@NotNull
  @Override
  protected String getNotFoundMessage(@NotNull Project project, @NotNull Editor editor, @NotNull PsiFile file) {
    final PsiMember source = findSource(editor, file);
    if (source instanceof PsiClass) {
      return GroovyBundle.message("no.super.classes.found");
    }
    else if (source instanceof PsiMethod || source instanceof GrField) {
      return GroovyBundle.message("no.super.method.found");
    }
    else {
      throw new IncorrectOperationException("incorrect element is found: " + (source == null ? "null" : source.getClass().getCanonicalName()));
    }
  }
@NotNull
  @Override
  protected String getNotFoundMessage(@NotNull Project project, @NotNull Editor editor, @NotNull PsiFile file)