I am using a book by Bruce Eckel, the free electronic Java book. Is it good enough and is there any other book that I woould need to read. Also can someone tell me the best websites that have mock exams for Java1.4. I have gone through Marcus Green's mock exams, they are very good but I want to try a lot more.
You can see a list of Mock exams here. I'm not sure which book you have. I would recommend getting a book specifically geared toward the Certification exam -- I'm a huge fan of Kathy and Bert's certification book Check out my review in the bunkhouse.
I loved A Progammer's Guide to Java Certification though I don't believe it's been updated for 1.4. I think this is a matter of taste though and some may find it too academic/theoretical. I've passed my SJCP for 1.2 using that book primarily but I've heard such good things about the Kathy Sierra book that I also picked that up, just to solidify what I already know and so that I can take the 1.4 upgrade exam at some point off in the distance.