liferay Create a Quartz scheduler in liferay Create a quartz scheduler to display some information

Example

In order to create a scheduler,the entry needs to be created in

liferay-portlet.xml

provding scheduler class and trigger value for timing of scheduler triggering

<portlet-name>GetSetGo</portlet-name>
        <icon>/icon.png</icon>
        <scheduler-entry>
        <scheduler-description>This scheduler logs User count from portal</scheduler-description>
            <scheduler-event-listener-class>com.example.scheduler.SchedulerSample</scheduler-event-listener-class>
            <trigger>
                 <simple>
                   <simple-trigger-value>
                     5
                   </simple-trigger-value>
                <time-unit>minute</time-unit>
            </simple>
            </trigger>
        </scheduler-entry>

The given entry provides

1. Scheduler description

2. Class name,which implements MessageListener class

3. Trigger,which provides intervals for defining trigger point for scheduler

   -Using Cron

   -Using Simple trigger value

In the given example,the scheduler will trigger after every 5 mins.

Next up we need to create scheduler class

package com.example.scheduler;

import com.liferay.portal.kernel.exception.SystemException;
import com.liferay.portal.kernel.log.Log;
import com.liferay.portal.kernel.log.LogFactoryUtil;
import com.liferay.portal.kernel.messaging.Message;
import com.liferay.portal.kernel.messaging.MessageListener;
import com.liferay.portal.kernel.messaging.MessageListenerException;
import com.liferay.portal.service.UserLocalServiceUtil;

public class SchedulerSample implements MessageListener {

    @Override
    public void receive(Message arg0) throws MessageListenerException {
        Log log=LogFactoryUtil.getLog(SchedulerSample.class);
        
        try {
            log.info("User Count for portal:"+UserLocalServiceUtil.getUsersCount());
        } catch (SystemException e) {
            
            log.info("User count is currently unavailable");
        }
        
    }

}

This scheduler simply displays output portal user count after every trigger interval to server console.