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      1 /*
      2 ******************************************************************************
      3 * Copyright (C) 2003-2013, International Business Machines Corporation
      4 * and others. All Rights Reserved.
      5 ******************************************************************************
      6 *
      7 * File HEBRWCAL.H
      8 *
      9 * Modification History:
     10 *
     11 *   Date        Name        Description
     12 *   05/13/2003  srl          copied from gregocal.h
     13 *   11/26/2003  srl          copied from buddhcal.h
     14 ******************************************************************************
     15 */
     16 
     17 #ifndef HEBRWCAL_H
     18 #define HEBRWCAL_H
     19 
     20 #include "unicode/utypes.h"
     21 
     22 #if !UCONFIG_NO_FORMATTING
     23 
     24 #include "unicode/calendar.h"
     25 #include "unicode/gregocal.h"
     26 
     27 U_NAMESPACE_BEGIN
     28 
     29 /**
     30  * <code>HebrewCalendar</code> is a subclass of <code>Calendar</code>
     31  * that that implements the traditional Hebrew calendar.
     32  * This is the civil calendar in Israel and the liturgical calendar
     33  * of the Jewish faith worldwide.
     34  * <p>
     35  * The Hebrew calendar is lunisolar and thus has a number of interesting
     36  * properties that distinguish it from the Gregorian.  Months start
     37  * on the day of (an arithmetic approximation of) each new moon.  Since the
     38  * solar year (approximately 365.24 days) is not an even multiple of
     39  * the lunar month (approximately 29.53 days) an extra "leap month" is
     40  * inserted in 7 out of every 19 years.  To make matters even more
     41  * interesting, the start of a year can be delayed by up to three days
     42  * in order to prevent certain holidays from falling on the Sabbath and
     43  * to prevent certain illegal year lengths.  Finally, the lengths of certain
     44  * months can vary depending on the number of days in the year.
     45  * <p>
     46  * The leap month is known as "Adar 1" and is inserted between the
     47  * months of Shevat and Adar in leap years.  Since the leap month does
     48  * not come at the end of the year, calculations involving
     49  * month numbers are particularly complex.  Users of this class should
     50  * make sure to use the {@link #roll roll} and {@link #add add} methods
     51  * rather than attempting to perform date arithmetic by manipulating
     52  * the fields directly.
     53  * <p>
     54  * <b>Note:</b> In the traditional Hebrew calendar, days start at sunset.
     55  * However, in order to keep the time fields in this class
     56  * synchronized with those of the other calendars and with local clock time,
     57  * we treat days and months as beginning at midnight,
     58  * roughly 6 hours after the corresponding sunset.
     59  * <p>
     60  * If you are interested in more information on the rules behind the Hebrew
     61  * calendar, see one of the following references:
     62  * <ul>
     63  * <li>"<a href="http://www.amazon.com/exec/obidos/ASIN/0521564743">Calendrical Calculations</a>",
     64  *      by Nachum Dershowitz & Edward Reingold, Cambridge University Press, 1997, pages 85-91.
     65  *
     66  * <li>Hebrew Calendar Science and Myths,
     67  *      <a href="http://www.geocities.com/Athens/1584/">
     68  *      http://www.geocities.com/Athens/1584/</a>
     69  *
     70  * <li>The Calendar FAQ,
     71  *      <a href="http://www.faqs.org/faqs/calendars/faq/">
     72  *      http://www.faqs.org/faqs/calendars/faq/</a>
     73  * </ul>
     74  * <p>
     75  * @see com.ibm.icu.util.GregorianCalendar
     76  *
     77  * @author Laura Werner
     78  * @author Alan Liu
     79  * @author Steven R. Loomis
     80  * <p>
     81  * @internal
     82  */
     83 class U_I18N_API HebrewCalendar : public Calendar {
     84 public:
     85   /**
     86    * Useful constants for HebrewCalendar.
     87    * @internal
     88    */
     89   enum EEras {
     90     /**
     91      * Constant for Tishri, the 1st month of the Hebrew year.
     92      */
     93       TISHRI,
     94       /**
     95      * Constant for Heshvan, the 2nd month of the Hebrew year.
     96      */
     97       HESHVAN,
     98       /**
     99      * Constant for Kislev, the 3rd month of the Hebrew year.
    100      */
    101       KISLEV,
    102 
    103     /**
    104      * Constant for Tevet, the 4th month of the Hebrew year.
    105      */
    106       TEVET,
    107 
    108     /**
    109      * Constant for Shevat, the 5th month of the Hebrew year.
    110      */
    111       SHEVAT,
    112 
    113     /**
    114      * Constant for Adar I, the 6th month of the Hebrew year
    115      * (present in leap years only). In non-leap years, the calendar
    116      * jumps from Shevat (5th month) to Adar (7th month).
    117      */
    118       ADAR_1,
    119 
    120     /**
    121      * Constant for the Adar, the 7th month of the Hebrew year.
    122      */
    123       ADAR,
    124 
    125     /**
    126      * Constant for Nisan, the 8th month of the Hebrew year.
    127      */
    128       NISAN,
    129 
    130     /**
    131      * Constant for Iyar, the 9th month of the Hebrew year.
    132      */
    133       IYAR,
    134 
    135     /**
    136      * Constant for Sivan, the 10th month of the Hebrew year.
    137      */
    138       SIVAN,
    139 
    140     /**
    141      * Constant for Tammuz, the 11th month of the Hebrew year.
    142      */
    143       TAMUZ,
    144 
    145     /**
    146      * Constant for Av, the 12th month of the Hebrew year.
    147      */
    148       AV,
    149 
    150     /**
    151      * Constant for Elul, the 13th month of the Hebrew year.
    152      */
    153       ELUL
    154     };
    155 
    156     /**
    157      * Constructs a HebrewCalendar based on the current time in the default time zone
    158      * with the given locale.
    159      *
    160      * @param aLocale  The given locale.
    161      * @param success  Indicates the status of HebrewCalendar object construction.
    162      *                 Returns U_ZERO_ERROR if constructed successfully.
    163      * @internal
    164      */
    165     HebrewCalendar(const Locale& aLocale, UErrorCode& success);
    166 
    167 
    168     /**
    169      * Destructor
    170      * @internal
    171      */
    172     virtual ~HebrewCalendar();
    173 
    174     /**
    175      * Copy constructor
    176      * @param source    the object to be copied.
    177      * @internal
    178      */
    179     HebrewCalendar(const HebrewCalendar& source);
    180 
    181     /**
    182      * Default assignment operator
    183      * @param right    the object to be copied.
    184      * @internal
    185      */
    186     HebrewCalendar& operator=(const HebrewCalendar& right);
    187 
    188     /**
    189      * Create and return a polymorphic copy of this calendar.
    190      * @return    return a polymorphic copy of this calendar.
    191      * @internal
    192      */
    193     virtual Calendar* clone(void) const;
    194 
    195 public:
    196     /**
    197      * Override Calendar Returns a unique class ID POLYMORPHICALLY. Pure virtual
    198      * override. This method is to implement a simple version of RTTI, since not all C++
    199      * compilers support genuine RTTI. Polymorphic operator==() and clone() methods call
    200      * this method.
    201      *
    202      * @return   The class ID for this object. All objects of a given class have the
    203      *           same class ID. Objects of other classes have different class IDs.
    204      * @internal
    205      */
    206     virtual UClassID getDynamicClassID(void) const;
    207 
    208     /**
    209      * Return the class ID for this class. This is useful only for comparing to a return
    210      * value from getDynamicClassID(). For example:
    211      *
    212      *      Base* polymorphic_pointer = createPolymorphicObject();
    213      *      if (polymorphic_pointer->getDynamicClassID() ==
    214      *          Derived::getStaticClassID()) ...
    215      *
    216      * @return   The class ID for all objects of this class.
    217      * @internal
    218      */
    219     static UClassID U_EXPORT2 getStaticClassID(void);
    220 
    221     /**
    222      * return the calendar type, "hebrew".
    223      *
    224      * @return calendar type
    225      * @internal
    226      */
    227     virtual const char * getType() const;
    228 
    229 
    230     // Calendar API
    231  public:
    232     /**
    233      * (Overrides Calendar) UDate Arithmetic function. Adds the specified (signed) amount
    234      * of time to the given time field, based on the calendar's rules.  For more
    235      * information, see the documentation for Calendar::add().
    236      *
    237      * @param field   The time field.
    238      * @param amount  The amount of date or time to be added to the field.
    239      * @param status  Output param set to success/failure code on exit. If any value
    240      *                previously set in the time field is invalid, this will be set to
    241      *                an error status.
    242      */
    243     virtual void add(UCalendarDateFields field, int32_t amount, UErrorCode& status);
    244     /**
    245      * @deprecated ICU 2.6 use UCalendarDateFields instead of EDateFields
    246      */
    247     virtual void add(EDateFields field, int32_t amount, UErrorCode& status);
    248 
    249 
    250     /**
    251      * (Overrides Calendar) Rolls up or down by the given amount in the specified field.
    252      * For more information, see the documentation for Calendar::roll().
    253      *
    254      * @param field   The time field.
    255      * @param amount  Indicates amount to roll.
    256      * @param status  Output param set to success/failure code on exit. If any value
    257      *                previously set in the time field is invalid, this will be set to
    258      *                an error status.
    259      * @internal
    260      */
    261     virtual void roll(UCalendarDateFields field, int32_t amount, UErrorCode& status);
    262 
    263     /**
    264      * (Overrides Calendar) Rolls up or down by the given amount in the specified field.
    265      * For more information, see the documentation for Calendar::roll().
    266      *
    267      * @param field   The time field.
    268      * @param amount  Indicates amount to roll.
    269      * @param status  Output param set to success/failure code on exit. If any value
    270      *                previously set in the time field is invalid, this will be set to
    271      *                an error status.
    272      * @deprecated ICU 2.6. Use roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) instead.
    273 `     */
    274     virtual void roll(EDateFields field, int32_t amount, UErrorCode& status);
    275 
    276     /**
    277      * @internal
    278      */
    279     static UBool isLeapYear(int32_t year) ;
    280 
    281  protected:
    282 
    283     /**
    284      * Subclass API for defining limits of different types.
    285      * Subclasses must implement this method to return limits for the
    286      * following fields:
    287      *
    288      * <pre>UCAL_ERA
    289      * UCAL_YEAR
    290      * UCAL_MONTH
    291      * UCAL_WEEK_OF_YEAR
    292      * UCAL_WEEK_OF_MONTH
    293      * UCAL_DATE (DAY_OF_MONTH on Java)
    294      * UCAL_DAY_OF_YEAR
    295      * UCAL_DAY_OF_WEEK_IN_MONTH
    296      * UCAL_YEAR_WOY
    297      * UCAL_EXTENDED_YEAR</pre>
    298      *
    299      * @param field one of the above field numbers
    300      * @param limitType one of <code>MINIMUM</code>, <code>GREATEST_MINIMUM</code>,
    301      * <code>LEAST_MAXIMUM</code>, or <code>MAXIMUM</code>
    302      * @internal
    303      */
    304     virtual int32_t handleGetLimit(UCalendarDateFields field, ELimitType limitType) const;
    305 
    306     /**
    307      * Return the number of days in the given month of the given extended
    308      * year of this calendar system.  Subclasses should override this
    309      * method if they can provide a more correct or more efficient
    310      * implementation than the default implementation in Calendar.
    311      * @internal
    312      */
    313     virtual int32_t handleGetMonthLength(int32_t extendedYear, int32_t month) const;
    314 
    315     /**
    316      * Return the number of days in the given extended year of this
    317      * calendar system.  Subclasses should override this method if they can
    318      * provide a more correct or more efficient implementation than the
    319      * default implementation in Calendar.
    320      * @stable ICU 2.0
    321      */
    322     virtual int32_t handleGetYearLength(int32_t eyear) const;
    323     /**
    324      * Subclasses may override this method to compute several fields
    325      * specific to each calendar system.  These are:
    326      *
    327      * <ul><li>ERA
    328      * <li>YEAR
    329      * <li>MONTH
    330      * <li>DAY_OF_MONTH
    331      * <li>DAY_OF_YEAR
    332      * <li>EXTENDED_YEAR</ul>
    333      *
    334      * <p>The GregorianCalendar implementation implements
    335      * a calendar with the specified Julian/Gregorian cutover date.
    336      * @internal
    337      */
    338     virtual void handleComputeFields(int32_t julianDay, UErrorCode &status);
    339     /**
    340      * Return the extended year defined by the current fields.  This will
    341      * use the UCAL_EXTENDED_YEAR field or the UCAL_YEAR and supra-year fields (such
    342      * as UCAL_ERA) specific to the calendar system, depending on which set of
    343      * fields is newer.
    344      * @return the extended year
    345      * @internal
    346      */
    347     virtual int32_t handleGetExtendedYear();
    348     /**
    349      * Return the Julian day number of day before the first day of the
    350      * given month in the given extended year.  Subclasses should override
    351      * this method to implement their calendar system.
    352      * @param eyear the extended year
    353      * @param month the zero-based month, or 0 if useMonth is false
    354      * @param useMonth if false, compute the day before the first day of
    355      * the given year, otherwise, compute the day before the first day of
    356      * the given month
    357      * @param return the Julian day number of the day before the first
    358      * day of the given month and year
    359      * @internal
    360      */
    361     virtual int32_t handleComputeMonthStart(int32_t eyear, int32_t month,
    362                                                    UBool useMonth) const;
    363 
    364 
    365     /**
    366      * Validate a single field of this calendar.
    367      * Overrides Calendar::validateField(int) to provide
    368      * special handling for month validation for Hebrew calendar.
    369      * @internal
    370      */
    371     virtual void validateField(UCalendarDateFields field, UErrorCode &status);
    372 
    373  protected:
    374 
    375   /**
    376    * (Overrides Calendar) Return true if the current date for this Calendar is in
    377    * Daylight Savings Time. Recognizes DST_OFFSET, if it is set.
    378    *
    379    * @param status Fill-in parameter which receives the status of this operation.
    380    * @return   True if the current date for this Calendar is in Daylight Savings Time,
    381    *           false, otherwise.
    382    * @internal
    383    */
    384   virtual UBool inDaylightTime(UErrorCode& status) const;
    385 
    386     /**
    387      * Returns TRUE because the Hebrew Calendar does have a default century
    388      * @internal
    389      */
    390     virtual UBool haveDefaultCentury() const;
    391 
    392     /**
    393      * Returns the date of the start of the default century
    394      * @return start of century - in milliseconds since epoch, 1970
    395      * @internal
    396      */
    397     virtual UDate defaultCenturyStart() const;
    398 
    399     /**
    400      * Returns the year in which the default century begins
    401      * @internal
    402      */
    403     virtual int32_t defaultCenturyStartYear() const;
    404 
    405  private: // Calendar-specific implementation
    406     /**
    407      * Finds the day # of the first day in the given Hebrew year.
    408      * To do this, we want to calculate the time of the Tishri 1 new moon
    409      * in that year.
    410      * <p>
    411      * The algorithm here is similar to ones described in a number of
    412      * references, including:
    413      * <ul>
    414      * <li>"Calendrical Calculations", by Nachum Dershowitz & Edward Reingold,
    415      *     Cambridge University Press, 1997, pages 85-91.
    416      *
    417      * <li>Hebrew Calendar Science and Myths,
    418      *     <a href="http://www.geocities.com/Athens/1584/">
    419      *     http://www.geocities.com/Athens/1584/</a>
    420      *
    421      * <li>The Calendar FAQ,
    422      *      <a href="http://www.faqs.org/faqs/calendars/faq/">
    423      *      http://www.faqs.org/faqs/calendars/faq/</a>
    424      * </ul>
    425      * @param year extended year
    426      * @return day number (JD)
    427      * @internal
    428      */
    429     static int32_t startOfYear(int32_t year, UErrorCode& status);
    430 
    431     static int32_t absoluteDayToDayOfWeek(int32_t day) ;
    432 
    433     /**
    434      * @internal
    435      */
    436     int32_t yearType(int32_t year) const;
    437 
    438     /**
    439      * @internal
    440      */
    441     static int32_t monthsInYear(int32_t year) ;
    442 };
    443 
    444 U_NAMESPACE_END
    445 
    446 #endif /* #if !UCONFIG_NO_FORMATTING */
    447 
    448 #endif
    449 //eof
    450 
    451