Hi Bruce. I agree with your point that it's necessary to automate testing for a larger application. I'm not sure if this book is the best place to show how to do that. I will look into it. If it's possible to show how to do that without using too many pages, then I would like to add some coverage of a tool like JUnit in the next edition. Otherwise, it might be best to leave this to a separate book such as the one Jeanne suggested.
Coincidentally, I am currently working on upgrading
Murach's Java Programming from Java SE 7 to Java SE 8, and we are planning on adding some coverage of JUnit to that book. If that goes well, we may add similar coverage to the next edition of the servlet/JSP book.
Thanks!