Hi abu,
this is the wrong forum to ask for Java Certification.
You cannot take the developer exam without being a Java Certified Programmer (
SCJP Sun Java Certified Programmer), check
here for the certification path.
I doubt there is an efficient FREE online training program, what you need is
this book which you can buy new or used from amazon, or you can go to a public library, of Barnes & Noble and read it there while you sip a
coffee...
If you are REALLY new to Java
you should start with the basic stuff...I think you can find
Head First Java very useful.
When you feel ready for the certification (you can study on your own using those 2 books) you have to buy an exam voucher for $150,00 and then book the exam to the closest prometric centre.
During the preparation you can stop by here and you will find a lot of people ready to help you...I wrote here but I mean
here.
Good luck with your certification.
Giovanni