how to use spring job

 Using the OpenSymphony Quartz Scheduler
Quartz uses Trigger, Job and JobDetail objects to realize scheduling of all kinds of jobs. For the basic
concepts behind Quartz, have a look at http://www.opensymphony.com/quartz. For convenience purposes,
Spring offers a couple of classes that simplify the usage of Quartz within Spring-based applications.
23.2.1. Using the JobDetailBean
JobDetail objects contain all information needed to run a job. The Spring Framework provides a
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 in 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
}
}
Spring Framework (2.0.6) 409
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 matches the bean name of the job detail bean (in the example above, this is
exampleJob).
23.2.2. Using the MethodInvokingJobDetailFactoryBean
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 method being called on the exampleBusinessObject method (see
below):
public class ExampleBusinessObject {
// 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 classes 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>