Get the book that shows you not only what to study, but "how" to study. The only classroom-based integrated study system for professional certification gives you complete coverage of all objectives for the Sun Certified Programmer for Java 5 exam, hundreds of practice exam questions, and hands-on exercises. The CD-ROM features full practice exam software plus an adaptive test engine.
I don't think such a book fits Java beginners. This one MUST be read in two cases : 1 - You're preparing for the SCJP exam (You'll find every single detail included in the exam there)
2 - You want to know exactly how java works. I mean by "exactly" every single detail about all the basic things : literals, extending, implementing, exceptions, serialization, overriding, autoboxing and autounboxing.. You know, all the cases you would meet while you code, all the combinations. And I didn't see any other book with such fineness.
Besides, Kathy Sierra make it funny to get all that, and that's what made the book a success.
This book does have some interesting tips and viewpoints. For example it connects things that you might have said beforehand "ok, well that made sense before" to actual rules that can be applied to broader questions. The problem with this book though is that it seems like it is geared towards someone with little or no Java experience.
It did however do a good job of explaining rules and ideas behind generics, but then again, most of the question difficulty lies in finding the trickiness in the question as opposed to the question being about 'is this valid or a good idea'.
It may be tempting to give this book a bad review simply because the SCJP sucks, but this is actually a useful book. Also, I think Kathy Sierra is one of the better tech writers around, and the book is quite readable.
The information in this book is not very useful outside the exam. The exam is pointless therefore the book is pointless. The book is required to pass the exam.