Kathy Sierra and Bert Bates' book is the best by general concensus :)
http://www.amazon.com/exec/obidos/ASIN/0072226846
I used nothing else (well, several years of professional experience can't hurt).
From what I've heard about ucertify their product isn't very good. Certainly not good enough to justify the money spent on it.
Exam cram books are useless, they don't teach you what you need to know in any way that sticks (and you do want to retain that knowledge now do you?).
I've read an earlier version and while nicely written there are better books out there (see above).
I've also read an earlier edition of the other book cheenu mentions, and it's nice. But it's not up there with Kathy's book.
Of course you also need a copy of the Java Language specification, which you can get online from Sun, and a copy of the Java API documentation similarly straight from Sun.
Both are also available in bookform if you prefer dead trees.
jwenting
duckman
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Be prepared to take some time on it. The book by Kathy and Bert took me a LONG time to read! Not that I'm a slow reader, but you just can't zip through something that packed with information. I still don't think I'm ready for it. I've read some parts of the book twice but I've never took any of the practice exams and that's an important part.
server_crash
Postaholic
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I went through the entire book 3 times, did the practice questions the third time around and kept revising until I got them all right.
Took the exam and was done with nearly an hour left. Scored 85%.
Might have scored higher had I gone through my answers yet another time but from experience I know that's usually counterproductive as you begin to doubt things you got right the first time around.
Indeed, take LOTS of time studying for the exam. You may also want to defer the exam until you can go for the new 5.0 exam for which there is as of yet no good study material available (it's too new).
If you think a mock exam, any mock exam, is too hard you're not ready!
jwenting
duckman
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