Kindly suggest me .. How to start Java Study , How I Can learn Quickly? I Have programming back ground in C/C++ with sound knowledge
For a quick learn, I'd suggest buying the Headfirst Java book. Granted, it has a lot of details on each section, which would help you become more familiarized with the language, but if learning quickly is what most important to you, you can simply skim on each topic, and try making your own little programs. For example, when you read about inheritance, and how in Java you create a subclass and parent class, quickly go ahead and try doing that yourself. I think your knowledge on C/C++ would also help you with creating these little programs and identifying similarities and differences.
Now, this is all about learning Java - as a language. If you wish to take a step ahead and face the SCJP/OCPJP exam, you will also have to learn the details, those 'gotcha' parts you encounter!