I am intending to attempt the SCJD exams. I have passed the SCJP and have some good qualification in other languages however I am not as OO as I should be and I am under no illusions that I need to do a lot of study before I am ready to do the exams.
My question is whether to download the exam and do the study around the exam or to do the study without the distraction of the exam and then download it.
There will most likely be a sample assignment in the book.
On the other hand, I think it would be a good idea to get the SCJD assignment and then start to read up on the OO topic you have mentioned. You can always try to relate what you learn to the requirements of the assignment.