Re: Binding problem in .jsp page

From:

Lew <lew@lewscanon.com>

Newsgroups:

comp.lang.java.programmer

Date:

Thu, 30 Jul 2009 11:00:26 -0700 (PDT)

Message-ID:

<2527f72a-e66b-41f9-a2d0-7d03cc4af279@q14g2000vbi.googlegroups.com>

Mongoose wrote:

<h:graphicImage binding="#
{carstore.models.Jalopy.components.imageSmall}" />

and I'm getting this error:

"Cannot coerce type java.lang.Object to
javax.faces.component.UIComponent"

How do I best deal with the type mismatch??

Lew wrote:

What is the backing bean code? The contents of the application
configuration resource file?

The message is telling you that the 'imageSmall' property is not a
pointer to a UIComponent.

I am not certain why you get the error, but I observe some potentially
relevant facts.

- 'carstore.models' is declared as a raw 'Map', which means that it
returns an element of type 'Object'. The same is true of the
'carstore.models.Jalopy.components' retrieved value. Something in the
retrieval of these values, probably the 'components' attribute, is not
keeping track of the actual run-time type. I would attempt adding
generics to the Java code, but I don't know if that will help.

- The project may include a 'CarBean' converter that would fix that,
but I didn't see it.

- The JSP code you show does not have the problem line you described:
  <h:graphicImage
    binding="#{carstore.models.Jalopy.components.imageSmall}"
    />

I don't have the answer, but perhaps these observations will help.

--
Lew