@Override
    public void visitClass(@NotNull PsiClass aClass) {
      if (!aClass.isInterface() || aClass.isAnnotationType()) {
        return;
      }
      final PsiField[] fields = aClass.getFields();
      if (fields.length != 0) {
        return;
      }
      final PsiMethod[] methods = aClass.getMethods();
      if (methods.length != 0) {
        return;
      }
      final PsiReferenceList extendsList = aClass.getExtendsList();
      if (extendsList != null) {
        final PsiJavaCodeReferenceElement[] referenceElements = extendsList.getReferenceElements();
        if (referenceElements.length > 0) {
          if (referenceElements.length > 1) {
            return;
          }
          final PsiReferenceParameterList parameterList = referenceElements[0].getParameterList();
          if (parameterList == null) {
            return;
          }
          final PsiTypeElement[] typeParameterElements = parameterList.getTypeParameterElements();
          if (typeParameterElements.length != 0) {
            return;
          }
        }
      }
      registerClassError(aClass);
    }
@Override
    public void visitClass(@NotNull PsiClass aClass)