The designers and engineers were certainly ingenious in being able to turn a floatplane fighter into a land-based machine with relatively small modifications. Certainly the gear ended up being a problem, but under the wartime pressures to produce the -J it's a pretty neat solution to the design.
Here are two photos of the gear on the prototype airplane. The first shows the strut in the fully extended configuration and the second shows just how much it telescoped to shorten it for retraction. You can see in the first photo that there are two strut cylinders, one telescoping into the other and the pair then sliding up into the upper gear leg.


The production gear is a little bit less complicated looking but still has quite a lot of plumbing on it.