Package org.orekit.time

Class DateComponents

java.lang.Object
org.orekit.time.DateComponents
All Implemented Interfaces:
Serializable, Comparable<DateComponents>
public class DateComponents extends Object implements Serializable, Comparable<DateComponents>
Class representing a date broken up as year, month and day components.

This class uses the astronomical convention for calendars, which is also the convention used by java.util.Date: a year zero is present between years -1 and +1, and 10 days are missing in 1582. The calendar used around these special dates are:

  • up to 0000-12-31 : proleptic julian calendar
  • from 0001-01-01 to 1582-10-04: julian calendar
  • from 1582-10-15: gregorian calendar

Instances of this class are guaranteed to be immutable.

Author:
Luc Maisonobe
See Also:

  • Field Details

    • JULIAN_EPOCH

      public static final DateComponents JULIAN_EPOCH
      Reference epoch for julian dates: -4712-01-01.

      Both java.util.Date and DateComponents classes follow the astronomical conventions and consider a year 0 between years -1 and +1, hence this reference date lies in year -4712 and not in year -4713 as can be seen in other documents or programs that obey a different convention (for example the convcal utility).

    • MODIFIED_JULIAN_EPOCH

      public static final DateComponents MODIFIED_JULIAN_EPOCH
      Reference epoch for modified julian dates: 1858-11-17.

    • FIFTIES_EPOCH

      public static final DateComponents FIFTIES_EPOCH
      Reference epoch for 1950 dates: 1950-01-01.

    • CCSDS_EPOCH

      public static final DateComponents CCSDS_EPOCH
      Reference epoch for CCSDS Time Code Format (CCSDS 301.0-B-4): 1958-01-01.

    • GALILEO_EPOCH

      public static final DateComponents GALILEO_EPOCH
      Reference epoch for Galileo System Time: 1999-08-22.

    • GPS_EPOCH

      public static final DateComponents GPS_EPOCH
      Reference epoch for GPS weeks: 1980-01-06.

    • QZSS_EPOCH

      public static final DateComponents QZSS_EPOCH
      Reference epoch for QZSS weeks: 1980-01-06.

    • BEIDOU_EPOCH

      public static final DateComponents BEIDOU_EPOCH
      Reference epoch for BeiDou weeks: 2006-01-01.

    • GLONASS_EPOCH

      public static final DateComponents GLONASS_EPOCH
      Reference epoch for GLONASS four-year interval number: 1996-01-01.

    • J2000_EPOCH

      public static final DateComponents J2000_EPOCH
      J2000.0 Reference epoch: 2000-01-01.

    • JAVA_EPOCH

      public static final DateComponents JAVA_EPOCH
      Java Reference epoch: 1970-01-01.

    • MAX_EPOCH

      public static final DateComponents MAX_EPOCH
      Maximum supported date.

      This is date 5881610-07-11 which corresponds to Integer.MAX_VALUE days after J2000_EPOCH.

      Since:
      9.0

    • MIN_EPOCH

      public static final DateComponents MIN_EPOCH
      Maximum supported date.

      This is date -5877490-03-03, which corresponds to Integer.MIN_VALUE days before J2000_EPOCH.

      Since:
      9.0

    • JD_TO_MJD

      public static final double JD_TO_MJD
      Offset between julian day epoch and modified julian day epoch.
      See Also:

  • Constructor Details

    • DateComponents

      public DateComponents(int year, int month, int day) throws IllegalArgumentException
      Build a date from its components.
      Parameters:
      year - year number (may be 0 or negative for BC years)
      month - month number from 1 to 12
      day - day number from 1 to 31
      Throws:
      IllegalArgumentException - if inconsistent arguments are given (parameters out of range, february 29 for non-leap years, dates during the gregorian leap in 1582 ...)

    • DateComponents

      public DateComponents(int year, Month month, int day) throws IllegalArgumentException
      Build a date from its components.
      Parameters:
      year - year number (may be 0 or negative for BC years)
      month - month enumerate
      day - day number from 1 to 31
      Throws:
      IllegalArgumentException - if inconsistent arguments are given (parameters out of range, february 29 for non-leap years, dates during the gregorian leap in 1582 ...)

    • DateComponents

      public DateComponents(int year, int dayNumber) throws IllegalArgumentException
      Build a date from a year and day number.
      Parameters:
      year - year number (may be 0 or negative for BC years)
      dayNumber - day number in the year from 1 to 366
      Throws:
      IllegalArgumentException - if dayNumber is out of range with respect to year

    • DateComponents

      public DateComponents(int offset)
      Build a date from its offset with respect to a J2000_EPOCH.
      Parameters:
      offset - offset with respect to a J2000_EPOCH
      See Also:

    • DateComponents

      public DateComponents(DateComponents epoch, int offset)
      Build a date from its offset with respect to a reference epoch.

      This constructor is mainly useful to build a date from a modified julian day (using MODIFIED_JULIAN_EPOCH) or a GPS week number (using GPS_EPOCH).

      Parameters:
      epoch - reference epoch
      offset - offset with respect to a reference epoch
      See Also:

  • Method Details

    • createFromWeekComponents

      public static DateComponents createFromWeekComponents(int wYear, int week, int dayOfWeek) throws IllegalArgumentException
      Build a date from week components.

      The calendar week number is a number between 1 and 52 or 53 depending on the year. Week 1 is defined by ISO as the one that includes the first Thursday of a year. Week 1 may therefore start the previous year and week 52 or 53 may end in the next year. As an example calendar date 1995-01-01 corresponds to week date 1994-W52-7 (i.e. Sunday in the last week of 1994 is in fact the first day of year 1995). This date would beAnother example is calendar date 1996-12-31 which corresponds to week date 1997-W01-2 (i.e. Tuesday in the first week of 1997 is in fact the last day of year 1996).

      Parameters:
      wYear - year associated to week numbering
      week - week number in year, from 1 to 52 or 53
      dayOfWeek - day of week, from 1 (Monday) to 7 (Sunday)
      Returns:
      a builded date
      Throws:
      IllegalArgumentException - if inconsistent arguments are given (parameters out of range, week 53 on a 52 weeks year ...)

    • parseDate

      public static DateComponents parseDate(String string)
      Parse a string in ISO-8601 format to build a date.

      The supported formats are:

      • basic format calendar date: YYYYMMDD
      • extended format calendar date: YYYY-MM-DD
      • basic format ordinal date: YYYYDDD
      • extended format ordinal date: YYYY-DDD
      • basic format week date: YYYYWwwD
      • extended format week date: YYYY-Www-D

      As shown by the list above, only the complete representations defined in section 4.1 of ISO-8601 standard are supported, neither expended representations nor representations with reduced accuracy are supported.

      Parsing a single integer as a julian day is not supported as it may be ambiguous with either the basic format calendar date or the basic format ordinal date depending on the number of digits.

      Parameters:
      string - string to parse
      Returns:
      a parsed date
      Throws:
      IllegalArgumentException - if string cannot be parsed

    • getYear

      public int getYear()
      Get the year number.
      Returns:
      year number (may be 0 or negative for BC years)

    • getMonth

      public int getMonth()
      Get the month.
      Returns:
      month number from 1 to 12

    • getMonthEnum

      public Month getMonthEnum()
      Get the month as an enumerate.
      Returns:
      month as an enumerate

    • getDay

      public int getDay()
      Get the day.
      Returns:
      day number from 1 to 31

    • getJ2000Day

      public int getJ2000Day()
      Get the day number with respect to J2000 epoch.
      Returns:
      day number with respect to J2000 epoch

    • getMJD

      public int getMJD()
      Get the modified julian day.
      Returns:
      modified julian day

    • getCalendarWeek

      public int getCalendarWeek()
      Get the calendar week number.

      The calendar week number is a number between 1 and 52 or 53 depending on the year. Week 1 is defined by ISO as the one that includes the first Thursday of a year. Week 1 may therefore start the previous year and week 52 or 53 may end in the next year. As an example calendar date 1995-01-01 corresponds to week date 1994-W52-7 (i.e. Sunday in the last week of 1994 is in fact the first day of year 1995). Another example is calendar date 1996-12-31 which corresponds to week date 1997-W01-2 (i.e. Tuesday in the first week of 1997 is in fact the last day of year 1996).

      Returns:
      calendar week number

    • getDayOfWeek

      public int getDayOfWeek()
      Get the day of week.

      Day of week is a number between 1 (Monday) and 7 (Sunday).

      Returns:
      day of week

    • getDayOfYear

      public int getDayOfYear()
      Get the day number in year.

      Day number in year is between 1 (January 1st) and either 365 or 366 inclusive depending on year.

      Returns:
      day number in year

    • toString

      public String toString()
      Get a string representation (ISO-8601) of the date.
      Overrides:
      toString in class Object
      Returns:
      string representation of the date.

    • compareTo

      public int compareTo(DateComponents other)
      Specified by:
      compareTo in interface Comparable<DateComponents>

    • equals

      public boolean equals(Object other)
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object