NAME
DateTime::Event::Cron::Quartz - OpensSymphony Quartz cron expression processor
SYNOPSIS
# object construction
my
$event
= DateTime::Event::Cron::Quartz->new(
'0 0 12 * * ?'
);
# get the next event occurrence
my
$next_date
=
$event
->get_next_valid_time_after(DateTime->now);
$next_date
->datetime;
# check if it was a correct cron expression provided
my
$is_valid
=
$event
->is_valid_expression(
'0 0 12 * * ?'
);
DESCRIPTION
Documentation is taken from tutorial http://www.opensymphony.com/quartz/wikidocs/CronTriggers%20Tutorial.html and api javadoc http://www.opensymphony.com/quartz/api/org/quartz/CronExpression.html
Format
A cron expression is a string comprised of 6 or 7 fields separated by white space. Fields can contain any of the allowed values, along with various combinations of the allowed special characters for that field. The fields are as follows:
Field Name Mandatory? Allowed Values Allowed Special Characters
Seconds YES 0-59 , - * /
Minutes YES 0-59 , - * /
Hours YES 0-23 , - * /
Day of month YES 1-31 , - * ? / L W
Month YES 1-12 or JAN-DEC , - * /
Day of week YES 1-7 or MON-SUN , - * ? / L
#
Year NO empty, 1970-2099 , - * /
So cron expressions can be as simple as this: * * * * ? * or more complex, like this: 0 0/5 14,18,3-39,52 ? JAN,MAR,SEP MON-FRI 2002-2010
Special characters
* * (
"all values"
) - used to
select
all
values
within a field.
For example,
"*"
in the minute field means
"every minute"
.
* ? (
"no specific value"
) - useful
when
you need to specify something
in one of the two fields in which the character is allowed,
but not the other. For example,
if
I want
my
trigger to fire on a
particular day of the month (
say
, the 10th), but don't care what day
of the week that happens to be, I would put
"10"
in the
day-of-month field, and
"?"
in the day-of-week field.
See the examples below
for
clarification.
* - - used to specify ranges. For example,
"10-12"
in the hour field
means
"the hours 10, 11 and 12"
.
* , - used to specify additional
values
. For example,
"MON,WED,FRI"
in the day-of-week field means
"the days Monday, Wednesday, and Friday"
.
* / - used to specify increments. For example,
"0/15"
in the seconds
field means
"the seconds 0, 15, 30, and 45"
. And
"5/15"
in the seconds
field means
"the seconds 5, 20, 35, and 50"
. You can also
specify
'/'
after
the
''
character - in this case
''
is equivalent to
having
'0'
before
the
'/'
.
'1/3'
in the day-of-month field means
"fire every 3 days starting on the first day of the month"
.
* L (
"last"
) -
has
different meaning in
each
of the two fields in which it
is allowed. For example, the value
"L"
in the day-of-month field means
"the last day of the month"
- day 31
for
January, day 28
for
February
on non-leap years. If used in the day-of-week field by itself, it
simply means
"7"
or
"SAT"
. But
if
used in the day-of-week field
after
another value, it means
"the last xxx day of the month"
-
for
example
"6L"
means
"the last friday of the month"
.
When using the
'L'
option, it is important not to specify lists, or
ranges of
values
, as you'll get confusing results.
* W (
"weekday"
) - used to specify the weekday (Monday-Friday) nearest the
given
day. As an example,
if
you were to specify
"15W"
as the value
for
the day-of-month field, the meaning is: "the nearest weekday to the 15th
of the month". So
if
the 15th is a Saturday, the trigger will fire on
Friday the 14th. If the 15th is a Sunday, the trigger will fire
on Monday the 16th. If the 15th is a Tuesday, then it will fire on
Tuesday the 15th. However
if
you specify
"1W"
as the value
for
day-of-month, and the 1st is a Saturday, the trigger will fire on
Monday the 3rd, as it will not
'jump'
over the boundary of a
month
's days. The '
W' character can only be specified
when
the
day-of-month is a single day, not a range or list of days.
The
'L'
and
'W'
characters can also be combined in the day-of-month field
to yield
'LW'
, which translates to
"last weekday of the month"
.
*
# - used to specify "the nth" XXX day of the month.
For example, the value of
"6#3"
in the day-of-week field means
"the third Friday of the month"
(day 6 = Friday and
"#3"
= the 3rd one in the month).
Other examples:
"2#1"
= the first Monday of the month and
"4#5"
= the fifth Wednesday of the month. Note that
if
you specify
"#5"
and there is not 5 of the
given
day-of-week in the month,
then
no
firing will occur that month.
The legal characters and the names of months and days of the week are not
case sensitive. MON is the same as mon.
Examples
Expression Meaning
0 0 12 * * ? Fire at 12pm (noon) every day
0 15 10 ? * * Fire at 10:15am every day
0 15 10 * * ? Fire at 10:15am every day
0 15 10 * * ? * Fire at 10:15am every day
0 15 10 * * ? 2005 Fire at 10:15am every day during the year 2005
0 * 14 * * ? Fire every minute starting at 2pm and
ending at 2:59pm, every day
0 0/5 14 * * ? Fire every 5 minutes starting at 2pm and
ending at 2:55pm, every day
0 0/5 14,18 * * ? Fire every 5 minutes starting at 2pm and ending
at 2:55pm, AND fire every 5 minutes starting
at 6pm and ending at 6:55pm, every day
0 0-5 14 * * ? Fire every minute starting at 2pm and
ending at 2:05pm, every day
0 10,44 14 ? 3 WED Fire at 2:10pm and at 2:44pm every Wednesday
in the month of March.
0 15 10 ? * MON-FRI Fire at 10:15am every Monday, Tuesday,
Wednesday, Thursday and Friday
0 15 10 15 * ? Fire at 10:15am on the 15th day of every month
0 15 10 L * ? Fire at 10:15am on the
last
day of every month
0 15 10 ? * 5L Fire at 10:15am on the
last
Friday of every month
0 15 10 ? * 5L Fire at 10:15am on the
last
Friday of every month
0 15 10 ? * 5L 2002-2005 Fire at 10:15am on every
last
friday of every
month during the years 2002, 2003, 2004 and 2005
0 15 10 ? * 5
#3 Fire at 10:15am on the third Friday of every month
0 0 12 1/5 * ? Fire at 12pm (noon) every 5 days every month,
starting on the first day of the month.
0 11 11 11 11 ? Fire every November 11th at 11:11am.
Pay attention to the effects of '?' and '*' in the day-of-week and day-of-month fields!
SUBROUTINES/METHODS
- new($cron_expression)
-
Returns a DateTime::Event::Cron::Quartz object which parses and builds unix-like cron expressions. If it was an error during expression parsing ParseException is thrown.
- get_next_valid_time_after($after_datetime)
-
Returns the next date/time after the given date/time which satisfies the cron expression.
- is_valid_expression($cron_expression)
-
Indicates whether the specified cron expression can be parsed into a valid cron expression.
BUGS AND LIMITATIONS
* This module is not compatible with unix crontab format. If you are going to use it for unix crontab processing you should make following changes to it: add seconds field and set one of day-of-week or day-of-month fields to unspecified ('?' character)
* Support for specifying both a day-of-week and a day-of-month value is not complete (you must currently use the '?' character in one of these fields).
* Be careful when setting fire times between mid-night and 1:00 AM - "daylight savings" can cause a skip or a repeat depending on whether the time moves back or jumps forward.
AUTHOR
Vadim Loginov <vadim.loginov@gmail.com>
COPYRIGHT AND LICENSE
Based on the source code and documentation of OpenSymphony http://www.opensymphony.com/team.jsp Quartz 1.4.2 project licensed under the Apache License, Version 2.0
Copyright (c) 2009 Vadim Loginov.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
VERSION
0.05
SEE ALSO
DateTime(3), http://www.opensymphony.com/quartz/api/org/quartz/CronExpression.html