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Re: What is the benefit of OPF?


2006-05-28 11:28:34 PM
delphi187
"Bob Dawson" <XXXX@XXXXX.COM>wrote
Quote
Even for small individual projects--especially
greenfield work--packaged frameworks like Bold/ECO are becoming really
attactive.
Actually, I'd advise using Bold/ECO for a while rather than attempting
to write your own OPF. If you eventually do decide to write your own you'll
have more experience and a better idea of how to do it.
Regards,
Danny
 
 

Re: What is the benefit of OPF?

"Bear" wrote
Quote
It seems that:
1. The OPF is not suitable for small project (1-3 man/month).
2. The OPF is suitable for large and complex project or long time product
of
a company.
1. I don't think that a single, short-term project can justify writing an
OPF, no. However, if as a consultant/contracter you realize that you're
going to be meeting the same general needs for client after client, then
having an OPF on your shelf might be a distinct advantage. Generic code pays
for itself with reuse and improved maintenance/expansion possibilities.
Ought to note, however, that using an OPF and writing one are two
different issues nowadays. Even for small individual projects--especially
greenfield work--packaged frameworks like Bold/ECO are becoming really
attactive.
2. Definitely.
bobD
 

Re: What is the benefit of OPF?

Quote
But the goal of a project does not care about that.(the developers care
about that)
Well, yes and no. It depends how you define the goal of the project. Some
strategies work better for the long-term life of the project than others. But if
your project goals are very simplistic, then perhaps.
Quote
Sometimes the stored procedures or constrains can do things faster and
easier.
Occasionally. Most of the time it is not true, though. It is definitely less
maintainable to have code there, IME, so as in all things, there is a trade-off.
In any case, an OPF does not necessarily preclude the use of stored procs.
Quote
It depends on what the problem is and how we think about the problem.
I don't believe the first part of that to be true. If you only think in terms of
RDBMSs then you will only ever see them as solutions, of course.
Quote
For example, a Book Rent system, the client will pay it for 2000 USD ,
and want to get the software in 2 month. (small project)
And if you have an OPF already, it is almost certainly the quickest way to
produce that. If you have to write one, then maybe not, although simple OPFs are
quick to write.
And I think you might be undercharging, BTW :-)
Quote
So we can't earn money :( .
Only because you are not familiar with that way of working and do not have the
tools. If you had to learn how databases worked it would take you longer too.
Quote
Agree. It 's layered design.
And that is very difficult to do with DA controls and dataset components (I
would say impossible to do well)
Cheers,
Jim Cooper
_____________________________________________
Jim Cooper XXXX@XXXXX.COM
Skype : jim.cooper
Tabdee Ltd www.tabdee.ltd.uk
TurboSync - Connecting Delphi to your Palm
_____________________________________________
 

Re: What is the benefit of OPF?

Quote
You seem to think an OPF has to be coded specifically for every project, but
that is exactly what a good OPF *avoids*.
With the caveat that changing platforms might be a problem, eg I had to write a
simpler one for a PocketPC app
Cheers,
Jim Cooper
_____________________________________________
Jim Cooper XXXX@XXXXX.COM
Skype : jim.cooper
Tabdee Ltd www.tabdee.ltd.uk
TurboSync - Connecting Delphi to your Palm
_____________________________________________
 

Re: What is the benefit of OPF?

Quote
I found an OPF Example:
There are loads of OPFs in the .NET space (reflection makes writing them so much
easier, and you can hook objects up to controls which makes GUIs easier). Many
of them are freeware (NHibernate is a version of the popular Java OPF, for example)
Cheers,
Jim Cooper
_____________________________________________
Jim Cooper XXXX@XXXXX.COM
Skype : jim.cooper
Tabdee Ltd www.tabdee.ltd.uk
TurboSync - Connecting Delphi to your Palm
_____________________________________________
 

Re: What is the benefit of OPF?

"Daniel Mauric" wrote
Quote

Actually, I'd advise using Bold/ECO for a while rather than attempting
to write your own OPF. If you eventually do decide to write your own
you'll
have more experience and a better idea of how to do it.
In general, it is always better to buy than build if a suitable product
exists.
Only two cautions:
1. Bold/ECO is much more than an OPF--I'd call it an application
framework
2. There's always a considerable difference between any specific
product and the product type in general. Roses have scent and thorns--but
that's not true of all flowers, and not even equally true of all roses.
Picking any single product as a test of a concept is apt to be misleading.
bobD
 

Re: What is the benefit of OPF?

"Bear" wrote
Quote
I found an OPF Example:
www.codeproject.com/csharp/opfnet.asp
I will study it.
See my response to Daniel Mauric, which applies here as well. Try to
distinguish as best you can between the strengths and weaknesses of OPF.NET
in particular, and the OO, layered-design, OPF approach in general.
Here are some other sites to browse
spaces.msn.com/johnysmith/Blog/cns!383F83B16A61FB36!374.entry
www.mygenerationsoftware.com/portal/default.aspx
www.15seconds.com/issue/040112.htm
csharp-source.net/open-source/persistence
bobD
 

Re: What is the benefit of OPF?

Thanks much for the links.
Bear
"Bob Dawson" <XXXX@XXXXX.COM>写入消息新闻:4479ea25$XXXX@XXXXX.COM...
Quote
"Bear" wrote
>I found an OPF Example:
>www.codeproject.com/csharp/opfnet.asp
>I will study it.

See my response to Daniel Mauric, which applies here as well. Try to
distinguish as best you can between the strengths and weaknesses of
OPF.NET
in particular, and the OO, layered-design, OPF approach in general.

Here are some other sites to browse
spaces.msn.com/johnysmith/Blog/cns!383F83B16A61FB36!374.entry
www.mygenerationsoftware.com/portal/default.aspx
www.15seconds.com/issue/040112.htm
csharp-source.net/open-source/persistence

bobD


 

Re: What is the benefit of OPF?

Quote
I'm currently working on a project to provide downloadable television and
radio content for the BBC, and our part of the project will only use OPFs
for talking to databases.
Red Bee by any chance? Put in a good word for me while you're there?
;-)
Quote
Could you please provide some real projects that use OPF and the project
background?
I'm discussing a project to run graphics live to air which would be driven
entirely by an OPF (ECO and Bold). We also use an OPF (Bold) to run TV
channels for around 200 shops and offices in the UK.
Bryan
 

Re: What is the benefit of OPF?

Quote
For example, a Book Rent system, the client will pay it for 2000 USD ,
and want to get the software in 2 month. (small project)

If we look it as a database and data processing application,
we can design E-R diagram first,
then use Delphi develop it with DataModule/ClientDataSet/DAControls etc.
We can do it with 1 developer in 1 month.
We can earn some money :). (and we use many dataset objects too)
When using Bold or ECO you start by modelling in UML - very similar to
modelling in E-R. Possibly add 20% to the modelling time to model behaivour
as well as data. You'd be looking at a few days of modelling. Then you hit
a button and generate your schema, your app framework, all your classes,
then just fill in the process code. GUI building takes the same time for DB
or for OO thanks to Bold and ECO's databinding.
So you will find that you can actually work faster with a good OPF than with
traditional DB style apps.
I found that when I moved to Bold for the first time, within a few months I
was working just less than 5 times as fast for a project from end to end.
Now I have been using it for 5 years I work even faster in it.
Bryan
 

Re: What is the benefit of OPF?

Quote
Red Bee by any chance? Put in a good word for me while you're there?
;-)
I already have :-)
Cheers,
Jim Cooper
_____________________________________________
Jim Cooper XXXX@XXXXX.COM
Skype : jim.cooper
Tabdee Ltd www.tabdee.ltd.uk
TurboSync - Connecting Delphi to your Palm
_____________________________________________
 

Re: What is the benefit of OPF?

"Jim Cooper" <XXXX@XXXXX.COM>writes
Quote

>Red Bee by any chance? Put in a good word for me while you're there?
>;-)

I already have :-)
Ta muchly!
B