Re: Register arbitrary types Framework

On Thu, 18 Mar 2004, Markus Schaber wrote:

> > With getObject you can register the factory with a pg internal type
> > name that the driver knows, but with setObject you have nothing to
> > determine which (if any) factory to use other than the object itself.
> > You could work on some kind of reflection based scheme, but this is
> > certainly not symmetric with how getObject works.
>
> Every Object's class can be obtained with the getClass() method. So (as
> I weakly hinted in my original post) we can have a Map with the
> classes (or fully qualified class names) as keys, and the factories as
> values. Using a HashMap as Map, this allows us to find the factory in
> constant time (*).
>
> I also think that the current setObject(int, Object) using an 13-branch
> if(instanceof)-else construct could be sped up by this - of course, at
> the cost of creating the appropriate factory classes.
>

Well this cleanup is something I'm actually more interested in, my work on
adding COPY support to the driver has kind of stalled because I need the
ability to read/write internal data types and all of this knowledge is
contained in the Statement/ResultSet classes.

> (*) Of course, correct handling of subclasses is a little more tricky,
> but I already have some ideas on how to handle this problem. But
> as I don't want to overload this message, I'll outline them in another
> Followup.

Yes, this is an issue I hadn't considered and am interested to see your
reply.

Kris Jurka