/**
  * Produces a ChartingPropertyInspector which tracks property number index from the given
  * properties list, stored in the provided parent frame, and applied in the given simulation. This
  * constructor will give the user a chance to cancel the construction, in which case
  * validInspector will be set to false, and generator may be set to null. In that case, assume
  * that the inspector will be deleted immediately after.
  */
 public ChartingPropertyInspector(
     Properties properties, int index, Frame parent, final GUIState simulation) {
   super(properties, index, parent, simulation);
   generator = chartToUse(properties.getName(index), parent, simulation);
   globalAttributes =
       findGlobalAttributes(); // so we share timer information.  If null, we're in trouble.
   validInspector = (generator != null);
 }