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Sequence diagrams, the only good thing UML brought to software development

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Re: Sequence diagrams, the only good thing UML brought to software development

#81

Post by auggierose »

cubefox wrote: post #80
imiric wrote: post #31

I also find sequence diagrams to be the most useful, but disagree that the rest of UML is useless. Class, component, package, activity and state machine diagrams are all useful ways to model the structure and behavior of a system visually. The only reason the other diagram types fell out of favor is because of the development methodology change starting in the early 2000s. The industry started rejecting Waterfall, ea…

People who say "UML is useless" basically say "diagrams are useless". Which obviously isn't true. The alternative to UML is everyone inventing their own "diagram language" when they want to visualize something. Moreover, I think comparing different UML diagrams can also be enlightening for university students. E.g. state machine digrams look quite similar to activity diagrams, but the former emphasize states and the…

The nice thing about visual stuff is that it is self-explanatory. Instead of needing to read a book about UML first, maybe just use some prose in addition to your diagrams, and you don't need UML at all then. That's also more flexibel.

Re: Sequence diagrams, the only good thing UML brought to software development

#82

Post by TheCondor »

civilized wrote: post #13
Dig1t wrote: post #8

Spot on, I agree that sequence diagrams are super useful, I see them used all the time in FAANG. I do really wonder why UML is still taught in universities, as the article states, it's pretty useless. I took a masters Software Engineering course at Georgia Tech two years ago and a big part of the class was learning UML. That time was mostly wasted as I've never used any of it and never met anyone who has used it. It…

Why the university teaches outdated useless stuff? My guesses: - For the university, it fills out offerings and takes up credit hours, keeps the tuition dollars flowing - For the teacher, it's something they already know how to teach, so it doesn't require nearly as much effort to teach as something more useful but maybe less familiar - Universities are trusted with the decisions of what to teach and don't face much…

"Useless" is a strong word. Definitely a bit less useful than intended though.

Before UML, it's hard to capture the state of corporate software development that allowed the insanity to take part. I mean, UML was the marriage of two different approaches to drawing object models that were locked in a battle: OMT and Booch method. There weren't tons of open forums for discussion and debate like the internet has now, there were conferences and such and these guys were basically trying to create formal methods for objects in a vacuum.

It was kind of existential stuff for a lot of the smaller players in the industry, everyone saw value in this newer approach to building software. "Reusable components" seemed huge. Tooling was expensive, training was expensive. Microsoft was moving as a scary rate, connect your cart to the wrong horse and it could cost you the company... On some of the usenet forums, about the most open discussion there was at the time, I read debates about the virtue of C++ style multiple inheritance vs single inheritance and there were product matrices for programming tools that had check boxes for crap like that. C++ and CLOS both supported multiple inheritance so to the casual observer they were "better." Now I've never seen serious industrial software written in CLOS or anyone even considering it but it "had the features." It was just a different and crazy time, kind of amazing how open source/free/libre has altered things, the entire culture of building software is different and probably more healthy.

Anyone want to shit on design patterns next?

Re: Sequence diagrams, the only good thing UML brought to software development

#83

Post by preseinger »

RandyRanderson wrote: post #78

With any non-trivial set of messages, seq diagrams become unwieldy. Always use communication diagrams over sequence as a first choice.

to the contrary, the whole reason patterns like sequence diagrams are so great is because they make it clear when you're trying to put too much information into a single visualization

your "non-trivial" is my "too much"

Re: Sequence diagrams, the only good thing UML brought to software development

#84

Post by MockObject »

remote_phone wrote: post #55

I am thankful I managed to completely avoid both UML and J2EE in my career. Those embody the worst of so called Software engineering practices that I saw in my 30 years of working. It’s governmental bureaucracy embedded into technology that made it demonstrably worse.

J2EE hasn't been called that in 20 years. It's JEE now, and it's much nicer.

Re: Sequence diagrams, the only good thing UML brought to software development

#85

Post by esafak »

therealmarv wrote: post #57

I still remember of a professor in my university who has written also an UML book. He said it will be the most important thing in your software career and you will use it nearly daily in your future as software engineer. I was sceptical because it was too much preaching for my taste. Turns out I was right. 20 years later: I used it very seldom and definitely NOT in my daily software development tasks. Actually the se…

You're lucky if that was the most useless thing you learned. Many peoples' degrees were useless in their entirety!

Re: Sequence diagrams, the only good thing UML brought to software development

#86

Post by intrasight »

DaiPlusPlus wrote: post #50
tabtab wrote: post #36

Earlier quoted context omitted.

Can you give an example? Some try to put too much detail into ER diagrams in my opinion. A Data Dictionary is usually a better place for such details. ERD's should mostly be to illustrate relationships. One trend/fad was to put words describing links between tables, but I usually didn't find such helpful. Maybe if the wording was done well it would help, but most seem forced in practice. Good naming takes experience.…

> A Data Dictionary is usually a better place for such details. Self-documenting code/schemas are an even better place. ...sometimes I feel like I'm the only one in the world who uses DB-level metadata (e.g. `sp_addextendedproperty` in SQL Server) to attach explanatory notes and other metadata to database objects, including columns and constraints - and it gets better because I modified my Entity Framework scaffoldin…

>DB-level metadata

I've used it for years - usually auto-populated from the model that builds the relational schema (like you had done). Same for constraints. By coincidence, I just convinced my team to start using sp_addextendedproperty.

That's the advantage of using a higher-level notation, such as UML or code-first EF, for your ORM.

Good idea on the C# type naming conventions.

Re: Sequence diagrams, the only good thing UML brought to software development

#90

Post by talkingtab »

Sequence diagrams are outstandingly good and useful. I have a very complex set of interactions between two different servers involving user interfaces, back ends and server to server fetches (somewhat like Oauth but more). Using sequence diagrams to document this complex process helped me identify mistakes and allowed me to simplify the process. Highly recommended.
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