[vtkusers] moving selected actor

[Jazz Kartell]

I am new to the mailing list, so first of all, "hello" to everybody...

My goal is to visualize 3D Graph Mining algorithms.
At the moment my little program can display nodes (vtkSphereSource), 
edges (vtkLineSource) and axis.
But I want to select a node (pressing 'P' for selection works) and move 
it around to change the coordinates of a node.
Can someone give me a hint how selected actors can be moved around?
And is it possible to display some kind of labeling for actors? The only 
idea i have is to place separate 'textfields' near the actors.
Perhaps a better solution is out there?
The program is written in Java, don't know if there is a difference in 
the amount of available functionality.

Thank you very much in advance

Best Regards

Benjamin