protected void setRigidBody(PhysicsRigidBody body) {
        assert body != null;
        assert rigidBody != null;
        rigidBody = body;
    }
Alter the rigid body for this link.

@param body the desired rigid body (not null, alias created)
jme3-jbullet/src/main/java/com/jme3/bullet/animation/PhysicsLink.java