The third big issue was about the UML. Everywhere I went, people were struggling with it, and I think the repetition of that confusion finally made me take a hard look at it. The UML is not only too complex, it seems to be incomplete (or at the very least, it takes far too many kinds of diagrams to express the design).
The reason for the complexity of the UML is, ironically, inappropriate mixing of abstraction levels. I'm certain this happened because, back when Rational was a viable company (before too many people asked "if Rational is supposed to teach us how to create good software, how come Rose is such a bad piece of software" and the company imploded, being "saved," if you can call it that, only because IBM bought them as they were spiraling down the drain), and they brought Booch, Jacobsen and Rumbaugh together so they would stop fighting and create a "Unified" model (the creation of peace was the reason for the "U", for those of you new to the story). When this happened, agendas inevitably got mixed together, and I suspect that Rational had its own agendas which got into the mix, design-by-committee style. At the time, C++ was king of the OO languages so you see a lot of C++-isms in the UML, which introduced innapropriate details. At least one player appeared to have grand ideas of taking this abstraction tool and giving it enough detail to produce code. Of course, we see this in most of the modeling tools, which can spit out framework code from the UML, but in recent years the spectre of Model-Driven Architecture (MDA) has appeared, which was probably inevitable given the implied promise that someday UML would be the one ring that binds them all. Fortunately, the MDA experiments seem to be happening in the open-source world, so we can discover (again) that programming-by-drawing-pictures is Goedel-incomplete, without having to pay hundreds of thousands for tools that don't work hawked by vendors selling faith-based solutions, as has been the case for every "revolution" that has popped up in the past.
Because of all these misdirections, it's no wonder people get confused about what to do with the UML. Is it for modeling, or is it for detailed design? My guess is that forces within Rational wanted it to be everything to everyone, but this goes back to my original point: a method must be really, really simple in order for people to use it without getting lost.
http://www.artima.com/weblogs/viewpost.jsp?thread=115101
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... mi sembra un po' esagerato ... sono tanti i progetti in cui UML ha trovato una felice applicazione, dico questo lungi da me la volonta' di nasconderne i limiti, che in parte Eckel ha centrato ...
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