Create a Scheduler in Liferay

In this small blog we will give an understanding of how can we write a Scheduler to run a cron job for performing a background job on the portal. 

Step 1 : Create a scheduler class in your portlet

import com.liferay.portal.kernel.messaging.Message;
import com.liferay.portal.kernel.messaging.MessageListener;
import com.liferay.portal.kernel.messaging.MessageListenerException;

public class NewsLetterScheduler implements MessageListener {

  public void receive(Message arg0) throws MessageListenerException {

       System.out.println("newsletter received!!!");

        /* Add your business logic here*/

  }

}

Step 2 : Specify the path in the liferay-portlet.xml.

The class name specified in the liferay-portlet.xml must match with scheduler class.

<portlet>
<portlet-name>newsletter-portlet</portlet-name>
<icon>/icon.png</icon>
<scheduler-entry>
    <scheduler-description>
       scheduler will run on every 15 minutes
    </scheduler-description>
    <scheduler-event-listener-class>

      com.sa.newsletter.trigger.NewsLetterScheduler</scheduler-event-listener-class>
 

   <trigger>
       <simple>
          <simple-trigger-value>15</simple-trigger-value>
          <time-unit>minute</time-unit>
       </simple>

  

        <!--<cron>
            <cron-trigger-value>0 0 0 * * ?</cron-trigger-value>
        </cron> -->

  </trigger>
</scheduler-entry>
</portlet>

This (<cron-trigger-value>0 0 0 * * ?</cron-trigger-value>) indicates that the scheduler will run every night at 00 hrs.

<cron>
    <cron-trigger-value>0 0 0 * * ?</cron-trigger-value>
</cron>

I Hope this small blog helps you a lot!!!