Running multiple instances of a quartz job dynamically

I have been facing a problem of running configurable number of instances of the same job to consume the traffic that was varying over time. In order to dynamically create an instance of a job and run it immediately, I googled and found some interesting facts like each trigger is fired with a new instance of the job. We can create any no. of trigger for a job.

Here is a sample code to dynamically create a new trigger for a job and scheduling it to run immediately…
[groovy]
//import org.codehaus.groovy.grails.plugins.quartz.GrailsTaskClassProperty as GTCP
//import org.codehaus.groovy.grails.plugins.quartz.GrailsTaskClass
//import org.quartz.Trigger
//import org.quartz.SimpleTrigger
// def quartzScheduler /*inject qartzScheduler bean*/

GrailsTaskClass tc=grailsApplication.taskClasses.find{it.fullName==’myPackage.MySampleJob’}
// fully packaged name of the Job. There may be better way to find the Grails Job.

String triggerName=’mytrigger’+System.currentTimeMillis() // unique trigger name

Trigger trigger = new SimpleTrigger(triggerName,
GTCP.DEFAULT_TRIGGERS_GROUP,
tc.getFullName(),
tc.getGroup(),
new Date(),
null, 0, 1000)
/*
Created a simple trigger using constructor :

SimpleTrigger(String name, String group, String jobName, String jobGroup, Date startTime, Date endTime, int repeatCount, long repeatInterval)
*/

trigger.jobDataMap.putAll([‘triggerName’:triggerName, ‘myData’:1000])

/*
passing map to the trigger that can be accessed inside execute() method of the job using context.mergedJobDataMap
*/

quartzScheduler.scheduleJob(trigger) //execute the job for this trigger.
[/groovy]
The above sample code can be used to create any number of triggers that are executed with a new instance of the specified Quartz Job.

Helpful Links :

1.
2. Quartz Plugin source code(QuartzGrailsPlugin.groovy)

Hope it helps you.

~~~~Bhagwat Kumar~~~~
bhagwat@intelligrape.com
IntelliGrape Software