upnp.sample.clock/src/main/java/org/apache/felix/upnp/sample/clock/UPnPEventNotifier.java

/* 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.felix.upnp.sample.clock;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.Dictionary;
import java.util.Iterator;
import java.util.Properties;
import java.util.Vector;

import org.osgi.framework.BundleContext;
import org.osgi.framework.Constants;
import org.osgi.framework.Filter;
import org.osgi.framework.ServiceEvent;
import org.osgi.framework.ServiceListener;
import org.osgi.framework.ServiceReference;
import org.osgi.service.upnp.UPnPDevice;
import org.osgi.service.upnp.UPnPEventListener;
import org.osgi.service.upnp.UPnPService;
import org.osgi.service.upnp.UPnPStateVariable;

/* 
* @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a>
*/

public class UPnPEventNotifier implements PropertyChangeListener,ServiceListener {
	private BundleContext context;
	private UPnPDevice device;
	private UPnPService service;
	private EventSource source;
	
	private Properties UPnPTargetListener;
	private String deviceId;
	private String serviceId;
	private Vector upnpListeners = new Vector();
	final private Object LOCK = new Object();
	
	public UPnPEventNotifier(BundleContext context,UPnPDevice device,UPnPService service,EventSource source){
		this.context=context;
		this.device=device;
		this.service=service;
		this.source=source;
		this.serviceId=service.getId();
		setupUPnPListenerHouseKeeping(device);
	}
	
	/**
	 * @param deviceId
	 */
	private void setupUPnPListenerHouseKeeping(UPnPDevice device) {
		UPnPTargetListener = new Properties();
		Dictionary dict = device.getDescriptions(null);
		deviceId = (String) dict.get(UPnPDevice.ID);
		UPnPTargetListener.put(UPnPDevice.ID,deviceId);
		UPnPTargetListener.put(UPnPService.ID,serviceId);
		UPnPTargetListener.put(UPnPDevice.TYPE,dict.get(UPnPDevice.TYPE));
		UPnPTargetListener.put(UPnPService.TYPE,service.getType());
		String ANY_UPnPEventListener = "("+Constants.OBJECTCLASS+"="+UPnPEventListener.class.getName()+")";
		
		synchronized (LOCK) {
		    try {
		    	String filter = ANY_UPnPEventListener;
				context.addServiceListener(this,filter);
			} catch (Exception ex) {
				System.out.println(ex);
			}
			
			
			ServiceReference[] listeners = null; 
			try {
				listeners = context.getServiceReferences(UPnPEventListener.class.getName(),null);
				if (listeners != null){
					for (int i = 0;i<listeners.length;i++){
						ServiceReference sr = listeners[i];
						Filter filter = (Filter) sr.getProperty(UPnPEventListener.UPNP_FILTER);
						if (filter == null) upnpListeners.add(sr);
						else {				
							if (filter.match(UPnPTargetListener))
								addNewListener(sr);
						}
					}
				}
			} catch (Exception ex) {
				System.out.println(ex);
			}
		
		}

		if (source!=null){
			UPnPStateVariable[] vars = service.getStateVariables();
			if (vars != null){
				for (int i=0;i<vars.length;i++)
					if(vars[i].sendsEvents())
						source.addPropertyChangeListener(vars[i].getName(),this);
			}
		}
		
		
	}

	/* (non-Javadoc)
	 * @see java.beans.PropertyChangeListener#propertyChange(java.beans.PropertyChangeEvent)
	 */
	public void propertyChange(PropertyChangeEvent evt) {
		
		synchronized (LOCK) {
			
			Iterator list = upnpListeners.iterator();
			String property = evt.getPropertyName();
			Object value = evt.getNewValue();
			String valueString = value.toString();
			final Properties events = new Properties();
			events.put(property,valueString);
			while (list.hasNext()){
				final ServiceReference sr = (ServiceReference)list.next();
				String[] props =sr.getPropertyKeys();
				new Thread(){
					public void run(){
						try {
							UPnPEventListener listener = (UPnPEventListener) context.getService(sr);
							listener.notifyUPnPEvent(deviceId,serviceId,events);
							context.ungetService(sr);
						} catch (Exception ex){
							System.out.println("Clock UPnPEventNotifier Err: " +ex);
							System.out.println("context: " +context);
							System.out.println("listener: " +context.getService(sr));
							System.out.println("sr: " +sr);
							System.out.println();
						}
					}
				}.start();						
			}
		}
	}

	/* (non-Javadoc)
	 * @see org.osgi.framework.ServiceListener#serviceChanged(org.osgi.framework.ServiceEvent)
	 */
	public void serviceChanged(ServiceEvent e) {
		ServiceReference sr = e.getServiceReference();		
		synchronized (LOCK) {			
			switch(e.getType()){
				case ServiceEvent.REGISTERED:{
					Filter filter = (Filter) sr.getProperty(UPnPEventListener.UPNP_FILTER);
					if (filter == null) addNewListener(sr);
					else {				
						if (filter.match(UPnPTargetListener))
							addNewListener(sr);
					}
				};break;
				
				case ServiceEvent.MODIFIED:{				
		               Filter filter = (Filter)	sr.getProperty(UPnPEventListener.UPNP_FILTER);
		               removeListener(sr);
		               if (filter == null)
		                   addNewListener(sr);
		               else {
		                   if (filter.match(UPnPTargetListener))
		                       addNewListener(sr);
		               }
				};break;
				
				case ServiceEvent.UNREGISTERING:{	
					removeListener(sr);
				};break;					
			}
		}//end LOCK
		
	}

	/**
	 * @param reference
	 */
	private void removeListener(ServiceReference reference) {
		upnpListeners.remove(reference);		
	}

	/**
	 * @param reference
	 */
	private void addNewListener(ServiceReference reference) {
		upnpListeners.add(reference);	
	}
	
	public void destroy(){
		context.removeServiceListener(this);
		upnpListeners.removeAllElements();
	}
}