Hi there, yesterday I passed the exam for the SCJP2. I'd like to thank the javaranch people for their support, especially Desai Sandeep, Cindy Glass, Scott Appleton, Jon Miller who answered directly to my topics. For preparation I used JWhiz and JCertify. In JWhiz' Final test I made over 90 percent and the result of the real exam was very close to this. My advice for preparing the SCJP2 exam is therefore as follows: (1) Do the JWhiz Practice tests and generalize the subject of each question. I.e. if there is a question about the meaning of 'new TextField(10)', check out all the constructors of the class TextField and ask yourself what could be questions of the same type (i.e. Constructors for Button, Canvas, Checkbox, Choice, Label, List, and Scrollbar). Or if there is a question about which of the following is a correct chaining of io objects, just work out what in io can be chained and why. (2) If somethings unclear to you, just do a little programming to check it out. That helps a lot.
If you do so, then you'll get better each time you do one more of the nine JWhiz Practice Tests and in the real exam you'll be as successful as in the JWhiz' Final test.