Re: [Hibernate] type safe criteria queries

[Max R. A. <max...@jb...>]

> Hi I am sending this again could anyone tell me if this might be usefu=
l
> to the communitY? I would like to help if it would be.

 From the look of it looks like something that is "evil" since that code=

will not do what it actually states.

Why not simply generate a MyClassProperties class that list the property=
  =

names
and use that to refer to some compiletime safe name ?

Sounds much simpler and portable imo.

/max

>
> Thanks,
>
>
>
>
> Dhanji,
>
>
>
>
> ________________________________
>
> From: hib...@li...
> [mailto:hib...@li...] On Behalf Of
> Dhananjay Prasanna
> Sent: Wednesday, 28 June 2006 11:31 AM
> To: hib...@li...
> Subject: [Hibernate] (semi) Entity-type safe criteria queries
>
>
>
>
> Hi All
>
>
>
>
> I am writing to ask about type-safety (in a very rudimentary way) in
> Criteria queries. I know there has been some discussion around this
> topic with the SODA group and others, but I am curious if this has bee=
n
> considered for Hibernate.
>
> Basically, instead of using the system:
>
>
>
>
> Criteria q =3D session.createCriteriaQuery(MyClass.class);
>
> q.add ( Restriction.eq( "propName", value) );
>
>
>
>
> which is unsafe to the entity-type under query, would it be possible t=
o
> do something like:
>
>
>
>
> Criteria q =3D session.createSafeCriteriaQuery(MyClass.class);
>
> MyClass my =3D q.obtainQueryable(MyClass.class);
>
> q.add( Restriction.eq( my.getPropName(), value ));
>
>
>
>
> The special instance "my" would contain proxies or bytecode-instrument=
ed
> properties that would return the appropriate mapped property name to t=
he
> Criterion. Apart from being safe to the Entity type under consideratio=
n
> (statically) and its properties, this approach has the added advantage=

> of bringing criteria queries into an IDE's refactoring scope.
>
>
>
>
> The cons are the added performance hit of proxies or bytecode
> manipulation, and the extra step in obtaining a reference to a queryab=
le
> entity. However I believe the pros far outweigh this, as my own projec=
t
> occasionally undergoes property-refactoring and has a LOT of
> similarly-named properties across classes (too many for a sane person =
to
> discriminate on sight!).
>
> Anyway, I thought I would bring it up-Im sure typesafety has been
> discussed before so please forgive me if this is a rehash. I'm also
> happy to contribute an implementation of this if you guys find it wort=
h
> adding.
>
>
>
>
> Thanks!!
>
>
>
>
> Dhanji.
>
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> If you receive this correspondence in error please delete it from your=
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> Any opinions expressed in this message are those of the individual  =

> sender except where the sender expressly,
>
> and with the authority, states them to be the opinions of the Departme=
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-- =

--
Max Rydahl Andersen
callto://max.rydahl.andersen

Hibernate
ma...@hi...
http://hibernate.org

JBoss Inc
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