if (preferencesService == null) { registerServices();  return bundleContext.getService(reference); } return null;
registerServices();  return bundleContext.getService(reference);
	public synchronized Object addingService(ServiceReference reference) {		if (preferencesService == null) {			registerServices();			//return the registry service so we track it			return bundleContext.getService(reference);		}		return null;	}