Want to see java part of "IL-2 Sturmovik"?
Then just do it. You can use these tools to dump and study java classes.
Class dumper for Rus release
Class dumper for Eng release
To see java source code you can use Jad decompiler by Pavel Kouznetsov.

Also, if you havn't got IL-2 Sturmovik, or just don't want to download and run any binaries(smart enough), go here and get packed java sources of IL-2.

Update 16.09.2004: I didn't test it with FB, but someone already did it with FB/AEP(SimHQ.com forum).
Repacked and made available of java sources, which dumper could put hand on(ClassLoader-s you know;)

Update 30.03.2006: Added DoItYourself(still in pogress) description on how to do it from scratch

Any questions: [email protected]