public static void checkCollision(Collidable a, Collidable b, int expected) {
        checkCollisionBase(a, b, expected);
        checkCollisionBase(b, a, expected);
    }
Tests various collisions between the two collidables and 
the transitive property.

@param a First collidable
@param b Second collidable
@param expected the expected number of results
jme3-core/src/test/java/com/jme3/collision/CollisionUtil.java