https://github.com/hiredman/javap-mode.git
git clone 'git://github.com/hiredman/javap-mode.git'
load the mode, it hooks file loading, so when you load a .class file you get the javap output. syntax hilighting of the javap output is a work in progress.
better hilighting would be nice, also some way to step though varying levels of verbosity of javap output
would be nice to hit enter on line in line number table and jump to the line in the method's bytecode