/* This file is part of the db4o object database http://www.db4o.com Copyright (C) 2004 - 2011 Versant Corporation http://www.versant.com db4o is free software; you can redistribute it and/or modify it under the terms of version 3 of the GNU General Public License as published by the Free Software Foundation. db4o is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/. */ package com.db4o.foundation; /** * @exclude */ public class ListenerRegistry <E>{ public static <E> ListenerRegistry<E> newInstance() { return new ListenerRegistry<E>(); } private IdentitySet4 _listeners; public void register(Listener4<E> listener){ if(_listeners == null){ _listeners = new IdentitySet4(); } _listeners.add(listener); } public void notifyListeners(E event){ if(_listeners == null){ return; } Iterator4 i = _listeners.iterator(); while(i.moveNext()){ ((Listener4)i.current()).onEvent(event); } } public void remove(Listener4<E> listener) { if (_listeners == null) { return; } _listeners.remove(listener); } }