upnp/extra/src/main/java/org/apache/felix/upnp/extra/util/UPnPSubscriber.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.extra.util;

import java.util.Dictionary;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;

import org.osgi.framework.BundleContext;
import org.osgi.framework.Filter;
import org.osgi.framework.ServiceRegistration;
import org.osgi.service.upnp.UPnPDevice;
import org.osgi.service.upnp.UPnPEventListener;
import org.osgi.service.upnp.UPnPService;

/* 
* @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a>
*/
public class UPnPSubscriber {
	private BundleContext context;
	private UPnPEventListener listener;
	private HashMap hash;
	
	private class Subscription implements UPnPEventListener{
	    ServiceRegistration registration;
	    
	    Subscription(String keys){
	 		try {
				Filter filter = context.createFilter(keys);
				Properties props = new Properties();
				props.put(UPnPEventListener.UPNP_FILTER, filter);
				registration = context.registerService(UPnPEventListener.class.getName(), this, props);
			}catch (Exception ex){
				System.out.println(ex);
			}
	    }
	    
	    public void unsubscribe(){
			registration.unregister();
	    }
	    
        public void notifyUPnPEvent(String arg0, String arg1, Dictionary arg2) {
            listener.notifyUPnPEvent( arg0,  arg1,  arg2);
        }
	}
	
	
	public UPnPSubscriber(BundleContext context,UPnPEventListener listener){
	    if ((context == null)|| (listener == null))
	        throw new IllegalArgumentException("Illegal arguments in UPnPSubscriber constructor.");
		this.context = context;
		this.listener = listener;
		hash = new HashMap();
	}

	public void subscribe(String filter){
		if (hash.get(filter) == null){
		    hash.put(filter, new Subscription(filter));
		}	
	}
	
	public void unsubscribe(String filter){
		if (hash.containsKey(filter)) {
		    Subscription subscription = (Subscription) hash.get(filter);
		    subscription.unsubscribe();
			hash.remove(filter);
		}
	}
	
	public void unsubscribeAll(){
	    Iterator list = hash.entrySet().iterator();
	    while (list.hasNext()){		        
	        Map.Entry entry = (Map.Entry) list.next();
	        Subscription subcription = (Subscription) entry.getValue();
	        subcription.unsubscribe();
		    list.remove();
	    }
	}

	public String subscribeServiceIdOf(String deviceId, String serviceId){
		String keys = "(&(" + UPnPDevice.ID + "="+ deviceId + ")(" + UPnPService.ID + "=" + serviceId + "))";
		subscribe(keys);
		return keys;
	}
	
	public String subscribeServiceTypeOf(String deviceId, String serviceType){
		String keys = "(&(" + UPnPDevice.ID + "="+ deviceId + ")(" + UPnPService.TYPE + "=" + serviceType + "))";
		subscribe(keys);
		return keys;
	}
	
	public String subscribeEveryServiceType(String deviceType, String serviceType){
		String keys = "(&(" + UPnPDevice.TYPE + "="+ deviceType + ")(" + UPnPService.TYPE + "=" + serviceType + "))";
		subscribe(keys);
		return keys;
	}
	
	public String subscribeAllServicesOf(String deviceId){
		String keys = "(" + UPnPDevice.ID + "="+ deviceId + ")";
		subscribe(keys);
		return keys;
	}
	
	public String subscribeEveryDeviceTypeServices(String deviceType){
		String keys = "(" + UPnPDevice.TYPE + "="+ deviceType + ")";
		subscribe(keys);
		return keys;
	}
	
	
	public void unsubscribeServiceIdOf(String deviceId, String serviceId){
		String keys = "(&(" + UPnPDevice.ID + "="+ deviceId + ")(" + UPnPService.ID + "=" + serviceId + "))";
		unsubscribe(keys);
	}
	
	public void unsubscribeAllServicesOf(String deviceId){
		String keys = "(" + UPnPDevice.ID + "="+ deviceId + ")";
		unsubscribe(keys);
	}
}