I bought this book mainly because of the O'Reilly name. But it didn't help me understand the technology completely. It is a good and detailed, no nonsense, like all the O'Reilly titles. But I just felt that I was reading the spec while going through this book. I think it lacked explanations on why you would use certain things and why you wouldn't.
For example, I was a bit disappointed with the chapters on Entity beans and Transactions because all I got what these are the specs and here's how to program it, but no explanation on what are the issues pertaining to use these and what limitations, lessons learned, cool tricks to shed light more light on this.
In summary, I've read Monson-Haefel, Ed Roman's Mastering EJB (Wiley), and Tom Valesky's EJB book (Addison-Wesley). Althoug I usually stick with O'reilly, but right now, I would have to recommend Roman's EJB book as the most insightful and practical.
Recommended:
