24.12. Pet Store Example: The Do Checkout Rule

  1. The Do Checkout rule is part of the default (MAIN) agenda group. It always calls the doCheckout() functionwhich displays a 'Would you like to Checkout?' dialog box.
  2. The doCheckout() function sets the focus to the checkout agenda-group, giving the rules in that group the option to fire.
  3. The rules in the checkout agenda-group display the contents of the cart and apply the appropriate discount.
  4. Swing then waits for user input to either checkout more products (and to cause the rules to fire again), or to close the GUI.