Here's a hack that seems to restore the Cocoa-Java bridge on Snow Leopard. I have not tested it beyond a quick launch of one Cocoa-Java app. This is purely a data point that you can take for what it's worth. I offer no support and take no responsibility for what it may do to your system.
The trick is to copy two sets of files from a Leopard installation to the corresponding locations on the Snow Leopard installation:
- the com directory in /System/Library/Java, and
- the eight files ending with .dylib in /usr/lib/java (four of these are regular files, the other four are symlinks; if you prefer, you can copy just the files and recreate the symlinks by hand).
A coworker figured most of this out. I'm not even sure how he did it. We were originally experimenting with instructions from OneSwarm.org for downgrading to Java 1.5, but that seems not to be necessary to get the Java bridge back.
Obviously if you're a developer you can't ship this hack with your product, but it might allow you to upgrade to Snow Leopard sooner if the only dealbreaker was the absence of the Java bridge.