Nashorn user's guide https://docs.oracle.com/javase/8/docs/technotes/guides/scripting/nashorn/api.html#classfilter_introduction

points to invalid URL

https://docs.oracle.com/javase/8/docs/jdk/api/nashorn/jdk/api/scripting/ClassFilter.html

The above should be

https://docs.oracle.com/javase/8/docs/jdk/api/nashorn/jdk/nashorn/api/scripting/ClassFilter.html

You can check it by clicking on the hyperlink from user's guide to get 404.