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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

#61

Post by manbash »

I consider myself an advocate of sequence diagrams (of all other UML diagrams), so I wonder why the article doesn't mention that this type of diagrams is meant to depict testable flows the software components.

It's nice and all that you can clarify to your team what you want to gain (the big picture), and it's also nice if you want to explain how (details), but in my opinion it's not worth much if your sequence diagram doesn't explain test cases clearly and expect for them to be written.

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

#62

Post by [deleted] »

ivan_gammel wrote: post #34
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…

Every software engineering team in my 20+ years career actually used 2-5 types of UML diagrams: classes, sequences, deployment, activity, state. I think it mostly depends on maturity of the team and engineering culture, whether UML is used or not. There’s certainly some value in it.

[deleted]

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

#63

Post by zabzonk »

pydry wrote: post #37
zabzonk wrote: post #27

UML is completely crap as a design language. But it can sometimes be useful as a documentation language.

It's crap at that too. It was an excuse to sell rational rose. It doesn't need to be excused.

i agree that rose was crap. but some other tools, such as enterprise architect were not so bad, despite the name. and the ent arch guys were always very helpful. this would be something like 20 years ago - gosh.

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

#64

Post by rvbissell »

baudaux wrote: post #23

Plantuml is a really convenient tool for drawing diagrams

I yearn for something that lets me draw sequence diagrams as human-readable ascii art (instead of declarative statements as with PlantUML,) but that is also rigorous enough to be rendered to a professional looking PNG when the situation requires it.

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

#65

Post by duped »

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…

There's a bureaucratic reason too. Changing curricula is not fast and can take years (depending on the institution of course).

My department profs actually got in a bit of trouble with the university because they took the course that they should use for undergrad/graduate mentoring (something like a "special studies in XXX" placeholder, usually for independent or small group study that was special enough for course credit) and used it to create their own courses outside the review of approving a new course with a distinct number and credit count.

The reason they did it in the first place was because if they wanted to change the curricula for the existing courses, remove course numbers, or create new ones, the bureaucracy would take 4-8 semesters to get approval and complete. By which time some of the material was obsolete. One of the profs got fired and the rest quit, eventually.

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

#66

Post by Dig1t »

anonzzzies wrote: post #22
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…

> I see them used all the time in FAANG. Does that mean something? Besides you saying you worked in them? It’s a question ; I don’t know.

It is shorthand for saying that it is used by engineers working on high-profile, high-impact, software that ships to hundreds of millions of people. Some people might argue that these teams work on some of the most important software in the world. So if the people who work on this important software do a thing, like use sequence diagrams, that is a decently good signal that the thing is useful.

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

#67

Post by Kon-Peki »

gumby wrote: post #52

I don't really see them as an advance on the century old flow charts.

The flowcharts (that I've seen) don't do a good job of capturing who does what in the process, whereas sequence diagrams do.

Side note - my father, during his career, had a huge collection of flowchart stencil sets that he used; I really wish that I had a chance to grab them.

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

#68

Post by atribecalledqst »

readthenotes1 wrote: post #45

Sequence diagrams were not original to UML. Sadly, I cannot remember the method they stole it from. I do remember it was created by a man working for Hewlett-Packard in Britain who published a book around 1993. Does anyone remember?

TCP/IP Illustrated by W. Richard Stevens has sequence diagrams, although that book dates to 1994 which is right around the time UML was originally being developed. So, it's not a strong data point.

I'm positive you're right that sequence diagrams existed independently of / prior to UML though.

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

#69

Post by marcosdumay »

ivan_gammel wrote: post #34
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…

Every software engineering team in my 20+ years career actually used 2-5 types of UML diagrams: classes, sequences, deployment, activity, state. I think it mostly depends on maturity of the team and engineering culture, whether UML is used or not. There’s certainly some value in it.

I don't think I have ever seen anybody actually getting value from a class diagram. I have seen many people creating them, but they are always useless.

I also don't think the UML variant of state machines and workflow are any popular. But well, there is probably somewhere where people use them. Also, those lists usually ignore entity-relationship diagrams, where UML just adopted the popular format (without even minor changes, like for workflows), and thus everybody uses the UML one.

But yes, people don't remember about deployment diagrams. Those are used a lot.

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

#70

Post by smusamashah »

https://sequencediagram.org/ is the best text-to-sequence-diagram tool. Its the only one of these which lets you draw sequence diagram with your mouse too and will generate text accordingly. Completely offline (localstorage) and also supports saving to onedrive and google drive.
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