Class InternationalFixedDate

java.lang.Object
org.threeten.extra.chrono.InternationalFixedDate
All Implemented Interfaces:
Serializable, Comparable<ChronoLocalDate>, ChronoLocalDate, Temporal, TemporalAccessor, TemporalAdjuster

public final class InternationalFixedDate extends Object implements ChronoLocalDate, Serializable
A date in the International fixed calendar system.

Implements a pure International Fixed calendar (also known as the Cotsworth plan, the Eastman plan, the 13 Month calendar or the Equal Month calendar) a solar calendar proposal for calendar reform designed by Moses B. Cotsworth, who presented it in 1902.

It provides for a year of 13 months of 28 days each. Month 6 has 29 days in a leap year, but the additional day is not part of any week. Month 12 always has 29 days, but the additional day is not part of any week. It is therefore a perennial calendar, with every date fixed always on the same weekday. Though it was never officially adopted in any country, it was the official calendar of the Eastman Kodak Company from 1928 to 1989.

This date operates using the International fixed calendar. This calendar system is a proposed reform calendar system, and is not in common use. The International fixed differs from the Gregorian in terms of month count and length, and the leap year rule. Dates are aligned such that 0001/01/01 (International fixed) is 0001-01-01 (ISO).

More information is available in the International Fixed Calendar Wikipedia article.

Implementation Requirements

This class is immutable and thread-safe.

This class must be treated as a value type. Do not synchronize, rely on the identity hash code or use the distinction between equals() and ==.

See Also:
  • Method Details

    • now

      public static InternationalFixedDate now()
      Obtains the current InternationalFixedDate 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.

      Returns:
      the current date using the system clock and default time-zone, not null
    • now

      public static InternationalFixedDate now(ZoneId zone)
      Obtains the current InternationalFixedDate 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.

      Parameters:
      zone - the zone ID to use, not null
      Returns:
      the current date using the system clock, not null
    • now

      public static InternationalFixedDate now(Clock clock)
      Obtains the current InternationalFixedDate 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.

      Parameters:
      clock - the clock to use, not null
      Returns:
      the current date, not null
      Throws:
      DateTimeException - if the current date cannot be obtained
    • of

      public static InternationalFixedDate of(int prolepticYear, int month, int dayOfMonth)
      Obtains a InternationalFixedDate representing a date in the International fixed calendar system from the proleptic-year, month-of-year and day-of-month fields.

      This returns a InternationalFixedDate with the specified fields. The day must be valid for the year and month, otherwise an exception will be thrown.

      Parameters:
      prolepticYear - the International fixed proleptic-year
      month - the International fixed month-of-year, from 1 to 13
      dayOfMonth - the International fixed day-of-month, from 1 to 28 (29 for Leap Day or Year Day)
      Returns:
      the date in International fixed calendar system, not null
      Throws:
      DateTimeException - if the value of any field is out of range, or if the day-of-month is invalid for the month-year
    • from

      public static InternationalFixedDate from(TemporalAccessor temporal)
      Obtains a InternationalFixedDate from a temporal object.

      This obtains a date in the International fixed calendar system based on the specified temporal. A TemporalAccessor represents an arbitrary set of date and time information, which this factory converts to an instance of InternationalFixedDate.

      The conversion typically uses the EPOCH_DAY field, which is standardized across calendar systems.

      This method matches the signature of the functional interface TemporalQuery allowing it to be used as a query via method reference, InternationalFixedDate::from.

      Parameters:
      temporal - the temporal object to convert, not null
      Returns:
      the date in the International fixed calendar system, not null
      Throws:
      DateTimeException - if unable to convert to a InternationalFixedDate
    • range

      public ValueRange range(TemporalField field)
      Specified by:
      range in interface TemporalAccessor
    • getChronology

      public InternationalFixedChronology getChronology()
      Gets the chronology of this date, which is the International fixed calendar system.

      The Chronology represents the calendar system in use. The era and other fields in ChronoField are defined by the chronology.

      Specified by:
      getChronology in interface ChronoLocalDate
      Returns:
      the International fixed chronology, not null
    • getEra

      public InternationalFixedEra getEra()
      Gets the era applicable at this date.

      The International fixed calendar system only has one era, 'CE', defined by InternationalFixedEra.

      Specified by:
      getEra in interface ChronoLocalDate
      Returns:
      the era applicable at this date, not null
    • lengthOfMonth

      public int lengthOfMonth()
      Returns the length of the month represented by this date.

      This returns the length of the month in days. Month lengths do not match those of the ISO calendar system.

      Months have 28 days, except June which has 29 in leap years and December (month 13) which always has 29 days.

      Specified by:
      lengthOfMonth in interface ChronoLocalDate
      Returns:
      the length of the month in days
    • lengthOfYear

      public int lengthOfYear()
      Returns the length of the year represented by this date.

      This returns the length of the year in days. Year lengths match those of the ISO calendar system.

      Specified by:
      lengthOfYear in interface ChronoLocalDate
      Returns:
      the length of the year in days: 365 or 366
    • with

      public InternationalFixedDate with(TemporalAdjuster adjuster)
      Specified by:
      with in interface ChronoLocalDate
      Specified by:
      with in interface Temporal
    • with

      public InternationalFixedDate with(TemporalField field, long newValue)
      Specified by:
      with in interface ChronoLocalDate
      Specified by:
      with in interface Temporal
    • plus

      public InternationalFixedDate plus(TemporalAmount amount)
      Specified by:
      plus in interface ChronoLocalDate
      Specified by:
      plus in interface Temporal
    • plus

      public InternationalFixedDate plus(long amountToAdd, TemporalUnit unit)
      Specified by:
      plus in interface ChronoLocalDate
      Specified by:
      plus in interface Temporal
    • minus

      public InternationalFixedDate minus(TemporalAmount amount)
      Specified by:
      minus in interface ChronoLocalDate
      Specified by:
      minus in interface Temporal
    • minus

      public InternationalFixedDate minus(long amountToSubtract, TemporalUnit unit)
      Specified by:
      minus in interface ChronoLocalDate
      Specified by:
      minus in interface Temporal
    • atTime

      Specified by:
      atTime in interface ChronoLocalDate
    • until

      public long until(Temporal endExclusive, TemporalUnit unit)
      Specified by:
      until in interface ChronoLocalDate
      Specified by:
      until in interface Temporal
    • until

      public ChronoPeriod until(ChronoLocalDate endDateExclusive)
      Specified by:
      until in interface ChronoLocalDate
    • toEpochDay

      public long toEpochDay()
      Specified by:
      toEpochDay in interface ChronoLocalDate
    • toString

      public String toString()
      Display the date in human-readable format.
      Specified by:
      toString in interface ChronoLocalDate
      Returns:
      the string representation
    • getLong

      public long getLong(TemporalField field)
      Specified by:
      getLong in interface TemporalAccessor
    • equals

      public boolean equals(Object obj)
      Compares this date to another date, including the chronology.

      Compares this date with another ensuring that the date is the same.

      Only objects of this concrete type are compared, other types return false. To compare the dates of two TemporalAccessor instances, including dates in two different chronologies, use ChronoField.EPOCH_DAY as a comparator.

      Specified by:
      equals in interface ChronoLocalDate
      Overrides:
      equals in class Object
      Parameters:
      obj - the object to check, null returns false
      Returns:
      true if this is equal to the other date
    • hashCode

      public int hashCode()
      A hash code for this date.
      Specified by:
      hashCode in interface ChronoLocalDate
      Overrides:
      hashCode in class Object
      Returns:
      a suitable hash code based only on the Chronology and the date