Last October, Apple released Java Update 2012-006. This patch brought the Apple-provided JDK for OS X Lion v10.7 and OS X Mountain Lion v10.8 to version 1.6.0_37. At the same time, it disabled the Apple Java plugins and removed the Java Preferences panel that enabled users to manage the various Java releases on their computer.
On the Windows and Linux platforms, JDeveloper 11g R1 has been certified to run on Java 7 since patch set 5. This is not the case on OS X.
( The above is not a typo. Apple's OS for personal computer is now known as OS X; the « Mac » prefix has been dropped with the 10.8 release. And it's pronounced « Oh-Ess-Ten », by the way. Yes, I am a nitpicker. I know... )
Please note JDeveloper 11g R2 is not certified either. On any platform. It will generally work, but there are known issues with ADF Mobile. Personally, I would recommend to wait for 12c before going to JDK 7.
Now, suppose you have installed Oracle's JDK 7 on your Mac. JDeveloper will not run on it. It will even not install. Susan and I discovered this the hard way while setting up the ADF Mobile hands-on lab we ran at the UKOUG 2012 conference. The lab was a great success nevertheless, attracting nearly a hundred delegates. It was great to see the interest ADF Mobile already generates, especially among PL/SQL Developers and DBAs. But what did we do to make it work?
While Java Update 2012-006 removed the Java Preferences panel, it leaved in place OS X's command-line Java infrastructure. Thus, it is possible to invoke the Apple JDK 6 to start the JDeveloper installer. Suppose your user is named « Fred », and that the JDeveloper installer is on your desktop. You can execute the following command in a terminal window (on a single line) to start the installer:
/usr/libexec/java_home --version 1.6.0
--exec java -jar /Users/Fred/Desktop/jdevstudio11116install.jar
The JDeveloper installer, being provided a valid JDK reference, will set up the IDE and embedded WebLogic Server instance accordingly. Clever engineering at its finest!