/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2002 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.netbeans.modules.web.dd.wizards;

import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import javax.swing.JPanel;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import org.openide.util.HelpCtx; 

abstract class BaseWizardPanel extends JPanel { 

    private final Set listeners = new HashSet(1); // Set
    
    private static final long serialVersionUID = -2938499199217476217L;
    
    public final void addChangeListener(ChangeListener l) {
        synchronized(listeners) {
            listeners.add(l);
        }
    }
    public final void removeChangeListener(ChangeListener l) {
        synchronized(listeners) {
            listeners.remove(l);
        }
    }
    protected final void fireChangeEvent() {
        Iterator it;
        synchronized(listeners) {
            it = new HashSet(listeners).iterator();
        }
        ChangeEvent ev = new ChangeEvent(this);
        while (it.hasNext()) {
            ((ChangeListener)it.next()).stateChanged (ev);
        }
    }
    abstract void setData(); 
    abstract HelpCtx getHelp(); 
}