EventFactory.java

/*
 * Dog - Core
 * 
 * Copyright (c) 2013 Dario Bonino, Luigi De Russis and Luca Semprini
 * 
 * Licensed 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 it.polito.elite.dog.core.library.util;

import java.util.HashMap;

import org.osgi.service.event.Event;
import org.osgi.service.event.EventConstants;

import it.polito.elite.dog.core.library.model.notification.Notification;
import it.polito.elite.dog.core.library.model.notification.core.MonitorNotification;

/**
 * This class helps to create Event. It hosts some static methods that
 * allow generating an Event with simpler code writing.
 * 
 * @author <a href="mailto:dario.bonino@polito.it">Dario Bonino</a>
 * @author <a href="mailto:luigi.derussis@polito.it">Luigi De Russis</a>
 * @author Luca Semprini
 * @see <a href="http://elite.polito.it">http://elite.polito.it</a>
 * 
 */
public class EventFactory{
	

	/**
	 * Factory for creating a general event
	 * @param notification to convert
	 * @param bundleSymbolicName name of the bundle that create the Event
	 * @return the event to send
	 */
	public static Event createEvent(Notification notification, String bundleSymbolicName){
		HashMap<String, Object> eventProp = new HashMap<String, Object>();
		
		// Add the event topic
		eventProp.put(EventConstants.EVENT_TOPIC, notification.getNotificationTopic());
		// Insert the bundle name inside the event properties (OSGi Event Admin Service Specification 1.3)
		eventProp.put(EventConstants.BUNDLE_SYMBOLICNAME, bundleSymbolicName);
		// Add the whole Notification to the Event (OSGi Event Admin Service Specification 1.3)
		eventProp.put(EventConstants.EVENT, notification);
		
		Event modifiedEvent = new Event(notification.getNotificationTopic(), eventProp);
		return modifiedEvent;
	}
	
	/**
	 * Create a MonitorEvent for sending MonitorNotification from DogScheduler to other bundles
	 * @param notification to convert
	 * @param bundleSymbolicName name of the bundle that create the Event
	 * @return the event to send
	 */
	public static Event createMonitorEvent(MonitorNotification notification, String bundleSymbolicName){
		HashMap<String, Object> eventProp = new HashMap<String, Object>();
		
		// Add the event topic
		eventProp.put(EventConstants.EVENT_TOPIC, notification.getNotificationTopic());
		// Add the listener of the MonitorNotification if any (OSGi Monitor Admin Service Specification 1.0)
		if (notification.getListener()!=null){
			eventProp.put("mon.listener.id", notification.getListener());
		}
		// Insert the bundle name inside the event properties (OSGi Event Admin Service Specification 1.3)
		eventProp.put(EventConstants.BUNDLE_SYMBOLICNAME, bundleSymbolicName);
		
		// Add the whole MonitorNotification to the Event (OSGi Event Admin Service Specification 1.3)
		eventProp.put(EventConstants.EVENT, notification);
		
		Event modifiedEvent = new Event(notification.getNotificationTopic(), eventProp);
		return modifiedEvent;
	}	
}