Question

I’m a struts newbie. I have a Form, an Action and a jsp view.

<form-beans>
    <form-bean name="bookEventForm" type="com.example.BookEventForm" />
</form-beans>

<action path="/bookEvent"
        type="com.example.BookEventAction"
        name="bookEventForm"
        input="/WEB-INF/jsp/bookEvent.jsp"
        scope="request">
    <forward name="success" path="/WEB-INF/jsp/bookEvent.jsp" />
</action>

One of the properties of the event form is Country so the first thing I do in Action is:

request.setAttribute("countries", countriesDao.getAll());

in the view I render the select element using:

<html:select property="..." >
    <html:optionsCollection name="countries" ... />
</html:select>

This works fine until I add ActionForm#validate to do some validation checks (unrelated to countries, e.g surname != null).

By struts spec as soon as there is an error the Action#execute never executes. Thus the countries collection is no longer in the request and the view renders with an empty select element.

I know that I’m most probably missing some core concept of struts. A friend suggested to make the dao available on the view so I can fetch the countries any time but I generaly prefer to prepare the view (prefetch db data) before any JSP “code” is executed.

Any ideas?

Answer 1

What I did to overcome the struts validate issue was to bypass struts and add my own validate method on the Form:

public ActionErrors validate() {
    ActionErrors errors = new ActionErrors();
    if (...) errors.add("name", new ActionError("error.field.mandatory"));
    if (...) errors.add("surname", new ActionError("error.field.mandatory"));
    return errors;
}

And call it from the Action:

saveErrors(request, ((BookEventForm)form).validate());

Works great and fulfills my requirements. The action is now always executed before presenting the view, the error or the success page and has code which prepares the view.