* Scheduler에 쓰이는 Cron 표현식에 대한 정리.
Cron expressions are used to configure instances of CronTrigger, a subclass of org.quartz.Trigger. A cron expression is a string consisting of six or seven subexpressions (fields) that describe individual details of the schedule.
These fields, separated by white space, can contain any of the allowed values with various combinations of the allowed characters for that field. Table A-1 shows the fields in the expected order.
Cron expressions can be as simple as * * * * ? *
or as complex as 0 0/5 14,18,3-39,52 ? JAN,MAR,SEP MON-FRI 2002-2010
.
Here are some more examples:
Example)
Cron 표현식(Expression)
| Graphically, the cron syntax for Quarz is (source): +-------------------- second (0 - 59)
| +----------------- minute (0 - 59)
| | +-------------- hour (0 - 23)
| | | +----------- day of month (1 - 31)
| | | | +-------- month (1 - 12)
| | | | | +----- day of week (0 - 6) (Sunday=0 or 7)
| | | | | | +-- year [optional]
| | | | | | |
* * * * * * * command to be executed
So if you want to run a command every 30 minutes you can say either of these: 0 0/30 * * * * ?
0 0,30 * * * * ?
|
참조
https://docs.oracle.com/cd/E12058_01/doc/doc.1014/e12030/cron_expressions.htm