----- Original Message -----
From: Stefano Mazzocchi <stefano@apache.org>
To: <cocoon-dev@xml.apache.org>
Sent: Wednesday, May 31, 2000 10:01 PM
Subject: Re: Cocoon2 Design
>
> Concerns should _not_ forced to be separated, but only when they belong
> to different to different concern groups.
>
> For example, suppose you have a URI of the form
>
> /sql/employees/add
>
> (I know it's ugly, just an example) which indicates what technology you
> are using. Then if you change the technology, you have to change your
> URI. This is not different from having an extention on the URI itself.
>
> /employees/add.sql
>
> But if you do
>
> /employees/add
>
> alone, you are both indicating you want the "resource that allows me to
> add an employee". No matter what technology you use, you are still in
> shape and you URI doesn't require to change.
>
> So, to summarize: contracts should not change and all development and
> design must be done to enforce this.
>
Agree - This is a classic example of the dependency inversion principle
[R.Martin] which states;
Implementation details should depend on abstractions, not abstractions
depend on implementation details.
regards
Rob
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