I followed the K&B book only. That is more than enough if you already know Java to some extent. Otherwise u need a intro to Java. Core Java2 will do that. And do all the exercises and review questions given in K&B. The real exam will have the same level of complexity as that of K&B review questions. Dont forget to take the Dan's Questions and K&B Mock exam on the CD.I got the same marks in the real exam that I got in K&B Mock. All the best.
Hi You would need to read the the book by Khalid Mughal and/or Kathy and Bert thoroughly. These books shall help you prepare well. And the level of difficulty is similar to the K&B mock exam and the Enthuware.com JQPlus mock exams.