Collision Help

Hi,  I'm currently using jME Physics and I'm not sure how to check for collisions.  To clarify, I'm not sure how to get a boolean value of one of my dynamic nodes(sphere) collides with one of my static nodes(tube).



And also, how would I eliminate any direction that will cause this dynamic node to collide with my staticnode.  For example, if I had a ball colliding in a tube, how would make sure that a new random direction will not cause an immediate collision?



Thanks a bunch

Anyone?