Informatica Power Center is normally packaged with Java version. You don't need to install the same separately.
If the customer has purchased OBIA ,it should include Informatica as well. Please check. General procedure is to raise a shipping case with informatica if you dont have the software from informatica.
Since Informatica 9.6.1HF3 services on AIX is certified with JDK version 22.214.171.124
(build pap6470_27sr2fp10ifix-20150313_01(SR2 FP10+IV70681)),
You have to install it separatly. In your .profile you must point the Infa variables to this installation.
It shows like this:
The original question was about Oracle Enterprise Linux (which is a version of RedHat Enterprise Linux), not about AIX.
Nonetheless Gunther has raised a good point to note: on AIX, HP-UX, and zLinux (if I recall correctly) it is mandatory to install one particular JDK version on the server before installing the Informatica platform software; on Windows, Linux, and Solaris it is mandatory to use the JDK version installed with the platform.
In this case it means that on Oracle Enterprise Linux the installer will install one particular JDK, and this JDK has to be used with the Informatica platform; messing up this JDK installation is a good way to ruin your whole software installation.