Comments on: Putting SPELs on ADF Code

By: hans

hans — Tue, 07 Dec 2004 18:22:38 +0000

Hey Leon,
you’re right, I got JSTL and EL mixed up. There’s only so much new technology I can take
Still I’m not too fond of using EL in code; and looking back, I see you’re mentioning the point yourself:
‘But be sure to SPELL your expressions right to avoid runtime errors’. Making a typo in a getter would of course
get you a compile-time error…

By: Leon van Tegelen

Leon van Tegelen — Sat, 04 Dec 2004 11:07:23 +0000

Hi Hans
I didn’t say there was a point to it . It is just an alternative way of making your way through the objects. If the performance penalty
isn’t too big I see no harm. Your other argument does not hold completely. eval.getValue(â€?${mybean.property}â€?) will actually return a null value
not an empty String. In JSTL it is true that a null value will be represented as an empty String, but that makes sense in JSP.
Also in both cases there is an equal amount of casting.
Interestingly enough, in the source JDeveloper delivers with the ADF code ( adfc directory onder JDEv home ), the evaluator is not used. That makes you
wonder why Oracle supllied it all. Maybe there is a dependency in the framework code they didn’t supply.
I’ll put a post on OTN on the topic

By: hans

hans — Fri, 03 Dec 2004 20:28:19 +0000

Hi Leon, I can’t see the point of doing so. Where’s the gain? Less typing?
In fact, wouldn’t you be hiding errors in cases where objects are null, eg
wouldn’t eval.getValue(“${mybean.property}”) evaluate to an empty string when
mybean can’t be found / is null? Doing it in code would give you a NPE telling you there’s
something wrong, while an empty String might go unnoticed…