Re: UMLish modellers?
Re: UMLish modellers?
- Subject: Re: UMLish modellers?
- From: Drew McCormack <email@hidden>
- Date: Sun, 9 Sep 2001 11:21:14 -0700
If there is no rational specification for a piece of software, there is
no
way to verify that the software meets the specification at the end of
the
project. What is the point of designing something that is not
specified ?
How is a design evaluated without a specification to compare?
Specifying
non-trivial software a-priori is very hard!
Yes, I think you are right, but I don't think anyone that uses UML would
say you don't need a software requirements or specification document.
UML helps with the design phase, but doesn't mean you avoid the other
parts of the process.
I think the following is a typical software process:
User Requirements
Software Requirements
Software Specification
Software Design
Unit Testing
System testing
Acceptance testing
Something like that. I think UML is only really useful for Software
Design. That doesn't mean it is entirely useless. My experience is that
it is quite an expressive graphical language to document a complex
design. If you work alone, it may be less useful, but if you have many
people writing the software, it is a good means for communicating design
aspects, and make sure everyone is talking about the same thing.
When managers admit that there is no way to write a full specification
up-front, then they must admit that there is no way to build a full
design
up front either. UML style tools do not support the only methodology
that I
have ever seen succeed (outside of aerospace safety critical software
which
is a different issue). The only successful large software that I have
seen
succeed has been iteratively developed.
I don't think using UML has anything to do with the process you choose.
You can use an iterative approach with UML. UML is just way of
documenting design decisions, and should work with any process.
Having said that, I have no extensive experience with UML tools or
processes, only with the UML itself. I find the UML as good as any ML
for designing, but I can't comment on, for example, the Rational Rose
Software process, or whatever its called.
Drew McCormack
PS If you want a free UML tool, check out the java program ARGOUML. It
works quite nicely under OS X too!