I think you're asking a fair question.
When we designed the book, we chose to teach a person all the skills needed to design, code, and
test an e-commerce site. Since the book is meant for web beginners, we teach the basic web skills. However, we assume you already know Java.
Unlike other beginner books, we cover all the skills needed to design, code, and test a basic e-commerce site. That was the goal of the book. Although most books cover JSPs,
servlets, and sessions, most don't cover
JDBC, security, email, and custom tags. To write an e-commerce site, you need all of these components.
In addition, we believe the unique "paired pages" format is the best way to learn a subject. It's a methodical format that places all figures and examples of a single topic on the right-hand page, while the text that describes that topic is presented on the left-hand page.
Our book doesn't cover many advanced web programming topics, although we do introduce you to XML and EJBs. We designed the book this way. Once you finish our book, you'll be able to pick up an advanced web programming book and read it without any trouble.