Thanks for your comments Harmeet.
My main concern was that it makes these various bits of code bigger
and more complex, and to balance that I'm wondering what the need
is... ie what benefit comes from it? I know there are theoretical
benefits like "at some point someone might want to do something
different" but that is highly hypothetical, and in theory one can put
an infinite amount of effort into hypothetical needs and never
actually solve any real problems.
Anyway, your point is good Harmeet that this could actually introduce
a weak point where customizers could create more issues.
I suppose my problem is that I've just never run into a need for
something like this... so I find it pretty low on my "care about"
meter, and if Adrian wants to go for it then great! ..and hopefully it
will do more good than harm should it ever do much of either.
-David
On Nov 10, 2009, at 9:58 PM, Harmeet Bedi wrote:
I think TimeDuration is a useful base type. It is something that
exists in .NET system package (TimeSpan class) but has not been
given as much importance in java land. I personally prefer name
TimeSpan over TimeDuration.
I think very nice to replace if-then-else with OO equivalents. Ofbiz
has too much if then else.. Makes things harder to extend.
On a note of caution. Currently system has very few fundamental
types and everything has to be built from those few blocks. It keeps
the foundation very simple.
Custom data types can be powerful but it could be bad if different
apps start adding their own types and building on that. Maybe this
is something that should be reasonably easy to add at system level
but users should not be encouraged to add types.
Harmeet
----- Original Message -----
From: "Adrian Crum" <[email protected]>
To: [email protected]
Sent: Tuesday, November 10, 2009 10:40:54 PM GMT -05:00 US/Canada
Eastern
Subject: Discussion: User-Defined Java Data Types In The Framework
I first started thinking of this idea in a Jira issue:
https://issues.apache.org/jira/browse/OFBIZ-3125
I thought it would be easy to extend the framework to support a new
Java object type (or class). I wanted to be able to pass around a
TimeDuration instance in services, mini-lang, screen widgets, etc. I
thought it would be easy. It wasn't.
Those framework artifacts convert Java objects from one type to
another using the ObjectType class. I had to make changes to a huge
monolithic if-else-if block in that class. Then I had to modify some
code in the Entity Engine. I couldn't get the Entity Engine to
support the TimeDuration class because of two monolithic switch
statements where Java data types are mapped to integers, but not in
a centralized way.
I stopped trying to wedge the TimeDuration class into inflexible
code, and instead started working on making the code more flexible.
I replaced the monolithic if-else-if block in ObjectType with
polymorphism. Now components can extend the framework with their own
Java object type conversions.
I still need to work on the Entity Engine. I would like to replace
its monolithic conditionals with the new conversion code. Before I
get started, I wanted to present the idea to the community to see if
there were any objections.
The goal is to make it easier for developers to add new Java data
types to the framework. I see this as a big benefit to writing OFBiz
add-ons or customizations.
What do you think?
-Adrian
