Re: Leopard, Snow Leopard & 32bit, 64bit Preferences

Yup, there's a CFBundleIdentifier.  I'll give the LSMinimumSystemVersionByArchitecture a shot, but I was trying to stay away deciding the logic based on OS version (from advice on this list).  My hope was that LSArchitecturePriority by itself would work, and the launcher would refuse to use the 32bit architecture on platforms where there was no 32bit Java (so that, if pigs started flying and a 32bit Java came out for 10.5, it would automagically work -- or if Apple removed 32bit support from 10.6, the app would continue to launch).  Is LSArchitecturePriority supposed to be doing what it's doing, or should it be recognizing the Java architecture support?

On Tue, Nov 3, 2009 at 1:50 PM, Mike Swingler <email@hidden> wrote:

On Nov 3, 2009, at 10:25 AM, Sam Berlin wrote:

> Folks,
>
> There was a discussion a while back on this list about 32bit & 64bit Java Preferences.  In summary, Snow Leopard supports 32 & 64bit Java, and Leopard supports 64bit Java only.  In our case, we want Snow Leopard to run 32bit (because we use native libraries that are only available in 32bit), but want Leopard to still run properly with 64bit Java (and we'll detect the architecture and not load the native libraries).  So we need our JavaApplicationStub to have both 32bit & 64bit slices (since we don't want to build & ship two different apps) and whichever is preferred will be used.
>
> Mike Swingler suggested that we use LSArchitecturePriority in the Info.plist (as opposed to the deprecated JVMArchs key in the Java element in Info.plist).  However, this does not seem to work right.
>
> The immediate issue we found was that altering the elements in LSArchitecturePriority in an existing Info.plist did nothing.  It was as if it the order of the items in it (or the existence of it at all) just didn't matter.  OTOH, right-clicking on the app and choosing whether to run in 32bit or 64bit mode did change the mode.
>
> Then we found that it seems like LSArchitecturePriority is being applied to new applications when they are installed.  (For example, after running the pkg installer, it accepted the priority in order of LSArchitecturePriority.)  However, the catch was that it was accepting the priority on Leopard too, even though there was no 32bit Java available.  When installing an app into Leopard with an LSArchitecturePriority that had i386 before x86_64, Java failed to start (giving an error message).
>
> It seems like the only reliable way to prefer 32bit & fall back to 64bit if 32 isn't available is to use the deprecated JVMArchs element.  Am I going about this the wrong way?

Does your app have a CFBundleIdentifier? Without one, LaunchServices can't reliably track it's settings for your app. I've also found that if LaunchServices is being flaky about picking up changes to the Info.plist, sometimes I can get it "unstuck" by moving that app to another directory, and moving it back.

To specify an OS to architecture minimum boundary, try adding a LSMinimumSystemVersionByArchitecture dictionary to your Info.plist. You can specify a minimum of i386=10.6.0, x86_64=10.5.0, and prioritize i386 above x86_64 with LSArchitecturePriority. Please see <http://developer.apple.com/Mac/library/releasenotes/Carbon/RN-LaunchServices/index.html> for more information about these two Info.plist keys.