This class is called from frameMain which extends JFrame:

public class Print extends JPanel implements ActionListener, Printable {
....
   if (job.PrintDialog()) {
               ...
   }
....
}

It is a typicall print class which works fine:
Print print = new Print(...)

But if I wrote print = null and create it again:
print = new Print(...)

after I press the print button, I got 2 print dialog (or more if I created
it more times).

Why?
What I must to initialize again?

p.s.
I even started System.gc();