Cron Triggers

Use CronTrigger for schedules based on calendar notions rather than the fixed intervals of SimpleTrigger: "every Friday at noon", "every weekday at 9:30 am", or "every 5 minutes between 9:00 am and 10:00 am on every Monday, Wednesday and Friday".

Like SimpleTrigger, CronTrigger has a start time from which the schedule is in force, and an optional end time at which it stops.

Cron Expressions

A cron expression is a string of 6 or 7 fields separated by white space. Each field takes its allowed values and special characters:

0 0 12 ? * WED means "every Wednesday at 12:00 pm".

• Ranges and lists. The day-of-week field WED could be MON-FRI, MON, WED, FRI or MON-WED,SAT.
• Wild-card. * means every value of the field: every month in the Month field, every day in the Day-Of-Week field.
• Values. Seconds and minutes 0 to 59; hours 0 to 23; day-of-month 1-31 (mind how many days a month has); months 1 to 12 or JAN, FEB, MAR, APR, MAY, JUN, JUL, AUG, SEP, OCT, NOV and DEC; days-of-week 1 to 7 (1 = Sunday) or SUN, MON, TUE, WED, THU, FRI and SAT.
• / sets increments. 0/15 in Minutes means every 15 minutes starting at minute zero. 3/20 means every 20 minutes starting at minute three, the same as 3,23,43.
• ? ("no specific value") is allowed in day-of-month and day-of-week, to set one of the two and leave the other open.
• L ("last") is allowed in day-of-month and day-of-week, with a different meaning in each. In day-of-month it is the last day of the month: day 31 for January, day 28 for February in non-leap years. In day-of-week on its own it means "7" or "SAT"; after another value it means "the last xxx day of the month", so 6L and FRIL both mean the last Friday of the month. Do not combine L with lists or ranges; the results are confusing.
• W is the weekday (Monday-Friday) nearest the given day. 15W in day-of-month means the nearest weekday to the 15th.
• # is "the nth" XXX weekday of the month. 6#3 or FRI#3 in day-of-week means the third Friday of the month.
• H (hash) spreads triggers evenly across time. It resolves to a deterministic value derived from the trigger's identity (name and group), so triggers with the same expression fire at different times. 0 H H(0-7) * * ? fires once per day between midnight and 7:59 AM at a trigger-specific time; 0 H/15 * * * ? fires every 15 minutes from a hash-derived offset. With the builder API, call WithIdentity() so the hash comes from a stable identity.

The CronTrigger Tutorial has the full syntax and more examples.

Example Cron Expressions

More examples are in the API documentation for CronTrigger.

Every 5 minutes:

    "0 0/5 * * * ?"

Every 5 minutes, at 10 seconds after the minute (10:00:10 am, 10:05:10 am, etc.):

    "10 0/5 * * * ?"

At 10:30, 11:30, 12:30 and 13:30, every Wednesday and Friday:

    "0 30 10-13 ? * WED,FRI"

Every half hour between 8 am and 10 am on the 5th and 20th of every month. It does NOT fire at 10:00 am, only at 8:00, 8:30, 9:00 and 9:30:

    "0 0/30 8-9 5,20 * ?"

Some schedules are too complex for one trigger, such as "every 5 minutes between 9:00 am and 10:00 am, and every 20 minutes between 1:00 pm and 10:00 pm". Create two triggers and register both for the same job.

Building CronTriggers

Build CronTrigger instances with TriggerBuilder (the trigger's main properties) and the WithCronSchedule extension method (the CronTrigger-specific properties). CronScheduleBuilder's static methods also create schedules. To compose the expression string itself in code, see Building cron expressions programmatically.

Every other minute, between 8am and 5pm, every day:

ITrigger trigger = TriggerBuilder.Create()
    .WithIdentity("trigger3", "group1")
    .WithCronSchedule("0 0/2 8-17 * * ?")
    .ForJob("myJob", "group1")
    .Build();

Daily at 10:42 am:

// we use CronScheduleBuilder's static helper methods here
ITrigger trigger = TriggerBuilder.Create()
    .WithIdentity("trigger3", "group1")
    .WithSchedule(CronScheduleBuilder.DailyAtHourAndMinute(10, 42))
    .ForJob(myJobKey)
    .Build();

or:

ITrigger trigger = TriggerBuilder.Create()
    .WithIdentity("trigger3", "group1")
    .WithCronSchedule("0 42 10 * * ?")
    .ForJob("myJob", "group1")
    .Build();

Wednesdays at 10:42 am, in a time zone other than the system's default:

ITrigger trigger = TriggerBuilder.Create()
    .WithIdentity("trigger3", "group1")
    .WithSchedule(CronScheduleBuilder
        .WeeklyOnDayAndHourAndMinute(DayOfWeek.Wednesday, 10, 42)
        .InTimeZone(TimeZoneInfo.FindSystemTimeZoneById("Central America Standard Time")))
    .ForJob(myJobKey)
    .Build();

or:

ITrigger trigger = TriggerBuilder.Create()
    .WithIdentity("trigger3", "group1")
    .WithCronSchedule("0 42 10 ? * WED", x => x
        .InTimeZone(TimeZoneInfo.FindSystemTimeZoneById("Central America Standard Time")))
    .ForJob(myJobKey)
    .Build();

Once per day at a hash-derived time between midnight and 7:59 AM, spreading load across triggers:

ITrigger trigger = TriggerBuilder.Create()
    .WithIdentity("nightly-cleanup", "maintenance")
    .WithCronSchedule("0 H H(0-7) * * ?")
    .ForJob("cleanupJob", "maintenance")
    .Build();

CronTrigger Misfire Instructions

These constants tell Quartz what to do when a CronTrigger misfires (see More About Triggers for misfires; the API documentation describes each one):

• MisfireInstruction.IgnoreMisfirePolicy
• MisfireInstruction.CronTrigger.DoNothing
• MisfireInstruction.CronTrigger.FireOnceNow

Every trigger type also has MisfireInstruction.SmartPolicy, the default. CronTrigger interprets it as MisfireInstruction.CronTrigger.FireOnceNow; the API documentation for CronTrigger.UpdateAfterMisfire() has the details.

Set the misfire instruction as part of the cron schedule, in WithCronSchedule:

ITrigger trigger = TriggerBuilder.Create()
    .WithIdentity("trigger3", "group1")
    .WithCronSchedule("0 0/2 8-17 * * ?", x => x
        .WithMisfireHandlingInstructionFireAndProceed())
    .ForJob("myJob", "group1")
    .Build();