There is no pre requisite for OCPJP
Oracle Certified Professional Java Programmer
This certification is for programmers experienced using the Java programming language. Achieving this certification provides clear evidence that a programmer understands the basic syntax and structure of the Java programming language and can create Java technology applications that run on server and desktop systems using J2SE 5.0.
To achieve this certification, candidates must successfully complete one exam. It is not necessary to be a Certified Java Associate prior to taking this exam.
Formerly Sun Certified Java Programmer (SCJP)