/**
 *  This class is driver (or test harness) for an abstract factory.
 *  The concrete factory used in the program is selected by an
 *  argument of the command line.
 */
class Main {
    /**
     *  Execution entry point.
     *  @param arg Command line arguments.
     *             A string to select a concrete factory is acceptable.
     *  @exception Exception Can throw a variety of more specific exceptions.
     */
    
    public static void main (String [] arg) throws Exception {
        if (arg.length != 1) {
	    System.err.println ("A pizza style is required. E.g. \"Light\"");
	    System.exit (1);
	}
	AbstractPizzaFactory apf
	    = AbstractPizzaFactory.getFactory (arg [0]);
	AbstractCrust crust = apf.createCrust ();
	AbstractCheese cheese = apf.createCheese ();
	// sauce, toppings, etc.
	Pizza pizza = new Pizza (crust, cheese /*, sause, toppings, etc. */);
	System.out.println ("Calories: " + pizza.calories ());
    }
}