Apple WebObjects 3.5 - Manual (Page 50)

Chapter 2 Enhancing Your Application
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3. At the top of the Application class definition, enter this declaration:
protected MutableVector allGuests;
This declares allGuests to be of type MutableVector. Declaring it
protected means that it is accessible only from this class or one of its
subclasses. It is standard object-oriented practice for a class to prevent
other classes from directly manipulating its instance variables. Instead,
you provide accessor methods that other objects use to read or modify the
instance variables.
4. Add the accessor methods addGuest and clearGuests , as shown in the figure.
The addGuest method adds an object of class Guest to the end of the allGuests
array, using the MutableVector method addElement (its Objective-C
equivalent is addObject ).
The clearGuests method removes all the objects from the array using the
MutableVector method removeAllElements (its Objective-C equivalent is
removeAllObjects ).
5. Save Application.java .
Adding Guests to the Guest List
Now, when the user submits the form, you’ll add the information to the allGuests
array rather than displaying it directly.
1. Switch to the code for Main.java .
2. In the submit method, add the following code before the return statement:
((Application)application()).addGuest(currentGuest);
currentGuest = new Guest();
This code calls the application’s addGuest method, which adds an object (in
this case, currentGuest ) to the end of the array. Then it creates a new Guest
object to hold the next guest’s data.
Note: The addGuest method is defined in the class Application, which is a
subclass of WebApplication. The component’s application method (called in
the above statement) returns an object of type WebApplication, so you
must cast it to Application in order to access its
addGuest method.
Your next step is to create a new component to display the list of guests that
allGuests stores.