Just Completed my Oracle Certified Professional,
Java 6 Programmer certification with an 86% after about 3 months of solid preparation and 3 months of on/off preparation.
For studying I used the
Sierra/Bates Study Guide and
Mock Exam books as well as the
Sybex SCJP6 book as an additional reference.
For Mock Exams I completed the following:
Oracle ePractice Exam 1 - 86%
Oracle ePractice Exam 2 - 89%
MasterExam Quiz A - 70%
MasterExam Quiz B - 68%
Sierra/Bates Mock 1 - 71%
Sierra/Bates Mock 2 - 78%
Sierra/Bates Mock 3 - 73%
Sierra/Bates Mock 4 - 73%
The Oracle ePractice Exams are the closest to the actual difficulty of the real exam.
I also wrote around 150 small sample programs to demonstrate concepts, did all of the exercises in the Mock Exam book, all of the self-tests, and created around 500 Flash
cards.