JavaFX 2.0 :: Variables With Multiple FXML Files

I have a multi scene JavaFX FXML application [URL] ....
 
I have added a TextField to Scene2.fxml and Scene3.fxml files each scene has its own Controller Class with a ScreensController class that loads a HashMap with Id name, Node screen that is defined in the ScreensFramework

class (Main class)
public void addScreen(String name, Node screen) {screens.put(name, screen);}

So each time you click a Button on a screen (scene) you fire an ActionEvent and move to another screen

myController.setScreen(ScreensFramework.screen2ID); 

What I would like to do if it is possible is use the value in the TextField on Sceen2 and transfer it to the TextField on Scene3. I have discovered that unless both FXML files are loaded this is so far not possible. This is a desktop application. So how do you create a variable that is GLOBAL and has a life after one class is unloaded or one FXML file is unloaded?

At this point I do not want a database to accomplish this task.I have developed in Visual Basic 6 where I would just declare a global variable that could be used through out the application.