@Override
    public void write(JmeExporter ex) throws IOException {
        OutputCapsule capsule = ex.getCapsule(this);
        capsule.write(nodeA, "nodeA", null);
        capsule.write(nodeB, "nodeB", null);
        capsule.write(pivotA, "pivotA", null);
        capsule.write(pivotB, "pivotB", null);
    }
destroys this joint and removes it from its connected PhysicsRigidBody's joint lists
jme3-jbullet/src/main/java/com/jme3/bullet/joints/PhysicsJoint.java