroCalc = NULL;
 126     }
 127     ucln_i18n_registerCleanup(UCLN_I18N_DANGI_CALENDAR, calendar_dangi_cleanup);
 128 }
 129
 130 const TimeZone* DangiCalendar::getDangiCalZoneAstroCalc(void) const {
 131     umtx_initOnce(gDangiCalendarInitOnce, &initDangiCalZoneAstroCalc);
 132     return gDangiCalendarZoneAstroCalc;
 133 }
 134
 135
 136 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(DangiCalendar)
 137
 138 U_NAMESPACE_END
 139
 140 #endif
 141