/*
* Created on March 9, 2007
*
* Copyright (c) 2007 Jens Gulden
*
* http://www.frinika.com
*
* This file is part of Frinika.
*
* Frinika is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* Frinika 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 Frinika; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package com.frinika.sequencer.gui;
import java.util.Collection;
import java.util.HashSet;
/**
* Helps handling listeners.
* @author Jens Gulden
*/
public abstract class ListenerSupport<L, E> {
Collection<L> l;
/** Creates a new instance */
public ListenerSupport() {
l = new HashSet<L>();
}
public void addListener(L listener) {
l.add(listener);
}
public void removeListener(L listener) {
l.remove(listener);
}
public Collection<L> getListeners() {
return l;
}
/**
* Fire event to all.
*/
public void notifyListeners(E e) {
for (L listener : l) {
notify(listener, e);
}
}
/**
* Fire event to a single listener.
*/
public abstract void notify(L l, E e);
}