Vadim Loginov

NAME

DateTime::Event::Cron::Quartz - OpensSymphony Quartz cron expression processor

SYNOPSIS

    use DateTime::Event::Cron::Quartz;

    # 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);

    print $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




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