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Using an inner class actionListener in another class


You declared:

PrintQueue s = new PrintQueue();

inside the main() method - which means that it's available only from inside main() (method scope). If you want to use it outside the method, you'll have to declare it as a class member and expose it via a "get()" method.

For example:

public class GUI { 

  static PrintQueue s = null;  

  public static void main(String[] args) {        
    s = new PrintQueue();
    ...
  }

  public PrintQueue getS() {return s;}

Then you'll be able to use it:

public void actionPerformed
(ActionEvent e) { 
     System.out.println("The length of the queue
is: " + s.length() +"
"); //from the same class
}

or from outside the class using:

GUI gui = new Gui();
PrintQueue s = gui.getS();

Comment:
I'm not sure if main() is the right place to instantiate PrintQueue - it might be so, but it might also be that a constructor would be a better idea.


Categories : Java

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