1. Description
2. Field Summary
3. Method Summary
4. Field Details
   1. JULIAN_DAY
   2. MODIFIED_JULIAN_DAY
   3. RATA_DIE

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  static final TemporalField

  JULIAN_DAY

  Julian Day field.

  static final TemporalField

  MODIFIED_JULIAN_DAY

  Modified Julian Day field.

  static final TemporalField

  RATA_DIE

  Rata Die field.

• Method Summary

  Methods declared in class Object

  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  boolean

  equals(Object obj)

  Indicates whether some other object is "equal to" this one.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  int

  hashCode()

  Returns a hash code value for this object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  String

  toString()

  Returns a string representation of the object.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

• Field Details

  • JULIAN_DAY

    public static final TemporalField JULIAN_DAY

    Julian Day field.

    This is an integer-based version of the Julian Day Number. Julian Day is a well-known system that represents the count of whole days since day 0, which is defined to be January 1, 4713 BCE in the Julian calendar, and -4713-11-24 Gregorian. The field has "JulianDay" as 'name', and 'DAYS' as 'baseUnit'. The field always refers to the local date-time, ignoring the offset or zone.

    For date-times, 'JULIAN_DAY.getFrom()' assumes the same value from midnight until just before the next midnight. When 'JULIAN_DAY.adjustInto()' is applied to a date-time, the time of day portion remains unaltered. 'JULIAN_DAY.adjustInto()' and 'JULIAN_DAY.getFrom()' only apply to Temporal objects that can be converted into ChronoField.EPOCH_DAY. An UnsupportedTemporalTypeException is thrown for any other type of object.

    In the resolving phase of parsing, a date can be created from a Julian Day field. In strict mode and smart mode the Julian Day value is validated against the range of valid values. In lenient mode no validation occurs.

    Astronomical and Scientific Notes

    The standard astronomical definition uses a fraction to indicate the time-of-day, where each day is counted from midday to midday. For example, a fraction of 0 represents midday, a fraction of 0.25 represents 18:00, a fraction of 0.5 represents midnight and a fraction of 0.75 represents 06:00.

    By contrast, this implementation has no fractional part, and counts days from midnight to midnight. This implementation uses an integer and days starting at midnight. The integer value for the Julian Day Number is the astronomical Julian Day value at midday of the date in question. This amounts to the astronomical Julian Day, rounded to an integer JDN = floor(JD + 0.5). | ISO date | Julian Day Number | Astronomical Julian Day | | 1970-01-01T00:00 | 2,440,588 | 2,440,587.5 | | 1970-01-01T06:00 | 2,440,588 | 2,440,587.75 | | 1970-01-01T12:00 | 2,440,588 | 2,440,588.0 | | 1970-01-01T18:00 | 2,440,588 | 2,440,588.25 | | 1970-01-02T00:00 | 2,440,589 | 2,440,588.5 | | 1970-01-02T06:00 | 2,440,589 | 2,440,588.75 | | 1970-01-02T12:00 | 2,440,589 | 2,440,589.0 |

    Julian Days are sometimes taken to imply Universal Time or UTC, but this implementation always uses the Julian Day number for the local date, regardless of the offset or time-zone.

  • MODIFIED_JULIAN_DAY

    public static final TemporalField MODIFIED_JULIAN_DAY

    Modified Julian Day field.

    This is an integer-based version of the Modified Julian Day Number. Modified Julian Day (MJD) is a well-known system that counts days continuously. It is defined relative to astronomical Julian Day as MJD = JD - 2400000.5. Each Modified Julian Day runs from midnight to midnight. The field always refers to the local date-time, ignoring the offset or zone.

    For date-times, 'MODIFIED_JULIAN_DAY.getFrom()' assumes the same value from midnight until just before the next midnight. When 'MODIFIED_JULIAN_DAY.adjustInto()' is applied to a date-time, the time of day portion remains unaltered. 'MODIFIED_JULIAN_DAY.adjustInto()' and 'MODIFIED_JULIAN_DAY.getFrom()' only apply to Temporal objects that can be converted into ChronoField.EPOCH_DAY. An UnsupportedTemporalTypeException is thrown for any other type of object.

    This implementation is an integer version of MJD with the decimal part rounded to floor.

    In the resolving phase of parsing, a date can be created from a Modified Julian Day field. In strict mode and smart mode the Modified Julian Day value is validated against the range of valid values. In lenient mode no validation occurs.

    Astronomical and Scientific Notes

    | ISO date | Modified Julian Day | Decimal MJD | | 1970-01-01T00:00 | 40,587 | 40,587.0 | | 1970-01-01T06:00 | 40,587 | 40,587.25 | | 1970-01-01T12:00 | 40,587 | 40,587.5 | | 1970-01-01T18:00 | 40,587 | 40,587.75 | | 1970-01-02T00:00 | 40,588 | 40,588.0 | | 1970-01-02T06:00 | 40,588 | 40,588.25 | | 1970-01-02T12:00 | 40,588 | 40,588.5 | Modified Julian Days are sometimes taken to imply Universal Time or UTC, but this implementation always uses the Modified Julian Day for the local date, regardless of the offset or time-zone.

  • RATA_DIE

    public static final TemporalField RATA_DIE

    Rata Die field.

    Rata Die counts whole days continuously starting day 1 at midnight at the beginning of 0001-01-01 (ISO). The field always refers to the local date-time, ignoring the offset or zone.

    For date-times, 'RATA_DIE.getFrom()' assumes the same value from midnight until just before the next midnight. When 'RATA_DIE.adjustInto()' is applied to a date-time, the time of day portion remains unaltered. 'RATA_DIE.adjustInto()' and 'RATA_DIE.getFrom()' only apply to Temporal objects that can be converted into ChronoField.EPOCH_DAY. An UnsupportedTemporalTypeException is thrown for any other type of object.

    In the resolving phase of parsing, a date can be created from a Rata Die field. In strict mode and smart mode the Rata Die value is validated against the range of valid values. In lenient mode no validation occurs.

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