How to create a TitlePropertyListener in CQ5?

1)Directory structure:

  
2)com.anshu.anshuapps.bnd:
Export-Package: com.anshu.anshuapps
Private-Package: com.anshu.anshuapps.impl
Bundle-Name: mywebsite
Bundle-Description: Contains the mywebsite sample bundle
Bundle-SymbolicName: com.anshu.anshuapps
Bundle-Version: 1.0-SNAPSHOT
Bundle-Activator: com.anshu.anshuapps.impl.Activator
3)TitlePropertyListener java file:-
package com.anshu.anshuapps;

import javax.jcr.Node;
import javax.jcr.NodeIterator;
import javax.jcr.Property;
import javax.jcr.RepositoryException;
import javax.jcr.Session;
import javax.jcr.observation.Event;
import javax.jcr.observation.EventIterator;
import javax.jcr.observation.EventListener;
import javax.jcr.observation.ObservationManager;

import org.apache.felix.scr.annotations.Reference;
import org.apache.sling.jcr.api.SlingRepository;
import org.osgi.service.component.ComponentContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.felix.scr.annotations.Component;

@Component
public class TitlePropertyListener implements EventListener {
   
    private final Logger LOGGER = LoggerFactory.getLogger(TitlePropertyListener.class);
   
    @Reference
    private SlingRepository repository;
   
    private Session session;
    private ObservationManager observationManager;
   
    protected void activate(ComponentContext context) throws Exception {
        session = repository.loginAdministrative(null);
        observationManager = session.getWorkspace().getObservationManager();
       
        observationManager.addEventListener(this, Event.PROPERTY_ADDED | Event.PROPERTY_CHANGED, "/", true, null,
                null, true);
        LOGGER.info("********added JCR event listener");
    }
   
    protected void deactivate(ComponentContext componentContext) {
        try {
            if (observationManager != null) {
                observationManager.removeEventListener(this);
                LOGGER.info("********removed JCR event listener");
            }
        }
        catch (RepositoryException re) {
            LOGGER.error("********error removing the JCR event listener", re);
        }
        finally {
            if (session != null) {
                session.logout();
                session = null;
            }
        }
    }
   
    public void onEvent(EventIterator it) {
        while (it.hasNext()) {
            Event event = it.nextEvent();
            try {
                LOGGER.info("********new property event: {}", event.getPath());
              
                Property changedProperty = session.getProperty(event.getPath());
                        if (changedProperty.getName().equalsIgnoreCase("jcr:title")
                                    && !changedProperty.getString().endsWith("!"))
                        {
                              changedProperty.setValue(changedProperty.getString() + "!");
                              session.save();
                        }
            }
            catch (Exception e) {
                LOGGER.error(e.getMessage(), e);
            }
        }      
    }
  }