Package net.time4j.engine

Interface CalendarSystem<D>

Type Parameters:
D - generic type of calendar date (subtype of Calendrical or CalendarVariant)
public interface CalendarSystem<D>

Represents a calendar system which can map a calendar date to a day number corresponding to the count of days elapsed since UTC epoch [1972-01-01].

Note: All implementations must be immutable.

Author:
Meno Hochschild
See Also:
Calendrical, CalendarVariant, EpochDays

  • Method Summary

    Modifier and Type
    Method
    Description
    List<CalendarEra>
    getEras()
    Yields an enumeration of valid eras in ascending order.
    long
    getMaximumSinceUTC()
    Gets the maximum day number as count of days since the introduction of UTC [1972-01-01].
    long
    getMinimumSinceUTC()
    Gets the minimum day number as count of days since the introduction of UTC [1972-01-01].
    D
    transform​(long utcDays)
    Transforms given day number to a calendar date on the local time line at the reference time of noon.
    long
    transform​(D date)
    Transforms given calendar date to a day number on the local time line at the reference time of noon.

  • Method Details

    • transform

      D transform​(long utcDays)

      Transforms given day number to a calendar date on the local time line at the reference time of noon.

      Parameters:
      utcDays - count of days since UTC epoch [1972-01-01]
      Returns:
      new calendar date
      Throws:
      IllegalArgumentException - if the argument is out of range

    • transform

      long transform​(D date)

      Transforms given calendar date to a day number on the local time line at the reference time of noon.

      Parameters:
      date - calendar date to be transformed
      Returns:
      count of days since UTC epoch [1972-01-01]
      Throws:
      IllegalArgumentException - if the argument is not consistent with this calendar system

    • getMinimumSinceUTC

      long getMinimumSinceUTC()

      Gets the minimum day number as count of days since the introduction of UTC [1972-01-01].

      Returns:
      smallest count of days relative to UTC epoch [1972-01-01]
      See Also:
      getMaximumSinceUTC()

    • getMaximumSinceUTC

      long getMaximumSinceUTC()

      Gets the maximum day number as count of days since the introduction of UTC [1972-01-01].

      Returns:
      largest count of days relative to UTC epoch [1972-01-01]
      See Also:
      getMinimumSinceUTC()

    • getEras

      List<CalendarEra> getEras()

      Yields an enumeration of valid eras in ascending order.

      All ISO-systems only yield an empty list. A gregorian calendar defines the eras BC and AD related to Jesu birth however.

      Returns:
      unmodifiable list of eras (maybe empty)