I know the Army makes you do boot camp, while the AF has a more relaxed office training.
Eh, I'm not sure you can call what the Army does "boot camp." There is a 12 day orientation, JAG School, and two months of "Officer's Basic."
And you'll probably get something more or less like that everywhere.
Does JAG do OCS in the AF?
Each branch is slightly different in the training for JAG. I think the Army and Navy are pretty similar. The Marines put you through a full TBS program. I think the Air Force is somewhere in between, but I'm not sure.
No matter what, there is going to be an indoctrination course and "JAG School" somewhere in the program.