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Reply-To: struts-user@jakarta.apache.org
Subject: RE: Automatic Form Validation - A further question
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Date: Wed, 1 Aug 2001 11:51:57 +0100
Message-ID: <AD34118C0D487D478A480924DBD839F20FA3F9@moe.petrotechnics.com>
Content-Class: urn:content-classes:message
Thread-Topic: Automatic Form Validation
Thread-Index: AcEZ6RGxa7jBFMv8QE+I1L239JcwMAAjlLng
From: "Emaho, Ghoot" <Ghoot@PETROTECHNICS.co.uk>
To: <struts-user@jakarta.apache.org>

Thanks again David.

I have explored extending ActionForm to check for and ignore first time
validation. However, it seems from my debug, that the form bean is
created a new each time. Can someone else confirm this ?

My further question is this:

If I choose NOT to use automatic validation, and my request goes to the
Action first [not the JSP], then what isthe best way to determine in the
action that this is the 'first time' for this form bean i.e. it has been
created only as a result of the ActionServlet, not because it's coming
from the form on a JSP ?

I know you can check the values of the form bean, but this seems a
little messy. Any suggestions ?

Any help is appreciated, as this is an important issue for us.

Cheers

Ghoot


> -----Original Message-----
> From: David Winterfeldt [mailto:dwinterfeldt@yahoo.com]
> Sent: 31 July 2001 18:43
> To: struts-user@jakarta.apache.org
> Subject: RE: Automatic Form Validation
>=20
>=20
>=20
> --- "Emaho, Ghoot" <Ghoot@PETROTECHNICS.co.uk> wrote:
> > Thanks for the reply David.
> >=20
> > Yeah, 'action' checking is another way of
> > determining wether or not to
> > do the validation.
> >=20
> > I guess I was wondering if it was possible to
> > configure the Form to
> > prevent first time checking ? Would anyone else find
> > this useful ?
> >=20
> > Given the recent discussions about preventing direct
> > acces to JSP's, it
> > seems that the Form validation is designed [in
> > default operation] in
> > such a way as to expect that you have gone directly
> > to the JSP first.
> > This is one thing I wouldnt really ever want to do,
> > as I prefer all
> > requests to go through an action - even if it is
> > just to redirect to the
> > JSP [call me a control freak! but there area lot of
> > others that feel the
> > same :) ]
> I think it is good to go through the controller if you
> really want to keep the view separate.
>=20
> >=20
> > I wonder if the Auto Validation should accomodate
> > the more common
> > scenario [certainly in larger applications] where
> > you do want to force
> > requests thru actions and avoid direct JSP access,
> > but avoid first time
> > validation. I guess Action Form could be extended to
> > provide this, but I
> > was hoping it would already be there - as it seems
> > quite obvious and
> > important. I dont think we should be encouraging
> > people to go directly
> > to the JSP as part of the Struts framework [just my
> > 2p]
> You could always have one Action class that handles
> all things that are auto-validatded and another for
> things that shouldn't be validated.  I'm not sure how
> you could have the framework handle something that is
> specific for your application unless there was a
> parameter that could turn off the auto-validation for
> the current request
> (org.apache.struts.action.Action.VALIDATE=3Dfalse).
>=20
> >=20
> > Picking up on what you mentioned David, about
> > handling all 'actions'
> > todo with a form in the one Action class. We have
> > some sceanrios where
> > this is just not practical. What about those
> > scenarios ?!
> You can of course have as many actions to go with a
> form as you want.  I just prefer keeping it to a
> minimum.
>=20
> >=20
> > Thanks anyway David.
> >=20
> > Any other comments ?
> >=20
> > G
> >=20
> > > -----Original Message-----
> > > From: David Winterfeldt
> > [mailto:dwinterfeldt@yahoo.com]
> > > Sent: 31 July 2001 16:46
> > > To: struts-user@jakarta.apache.org
> > > Subject: RE: Automatic Form Validation
> > >=20
> > >=20
> > > If you have a variable called action that keeps
> > track
> > > of what type of action you are performing (create,
> > > update, delete), you could check for this in the
> > > validate method and only validate on create or
> > update.
> > >  The Struts example webapp has an action field to
> > keep
> > > track of this.  I wouldn't do that personally.=20
> > I've
> > > always done my validation from the Action so I
> > could
> > > use the same action for everything associated with
> > a
> > > form/table.  For example, delete doesn't need
> > > validation or sending someone through the action
> > to
> > > the view for the first time (as you mentionded).=20
> > So I
> > > don't think there is anything wrong with not using
> > the
> > > automatic validation.  I think it just depends on
> > your
> > > design preference.
> > >=20
> > > David
> > >=20
> > > --- "Emaho, Ghoot" <Ghoot@PETROTECHNICS.co.uk>
> > wrote:
> > > > Some further details on my question:
> > > >=20
> > > > I understand that you can have the request go
> > > > straight to the JSP and
> > > > avoid the first time validation.
> > > >=20
> > > > This is acceptable in some circumstance, but in
> > > > other circumstances you
> > > > may wish to have your action do some work before
> > > > presenting the page (a
> > > > common requirement in more complex
> > applications),
> > > > and you may wish to
> > > > avoid access to any JSP's directly.
> > > >=20
> > > > How then (with this extra clarification) can you
> > > > prevent the behaviour
> > > > described in the original posting ?
> > > >=20
> > > > Many thanks for any help
> > > >=20
> > > > Ghoot
> > > >=20
> > > > PS Please someone respond ! So i dont get too
> > > > disillusioned :)
> > > >=20
> > > > > -----Original Message-----
> > > > > From: Emaho, Ghoot=20
> > > > > Sent: 31 July 2001 15:49
> > > > > To: struts-user@jakarta.apache.org
> > > > > Subject: Automatic Form Validation
> > > > >=20
> > > > >=20
> > > > > Quick question on Form validation, using the
> > > > Automatic Validation
> > > > > offerred by Struts.
> > > > >=20
> > > > > If i have a form bean which performs some
> > > > validation on the validate
> > > > > method, and an action has it's definition of
> > > > validate set to=20
> > > > > true, then
> > > > > the Form Bean's validate method gets called
> > before
> > > > the=20
> > > > > action's perform
> > > > > method. However, this then displays my error
> > > > messages on the form page
> > > > > the first time i go to the page !  Am I
> > missing
> > > > something ?
> > > > >=20
> > > > > Now i can get round this with some checking in
> > the
> > > > validate method to
> > > > > ignore it the first time round - as there will
> > be
> > > > no data yet. As i
> > > > > understand, the bean is created if it isnt
> > found.
> > > > So if it's just been
> > > > > created, and then the validate method is
> > called of
> > > > course=20
> > > > > there will be
> > > > > nothing there ?
> > > > >=20
> > > > > Any suggestions ? Or does someone want to
> > point
> > > > out the obvious ?!
> > > > >=20
> > > > > In our Struts implementations to date, we have
> > > > avoided using this
> > > > > feature and done our validation from within
> > the
> > > > Action. But I am
> > > > > investigating this feature and would like to
> > know
> > > > why this is=20
> > > > > so / what
> > > > > i am doing wrong !
> > > > >=20
> > > > > Many thanks
> > > > >=20
> > > > > G
> > > > >=20
> > >=20
> > >=20
> > > __________________________________________________
> > > Do You Yahoo!?
> > > Make international calls for as low as $.04/minute
> > with=20
> > > Yahoo! Messenger
> > > http://phonecard.yahoo.com/
> > >=20
>=20
>=20
> __________________________________________________
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>=20