Programming Jakarta Struts is the basic that you need to understand and use Struts. Struts in Action (And the complete reference book) cointains more code samples. But you're required to understand how Struts works to some degree.
But both of them would fit nicely into your bookcase.
Hi, I would suggest you to first visit (www.coreservlet.com) website. This website contains pdf files which ou can download and read. These PDFs are great for beginners. I was also a beginner a week before but now I am got good understanding and implementation concepts. Hope that this will help you.