public void addNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback)
{
Logger logger = getLogger();
if (logger.isEnabledFor(Logger.TRACE)) logger.trace("Adding notification listener: " + listener + ", filter: " + filter + ", handback: " + handback + " to " + this);
if (listener == null) throw new IllegalArgumentException("Notification listener cannot be null");
// Normalize the arguments
if (filter == null) filter = NULL_FILTER;