Quartz Spring CronTrigger fired more times than configured

Question

I have a cronTrigger for a job "digestJob":

<bean id="digestCronTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean"> 
    <property name="jobDetail" ref="digestJob" />
    <property name="cronExpression" value="0 35 15 * * ?" />
</bean>

Here is my schedulerFactoryBean configuration:

<bean class="org.springframework.scheduling.quartz.SchedulerFactoryBean">
        <property name="triggers">
            <list>
                <ref bean="digestCronTrigger" />   
            </list>
        </property>
    </bean>

The problem is, the digestCronTrigger is supposed to be fired ONCE everyday at 5:35 PM, but it is being fired TWICE at the specified time. However, when I use SimpleTrigger:

<bean id="digestTrigger" class="org.springframework.scheduling.quartz.SimpleTriggerBean">
        <property name="jobDetail" ref="digestJob" />
        <property name="startDelay" value="0" />
        <property name="repeatInterval" value="10000" />
    </bean>

everything works fine and the trigger is fired exactly once every 10 seconds. Why digestCronTrigger is being fired twice? Is there something wrong with my cron expression, or is there any property that I am missing? Any help will be much appreciated.

Answer 1

I posted same question at springsource forums where I got help to figure out the cause behind the problem: I was loading the application context twice. Later I found from this post how to avoid loading the context twice. Now things are working fine.

Answer 2

This can also happen if you're creating a trigger when you're starting your application and are using a datasource in your quartz.properties file. Every time you start your server it will write a new trigger to the QRTZ_CRON_TRIGGERS and QRTZ_TRIGGERS tables and use all of them on each restart.

Answer 3

Try this:

    <bean class="org.springframework.scheduling.quartz.SchedulerFactoryBean">
        <property name="triggers">
            <list>
                <ref bean="cronTrigger" />
            </list>
        </property>
    </bean>

    <bean id="jobDetail" class="org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean">
      <property name="targetObject" ref="actionObject" />
      <property name="targetMethod" value="actionMethod" />
    </bean>

    <bean id="cronTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean">
        <property name="jobDetail" ref="jobDetail"/>
        <property name="cronExpression" value="0 15 17 * * ?"/>
    </bean>