Package org.threeten.extra.chrono

Class Symmetry454Chronology

java.lang.Object
java.time.chrono.AbstractChronology
org.threeten.extra.chrono.Symmetry454Chronology
All Implemented Interfaces:
Serializable, Comparable<Chronology>, Chronology
public final class Symmetry454Chronology extends AbstractChronology implements Serializable
The Symmetry454 calendar system.

This chronology defines the rules of the Symmetry454 calendar system. Dates are aligned such that 0001/01/01 (Sym454) is 0001-01-01 (ISO).

The calendar implemented by this class is proleptic, with January 1st as the start of the year. Each month either has 28 days or 35 days, in an alternating pattern; January has 28 days, February has 35 days and March again has 28 days. Due to this, each quarter consists of 13 weeks.

Normal years thus have 364 days, whereas leap years have an extra week, aptly called leap week, added to the end, extending the year to 371 days.

The fields are defined as follows:

  • era - Same eras as used in the Gregorian calendar: 'Before Common Era' (BCE) and 'Common Era' (CE).
  • year-of-era - The year-of-era for the current era increases uniformly from the epoch at year 1.
  • proleptic-year - The proleptic year is the same as the year-of-era for the current era.
  • month-of-year - There are 12 months in an Symmetry454 year, numbered from 1 to 12.
  • day-of-month - There are 28 days in a standard Symmetry454 month, numbered from 1 to 28, except for the middle-month in each quarter, which spans 35 days: February, May, August, November; and December in leap years.
  • day-of-year - There are 364 days in a standard Symmetry454 year and 371 days in a leap year. The days are numbered accordingly.
  • leap-year - Leap years occur every 5 or 6 years, evenly spread over 293 years according the formula: (52 > ((52 * year + 146) % 293)).
  • Week day - every month starts on a Monday. There are no days outside of the week or month.

Implementation Requirements

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

  • Field Details

    • INSTANCE

      public static final Symmetry454Chronology INSTANCE
      Singleton instance for the Symmetry454 chronology.

    • DAYS_0001_TO_1970

      public static final long DAYS_0001_TO_1970
      The number of days from year zero to CE 1970, still the era only allows CE 1 and higher. There are 6 full 293-year cycles from CE 1 to 1758, with 6 * 52 leap years, i.e. 312. There are 37 leap years from CE 1758 to 1970.
      See Also:

  • Constructor Details

    • Symmetry454Chronology

      @Deprecated public Symmetry454Chronology()
      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 - 'Sym454'.

      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 - 'Sym454'
      See Also:

    • getCalendarType

      public String getCalendarType()
      Gets the calendar type of the underlying calendar system, which returns null.

      The Unicode Locale Data Markup Language (LDML) specification does not define an identifier for this calendar system, thus null is returned.

      Specified by:
      getCalendarType in interface Chronology
      Returns:
      the calendar system type, null
      See Also:

    • date

      public Symmetry454Date date(Era era, int yearOfEra, int month, int dayOfMonth)
      Obtains a local date in Symmetry454 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 Symmetry454 era, not null
      yearOfEra - the year-of-era
      month - the month-of-year
      dayOfMonth - the day-of-month
      Returns:
      the Symmetry454 local date, not null
      Throws:
      DateTimeException - if unable to create the date
      ClassCastException - if the era is not a IsoEra

    • date

      public Symmetry454Date date(int prolepticYear, int month, int dayOfMonth)
      Obtains a local date in Symmetry454 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 Symmetry454 local date, not null
      Throws:
      DateTimeException - if unable to create the date

    • dateYearDay

      public Symmetry454Date dateYearDay(Era era, int yearOfEra, int dayOfYear)
      Obtains a local date in Symmetry454 calendar system from the era, year-of-era and day-of-year fields.
      Specified by:
      dateYearDay in interface Chronology
      Parameters:
      era - the Symmetry454 era, not null
      yearOfEra - the year-of-era
      dayOfYear - the day-of-year
      Returns:
      the Symmetry454 local date, not null
      Throws:
      DateTimeException - if unable to create the date
      ClassCastException - if the era is not a IsoEra

    • dateYearDay

      public Symmetry454Date dateYearDay(int prolepticYear, int dayOfYear)
      Obtains a local date in Symmetry454 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 Symmetry454 local date, not null
      Throws:
      DateTimeException - if unable to create the date

    • dateEpochDay

      public Symmetry454Date dateEpochDay(long epochDay)
      Obtains a local date in the Symmetry454 calendar system from the epoch-day.
      Specified by:
      dateEpochDay in interface Chronology
      Parameters:
      epochDay - the epoch day
      Returns:
      the Symmetry454 local date, not null
      Throws:
      DateTimeException - if unable to create the date

    • dateNow

      public Symmetry454Date dateNow()
      Obtains the current Symmetry454 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 Symmetry454 local date using the system clock and default time-zone, not null
      Throws:
      DateTimeException - if unable to create the date

    • dateNow

      public Symmetry454Date dateNow(ZoneId zone)
      Obtains the current Symmetry454 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 Symmetry454 local date using the system clock, not null
      Throws:
      DateTimeException - if unable to create the date

    • dateNow

      public Symmetry454Date dateNow(Clock clock)
      Obtains the current Symmetry454 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 Symmetry454 local date, not null
      Throws:
      DateTimeException - if unable to create the date

    • date

      public Symmetry454Date date(TemporalAccessor temporal)
      Obtains a Symmetry454 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 Symmetry454 local date, not null
      Throws:
      DateTimeException - if unable to create the date

    • localDateTime

      public ChronoLocalDateTime<Symmetry454Date> localDateTime(TemporalAccessor temporal)
      Obtains a Symmetry454 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 Symmetry454 local date-time, not null
      Throws:
      DateTimeException - if unable to create the date-time

    • zonedDateTime

      public ChronoZonedDateTime<Symmetry454Date> zonedDateTime(TemporalAccessor temporal)
      Obtains a Symmetry454 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 Symmetry454 zoned date-time, not null
      Throws:
      DateTimeException - if unable to create the date-time

    • zonedDateTime

      public ChronoZonedDateTime<Symmetry454Date> zonedDateTime(Instant instant, ZoneId zone)
      Obtains a Symmetry454 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 Symmetry454 zoned date-time, not null
      Throws:
      DateTimeException - if the result exceeds the supported range

    • isLeapYear

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

      A leap-year is a year of a longer length than normal. Leap years in the calendar system match those of the ISO calendar system.

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

    • eraOf

      public IsoEra eraOf(int eraValue)
      Creates the chronology era object from the numeric value.

      The list of eras is shared with IsoEra.

      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

    • eras

      public List<Era> eras()
      Gets the list of eras for the chronology.

      The list of eras is shared with IsoEra.

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

    • range

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

    • prolepticYear

      public int prolepticYear(Era era, int yearOfEra)
      Specified by:
      prolepticYear in interface Chronology

    • getLeapYearsBefore

      public static long getLeapYearsBefore(long prolepticYear)
      Get the count of leap years since CE 1.
      Parameters:
      prolepticYear - the year
      Returns:
      the number of leap years since CE 1