I suspect it is the Head First
JSP and
Servlets book. There are two versions one for the 1.4 and one for the 1.5 versions of the exam. Although the objectives of the two exams are the same they have refined the material to better reflect the contents of the real exam (plus a few foreach loops I suspect).
The exam in the book is reputed to be a very good guide to being ready for the real exam.