private void fill(Operator root) {
   int numTotal = root.getProcess().getRootOperator().getErrorList().size();
   errors = root.getErrorList();
   String errorString;
   switch (errors.size()) {
     case 0:
       errorString = "No problems found";
       break;
     case 1:
       errorString = "One potential problem";
       break;
     default:
       errorString = errors.size() + " potential problems";
       break;
   }
   if (errors.size() != numTotal) {
     errorString = errorString + " (" + (numTotal - errors.size()) + " Filtered)";
   }
   headerLabel.setText(errorString);
   model.fireTableDataChanged();
 }