General talk about software patterns

["Ralph Johnson" <johnson AT cs.uiuc.edu>]

On 3/22/07, Dragos Manolescu 
<dmanoles AT gmail.com>
 wrote:
> Are there any studies that focus on how do the types of patterns used in
> software systems change as these systems mature? My intuition tells me that
> in general (i.e., regrdless of problem domain and/or programming language)
> new, immature systems tend to employ more creational patterns than
> behavioral patterns. However as the abstractions crystallize the number of
> behavioral patterns should increase.

I've never seen any study of this.

It probably depends on what you mean by "mature".  If a system was
built by a few very experienced people and then maintained by a larger
group of less experienced people who do not have a deep knowledge of
the system and so try to make as few deep changes as possible, then a
system might have less design patterns as time goes by.  But if a
system is maintained by (some of) the people who built it and they are
concerned about changing the design of the system to make it easy to
maintain then it ought to have more patterns over time, and that would
hold for all of them.  I agree that creational patterns are easier to
spot and might appear earlier.

-Ralph