Jayce jungle works, but he's a snowball jungle that requires a decent amount of gold to transition into the mid to late game. So you have to build him as tanky initiator/peeler if you don't get some good ganks in.
That being said, I believe his jungle clear is pretty fast last I checked, and his ganks are pretty good because of q e hammer gank, with e q cannon as follow up for the lane to counter a flash. His only problem is no real sustain, and he has some mana issues.