Class DateUtils


  • public final class DateUtils
    extends java.lang.Object
    Helper methods to deal with date/time formatting with a specific defined format (ISO8601) or a correct pluralization of elapsed time in minutes and seconds.
    Since:
    Ant 1.5
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.text.DateFormat DATE_HEADER_FORMAT
      Deprecated.
      DateFormat is not thread safe, and we cannot guarantee that some other code is using the format in parallel.
      static java.lang.ThreadLocal<java.text.DateFormat> EN_US_DATE_FORMAT_MIN
      Provides a thread-local US-style date format.
      static java.lang.ThreadLocal<java.text.DateFormat> EN_US_DATE_FORMAT_SEC
      Provides a thread-local US-style date format.
      static java.lang.String ISO8601_DATE_PATTERN
      ISO8601-like pattern for date.
      static java.lang.String ISO8601_DATETIME_PATTERN
      ISO8601-like pattern for date-time.
      static java.lang.String ISO8601_TIME_PATTERN
      ISO8601-like pattern for time.
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static java.lang.String format​(long date, java.lang.String pattern)
      Format a date/time into a specific pattern.
      static java.lang.String format​(java.util.Date date, java.lang.String pattern)
      Format a date/time into a specific pattern.
      static java.lang.String formatElapsedTime​(long millis)
      Format an elapsed time into a pluralization correct string.
      static java.lang.String getDateForHeader()
      Returns the current Date in a format suitable for a SMTP date header.
      static int getPhaseOfMoon​(java.util.Calendar cal)
      Calculate the phase of the moon for a given date.
      static java.util.Date parseDateFromHeader​(java.lang.String datestr)
      Parses the string in a format suitable for a SMTP date header.
      static java.util.Date parseIso8601Date​(java.lang.String datestr)
      Parse a string as a date using the ISO8601_DATE format which is yyyy-MM-dd
      static java.util.Date parseIso8601DateTime​(java.lang.String datestr)
      Parse a string as a datetime using the ISO8601_DATETIME format which is yyyy-MM-dd'T'HH:mm:ss
      static java.util.Date parseIso8601DateTimeOrDate​(java.lang.String datestr)
      Parse a string as a date using the either the ISO8601_DATETIME or ISO8601_DATE formats.
      static java.util.Date parseLenientDateTime​(java.lang.String dateStr)
      Parse a lenient ISO 8601, ms since epoch, or <touch>-style date.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • ISO8601_DATETIME_PATTERN

        public static final java.lang.String ISO8601_DATETIME_PATTERN
        ISO8601-like pattern for date-time. It does not support timezone. yyyy-MM-ddTHH:mm:ss
        See Also:
        Constant Field Values
      • ISO8601_DATE_PATTERN

        public static final java.lang.String ISO8601_DATE_PATTERN
        ISO8601-like pattern for date. yyyy-MM-dd
        See Also:
        Constant Field Values
      • ISO8601_TIME_PATTERN

        public static final java.lang.String ISO8601_TIME_PATTERN
        ISO8601-like pattern for time. HH:mm:ss
        See Also:
        Constant Field Values
      • DATE_HEADER_FORMAT

        @Deprecated
        public static final java.text.DateFormat DATE_HEADER_FORMAT
        Deprecated.
        DateFormat is not thread safe, and we cannot guarantee that some other code is using the format in parallel. Deprecated since ant 1.8
        Format used for SMTP (and probably other) Date headers.
      • EN_US_DATE_FORMAT_MIN

        public static final java.lang.ThreadLocal<java.text.DateFormat> EN_US_DATE_FORMAT_MIN
        Provides a thread-local US-style date format. Exactly as used by <touch>, to minute precision: SimpleDateFormat("MM/dd/yyyy hh:mm a", Locale.US)
        Since:
        Ant 1.10.2
      • EN_US_DATE_FORMAT_SEC

        public static final java.lang.ThreadLocal<java.text.DateFormat> EN_US_DATE_FORMAT_SEC
        Provides a thread-local US-style date format. Exactly as used by <touch>, to second precision: SimpleDateFormat("MM/dd/yyyy hh:mm:ss a", Locale.US)
        Since:
        Ant 1.10.2
    • Method Detail

      • format

        public static java.lang.String format​(long date,
                                              java.lang.String pattern)
        Format a date/time into a specific pattern.
        Parameters:
        date - the date to format expressed in milliseconds.
        pattern - the pattern to use to format the date.
        Returns:
        the formatted date.
      • format

        public static java.lang.String format​(java.util.Date date,
                                              java.lang.String pattern)
        Format a date/time into a specific pattern.
        Parameters:
        date - the date to format expressed in milliseconds.
        pattern - the pattern to use to format the date.
        Returns:
        the formatted date.
      • formatElapsedTime

        public static java.lang.String formatElapsedTime​(long millis)
        Format an elapsed time into a pluralization correct string. It is limited only to report elapsed time in minutes and seconds and has the following behavior.
        • minutes are not displayed when 0. (ie: "45 seconds")
        • seconds are always displayed in plural form (ie "0 seconds" or "10 seconds") except for 1 (ie "1 second")
        Parameters:
        millis - the elapsed time to report in milliseconds.
        Returns:
        the formatted text in minutes/seconds.
      • getPhaseOfMoon

        public static int getPhaseOfMoon​(java.util.Calendar cal)
        Calculate the phase of the moon for a given date.

        Code heavily influenced by hacklib.c in Nethack

        The Algorithm:

         moon period = 29.53058 days ~= 30, year = 365.2422 days
        
         days moon phase advances on first day of year compared to preceding year
          = 365.2422 - 12 * 29.53058 ~= 11
        
         years in Metonic cycle (time until same phases fall on the same days of
          the month) = 18.6 ~= 19
        
         moon phase on first day of year (epact) ~= (11*(year%19) + 18) % 30
          (18 as initial condition for 1900)
        
         current phase in days = first day phase + days elapsed in year
        
         6 moons ~= 177 days
         177 ~= 8 reported phases * 22
         + 11 / 22 for rounding
         
        Parameters:
        cal - the calendar.
        Returns:
        The phase of the moon as a number between 0 and 7 with 0 meaning new moon and 4 meaning full moon.
        Since:
        1.2, Ant 1.5
      • getDateForHeader

        public static java.lang.String getDateForHeader()
        Returns the current Date in a format suitable for a SMTP date header.
        Returns:
        the current date.
        Since:
        Ant 1.5.2
      • parseDateFromHeader

        public static java.util.Date parseDateFromHeader​(java.lang.String datestr)
                                                  throws java.text.ParseException
        Parses the string in a format suitable for a SMTP date header.
        Parameters:
        datestr - string to be parsed
        Returns:
        a java.util.Date object as parsed by the format.
        Throws:
        java.text.ParseException - if the supplied string cannot be parsed by this pattern.
        Since:
        Ant 1.8.0
      • parseIso8601DateTime

        public static java.util.Date parseIso8601DateTime​(java.lang.String datestr)
                                                   throws java.text.ParseException
        Parse a string as a datetime using the ISO8601_DATETIME format which is yyyy-MM-dd'T'HH:mm:ss
        Parameters:
        datestr - string to be parsed
        Returns:
        a java.util.Date object as parsed by the format.
        Throws:
        java.text.ParseException - if the supplied string cannot be parsed by this pattern.
        Since:
        Ant 1.6
      • parseIso8601Date

        public static java.util.Date parseIso8601Date​(java.lang.String datestr)
                                               throws java.text.ParseException
        Parse a string as a date using the ISO8601_DATE format which is yyyy-MM-dd
        Parameters:
        datestr - string to be parsed
        Returns:
        a java.util.Date object as parsed by the format.
        Throws:
        java.text.ParseException - if the supplied string cannot be parsed by this pattern.
        Since:
        Ant 1.6
      • parseIso8601DateTimeOrDate

        public static java.util.Date parseIso8601DateTimeOrDate​(java.lang.String datestr)
                                                         throws java.text.ParseException
        Parse a string as a date using the either the ISO8601_DATETIME or ISO8601_DATE formats.
        Parameters:
        datestr - string to be parsed
        Returns:
        a java.util.Date object as parsed by the formats.
        Throws:
        java.text.ParseException - if the supplied string cannot be parsed by either of these patterns.
        Since:
        Ant 1.6
      • parseLenientDateTime

        public static java.util.Date parseLenientDateTime​(java.lang.String dateStr)
                                                   throws java.text.ParseException
        Parse a lenient ISO 8601, ms since epoch, or <touch>-style date. That is:
        • Milliseconds since 1970-01-01 00:00
        • YYYY-MM-DD{T| }HH:MM[:SS[.SSS]][ ][±ZZ[[:]ZZ]]
        • MM/DD/YYYY HH:MM[:SS] {AM|PM}
        where {a|b} indicates that you must choose one of a or b, and [c] indicates that you may use or omit c. ±ZZZZ is the timezone offset, and may be literally "Z" to mean GMT.
        Parameters:
        dateStr - String
        Returns:
        Date
        Throws:
        java.text.ParseException - if date string does not match ISO 8601
        Since:
        Ant 1.10.2