OOP and the scope of a class, am I wrong?

[Steve Naidamast]

I always split my OOP classes into two parts; classes for actions, and structures\structs for data. I just find it easier that way. I also try to limit what each would hold in the attempt to keep my classes\structures small. In the end, OOP's big advantage is its organizational capabilities within an application. And that organization is primarily up to the developer, not a professor...

Steve Naidamast Sr. Software Engineer Black Falcon Software, Inc. blackfalconsoftware@outlook.com

[jochance]

#AdmiralAckbar It's a trap! Hopefully... he's gonna angle that into ok, that was a good start, but... sorta thing.

[megaadam]

The only reasonable thing I think the professor could have referred to is what Gerry Schmitz above (~3rd from top) referred to class TextReader which is not insane in the terms of GOF (Design Patterns) but Prof's way of describing it is ofc misleading. e.g.

class PngReader : public ImageReader {...

class SvgReader : public ImageReader { ...

"If we don't change direction, we'll end up where we're going"

[honey the codewitch]

Yeah, and this could have also been CsvReader except it only read a specific CSV with certain columns and datatypes. ReadTextFile is maybe the worst name I could think of for that. =) PatientDataReader would have been better.

Check out my IoT graphics library here: https://honeythecodewitch.com/gfx And my IoT UI/User Experience library here: https://honeythecodewitch.com/uix

[honey the codewitch]

I explained that while he should do as the assignment requires, a class encapsulates related data and actions, so it really was an inappropriate name for a class. I suggested another name "PatientDataReader" or something (I forget exactly, but it was better) if he was doing it on his own.

Check out my IoT graphics library here: https://honeythecodewitch.com/gfx And my IoT UI/User Experience library here: https://honeythecodewitch.com/uix

[MSBassSinger]

You are right. A class should represent some definable entity, whether atomically (e.g. Tire class) or in the aggregate of related entities (Car class that inherits Vehicle class, containing a Tire class collection, Engine class, Transmission class, etc.). Whatever "professors" that are saying what you report need to go get their hands dirty writing and supporting production software to test their theories before opening their mouths to sound foolish.

[Andreas Mertens]

You are right - someone will have to come along afterwards and clean this all up... :doh:

[StatementTerminator]

honey the codewitch wrote:

professors are teaching that classes are effectively a single action

That sounds like a method, not a class. Or a class with one method, which smells funny. Factoring OO is something that's taught in school, but not really understood until you get experience with it. Judgment calls have to be made. I've had to work with OO code that broke everything down into atomic classes. It was a nightmare to trace the code, and imagine what that does to the stack.

[honey the codewitch]

StatementTerminator wrote:

I've had to work with OO code that broke everything down into atomic classes.

To me that seems quite common these days in enterprise apps, almost as though someone made it by creating one extremely detailed UML diagram and then generating code from that. I've even seen many projects posted here that seem to overly factor. It does make it a nightmare to trace. I usually can't make much sense of code that's overly factored.

Check out my IoT graphics library here: https://honeythecodewitch.com/gfx And my IoT UI/User Experience library here: https://honeythecodewitch.com/uix

[jschell]

LOL. So I am not the only one.

[jschell]

I think I would rather read a PHD research article on string theory.

[jschell]

Keeping in mind of course that a school class is intended to teach concepts not practice. So in general one can think of it as a noun but if someone insists that every single class must always follow some rule about that then it is going to be a problem.

[jschell]

Perhaps the classes were really about teaching coding (mostly) and not about concepts? True it shouldn't be that way but it does happen.

[jschell]

Mark Quennell wrote:

where ReadTextFile inherits from (or implements) some sort of base Command class

Interesting possibility. Although then either the class should be an advanced one or specifically about patterns. Patterns should not be introduced in an introductory course.

[jschell]

Daniel Anderson 2021 wrote:

but the teacher is not necessarily wrong either

The teacher is wrong if the class is supposed to be an introduction of some sort. Especially if one is attempting to explain 'class' and 'methods'. One should not introduce advanced concepts until students have at least had the chance to master basics.

[jschell]

So then hypothetically and because you said elsewhere that it was copied... See the following. https://www.chegg.com/homework-help/questions-and-answers/using-java-programming-techniques-presented-fig-156-readtextfilejava-chapter-15-presentati-q57099852[^] In that there is nothing wrong with the 'class' being defined that way. Because it is main class in java. It is not a OO class but rather a specific type of java class. There appear to be other examples. I used the following to google.

programming assignment "class ReadTextFile"

[Tiger12506]

I would say that you are 100% correct. The weirdness started when languages and frameworks started making unreasonable demands of the analogy. Take, for instance, Java's everything is a class, even when it's not.. or the concept of microservices, where essentially every method is wrapped in a class because it is a self-contained unit. I think the weirdness stems from these scenarios and pollutes design spaces where it shouldn't.

[raddevus]

honey the codewitch wrote:

It was an assignment, I think photocopied out of a book

So, that means the Professor is just a willing purveyor of tripe who does not take the time to determine if the materials she uses have any value. Also, it means that the Professor is not the root cause of the problem -- just the purveyor. Which, in turn means... We need to get that book and destroy it. :laugh: I'd love to know the title of the book which has : 1. bamboozled the professor 2. is chosen by universities 3. is spreading lies about OOP :rolleyes:

[honey the codewitch]

Keep in mind, I don't know for sure. I saw a snapshot of a printed assignment, or maybe it was a book. Like I said, I didn't ask. Jschell did some googling and found that other people made a class with that name. I'm pretty sure the prof adapted the assignment somewhat for his class though, for reasons.

Check out my IoT graphics library here: https://honeythecodewitch.com/gfx And my IoT UI/User Experience library here: https://honeythecodewitch.com/uix

[Roger Wright]

Last time I was a paid programmer the concept of OOP was brand shiny new; they never mentioned it in school. The first I heard of it was in a night class at TRW on Ada, the DoD's latest answer to everything data. It was fascinating but extremely difficult to get a grip on the concepts, since most of us cut our teeth on FORTRAN and COBOL. My training and experience using it (I was in heaven when Turbo Pascal 5.5 introduced OOP to that perfect language) matches your understanding exactly. Over the years I've heard people redefining it, but I think you've nailed it. I still remember the first satisfying moment when I realized that a Class defined an Object, and objects were created by instantiating the Class. That's a hard one for an old (probably 30 yo by then) procedural programmer. :laugh:

Will Rogers never met me.