I agree that 1-2 months is probably a good starting estimate for how long it will take. What your experience is will depend on how familiar you are with the topics covered by the objectives. For example, most of my Java programming experience was in a multithreaded application, so I already knew most of that material, but I had to spend more time on Collections and Wrapper classes because I was less familiar with those.
I would suggest getting a good book that covers the exam objectives. The exam tests for a lot of knowledge I consider esoteric, so you can't count on your experience alone. For example, I had no idea you could override a method to have a higher visibility. The Kathy Sierra/Bert Bates book is very good, and since Kathy wrote a lot of the questions on the
test she is very good at explaining just what kind of things you'll need to know. I also got a lot out of the Mughal/Rasmussen book, although I suspect those authors erred by including too much material.
Finally, I want to echo the advice about mock exams. I learned a lot just by getting answers wrong on those exams, and thinking about them until I realized why my answer was incorrect.
Good luck!
Robert
SCJP 1.4
