1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/intl/icu/source/i18n/chnsecal.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,281 @@
1.4 +/*
1.5 + *****************************************************************************
1.6 + * Copyright (C) 2007-2013, International Business Machines Corporation
1.7 + * and others. All Rights Reserved.
1.8 + *****************************************************************************
1.9 + *
1.10 + * File CHNSECAL.H
1.11 + *
1.12 + * Modification History:
1.13 + *
1.14 + * Date Name Description
1.15 + * 9/18/2007 ajmacher ported from java ChineseCalendar
1.16 + *****************************************************************************
1.17 + */
1.18 +
1.19 +#ifndef CHNSECAL_H
1.20 +#define CHNSECAL_H
1.21 +
1.22 +#include "unicode/utypes.h"
1.23 +
1.24 +#if !UCONFIG_NO_FORMATTING
1.25 +
1.26 +#include "unicode/calendar.h"
1.27 +#include "unicode/timezone.h"
1.28 +
1.29 +U_NAMESPACE_BEGIN
1.30 +
1.31 +/**
1.32 + * <code>ChineseCalendar</code> is a concrete subclass of {@link Calendar}
1.33 + * that implements a traditional Chinese calendar. The traditional Chinese
1.34 + * calendar is a lunisolar calendar: Each month starts on a new moon, and
1.35 + * the months are numbered according to solar events, specifically, to
1.36 + * guarantee that month 11 always contains the winter solstice. In order
1.37 + * to accomplish this, leap months are inserted in certain years. Leap
1.38 + * months are numbered the same as the month they follow. The decision of
1.39 + * which month is a leap month depends on the relative movements of the sun
1.40 + * and moon.
1.41 + *
1.42 + * <p>This class defines one addition field beyond those defined by
1.43 + * <code>Calendar</code>: The <code>IS_LEAP_MONTH</code> field takes the
1.44 + * value of 0 for normal months, or 1 for leap months.
1.45 + *
1.46 + * <p>All astronomical computations are performed with respect to a time
1.47 + * zone of GMT+8:00 and a longitude of 120 degrees east. Although some
1.48 + * calendars implement a historically more accurate convention of using
1.49 + * Beijing's local longitude (116 degrees 25 minutes east) and time zone
1.50 + * (GMT+7:45:40) for dates before 1929, we do not implement this here.
1.51 + *
1.52 + * <p>Years are counted in two different ways in the Chinese calendar. The
1.53 + * first method is by sequential numbering from the 61st year of the reign
1.54 + * of Huang Di, 2637 BCE, which is designated year 1 on the Chinese
1.55 + * calendar. The second method uses 60-year cycles from the same starting
1.56 + * point, which is designated year 1 of cycle 1. In this class, the
1.57 + * <code>EXTENDED_YEAR</code> field contains the sequential year count.
1.58 + * The <code>ERA</code> field contains the cycle number, and the
1.59 + * <code>YEAR</code> field contains the year of the cycle, a value between
1.60 + * 1 and 60.
1.61 + *
1.62 + * <p>There is some variation in what is considered the starting point of
1.63 + * the calendar, with some sources starting in the first year of the reign
1.64 + * of Huang Di, rather than the 61st. This gives continuous year numbers
1.65 + * 60 years greater and cycle numbers one greater than what this class
1.66 + * implements.
1.67 + *
1.68 + * <p>Because <code>ChineseCalendar</code> defines an additional field and
1.69 + * redefines the way the <code>ERA</code> field is used, it requires a new
1.70 + * format class, <code>ChineseDateFormat</code>. As always, use the
1.71 + * methods <code>DateFormat.getXxxInstance(Calendar cal,...)</code> to
1.72 + * obtain a formatter for this calendar.
1.73 + *
1.74 + * <p>References:<ul>
1.75 + *
1.76 + * <li>Dershowitz and Reingold, <i>Calendrical Calculations</i>,
1.77 + * Cambridge University Press, 1997</li>
1.78 + *
1.79 + * <li>Helmer Aslaksen's
1.80 + * <a href="http://www.math.nus.edu.sg/aslaksen/calendar/chinese.shtml">
1.81 + * Chinese Calendar page</a></li>
1.82 + *
1.83 + * <li>The <a href="http://www.tondering.dk/claus/calendar.html">
1.84 + * Calendar FAQ</a></li>
1.85 + *
1.86 + * </ul>
1.87 + *
1.88 + * <p>
1.89 + * This class should only be subclassed to implement variants of the Chinese lunar calendar.</p>
1.90 + * <p>
1.91 + * ChineseCalendar usually should be instantiated using
1.92 + * {@link com.ibm.icu.util.Calendar#getInstance(ULocale)} passing in a <code>ULocale</code>
1.93 + * with the tag <code>"@calendar=chinese"</code>.</p>
1.94 + *
1.95 + * @see com.ibm.icu.text.ChineseDateFormat
1.96 + * @see com.ibm.icu.util.Calendar
1.97 + * @author Alan Liu
1.98 + * @internal
1.99 + */
1.100 +class U_I18N_API ChineseCalendar : public Calendar {
1.101 + public:
1.102 + //-------------------------------------------------------------------------
1.103 + // Constructors...
1.104 + //-------------------------------------------------------------------------
1.105 +
1.106 + /**
1.107 + * Constructs a ChineseCalendar based on the current time in the default time zone
1.108 + * with the given locale.
1.109 + *
1.110 + * @param aLocale The given locale.
1.111 + * @param success Indicates the status of ChineseCalendar object construction.
1.112 + * Returns U_ZERO_ERROR if constructed successfully.
1.113 + * @internal
1.114 + */
1.115 + ChineseCalendar(const Locale& aLocale, UErrorCode &success);
1.116 +
1.117 + protected:
1.118 +
1.119 + /**
1.120 + * Constructs a ChineseCalendar based on the current time in the default time zone
1.121 + * with the given locale, using the specified epoch year and time zone for
1.122 + * astronomical calculations.
1.123 + *
1.124 + * @param aLocale The given locale.
1.125 + * @param epochYear The epoch year to use for calculation.
1.126 + * @param zoneAstroCalc The TimeZone to use for astronomical calculations. If null,
1.127 + * will be set appropriately for Chinese calendar (UTC + 8:00).
1.128 + * @param success Indicates the status of ChineseCalendar object construction;
1.129 + * if successful, will not be changed to an error value.
1.130 + * @internal
1.131 + */
1.132 + ChineseCalendar(const Locale& aLocale, int32_t epochYear, const TimeZone* zoneAstroCalc, UErrorCode &success);
1.133 +
1.134 + public:
1.135 + /**
1.136 + * Copy Constructor
1.137 + * @internal
1.138 + */
1.139 + ChineseCalendar(const ChineseCalendar& other);
1.140 +
1.141 + /**
1.142 + * Destructor.
1.143 + * @internal
1.144 + */
1.145 + virtual ~ChineseCalendar();
1.146 +
1.147 + // clone
1.148 + virtual Calendar* clone() const;
1.149 +
1.150 + private:
1.151 +
1.152 + //-------------------------------------------------------------------------
1.153 + // Internal data....
1.154 + //-------------------------------------------------------------------------
1.155 +
1.156 + UBool isLeapYear;
1.157 + int32_t fEpochYear; // Start year of this Chinese calendar instance.
1.158 + const TimeZone* fZoneAstroCalc; // Zone used for the astronomical calculation
1.159 + // of this Chinese calendar instance.
1.160 +
1.161 + //----------------------------------------------------------------------
1.162 + // Calendar framework
1.163 + //----------------------------------------------------------------------
1.164 +
1.165 + protected:
1.166 + virtual int32_t handleGetLimit(UCalendarDateFields field, ELimitType limitType) const;
1.167 + virtual int32_t handleGetMonthLength(int32_t extendedYear, int32_t month) const;
1.168 + virtual int32_t handleComputeMonthStart(int32_t eyear, int32_t month, UBool useMonth) const;
1.169 + virtual int32_t handleGetExtendedYear();
1.170 + virtual void handleComputeFields(int32_t julianDay, UErrorCode &status);
1.171 + virtual const UFieldResolutionTable* getFieldResolutionTable() const;
1.172 +
1.173 + public:
1.174 + virtual void add(UCalendarDateFields field, int32_t amount, UErrorCode &status);
1.175 + virtual void add(EDateFields field, int32_t amount, UErrorCode &status);
1.176 + virtual void roll(UCalendarDateFields field, int32_t amount, UErrorCode &status);
1.177 + virtual void roll(EDateFields field, int32_t amount, UErrorCode &status);
1.178 +
1.179 + //----------------------------------------------------------------------
1.180 + // Internal methods & astronomical calculations
1.181 + //----------------------------------------------------------------------
1.182 +
1.183 + private:
1.184 +
1.185 + static const UFieldResolutionTable CHINESE_DATE_PRECEDENCE[];
1.186 +
1.187 + double daysToMillis(double days) const;
1.188 + double millisToDays(double millis) const;
1.189 + virtual int32_t winterSolstice(int32_t gyear) const;
1.190 + virtual int32_t newMoonNear(double days, UBool after) const;
1.191 + virtual int32_t synodicMonthsBetween(int32_t day1, int32_t day2) const;
1.192 + virtual int32_t majorSolarTerm(int32_t days) const;
1.193 + virtual UBool hasNoMajorSolarTerm(int32_t newMoon) const;
1.194 + virtual UBool isLeapMonthBetween(int32_t newMoon1, int32_t newMoon2) const;
1.195 + virtual void computeChineseFields(int32_t days, int32_t gyear,
1.196 + int32_t gmonth, UBool setAllFields);
1.197 + virtual int32_t newYear(int32_t gyear) const;
1.198 + virtual void offsetMonth(int32_t newMoon, int32_t dom, int32_t delta);
1.199 + const TimeZone* getChineseCalZoneAstroCalc(void) const;
1.200 +
1.201 + // UObject stuff
1.202 + public:
1.203 + /**
1.204 + * @return The class ID for this object. All objects of a given class have the
1.205 + * same class ID. Objects of other classes have different class IDs.
1.206 + * @internal
1.207 + */
1.208 + virtual UClassID getDynamicClassID(void) const;
1.209 +
1.210 + /**
1.211 + * Return the class ID for this class. This is useful only for comparing to a return
1.212 + * value from getDynamicClassID(). For example:
1.213 + *
1.214 + * Base* polymorphic_pointer = createPolymorphicObject();
1.215 + * if (polymorphic_pointer->getDynamicClassID() ==
1.216 + * Derived::getStaticClassID()) ...
1.217 + *
1.218 + * @return The class ID for all objects of this class.
1.219 + * @internal
1.220 + */
1.221 + static UClassID U_EXPORT2 getStaticClassID(void);
1.222 +
1.223 + /**
1.224 + * return the calendar type, "chinese".
1.225 + *
1.226 + * @return calendar type
1.227 + * @internal
1.228 + */
1.229 + virtual const char * getType() const;
1.230 +
1.231 +
1.232 + protected:
1.233 + /**
1.234 + * (Overrides Calendar) Return true if the current date for this Calendar is in
1.235 + * Daylight Savings Time. Recognizes DST_OFFSET, if it is set.
1.236 + *
1.237 + * @param status Fill-in parameter which receives the status of this operation.
1.238 + * @return True if the current date for this Calendar is in Daylight Savings Time,
1.239 + * false, otherwise.
1.240 + * @internal
1.241 + */
1.242 + virtual UBool inDaylightTime(UErrorCode& status) const;
1.243 +
1.244 +
1.245 + /**
1.246 + * Returns TRUE because the Islamic Calendar does have a default century
1.247 + * @internal
1.248 + */
1.249 + virtual UBool haveDefaultCentury() const;
1.250 +
1.251 + /**
1.252 + * Returns the date of the start of the default century
1.253 + * @return start of century - in milliseconds since epoch, 1970
1.254 + * @internal
1.255 + */
1.256 + virtual UDate defaultCenturyStart() const;
1.257 +
1.258 + /**
1.259 + * Returns the year in which the default century begins
1.260 + * @internal
1.261 + */
1.262 + virtual int32_t defaultCenturyStartYear() const;
1.263 +
1.264 + private: // default century stuff.
1.265 +
1.266 + /**
1.267 + * Returns the beginning date of the 100-year window that dates
1.268 + * with 2-digit years are considered to fall within.
1.269 + */
1.270 + UDate internalGetDefaultCenturyStart(void) const;
1.271 +
1.272 + /**
1.273 + * Returns the first year of the 100-year window that dates with
1.274 + * 2-digit years are considered to fall within.
1.275 + */
1.276 + int32_t internalGetDefaultCenturyStartYear(void) const;
1.277 +
1.278 + ChineseCalendar(); // default constructor not implemented
1.279 +};
1.280 +
1.281 +U_NAMESPACE_END
1.282 +
1.283 +#endif
1.284 +#endif
