An EventBroker which administrates the listeners in a
java.util.WeakHashMap . This means
that such listeners can be garbage collected, even if they are still brokered.
author: Michiel Meeuwissen since: MMBase-1.8.5 version: $Id: WeakEventBroker.java,v 1.2 2007/07/26 14:08:53 michiel Exp $