private void handleAddCategoryDefinition() {
   String name =
       NLS.bind(
           PDEUIMessages.CategorySection_newCategoryName, Integer.toString(++newCategoryCounter));
   while (categoryExists(name)) {
     name =
         NLS.bind(
             PDEUIMessages.CategorySection_newCategoryName,
             Integer.toString(++newCategoryCounter));
   }
   String label =
       NLS.bind(
           PDEUIMessages.CategorySection_newCategoryLabel, Integer.toString(newCategoryCounter));
   ISiteCategoryDefinition categoryDef = fModel.getFactory().createCategoryDefinition();
   try {
     categoryDef.setName(name);
     categoryDef.setLabel(label);
     fModel.getSite().addCategoryDefinitions(new ISiteCategoryDefinition[] {categoryDef});
   } catch (CoreException e) {
     PDEPlugin.logException(e);
   }
   fCategoryViewer.setSelection(new StructuredSelection(categoryDef), true);
 }