I have to disagree with you on this point. Consider for example a Customer Bean with two addresses: mailingAddress and deliveryAddress. The deliveryAddress is optional, so can be null. Next, I try to display (read only) the Customer properties in a JSP Page. In the current situation, before displaying the JSP page, the deliveryAddress object must exist. That is, I have to create a deliveryAddress with empty fields if a deliveryAddress is null, only for letting the Struts tag (property or write) do it's work. Why not display all requested properties of the deliveryAddress as a zero lenght string if the deliveryAddress is null. I do not like to change a model bean (model as Model in the MVC pattern) only for getting it displayed correctly on a JSP page. I agree that when trying to update or create Customer properties, an initialized deliveryAddress should be there, but then in the Form Bean. Arjan Kok > -----Original Message----- > From: Craig R. McClanahan [mailto:[EMAIL PROTECTED]] > Sent: Thursday, January 11, 2001 6:49 PM > To: [EMAIL PROTECTED] > Subject: Re: cvs commit: jakarta-struts/web/test html-multibox.jsp > html-setters.jsp > > > "Kok, Arjan" wrote: > > > Hello Craig, > > > > What happens if in the code snippet <html:text > > property="mailingAddress.street"/> mailingAddress is null? > I would expect > > Struts not to raise an exception for initial display when > mailingAddress is > > null, because Struts will also not raise an exception when > street is null. > > If Struts raises an exception in the former, I would like > an opportunity in > > Struts to check if there is a nested bean (e.g. by extending the > > logic:present tag). > > > > Right now, Struts would throw an IllegalArgumentException > ("Null property value > for 'mailingAddress'") if the mailingAddress property is null. > > If mailingAddress is not null, but mailingAddress.street is > null, a null will be > returned from PropertyUtils.getProperty(), which will > ultimately display as a > zero length string in an <html:text> tag. > > IMHO this is appropriate behavior. It is up to the > application designer to > ensure that all of the property values before the last one in a nested > expression are valid and non-null. In Java terms, that means > the tags expect > you to have initialized an Address with empty fields, and called > setMailingAddress() on your underlying bean, as part of the > initial setup of the > "outer" bean. > > > > > > Arjan Kok. > > Craig > >
