Informatica Cloud now supports Java 8. You'll need to uninstall and download the latest agent from the 'agent download' in Informatica Cloud in order to get the Java 8 version of the agent. All upgraded agents were upgraded to the Java 7 version.
If you are interested, or have the requirement to use Java 8, please refer to the following Yonyx with step by step instructions: 498429
The default agent available before Summer' 16 upgrade uses Java 7, and was not updated to Java 8 during the upgrade. The migration to Java 8 needs to be performed by the user. If you download a new agent from Informatica Cloud, it uses Java 8.
Java 8 agents allows better performance when it comes metadata fetch by avoiding the use of the legacy ODBC-JDBC bridge. Java 8 also supports TLS encryption by default.