Thanks to the advices in this forum. I only used the book of Kathy Sierra and Bert Bates (a great test book, indeed!) and read it twice for about 3 weeks before I took the exam today. The score is 72% (fine for me). On the hindsight, I consider the exam is very exam oriented and the questions are highly irrelevant to real world scenario, as a 5-year Java goer. That said, preparing the exam did fortify my Java knowledge foundation. So still, I am satisfied with what I have done so far. Good luck to all near the exams.