Create a Service with Java that runs when the app is deoployed ?

Question

I have a Web Application with J2EE and Spring, related to an Oracle 10g Database. I want to create a Service in Java that will poll statistics from the Database and send mail every 5 min. This Service should start when the application is deployed under Tomcat or Web-sphere. Any Ideas How this could be done ?? Thanks

Answer 1

Since use Spring, its Time execution and scheduling classes seem a natural choice. They work both in Tomcat and Websphere, just create your task as a POJO and schedule it:

<bean id="PollingTask" class="com.sth.PollingPOJO">
         <!-- properties, if any -->
</bean>

<task:scheduler id="scheduler" pool-size="1" />

<task:scheduled-tasks scheduler="scheduler">
    <!-- runs every 30 minutes -->
    <task:scheduled ref="PollingTask" method="run" fixed-delay="#{ 30*60*1000 }" />
</task:scheduled-tasks>

The PollingTask looks like (note that it doesn't have to implement Runnable, "run" method is just a convention):

class PollingTask() {
    public void run() {
        // entry point
    }
}