when we use UML and when not? [closed]

Question

We know UML is unified modeling language. So does it can model any kind of software(like Linux kernel, open office, any web application, etc)? or only can model a software which uses Object Oriented language(Java, c++, etc)?

I think modeling is good way to figure out software. If we do not use UML for modeling, what other modeling methods can we use?

And do you know what kind of modeling methods is used for giant open source projects(Linux kernel, Openoffice.org, Firefox, Apache http, MySQL, Eclipse, VIM, etc) and where do we can find out the modeling documents of them?

Thanks any answers!

Answer 1

UML is first and foremost a communication tool, it helps you communicate ideas to other people on your team (or to yourself three months in the future), and as such, should be evaluated based on how easy it can express whatever you have in mind.

Being language-independent, UML cannot be used to express the expected, idiomatic way to use a given API or module, yet this is an essential part of the design: ignoring it can often end up with code that accurately models the underlying problem but requires dozens of lines of boilerplate code to interact with.

Also, UML cannot easily capture some specific properties of data structures that are relied on by algorithms. A red-black tree, for instance, is more easily represented by small tree-like sketches with "this is a red-black tree" or "this isn't a red black tree because" descriptions, than the corresponding UML class diagram.

Finally, languages may have features that are not represented elegantly in UML at all - for instance, Objective Caml module functors, or closures in any language that has them.