Hello Satish, welcome to Javaranch!
I did a quick search in this forum, the Bunkhouse Porch, and came up with a few threads on that topic.
Here's one to start with. You find some books mentioned in the
SCJP certification forum too. There's a bit of overlap between the 2 forums when it comes to the question "how do I prepare for this monster?".
Good luck and hope you'll be visiting the ranch often!
Pauline