Please... if they were that technologically advanced to be able to build a ginormous Death Star with all the amenities AND fly around in space craft that can go hyper speeds I think they would have figured out the gravity problem....
They (both SW and ST) have artificial gravity generators. In fact, in the SW galaxy some capital ships can project a "gravity well" from their vessel which impedes other ships w/in X amount of distance from going to hyperspace.