When we developed "Murach's
Java Servlets and JSP", we used version 4.0 of
Tomcat, which uses the 1.2
JSP specification, to develop and
test all examples in the book. We didn't cover all the differences between the 1.1 and 1.2 specs because we thought it would be better to focus the book on teaching the 1.2 spec to someone who is new to servlet and JSP development.
Ever since we started developing books here at Mike Murach & Associates, our goal has always been to develop each chapter within a book as an independent module. That way, you can read the chapters in a book in the order you want, skipping the chapters that you don't need. Plus, this makes the structure of the book easier to understand, which makes it easier to find the information you're looking for. In practice, it isn't always possible to completely modularize each chapter, but we always try to limit the amount of "chaining" between examples.
In this book, that lead to many short and independent applications in the first 16 chapters of the book that illustrate key servlet and JSP skills. That's why we decided to present a more complete application (in this case, an online store) in the last four chapters of the book that shows how the applications presented in the first 16 chapters of the book can fit together to form a larger application.