Thank you for your suggestion and sorry of my
thread wasn't easily accessible for those without the book. I'm logging documentation defects as requested:
https://www.selikoff.net/ocp11-1/. This particular thread specifically deals with the answer to question 3 of chapter 1.
As you can see from the screen shot single-file source code executions work with both JDK and user defined classes. You need to know this for the certification exam. I hope this helps.