public static boolean hasOneInheritor(final PsiClass aClass) {
    final CountingProcessor processor = new CountingProcessor(2);
    ProgressManager.getInstance().runProcess(
      (Runnable)() -> ClassInheritorsSearch.search(aClass, aClass.getUseScope(), false).forEach(processor), null);
    return processor.getCount() == 1;
  }
public static boolean hasOneInheritor(final PsiClass aClass)