code: protected static RuntimeException unsettable(String view, String attribute, boolean create) {
      // This matches the behavior of the real file system implementations: if the attempt to set the
      // attribute is being made during file creation, throw UOE even though the attribute is one
      // that cannot be set under any circumstances
      checkNotCreate(view, attribute, create);
      throw new IllegalArgumentException("cannot set attribute '" + view + ":" + attribute + "'");
    }
docs: Throws a runtime exception indicating that the given attribute cannot be set.