I\'ve instaled the Java for Developer package provided from Apple for 10.7 and java apps are running fine
but eclipse cannot find the JDK root path and I cant either
I have just ran into the same problem after updating. The JRE that is downloaded by OSX Lion is missing JavaRuntimeSupport.jar which will work but can wreck havoc on a lot of things. If you've updated, and you had a working JDK/JRE installed prior to that, do the following in Eclipse:
1) Project > Properties > Java Build Path > Select broken JRE/JDK > Edit
2) Select "Alternate JRE"
3) Click "Installed JREs..."
4) In the window that opens, click "Search..."
If all goes well, it will find your older JRE/JDK. Mine was in this location:
/System/Library/Frameworks/JavaVM.framework/Versions/1.6/Home