DataAction prepareModel method getting called twice.

Question

I have a DataAction subclass in which I have overridden the prepareModel() method, putting a System.out.println() into. I just discovered that this method is getting called twice per time that I run the DataAction. Why is this, and how do I change it so that it is only executed once?
Brad

Answer 1

Hi:
The prepareModel method will get called each time your action is executed, ie before your page is displayed, and after a user submits a request.
If you dont want your code in the prepareModel method to be run when a user submits a request, you should check the event list. If the list is non-empty, then the user has submitted a request to your action.
The following code is taken from Steve Muench's ADFToyStore demo:
private boolean handlingEvents(DataActionContext ctx) {
    List events = ctx.getEvents();
    return (events != null) && (events.size > 0);
}in your prepareModel method, do the following:
protected void prepareModel(DataActionContext ctx) {
    if(!handlingEvents(ctx)) {
        // code for before the initial display of the page
    } else {
        // code to be executed before your event handlers get called
}HTH
Gareth