containerschangeeventlistener.java

java 写的一个新闻发布系统

//
//                                   ____.
//                       __/\ ______|    |__/\.     _______
//            __   .____|    |       \   |    +----+       \
//    _______|  /--|    |    |    -   \  _    |    :    -   \_________
//   \\______: :---|    :    :           |    :    |         \________>
//           |__\---\_____________:______:    :____|____:_____\
//                                      /_____|
//
//                 . . . i n   j a h i a   w e   t r u s t . . .
//
//
//
//
// 28.05.2002 NK Creation



package org.jahia.data.containers;


import java.util.*;
import java.util.Date;
import java.util.TimeZone;
import java.util.Calendar;

import org.jahia.utils.*;               			// JahiaConsole
import org.jahia.exceptions.*;                      // Jahia Exceptions
import org.jahia.data.events.*;                     // EventObject
import org.jahia.data.containers.*;                 // JahiaContainers
import org.jahia.services.usermanager.*;            // JahiaUser

/**
 * Listener for containers and container list change events.
 * Created for container search caching purpose.
 * You must access this Singleton through JahiaListenersRegistry
 *
 * @see JahiaListenersRegistry
 * @author Khue Nguyen <a href="mailto:[e-mail]">[e-mail]</a>
 */
public class ContainersChangeEventListener extends JahiaEventListener
{

	private static final String CLASS_NAME = ContainersChangeEventListener.class.getName();

	private static Hashtable ctnListsLastChanges = new Hashtable();

	private static Hashtable containersLastChanges = new Hashtable();

	//--------------------------------------------------------------------------
	/**
     * triggered when Jahia adds a container
     *
     * @param je the associated JahiaEvent
     */
    public void containerAdded( JahiaEvent je ) {
        JahiaConsole.println("ContainersChangeEventListener.containerAdded","Started");
        JahiaContainer theObject    = (JahiaContainer) je.getObject();
   	 	notifyChange(theObject);
    }

	//--------------------------------------------------------------------------
	/**
     * triggered when Jahia updates a container
     *
     * @param je the associated JahiaEvent
     */
    public void containerUpdated( JahiaEvent je ) {
        JahiaConsole.println("ContainersChangeEventListener.containerUpdated","Started");
        JahiaContainer theObject    = (JahiaContainer) je.getObject();
   	 	notifyChange(theObject);
    }

	//--------------------------------------------------------------------------
	/**
     * triggered when Jahia adds a container
     *
     * @param je the associated JahiaEvent
     */
    public void containerDeleted( JahiaEvent je ) {
        JahiaConsole.println("ContainersChangeEventListener.containerAdded","Started");
        JahiaContainer theObject    = (JahiaContainer) je.getObject();
   	 	notifyChange(theObject);
    }

	//--------------------------------------------------------------------------
	/**
     * set the last modifying time for the given container, the container list containing the container is updated too.
     *
     * @param JahiaContainer the container.
     */
    public void notifyChange( JahiaContainer theContainer  ) {

        if ( theContainer == null ){
        	return;
        }

	 	// Set search time
        TimeZone tz = TimeZone.getTimeZone("UTC");
        Calendar cal = Calendar.getInstance(tz);
	 	Date nowDate = cal.getTime();
		long now = nowDate.getTime();
		
		containersLastChanges.put(new Integer(theContainer.getID()),new Long(now));
		ctnListsLastChanges.put(new Integer(theContainer.getListID()),new Long(now));
    }


	//--------------------------------------------------------------------------
	/**
     * Returns the last modifying time for the given container list.
     *
     * @param int ctnListID, the container list id.
     * @return long time, the last change time. -1 if information not available.
     */
    public static long getCtnListLastChangeTime( int ctnListID ) {

		Long L = (Long)ctnListsLastChanges.get(new Integer(ctnListID));
		if ( L == null ){
			return -1;
		}
		try {
			return L.longValue();
		} catch ( Throwable t ){
		}
		return -1;	
    }

	//--------------------------------------------------------------------------
	/**
     * Returns the last modifying time for the given container.
     *
     * @param int ctnID, the container id.
     * @return long time, the last change time. -1 if information not available.
     */
    public static long getContainerLastChangeTime( int ctnID ) {

		Long L = (Long)containersLastChanges.get(new Integer(ctnID));
		if ( L == null ){
			return -1;
		}
		try {
			return L.longValue();
		} catch ( Throwable t ){
		}
		return -1;	
    }

} // end ContainersChangeEventListener