Welcome bansal prakash,
Learning java is just like learning sex swimming ....
You can read a lot about it, but it aint going to help until you start doing it practically.
install java in your pc, ensure its working with PATH etc. set.
Dont just read the programs, actually type them out and make them work,
you will be surprised to number of mistakes you will find in your code.
As for books to refer, my friends here have suggested good ones.
(call me old fashioned), but I prefer to have a hard copy as compared to an e-book.