time effort for Oracle Certified Associate, Java SE 7 Programmer 1Z0-803

I have no previous knowledge in Java. My only programming skills is Oracle SQL (passed 1Z0-051 SQL Fundamentals I).
What's the time effort for passing Oracle Certified Associate, Java SE 7 Programmer 1Z0-803? From zero to exam?
What's the time effort for passing Oracle Certified Associate, Java SE 7 Programmer 1Z0-803? From zero to exam?

Comments
Thanks for the hint about Head First Java.
I approve this! I was preparing 3 years for Oracle SQL exam. I had quite a lot practise expirence in workplace and learned about 6 hours / month.
That's why I am interested how much time for preparation. Because have kids and can't learn 4h a day
I spent around four weeks not studying every single day but 1-3 hrs on most days, however, I had been programming for sometime. One way to tell is by using the enthuware practice exam (I used it). It is harder than the real exam, when you get to the point that you are passing that with 90% plus you are definitely ready.
I second Head First Design patterns. It is a really good book. I actually just recently finished it