I had to look up what a Btech was. Interesting.
Anyway, it really depends on what you want to do. Getting a Java certification certainly can't hurt, but it's going to be secondary to any actual work you've done. Getting a master's degree can't hurt either, but it might be overkill if you want to be an entry-level programmer (and hey, you can always try to get your job to pay for a master's instead of paying for it yourself before you start working).
I would say that the best thing you can do is to actually program. Program in your spare time. Make some games, or little programs you can use in your own life. Throw them together as a portfolio. Then you'll have coding experience and something you can point to and say "here's what I can do", which is going to be more impressive than a certificate.