Class DiscordianChronology

java.lang.Object
java.time.chrono.AbstractChronology
org.threeten.extra.chrono.DiscordianChronology
All Implemented Interfaces:
Serializable, Comparable<Chronology>, Chronology

public final class DiscordianChronology extends AbstractChronology implements Serializable
The Discordian calendar system.

This chronology defines the rules of the proleptic Discordian calendar system. The Discordian differs from the Gregorian in terms of month and week lengths, with an offset year. Dates are aligned such that each Discordian year starts with each ISO year, with an offset index.

This class is not proleptic. It implements Discordian rules only since YOLD 1 (ISO BCE 1166).

The fields are defined as follows:

  • era - There is one era, the current 'Year of Our Lady of Discord' (YOLD).
  • year-of-era - The year-of-era for the current era increases uniformly from the epoch at year one.
  • proleptic-year - The proleptic year is the same as the year-of-era for the current era.
  • month-of-year - There are 5 months in a Discordian year, numbered from 1 to 5.
  • day-of-week - There are 5 days in a Discordian week, numbered from 1 to 5.
  • day-of-month - There are 73 days in each Discordian month, numbered from 1 to 73.
  • day-of-year - There are 365 days in a standard Discordian year and 366 in a leap year. The days are numbered from 1 to 365 or 1 to 366.
  • leap-year - Leap years occur in sync with ISO leap-years; that is, they occur every 4 ISO years, excepting when that ISO year is divisible by 100 but not 400.
  • St. Tib's Day - St. Tib's Day occurs each leap-year, and is inserted between the 59th and 60th day of the first month. St. Tib's Day is not part of any month, nor is it part of the Discordian week. It is aligned with the ISO calendar leap-day (February 29th).

Implementation Requirements

This class is immutable and thread-safe.
See Also:
  • Field Details

    • INSTANCE

      public static final DiscordianChronology INSTANCE
      Singleton instance for the Discordian chronology.
  • Constructor Details

    • DiscordianChronology

      @Deprecated public DiscordianChronology()
      Deprecated.
      Use the singleton INSTANCE instead.
      Private constructor, that is public to satisfy the ServiceLoader.
  • Method Details

    • getId

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

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

      Specified by:
      getId in interface Chronology
      Returns:
      the chronology ID - 'Discordian'
      See Also:
    • getCalendarType

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

      The Unicode Locale Data Markup Language (LDML) specification does not define an identifier for the Discordian calendar, but were it to do so, 'discordian' is highly likely to be chosen.

      Specified by:
      getCalendarType in interface Chronology
      Returns:
      the calendar system type - 'discordian'
      See Also:
    • date

      public DiscordianDate date(Era era, int yearOfEra, int month, int dayOfMonth)
      Obtains a local date in Discordian 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 Discordian era, not null
      yearOfEra - the year-of-era
      month - the month-of-year
      dayOfMonth - the day-of-month
      Returns:
      the Discordian local date, not null
      Throws:
      DateTimeException - if unable to create the date
      ClassCastException - if the era is not a DiscordianEra
    • date

      public DiscordianDate date(int prolepticYear, int month, int dayOfMonth)
      Obtains a local date in Discordian 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 Discordian local date, not null
      Throws:
      DateTimeException - if unable to create the date
    • dateYearDay

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

      public DiscordianDate dateYearDay(int prolepticYear, int dayOfYear)
      Obtains a local date in the Discordian 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 Discordian local date, not null
      Throws:
      DateTimeException - if unable to create the date
    • dateEpochDay

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

      public DiscordianDate dateNow()
      Obtains the current Discordian local date 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.

      Specified by:
      dateNow in interface Chronology
      Returns:
      the current Discordian local date using the system clock and default time-zone, not null
      Throws:
      DateTimeException - if unable to create the date
    • dateNow

      public DiscordianDate dateNow(ZoneId zone)
      Obtains the current Discordian local date 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.

      Specified by:
      dateNow in interface Chronology
      Parameters:
      zone - the zone ID to use, not null
      Returns:
      the current Discordian local date using the system clock, not null
      Throws:
      DateTimeException - if unable to create the date
    • dateNow

      public DiscordianDate dateNow(Clock clock)
      Obtains the current Discordian local date 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.

      Specified by:
      dateNow in interface Chronology
      Parameters:
      clock - the clock to use, not null
      Returns:
      the current Discordian local date, not null
      Throws:
      DateTimeException - if unable to create the date
    • date

      public DiscordianDate date(TemporalAccessor temporal)
      Obtains a Discordian local date from another date-time object.
      Specified by:
      date in interface Chronology
      Parameters:
      temporal - the date-time object to convert, not null
      Returns:
      the Discordian local date, not null
      Throws:
      DateTimeException - if unable to create the date
    • localDateTime

      public ChronoLocalDateTime<DiscordianDate> localDateTime(TemporalAccessor temporal)
      Obtains a Discordian local date-time from another date-time object.
      Specified by:
      localDateTime in interface Chronology
      Parameters:
      temporal - the date-time object to convert, not null
      Returns:
      the Discordian local date-time, not null
      Throws:
      DateTimeException - if unable to create the date-time
    • zonedDateTime

      public ChronoZonedDateTime<DiscordianDate> zonedDateTime(TemporalAccessor temporal)
      Obtains a Discordian zoned date-time from another date-time object.
      Specified by:
      zonedDateTime in interface Chronology
      Parameters:
      temporal - the date-time object to convert, not null
      Returns:
      the Discordian zoned date-time, not null
      Throws:
      DateTimeException - if unable to create the date-time
    • zonedDateTime

      public ChronoZonedDateTime<DiscordianDate> zonedDateTime(Instant instant, ZoneId zone)
      Obtains a Discordian zoned date-time in this chronology from an Instant.
      Specified by:
      zonedDateTime in interface Chronology
      Parameters:
      instant - the instant to create the date-time from, not null
      zone - the time-zone, not null
      Returns:
      the Discordian zoned date-time, not null
      Throws:
      DateTimeException - if the result exceeds the supported range
    • isLeapYear

      public boolean isLeapYear(long prolepticYear)
      Checks if the specified year is a leap year.

      A Discordian proleptic-year is leap if the remainder after division by four equals zero. There are two special cases. If the year minus 1166 is divisible by 100 it is not a leap year, unless it is also divisible by 400, when it is a leap year. These rules produce leap days on the same dates as the ISO-8601 calendar system.

      Specified by:
      isLeapYear in interface 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)
      Specified by:
      prolepticYear in interface Chronology
    • eraOf

      public DiscordianEra eraOf(int era)
      Specified by:
      eraOf in interface Chronology
    • eras

      public List<Era> eras()
      Specified by:
      eras in interface Chronology
    • range

      public ValueRange range(ChronoField field)
      Specified by:
      range in interface Chronology
    • resolveDate

      public DiscordianDate resolveDate(Map<TemporalField,Long> fieldValues, ResolverStyle resolverStyle)
      Specified by:
      resolveDate in interface Chronology
      Overrides:
      resolveDate in class AbstractChronology