org.apache.tools.ant.util
Class DateUtils

java.lang.Object
  extended by org.apache.tools.ant.util.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 plurialization correct elapsed time in minutes and seconds.

Since:
Ant 1.5

Field Summary
static java.text.DateFormat DATE_HEADER_FORMAT
          Format used for SMTP (and probably other) Date headers.
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
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 format(long 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 plurialization 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 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.
 
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

public static final java.text.DateFormat DATE_HEADER_FORMAT
Format used for SMTP (and probably other) Date headers.

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 plurialization correct string. It is limited only to report elapsed time in minutes and seconds and has the following behavior.

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 calander.
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

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