Hi Rahul:
The books that you have are more than sufficient to cover all the study matter. I would advise that you stick to one-book as your principle soure (I chose Simon Roberts...et-al) and do the exercises and the problems from the other book if you have the time.
Khalid Mughal is an excellent book too; but it explains everything in a lot more detail. However, there are certain topics which
you should study from Khalid Mughal also as the Simon Roberts is not sufficient. These topics are inner-classes and io.
As far as how time u need to prepare....I guess if you have gone through the Simon Roberts book a couple of times thoroughly; you should be in a pretty good shape to take the
test.
Hope the above helps.
Fazal
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