Disable Java Auto Update Prompt for 1.7u25 on Mountain Lion
Open a Terminal and execute:

sudo defaults write /Library/Preferences/com.oracle.java.Java-Updater JavaAutoUpdateEnabled -bool false


Source: https://jamfnation.jamfsoftware.com/discussion.html?id=6489

Update:  This answer has been confirmed to work on OS X 10.11.5 (El Capitan)