In JDK-8306112, user-defined anchors was added to the hidden classes description in Class specification. Currently, the Class::isHidden API does not describe what a hidden class is, but links to defineHiddenClass which describes the specification of hidden class definition, including its behaviors as a class, in detail. We should link to the "Hidden Classes" section for a brief overview of hidden classes in Class::isHidden specification.

I don't think we need such a link in defineHiddenClass, for the contents of that section is already completely covered in that method's specification.