12 Essential Skills for Software Architects - UML

Hi Dave,
The last few years with the rise of Agile has seing the decline of UML. I still think UML is very important as a way of expressing ideas (rather than as a blueprint for code), but sadly a lot of organisation just don't use it at all and design quality suffers. What's your view on it?
Thanks.

Hi Luke,

I personally like UML and use it regularly. It's a great way to visualize information about structure and sequence.

Nearly every project I work on is agile - I still need to take time think through the problem at hand - UML helps me with this.

I usually only produce what is needed at the responsible time (sometimes only on white boards) versus creating volumes of diagrams that may or may not get used.

Thank you for the question!

Dave Hendricksen wrote:Hi Luke,

I personally like UML and use it regularly. It's a great way to visualize information about structure and sequence.

Nearly every project I work on is agile - I still need to take time think through the problem at hand - UML helps me with this.

I usually only produce what is needed at the responsible time (sometimes only on white boards) versus creating volumes of diagrams that may or may not get used.

Thank you for the question!

Good answer. I think one reason why there has being a demise in UML is because the lack of a very good free tool. There are some good ones at very good prices but people are starting to expect free versions of everything.

I've seen the opposite situations in recent projects, where the use of a very heavy RUP-like approach to agile development has encouraged people to produce huge numbers of UML documents (mostly because they can) which are laboriously maintained in Rational tools but otherwise never looked at again. Meanwhile, the actual developers are still working to "lite" agile timescales and end up having to work around, rather than from, the avalanche of UML documentation.

Whatever the perceived benefits of UML (and it's not particularly useful for heavily data-centric systems e.g data warehousing), I have the impression it has sometimes tended to encourage this kind of displacement activity, where people regard the UML diagrams as products in themselves, rather than simply as a mechanism to help create the real product.

chris webster wrote:I've seen the opposite situations in recent projects, where the use of a very heavy RUP-like approach to agile development has encouraged people to produce huge numbers of UML documents (mostly because they can) which are laboriously maintained in Rational tools but otherwise never looked at again. Meanwhile, the actual developers are still working to "lite" agile timescales and end up having to work around, rather than from, the avalanche of UML documentation.

Whatever the perceived benefits of UML (and it's not particularly useful for heavily data-centric systems e.g data warehousing), I have the impression it has sometimes tended to encourage this kind of displacement activity, where people regard the UML diagrams as products in themselves, rather than simply as a mechanism to help create the real product.

I think that happens when UML is used as a blueprint rather than as a form of communication.

Requirements keep on changing everyday. I think it is a waste of effort to draw UML and people complain that diagram is not updated. Maybe it would good idea to create after releases.

Pradeep bhatt wrote:Requirements keep on changing everyday. I think it is a waste of effort to draw UML and people complain that diagram is not updated. Maybe it would good idea to create after releases.

I agree. If someone tries to model a project with 100's of sequence diagrams - that is an absolute waste of time.

But if you are trying to explain an idea for a design, or an architecture than UML is a must. It features heavily in the Java EE architects exam.