public void addConstructors(JMenu menu, Collection<Class> classes)
    {
        boolean first = true;
        Iterator<Class> iter = classes.iterator();
        while (iter.hasNext())
        {
            if (first)
                first = false;
            else
                menu.addSeparator();
            Class cl = iter.next();
            Constructor[] cons = cl.getConstructors();
            for (int i = 0; i < cons.length; i++)
            {
                menu.add(new GridConstructorItem(cons[i]));
            }
        }
    }