[Tutorials] How to Downgrade Java on a Mac

Update (Jan 31, 2013): This post has always been popular but today it got slammed. I won't point fingers (*applecoughoracle*) but I will say...what a cluster!@#$. So if you're here because your Java apps aren't running today, head on over to this Servoy forum thread where many people are doing a brilliant job of putting out information and fixes.

Why would you want to do this? Theoretically, never. Unfortunately, the latest Java update introduced a bug where the delete key removes two characters for the price of one. Hopefully they will release an update soon but since it has been a month or so now....

Instructions for v10.5.8 and v10.6.4

1 Recommend making a bootable backup before starting

2 Locate the required Java installers

     - Leopard: download update 5
     - Snow Leopard: grab your install DVD

3 Remove current installed java stuff (warning: no going back from this point on!). In terminal:

     sudo rm -R /Applications/Utilities/Java\ Preferences.app/
     sudo rm -R /System/Library/Frameworks/JavaVM.framework/
     sudo rm -R /System/Library/Java/
     sudo rm -R /System/Library/CoreServices/Jar\ Launcher.app
     sudo rm -R /System/Library/CoreServices/Java\ Web\ Start.app/
     sudo rm -R /System/Library/CoreServices/JavaVersion.plist
     sudo rm -R /System/Library/PrivateFrameworks/JavaApplicationLauncher.framework/
     sudo rm -R /System/Library/Frameworks/JavaEmbedding.framework/
     sudo rm -R /System/Library/CFMSupport/StubLibraries/JavaEmbeddingLib/

4.1 Reinstall java: Leopard

     - run the installer that you downloaded in step 1
     - restart

4.2 Reinstall java: Snow Leopard (haven't tested yet! but should work)

     - insert installer DVD
     - run terminal commands (change the paths in each command as necessary for both the OS X Install disc and your system hard drive):
          installer -verbose -pkg "/Volumes/Mac OS X Install Disk/System/Installation/Packages/Java.pkg -target /Volumes/Macintosh HD"
          installer -verbose -pkg "/Volumes/Mac OS X Install Disk/System/Installation/Packages/JavaTools.pkg -target /Volumes/Macintosh HD"
     - (alternately you can use a tool like Pacifist to browse for and run the Java.pkg and JavaTools.pkg installers located in the main .pkg installer)
     - restart

Note: we have confirmed this works for Leopard but haven't verified for Snow Leopard yet.