Upgrading java client from 6 u16 to 7 u55

We currently have EBS 12.1.3, and are using Java 6 u16 on the client to match other applications we have running in-house.  We have to match that specific version of java on our end-user clients for the other applications to work.  And now, we need to upgrade that version to v 7u55.  I was looking at note 1467892.1, but I am uncertain if I need to update both JDK and JRE to accomplish this, or just JRE (I think previously we just applied a JRE interoperability patch and downloaded the version of jre we needed, but not sure).  Probably a basic question, but although I can technically patch EBS, I'm not terribly familiar with the architecture when it relates to using java.  Any suggestions / advice would be appreciated, thanks.