JobDetail objects contain all information needed to run a job. Spring provides a so-called JobDetailBean that makes the JobDetail more of an actual JavaBean with sensible defaults. Let's have a look at an example:

<bean name="exampleJob" class="org.springframework.scheduling.quartz.JobDetailBean">
  <property name="jobClass" value="example.ExampleJob"/>
  <property name="jobDataAsMap">
    <map>
      <entry key="timeout" value="5"/>
    </map>
  </property>
</bean>
			

The job detail bean has all information it needs to run the job (ExampleJob). The timeout is specified as the job data map. The job data map is available through the JobExecutionContext (passed to you at execution time), but the JobDetailBean also maps the properties from the job data map to properties of the actual job. So in this case, if the ExampleJob contains a property named timeout, the JobDetailBean will automatically apply it:

package example;

public class ExampleJob extends QuartzJobBean {

  private int timeout;
  
  /**
   * Setter called after the ExampleJob is instantiated
   * with the value from the JobDetailBean (5)
   */ 
  public void setTimeout(int timeout) {
    this.timeout = timeout;
  }
  
  protected void executeInternal(JobExecutionContext ctx)
  throws JobExecutionException {
      // do the actual work
  }
}
			

All additional settings from the job detail bean are of course available to you as well.

Note: Using the name and group properties, you can modify the name and the group of the job, respectively. By default the name of the job equals the bean name of the job detail bean (in the example above, this is exampleJob).

Often you just need to invoke a method on a specific object. Using the MethodInvokingJobDetailFactoryBean you can do exactly this:

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

The above example will result in the doIt being called on the exampleBusinessObject (see below):

public class BusinessObject {
  
  // properties and collaborators
  
  public void doIt() {
    // do the actual work
  }
}
			

<bean id="exampleBusinessObject" class="examples.ExampleBusinessObject"/>
			

Using the MethodInvokingJobDetailFactoryBean you don't need to create one-line jobs that just invoke a method, and you only need to create the actual business object and wire up the detail object.

By default, Quartz Jobs are stateless, resulting in the possibility of jobs interfering with each other. If you specify two triggers for the same JobDetail, it might be possible that before the first job has finished, the second one will start. If JobDetail objects implement the Stateful interface, this won't happen. The second job will not start before the first one has finished. To make jobs resulting from the MethodInvokingJobDetailFactoryBean non-concurrent, set the concurrent flag to false.

<bean id="jobDetail" class="org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean">
  <property name="targetObject" ref="exampleBusinessObject"/>
  <property name="targetMethod" value="doIt"/>
  <property name="concurrent" value="false"/>
</bean>
			

Note: By default, jobs will run in a concurrent fashion.

We've created job details, jobs and we've reviewed the convenience bean that allows to you invoke a method on a specific object. Of course, we still need to schedule the jobs themselves. This is done using triggers and a SchedulerFactoryBean. Several triggers are available within Quartz. Spring offers two subclassed triggers with convenient defaults: CronTriggerBean and SimpleTriggerBean.

Triggers need to be scheduled. Spring offers a SchedulerFactoryBean exposing properties to set the triggers. SchedulerFactoryBean schedules the actual jobs with those triggers.

A couple of examples:

<bean id="simpleTrigger" class="org.springframework.scheduling.quartz.SimpleTriggerBean">
  <!-- see the example of method invoking job above -->
  <property name="jobDetail" ref="jobDetail"/>
	<!-- 10 seconds -->
  <property name="startDelay" value="10000"/>
	<!-- repeat every 50 seconds -->
  <property name="repeatInterval" value="50000"/>
</bean>

<bean id="cronTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean">
  <property name="jobDetail" ref="exampleJob"/>
	<!-- run every morning at 6 AM -->
  <property name="cronExpression" value="0 0 6 * * ?"/>
</bean>
			

OK, now we've set up two triggers, one running every 50 seconds with a starting delay of 10 seconds and one every morning at 6 AM. To finalize everything, we need to set up the SchedulerFactoryBean:

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

More properties are available for the SchedulerFactoryBean for you to set, such as the calendars used by the job details, properties to customize Quartz with, etc. Have a look at the JavaDoc (http://www.springframework.org/docs/api/org/springframework/scheduling/quartz/SchedulerFactoryBean.html) for more information.

Using the TimerTask you can create customer timer tasks, similar to Quartz jobs:

public class CheckEmailAddresses extends TimerTask {

  private List emailAddresses;
  
  public void setEmailAddresses(List emailAddresses) {
    this.emailAddresses = emailAddresses;
  }
  
  public void run() {
    // iterate over all email addresses and archive them
  }
}
			

Wiring it up is simple:

<bean id="checkEmail" class="examples.CheckEmailAddress">
  <property name="emailAddresses">
    <list>
      <value>[email protected]</value>
      <value>[email protected]</value>
      <value>[email protected]</value>
    </list>
  </property>
</bean>

<bean id="scheduledTask" class="org.springframework.scheduling.timer.ScheduledTimerTask">
  <!-- wait 10 seconds before starting repeated execution -->
  <property name="delay" value="10000"/>
  <!-- run every 50 seconds -->
  <property name="period" value="50000"/>
  <property name="timerTask" ref="checkEmail"/>
</bean>
			

Letting the task only run once can be done by changing the period property to -1 (or some other negative value)

Similar to the Quartz support, the Timer support also features a component that allows you to periodically invoke a method:

<bean id="doIt" class="org.springframework.scheduling.timer.MethodInvokingTimerTaskFactoryBean">
  <property name="targetObject" ref="exampleBusinessObject"/>
  <property name="targetMethod" value="doIt"/>
</bean>

The above example will result in the doIt being called on the exampleBusinessObject (see below):

public class BusinessObject {
  
  // properties and collaborators
  
  public void doIt() {
    // do the actual work
  }
}
			

Changing the reference of the above example (in which the ScheduledTimerTask is mentioned) to the doIt will result in this task being executed.

The TimerFactoryBean is similar to the Quartz SchedulerFactoryBean in that it serves the same purpose: setting up the actual scheduling. The TimerFactoryBean sets up an actual Timer and schedules the tasks it has references to. You can specify whether or not daemon threads should be used.

<bean id="timerFactory" class="org.springframework.scheduling.timer.TimerFactoryBean">
  <property name="scheduledTimerTasks">
    <list>
      <!-- see the example above -->
      <ref bean="scheduledTask"/>
    </list>
  </property>
</bean>
			

That's all!