Well that Data class, or better yet the DataAccessFacade, which has an instance of your DataAccess Interface is the Model. The controller should know about this Model, have a reference to it.
Always think of Model = data, View = GUI, and Controller is the one that handles the GUI Actions and passes it to the Model, and when the Model changes the Controller passes the changes to the View.
If you look at the JTable and understand the AbstractTableModel, and how it all works together, you will see an great example of MVC.
Here is the
JTable Tutorial at Sun.
Hope that helps. If you need more clarification we are here.
Mark