I was good in Java and I have nearly worked with all of their technologies starting from plain command line java applications, applets to advanced servlets, EJB's etc. Recently I decided to appear for the Sun Java cetification exam. Till now, I had never concentrated on understanding the complex underlying difficulties(I mean the basics) in java such as to why certain compiler errors occur and stuffs like the range of primitive data types and all those sort of things. Especially, Threads, I never liked them even a single bit. But as it seems, they turn out to be the bulk of questions in the exam. So, I had to collect some preparatory materials to get myself back at the basics again. To my amusement, I have nearly gone thru all of them in a couple of days and I only have a final revision probably before the day of the exam. They are easy except that you got to understand certain concepts to the core. Those things can be achieved by attending number of mock exams and understanding why certain answers are like they are. Concepts are the major things that form the part of any question. I have tried a number of mock exams and seem to just pass them thru.But I do believe that the actual exam would be far easy than what I had to go thru here. I'm confident of clearing it at ease.
For persons starting to prepare for the exam, I will advise to take notes of each concept that you come across in a notepad as points. These notes can later be used to handle problems based on those concepts. Further you can only concentrate on these concepts before the exam.
Try attending as many number of mock exams as you can, to make sure you are upto the toughest level, so that you can clear the actual exam easily. I would like you guys to visit the following link:-
This link contains links to all mock exams for java on the net. You can daily attend 2 or 3 exams to check out your status. Well the most important thing that has to be taken note of is the time management. You have just 70+ and most of them are choose or drag and drop type and there is 2:30 hours. So make sure you manage your time well in the exam. At home, you might be able to complete all the questions in an hour. But make sure that you take your time in the exam. In addition, I got the following materials that could help you. Regarding study guides, you can go for the McgrawHill java 2 certification complete guide. And for the exams, you can purchase exams from troytec.com, testkiller.com, certkiller.com. They update their questions on a regular basis.
Following are some mock exams that can help you:-
MockExam1 MockExam2 MockExam3
All the Best!!!!!!!! for the exam and do reply on how you felt the exam. Please reply to me with e-mail for further materials.