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Re: MVC Partner

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Em quarta-feira, 26 de novembro de 2014 18h40min36s UTC-2, lipska the kat  escreveu:
> On 26/11/14 19:16, Leonan Luppi wrote:
> > Hello Guys,
> >
> > I have some doubt about MVC. Someone could solve please?
> >
> > So for my "M" it's need to be my mirror of DB (Entity mapped my JPA for example)?
> >
> > For my "V" it's need to be interfaces which only show and send to my controller?
> >
> > For my "C" it's need to be all business rules, calling my DAO to result from DB ?
> >
> > Someone can give an example please?
> >
> 
> I really think that there is an awful lot of mis-information out there 
> about MVC. For example the wikipedia article mentioned by another 
> responder talks about MVC being a 'design pattern' when effect it is a 
> combination of several design patterns. I think 'paradigm' might be a 
> better word.
> 
> The *original* idea behind MVC was that you had a Model, this could be 
> any persistent store, often but not exclusively a database. The 
> Controller was responsible for updating the Model in response to 
> interactions with the View. There could be many Views on the Model each 
> of which registered themselves with the Controller and each of which 
> were updated in response to an interaction with any one of them. so for 
> example you could have 3 Views, possibly on 3 different devices and if 
> any View was modified by a 'user' the state of the Model was first 
> updated by the Controller which then updated *all* the views that were 
> registered with it at the time. The finer details escape me, it was some 
> years ago when I studied this.
> 
> With the advent of Java, Sun came up with something called Model2 IIRC.
> In this case you still had your persistent store but the Controller was 
> a Servlet (or rather the interface to the Controller was a Servlet) and 
> the view was (classically) implemented as a JSP.
> 
> The fundamental difference is that because http is a request/response 
> protocol and there is no way to 'push' changes initiated by one view to 
> other views.
> 
> Things may be slightly different now with the advent of asynchronous 
> technologies such as Web Sockets.
> 
> So, in the classic 3 tier Model 2 web application you have an SQL 
> database which would be your Model, a Servlet engine such as Tomcat 
> which would host your Servlets (your Controllers) and a (arbitrary) 
> client, let's say in this case a web browser, to which you would deliver 
> your View implemented as a JSP
> 
> Your business logic is typically accessed through a facade accessed by a 
> Servlet, your business logic would communicate with a facade onto your 
> database, this would initially be an Interface.
> 
> The single most important thing to remember is that your business logic 
> should be completely decoupled from the View *and* from the Model. In 
> this way you can deliver your content to any interface, not just a web 
> interface and persist you data to any type of persistence mechanism.
> 
> 
> -- 
> lipska the kat - treacherous feline.
> Proudly nominated for IPOTY 2014 - LIGAF
> ==================================================
> Any GNU/Linux distribution that does not come with
> the set of tools required to build its open source
> kernel is incomplete. This is an opinion.
> ==================================================
> GNU/Linux user #560883 - linuxcounter.net

Thanks lipska. So if I understand, for you the controller must contain the business logic?

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MVC Partner Leonan Luppi <leonan.luppi@gmail.com> - 2014-11-26 11:16 -0800
  Re: MVC Partner Arne Vajhøj <arne@vajhoej.dk> - 2014-11-26 14:56 -0500
    Re: MVC Partner Leonan Luppi <leonan.luppi@gmail.com> - 2014-11-26 14:54 -0800
      Re: MVC Partner Arne Vajhøj <arne@vajhoej.dk> - 2014-11-26 18:07 -0500
      Re: MVC Partner Martin Gregorie <martin@address-in-sig.invalid> - 2014-11-26 23:22 +0000
  Re: MVC Partner lipska the kat <lipskathekat@example.com> - 2014-11-26 20:40 +0000
    Re: MVC Partner Leonan Luppi <leonan.luppi@gmail.com> - 2014-11-26 15:01 -0800
      Re: MVC Partner lipska the kat <lipskathekat@example.com> - 2014-11-27 08:56 +0000

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