JBox2D is a close Java port of Erin Catto's excellent C++ Box2D physics engine and Google's LiquidFun physics Engine. Check out the demos below to see some examples of what it can do. (It's technically more accurate to say it's just a port of LiquidFun now, and LiquidFun is fork of Box2D, but the library started as a Box2D port.) The project has recently been moved to Github. Downloads and issue t