JComponent comp = (JComponent) e.nextElement();
JComponent comp = (JComponent) i.next();
  public void validateInvalidComponents()  {    for (Enumeration e = invalidComponents.elements(); e.hasMoreElements(); )      {        JComponent comp = (JComponent) e.nextElement();        if (! (comp.isVisible() && comp.isShowing()))          continue;        comp.validate();      }    invalidComponents.clear();  }