CopyPasteEventListener.java

package com.aemks.core.listeners;

import com.day.cq.commons.jcr.JcrConstants;
import com.day.cq.wcm.api.NameConstants;
import org.apache.jackrabbit.api.observation.JackrabbitEventFilter;
import org.apache.jackrabbit.api.observation.JackrabbitObservationManager;
import org.apache.sling.event.jobs.JobManager;
import org.apache.sling.jcr.api.SlingRepository;
import org.osgi.service.component.annotations.Activate;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Deactivate;
import org.osgi.service.component.annotations.Reference;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.jcr.RepositoryException;
import javax.jcr.Session;
import javax.jcr.Workspace;
import javax.jcr.observation.Event;
import javax.jcr.observation.EventIterator;
import javax.jcr.observation.EventListener;
import java.util.HashMap;

/**
 * This is a JCR event listener which listens to
 * copy/paste event in Touch UI.
 * (event = NODE_ADDED && event-user-data=changedByPageManagerCopy)
 */
@Component(service = EventListener.class, immediate = true)
public class CopyPasteEventListener implements EventListener {

    @Reference
    private SlingRepository repository;

    @Reference
    private JobManager jobManager;

    private final Logger logger = LoggerFactory.getLogger(getClass());

    private Session session; // NOSONAR

    private JackrabbitObservationManager observationManager;

    public static final String CHANGED_BY_PAGE_MANAGER_COPY = "changedByPageManagerCopy";

    public static final String EVENT_HANDLER_JOB="com/aemks/core/jobs/handleCopyPasteEvent";

    private final String[] nodeTypes = new String[] { NameConstants.NT_PAGE, JcrConstants.NT_UNSTRUCTURED };

    /**
     * The event handler delegates the event handling to
     * a sling job.
     * @param eventIterator the events iterator
     */
    @Override public void onEvent(EventIterator eventIterator) {

        while (eventIterator.hasNext()) {
            Event event = eventIterator.nextEvent();
            String path = null;
            try {
                path = event.getPath();
                if (CHANGED_BY_PAGE_MANAGER_COPY.equalsIgnoreCase(event.getUserData())) {
                    logger.info("Found the page event path {} triggered by {}", event.getPath(),
                            CHANGED_BY_PAGE_MANAGER_COPY);
                    HashMap<String, Object> jobProps = new HashMap<>();
                    jobProps.put("eventPath", path);
                    jobManager.addJob(EVENT_HANDLER_JOB, jobProps);
                    break;
                }
            } catch (RepositoryException e) {
                logger.error("An error occurred while getting event path",e);
            }

        }
    }

    /**
     * Login using the service user and register the event listener
     * for the appropriate content path, node types.
     */
    @Activate
    protected void activate() {
        try {
            session = repository.loginService("listener-service", null);

            JackrabbitEventFilter jackrabbitEventFilter = new JackrabbitEventFilter().setAbsPath("/content/aemks")
                    .setNodeTypes(nodeTypes).setEventTypes(Event.NODE_ADDED).setIsDeep(true).setNoExternal(true)
                    .setNoLocal(false);

            Workspace workSpace = session.getWorkspace();
            if (null != workSpace) {
                observationManager = (JackrabbitObservationManager) workSpace.getObservationManager();
                observationManager.addEventListener(this, jackrabbitEventFilter);
                logger.info("The Page Event Listener is Registered at {} for the event type {}.", "/content/aemks",
                        Event.NODE_ADDED);

            }
        } catch (RepositoryException e) {
            logger.error("An error occurred while getting session",e);
        }

    }

    /**
     * On deactivate, close/logout the long running session.
     */
    @Deactivate
    protected void deactivate() {
        try {
            if (null != observationManager) {
                observationManager.removeEventListener(this);
                logger.info("The Page Event Listener is removed.");
            }
        } catch (RepositoryException e) {
            logger.error("An error occurred while removing event listener",e);
        } finally {
            if (null != session) {
                session.logout();
            }
        }
    }
}