design pattern

[Hugo Batista]

Hi everybody,

I would like to have your opinion...


Imagine i have a pattern that defines:

- abstract factory : my consumer always handle with a interface and not with
direct implementation, and calls a factory to get an object instance;
- the kind of object returned in that instance varies according to some
settings and, in runtime, the factory reads settings and return the
configured object type that implements interface;
-Singleton/singlecall: the returned object can be singleton or singlecall
and that can be changed in settings at any time. The consumer should not
care about this and the factory handles this to know if he should mantain a
singleton instance or not;
- inproc/outproc : the object can be a remote one or a local one. the
consumer does not know this and the factory handles it all. that is also
defined in settings;


a settings example:

<PatternProviderSettings xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ObjectMode>SingleCall</ObjectMode>
<AllowWeakReferenceOnSingleton>false</AllowWeakReferenceOnSingleton>
<ProcessModel>InProc</ProcessModel>
<RemotingUrl>tcp://localhost:9999/LocalPatternsProvider</RemotingUrl>
<Provider>DotNetX.CodeGeneration.Patterns.LocalPatternsProvider,
DotNetX.CodeGeneration</Provider>
</PatternProviderSettings>



- Objectmode allows singleton or singlecall
- AllowWeakReferenceOnSingleton indicates to the factory if he should keep a
weakreference or a reference, so the GC can handle it if needed
- ProcessModel indicates inproc or outproc
- RemotingUrl indicates the object remote url if outproc
- Provider indicates the final implementation (the type of object to be
created)


my question is:
between existing enterprise patterns, which do you think that apply to this
? i already know that abstract factory applys, but i wonder if other also
apply ... what about strategy design pattern ? do you think it applies ?


regards!
and thanks for your contribution..
HB

www.dotnetx.org

 

[Nick Malik [Microsoft]]

The pattern is called Inversion of Control. It is heavily described in
various literature and forms the basis of a branch of computing called
Aspect Oriented Programming.

There is a port of the AOP framework "Spring" in the .Net spaces available
here:
http://www.springframework.net/

This is an exciting area, and I encourage you to dig in.

--
--- Nick Malik [Microsoft]
MCSD, CFPS, Certified Scrummaster
http://blogs.msdn.com/nickmalik

Disclaimer: Opinions expressed in this forum are my own, and not
representative of my employer.
I do not answer questions on behalf of my employer. I'm just a
programmer helping programmers.

 

[Hugo Batista]

Hi Nick

thanks for your answer.

don't you think it's something more closer from Strategy Pattern ?
I would also like to mention that this is not done without any kind of
injection or interception. the factory only reads settings and determines
what kind of object and how to create it...

regards

 

[Hugo Batista]

Nick

just forget it. you're perfectly right! after reading the quick tutorial to
Spring i've just concluded that this is exactly what i was looking for...

for curiosity.. i'm using this since 2 years ago in an opensource object
relational persistence framework i'm having called DotNetX.. and i was
calling it Remotable Plugin Pattern... glup... reinventing the wheel!



regards!