How works validation?

[pettersonfp]

Hello,

When you annotate a bean (i.e.: using @Range), when the validation fails, seam put a message in the proper field of the form.  How is that accomplished? 

I would like to perform validations during the execution of an action that cannot be put in a Validator, is it possible to throw some exception during the validation that will be shown at the form as a message?

Thanks in advance,

Petterson

[nickarls]

Petterson Paula wrote on Feb 20, 2008 07:25 AM:


Hello,

When you annotate a bean (i.e.: using @Range), when the validation fails, seam put a message in the proper field of the form.  How is that accomplished? 

I would like to perform validations during the execution of an action that cannot be put in a Validator, is it possible to throw some exception during the validation that will be shown at the form as a message?

Thanks in advance,

Petterson

Well, you could always write a standard JSF validator (manually or through Seam) but if you look at the Hibernate Validator docs, it is hard to find stuff that can't be done with custom validators there.

[mail.micke]

Yepp,
you can do validation in the action method and display messages.

@In
FacesMessages facesMessages;

// In your action, not important to specify correct component id
facesMessages.addToControl(
   "serverSideForm:endDate",
   new FacesMessage(FacesMessage.SEVERITY_ERROR, "message summary","message details")
   );
return null;

Can't quite remeber if the order of the message detail/summary parameters.

There is some informatin about this here (not using seam):
Tutorial

Good luck

[mail.micke]

Small type with severe consequences...

This

// In your action, not important to specify correct component id

Should be

// In your action, note important to specify correct component id

:)