Package org.threeten.bp.chrono

Class HijrahChronology

  • All Implemented Interfaces:
    Serializable, Comparable<Chronology>
    public final class HijrahChronology
extends Chronology
implements Serializable
    The Hijrah calendar system.

    This chronology defines the rules of the Hijrah calendar system.

    The implementation follows the Freeman-Grenville algorithm (*1) and has following features.

    • A year has 12 months.
    • Over a cycle of 30 years there are 11 leap years.
    • There are 30 days in month number 1, 3, 5, 7, 9, and 11, and 29 days in month number 2, 4, 6, 8, 10, and 12.
    • In a leap year month 12 has 30 days.
    • In a 30 year cycle, year 2, 5, 7, 10, 13, 16, 18, 21, 24, 26, and 29 are leap years.
    • Total of 10631 days in a 30 years cycle.

    The table shows the features described above.

    # of month Name of month Number of days
    1 Muharram 30
    2 Safar 29
    3 Rabi'al-Awwal 30
    4 Rabi'ath-Thani 29
    5 Jumada l-Ula 30
    6 Jumada t-Tania 29
    7 Rajab 30
    8 Sha`ban 29
    9 Ramadan 30
    10 Shawwal 29
    11 Dhu 'l-Qa`da 30
    12 Dhu 'l-Hijja 29, but 30 days in years 2, 5, 7, 10,
    13, 16, 18, 21, 24, 26, and 29

    (*1) The algorithm is taken from the book, The Muslim and Christian Calendars by G.S.P. Freeman-Grenville.

    Specification for implementors

    This class is immutable and thread-safe.
    See Also:
    Serialized Form

    • Field Detail

      • INSTANCE

        public static final HijrahChronology INSTANCE
        Singleton instance of the Hijrah chronology.

    • Method Detail

      • getId

        public String getId()
        Gets the ID of the chronology - 'Hijrah-umalqura'.

        The ID uniquely identifies the Chronology. It can be used to lookup the Chronology using Chronology.of(String).

        Specified by:
        getId in class Chronology
        Returns:
        the chronology ID - 'Hijrah-umalqura'
        See Also:
        getCalendarType()

      • getCalendarType

        public String getCalendarType()
        Gets the calendar type of the underlying calendar system - 'islamic-umalqura'.

        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). It can also be used as part of a locale, accessible via Locale#getUnicodeLocaleType(String) with the key 'ca'.

        Specified by:
        getCalendarType in class Chronology
        Returns:
        the calendar system type - 'islamic-umalqura'
        See Also:
        getId()

      • date

        public HijrahDate date​(Era era,
                       int yearOfEra,
                       int month,
                       int dayOfMonth)
        Description copied from class: Chronology
        Obtains a local date in this chronology from the era, year-of-era, month-of-year and day-of-month fields.
        Overrides:
        date in class Chronology
        Parameters:
        era - the era of the correct type for the chronology, not null
        yearOfEra - the chronology year-of-era
        month - the chronology month-of-year
        dayOfMonth - the chronology day-of-month
        Returns:
        the local date in this chronology, not null

      • date

        public HijrahDate date​(int prolepticYear,
                       int month,
                       int dayOfMonth)
        Description copied from class: Chronology
        Obtains a local date in this chronology from the proleptic-year, month-of-year and day-of-month fields.
        Specified by:
        date in class Chronology
        Parameters:
        prolepticYear - the chronology proleptic-year
        month - the chronology month-of-year
        dayOfMonth - the chronology day-of-month
        Returns:
        the local date in this chronology, not null

      • dateYearDay

        public HijrahDate dateYearDay​(Era era,
                              int yearOfEra,
                              int dayOfYear)
        Description copied from class: Chronology
        Obtains a local date in this chronology from the era, year-of-era and day-of-year fields.
        Overrides:
        dateYearDay in class Chronology
        Parameters:
        era - the era of the correct type for the chronology, not null
        yearOfEra - the chronology year-of-era
        dayOfYear - the chronology day-of-year
        Returns:
        the local date in this chronology, not null

      • dateYearDay

        public HijrahDate dateYearDay​(int prolepticYear,
                              int dayOfYear)
        Description copied from class: Chronology
        Obtains a local date in this chronology from the proleptic-year and day-of-year fields.
        Specified by:
        dateYearDay in class Chronology
        Parameters:
        prolepticYear - the chronology proleptic-year
        dayOfYear - the chronology day-of-year
        Returns:
        the local date in this chronology, not null

      • dateEpochDay

        public HijrahDate dateEpochDay​(long epochDay)
        Description copied from class: Chronology
        Obtains a local date in this chronology from the epoch-day.

        The definition of EPOCH_DAY is the same for all calendar systems, thus it can be used for conversion.

        Specified by:
        dateEpochDay in class Chronology
        Parameters:
        epochDay - the epoch day
        Returns:
        the local date in this chronology, not null

      • date

        public HijrahDate date​(TemporalAccessor temporal)
        Description copied from class: Chronology
        Obtains a local date in this chronology from another temporal object.

        This creates a date in this chronology based on the specified TemporalAccessor.

        The standard mechanism for conversion between date types is the local epoch-day field.

        Specified by:
        date in class Chronology
        Parameters:
        temporal - the temporal object to convert, not null
        Returns:
        the local date in this chronology, not null

      • localDateTime

        public ChronoLocalDateTime<HijrahDate> localDateTime​(TemporalAccessor temporal)
        Description copied from class: Chronology
        Obtains a local date-time in this chronology from another temporal object.

        This creates a date-time in this chronology based on the specified TemporalAccessor.

        The date of the date-time should be equivalent to that obtained by calling Chronology.date(TemporalAccessor). The standard mechanism for conversion between time types is the nano-of-day field.

        Overrides:
        localDateTime in class Chronology
        Parameters:
        temporal - the temporal object to convert, not null
        Returns:
        the local date-time in this chronology, not null

      • zonedDateTime

        public ChronoZonedDateTime<HijrahDate> zonedDateTime​(TemporalAccessor temporal)
        Description copied from class: Chronology
        Obtains a zoned date-time in this chronology from another temporal object.

        This creates a date-time in this chronology based on the specified TemporalAccessor.

        This should obtain a ZoneId using ZoneId.from(TemporalAccessor). The date-time should be obtained by obtaining an Instant. If that fails, the local date-time should be used.

        Overrides:
        zonedDateTime in class Chronology
        Parameters:
        temporal - the temporal object to convert, not null
        Returns:
        the zoned date-time in this chronology, not null

      • zonedDateTime

        public ChronoZonedDateTime<HijrahDate> zonedDateTime​(Instant instant,
                                                     ZoneId zone)
        Description copied from class: Chronology
        Obtains a zoned date-time in this chronology from an Instant.

        This creates a zoned date-time with the same instant as that specified.

        Overrides:
        zonedDateTime in class Chronology
        Parameters:
        instant - the instant to create the date-time from, not null
        zone - the time-zone, not null
        Returns:
        the zoned date-time, not null

      • dateNow

        public HijrahDate dateNow()
        Description copied from class: Chronology
        Obtains the current local date in this chronology from the system clock in the default time-zone.

        This will query the system clock in the default time-zone to obtain the current date.

        Using this method will prevent the ability to use an alternate clock for testing because the clock is hard-coded.

        This implementation uses Chronology.dateNow(Clock).

        Overrides:
        dateNow in class Chronology
        Returns:
        the current local date using the system clock and default time-zone, not null

      • dateNow

        public HijrahDate dateNow​(ZoneId zone)
        Description copied from class: Chronology
        Obtains the current local date in this chronology from the system clock in the specified time-zone.

        This will query the system clock to obtain the current date. Specifying the time-zone avoids dependence on the default time-zone.

        Using this method will prevent the ability to use an alternate clock for testing because the clock is hard-coded.

        Overrides:
        dateNow in class Chronology
        Parameters:
        zone - the zone ID to use, not null
        Returns:
        the current local date using the system clock, not null

      • dateNow

        public HijrahDate dateNow​(Clock clock)
        Description copied from class: Chronology
        Obtains the current local date in this chronology from the specified clock.

        This will query the specified clock to obtain the current date - today. Using this method allows the use of an alternate clock for testing. The alternate clock may be introduced using dependency injection.

        Overrides:
        dateNow in class Chronology
        Parameters:
        clock - the clock to use, not null
        Returns:
        the current local date, not null

      • isLeapYear

        public boolean isLeapYear​(long prolepticYear)
        Description copied from class: Chronology
        Checks if the specified year is a leap year.

        A leap-year is a year of a longer length than normal. The exact meaning is determined by the chronology according to the following constraints.

        • a leap-year must imply a year-length longer than a non leap-year.
        • a chronology that does not support the concept of a year must return false.

        Specified by:
        isLeapYear in class Chronology
        Parameters:
        prolepticYear - the proleptic-year to check, not validated for range
        Returns:
        true if the year is a leap year

      • prolepticYear

        public int prolepticYear​(Era era,
                         int yearOfEra)
        Description copied from class: Chronology
        Calculates the proleptic-year given the era and year-of-era.

        This combines the era and year-of-era into the single proleptic-year field.

        Specified by:
        prolepticYear in class Chronology
        Parameters:
        era - the era of the correct type for the chronology, not null
        yearOfEra - the chronology year-of-era
        Returns:
        the proleptic-year

      • eraOf

        public HijrahEra eraOf​(int eraValue)
        Description copied from class: Chronology
        Creates the chronology era object from the numeric value.

        The era is, conceptually, the largest division of the time-line. Most calendar systems have a single epoch dividing the time-line into two eras. However, some have multiple eras, such as one for the reign of each leader. The exact meaning is determined by the chronology according to the following constraints.

        The era in use at 1970-01-01 must have the value 1. Later eras must have sequentially higher values. Earlier eras must have sequentially lower values. Each chronology must refer to an enum or similar singleton to provide the era values.

        This method returns the singleton era of the correct type for the specified era value.

        Specified by:
        eraOf in class Chronology
        Parameters:
        eraValue - the era value
        Returns:
        the calendar system era, not null

      • eras

        public List<Era> eras()
        Description copied from class: Chronology
        Gets the list of eras for the chronology.

        Most calendar systems have an era, within which the year has meaning. If the calendar system does not support the concept of eras, an empty list must be returned.

        Specified by:
        eras in class Chronology
        Returns:
        the list of eras for the chronology, may be immutable, not null

      • range

        public ValueRange range​(ChronoField field)
        Description copied from class: Chronology
        Gets the range of valid values for the specified field.

        All fields can be expressed as a long integer. This method returns an object that describes the valid range for that value.

        Note that the result only describes the minimum and maximum valid values and it is important not to read too much into them. For example, there could be values within the range that are invalid for the field.

        This method will return a result whether or not the chronology supports the field.

        Specified by:
        range in class Chronology
        Parameters:
        field - the field to get the range for, not null
        Returns:
        the range of valid values for the field, not null

      • resolveDate

        public HijrahDate resolveDate​(Map<TemporalField,​Long> fieldValues,
                              ResolverStyle resolverStyle)
        Description copied from class: Chronology
        Resolves parsed ChronoField values into a date during parsing.

        Most TemporalField implementations are resolved using the resolve method on the field. By contrast, the ChronoField class defines fields that only have meaning relative to the chronology. As such, ChronoField date fields are resolved here in the context of a specific chronology.

        The default implementation, which explains typical resolve behaviour, is provided in AbstractChronology.

        Specified by:
        resolveDate in class Chronology
        Parameters:
        fieldValues - the map of fields to values, which can be updated, not null
        resolverStyle - the requested type of resolve, not null
        Returns:
        the resolved date, null if insufficient information to create a date