Filtering an array of EO objects (next hurdle)
Filtering an array of EO objects (next hurdle)
- Subject: Filtering an array of EO objects (next hurdle)
- From: Ray Ackland <email@hidden>
- Date: Mon, 10 Nov 2003 09:37:26 +1300
JP,
Well, I've been playing around with giving these things a go, and have
started discovering what some of the side effects can be. Unfortunately
it looks like all the options I listed are subject to something.
I have realised that if you replace the standard cover method for
returning the related records, everything goes great - until you want
to insert another record. This seems to call the replaced method (not
sure why it calls a get method first) and in my tests used the
incomplete and adjusted fetch - resulting in bad mojo. And yes, I had
been warned about travelling in dangerous territory, but I need to
explore these things for myself.
Why I tried replacing the cover method is because doing an additional
method didn't produce the results I wanted either. Remembering that
this is D2J, it appears that the rule system looks in the EOModel to
see what kind of object is going to be returned by the accessor
methods, as it can't tell from the code (just specifies NSArray).
When I create a secondary method to return the filtered array, the rule
system doesn't know what kind of objects the array contains and so
doesn't format it in a table or form as it would the normal method.
Does anyone know how to tell the rule system to treat a custom method's
return values (in an array) as EOObjects?
Ray.
On Thursday, Nov 6, 2003, at 02:03 Pacific/Auckland, Jean Pierre
Malrieu wrote:
Le 5 nov. 03, ` 09:10, Ray Ackland a icrit :
Jean Pierre,
I am aware of the use of display groups in nib files with standard
Java client apps, but does it apply to Direct to Java as well?
Sure. Controllers in D2JC use display groups too.
D2JC will not allow you to make as much performance tuning as JC.
What I would do if I were you, is to (custom) fetch on the server side
(throuh remote method invocation), getting only the EOs you want. Then
you can pass an array to the client containing just the info you need
(maybe just an array of strings!). Then on the client side, you can
use swing components, or reconstruct lightweights EOs from the array
and put then in your display groups. But that's not a D2JC approach.
Assuming you don't need such an extreme optimization, I don't
understand why you don't want to fetch on the server side, using
custom fetch spec that return just the EOs you need (solution b/)
If you want to (custom) fetch on the client-side, WO will synchronize
your EOs with the server side each time you save your data, so I don't
understand what problems you are afraid of running into (solution c/).
Good luck.
PS: I know a JC expert who does JC optimization for a living here in
France, but as she is expecting to welcome two adopted kids this week,
I don't think we should bother her with our questions right now!
Goog luck.
JP.
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