Module java.base

Class HijrahChronology

  • All Implemented Interfaces:
    Serializable, Comparable<Chronology>, Chronology

    public final class HijrahChronology
    extends AbstractChronology
    implements Serializable
    The Hijrah calendar is a lunar calendar supporting Islamic calendars.

    The HijrahChronology follows the rules of the Hijrah calendar system. The Hijrah calendar has several variants based on differences in when the new moon is determined to have occurred and where the observation is made. In some variants the length of each month is computed algorithmically from the astronomical data for the moon and earth and in others the length of the month is determined by an authorized sighting of the new moon. For the algorithmically based calendars the calendar can project into the future. For sighting based calendars only historical data from past sightings is available.

    The length of each month is 29 or 30 days. Ordinary years have 354 days; leap years have 355 days.

    CLDR and LDML identify variants:

    Variants of Hijrah Calendars
    Chronology ID Calendar Type Locale extension, see Locale Description
    Hijrah-umalqura islamic-umalqura ca-islamic-umalqura Islamic - Umm Al-Qura calendar of Saudi Arabia

    Additional variants may be available through Chronology.getAvailableChronologies().

    Example

    Selecting the chronology from the locale uses Chronology.ofLocale(java.util.Locale) to find the Chronology based on Locale supported BCP 47 extension mechanism to request a specific calendar ("ca"). For example,

          Locale locale = Locale.forLanguageTag("en-US-u-ca-islamic-umalqura");
          Chronology chrono = Chronology.ofLocale(locale);
     
    Implementation Requirements:
    This class is immutable and thread-safe.
    Implementation Note:
    Each Hijrah variant is configured individually. Each variant is defined by a property resource that defines the ID, the calendar type, the start of the calendar, the alignment with the ISO calendar, and the length of each month for a range of years. The variants are loaded by HijrahChronology as a resource from hijrah-config-<calendar type>.properties.

    The Hijrah property resource is a set of properties that describe the calendar. The syntax is defined by java.util.Properties#load(Reader).

    Configuration of Hijrah Calendar
    Property Name Property value Description
    id Chronology Id, for example, "Hijrah-umalqura" The Id of the calendar in common usage
    type Calendar type, for example, "islamic-umalqura" LDML defines the calendar types
    version Version, for example: "1.8.0_1" The version of the Hijrah variant data
    iso-start ISO start date, formatted as yyyy-MM-dd, for example: "1900-04-30" The ISO date of the first day of the minimum Hijrah year.
    yyyy - a numeric 4 digit year, for example "1434" The value is a sequence of 12 month lengths, for example: "29 30 29 30 29 30 30 30 29 30 29 29" The lengths of the 12 months of the year separated by whitespace. A numeric year property must be present for every year without any gaps. The month lengths must be between 29-32 inclusive.
    Since:
    1.8
    See Also:
    Serialized Form
    • Method Detail

      • getCalendarType

        public String getCalendarType()
        Gets the calendar type of the Islamic calendar.

        The calendar type is an identifier defined by the Unicode Locale Data Markup Language (LDML) specification. It can be used to lookup the Chronology using Chronology.of(String).

        Specified by:
        getCalendarType in interface Chronology
        Returns:
        the calendar system type; non-null if the calendar has a standard type, otherwise null
        See Also:
        getId()
      • date

        public HijrahDate date​(Era era,
                               int yearOfEra,
                               int month,
                               int dayOfMonth)
        Obtains a local date in Hijrah calendar system from the era, year-of-era, month-of-year and day-of-month fields.
        Specified by:
        date in interface Chronology
        Parameters:
        era - the Hijrah era, not null
        yearOfEra - the year-of-era
        month - the month-of-year
        dayOfMonth - the day-of-month
        Returns:
        the Hijrah local date, not null
        Throws:
        DateTimeException - if unable to create the date
        ClassCastException - if the era is not a HijrahEra
      • date

        public HijrahDate date​(int prolepticYear,
                               int month,
                               int dayOfMonth)
        Obtains a local date in Hijrah calendar system from the proleptic-year, month-of-year and day-of-month fields.
        Specified by:
        date in interface Chronology
        Parameters:
        prolepticYear - the proleptic-year
        month - the month-of-year
        dayOfMonth - the day-of-month
        Returns:
        the Hijrah local date, not null
        Throws:
        DateTimeException - if unable to create the date
      • dateYearDay

        public HijrahDate dateYearDay​(Era era,
                                      int yearOfEra,
                                      int dayOfYear)
        Obtains a local date in Hijrah calendar system from the era, year-of-era and day-of-year fields.
        Specified by:
        dateYearDay in interface Chronology
        Parameters:
        era - the Hijrah era, not null
        yearOfEra - the year-of-era
        dayOfYear - the day-of-year
        Returns:
        the Hijrah local date, not null
        Throws:
        DateTimeException - if unable to create the date
        ClassCastException - if the era is not a HijrahEra
      • dateYearDay

        public HijrahDate dateYearDay​(int prolepticYear,
                                      int dayOfYear)
        Obtains a local date in Hijrah calendar system from the proleptic-year and day-of-year fields.
        Specified by:
        dateYearDay in interface Chronology
        Parameters:
        prolepticYear - the proleptic-year
        dayOfYear - the day-of-year
        Returns:
        the Hijrah local date, not null
        Throws:
        DateTimeException - if the value of the year is out of range, or if the day-of-year is invalid for the year
      • dateEpochDay

        public HijrahDate dateEpochDay​(long epochDay)
        Obtains a local date in the Hijrah calendar system from the epoch-day.
        Specified by:
        dateEpochDay in interface Chronology
        Parameters:
        epochDay - the epoch day
        Returns:
        the Hijrah local date, not null
        Throws:
        DateTimeException - if unable to create the date
      • eraOf

        public HijrahEra eraOf​(int eraValue)
        Creates the HijrahEra object from the numeric value. The Hijrah calendar system has only one era covering the proleptic years greater than zero. This method returns the singleton HijrahEra for the value 1.
        Specified by:
        eraOf in interface Chronology
        Parameters:
        eraValue - the era value
        Returns:
        the calendar system era, not null
        Throws:
        DateTimeException - if unable to create the era