private void showHelp() {
    JDialog dialog = new JDialog(this, resources.getString("dialog.help.title"));
    final JEditorPane helpText = new JEditorPane();
    try {
        URL url = getClass().getResource("GridWorldHelp.html");
        
        helpText.setPage(url);
    } catch (Exception e) {
        helpText.setText(resources.getString("dialog.help.error"));
    }
    helpText.setEditable(false);
    helpText.addHyperlinkListener(new HyperlinkListener() {
        public void hyperlinkUpdate(HyperlinkEvent ev) {
            if (ev.getEventType() == HyperlinkEvent.EventType.ACTIVATED)
                try {
                    helpText.setPage(ev.getURL());
                } catch (Exception ex) {}
        }
    });
    JScrollPane sp = new JScrollPane(helpText);
    sp.setPreferredSize(new Dimension(650, 500));
    dialog.getContentPane().add(sp);
    dialog.setLocation(getX() + getWidth() - 200, getY() + 50);
    dialog.pack();
    dialog.setVisible(true);
}