Behavior initiation - getTransform form ref node

Question

I have a behavior that runs every frame updating the position of a few objects. Right now the initial transform for those objects is set at the behavior initiation.
I would like to set the transform for the object when I build the scenegraph and then use the behavior to update the initial values.
I have tried getting the original values both in the constructor and the initialize() and the procesStimulus() methods of the behavior. I get a **java.lang.NullPointerException** every time.
It's as if the behavior can't read the value of the TransformGroup that
its supposed to change. Here is part of the code:
public gUserBehavior(TransformGroup tg_usership,TransformGroup tg_view){
tg_userTrans = tg_usership;
viewGroup = tg_view;
public void initialize() {
this.wakeupOn(kEvent);
tg_userTrans.getTransform(tr_userT); //this generates the error

Answer 1

Are the following set ?
For the TransformGroup :
setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
For the branchGroup :
setCapability( BranchGroup.ALLOW_CHILDREN_READ );
setCapability( BranchGroup.ALLOW_CHILDREN_WRITE );
Also,
The variable should be declared like the following :
// e.g. not TransformGroup abc = new TransformGroup()
// for this case.
TransformGroup tg_userTrans = null;
TransformGroup viewGroup = null;
public gUserBehavior(TransformGroup tg_usership,TransformGroup tg_view
tg_userTrans = tg_usership;
viewGroup = tg_view;