Hi Arun,
I have gone through the documentation. Still Haven't clear few things.
When to use Apache Sling Logger Service and when to use Apache Felix logs(org.osgi.service.log.Logger)?
As per my understanding ,
Apache Sling Logger Service can be used for logging components(Sling models, sling servlets, etc), as shown
protected final Logger log = LoggerFactory.getLogger(this.getClass());
log.info(" logging configuration service");
Apache Felix Log(org.osgi.service.log.Logger) -I don't know when to use it
Also when i go to following path in web console( webconsole -> osgi tab -> log )It always show empty and log service is running.

Please assist me regarding following concept.
Regards,
Shridhar