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Use Cases: Pertaining to the Project

So last time we covered the really high level theory behind use cases and why planning them is kind of important when writing a program. This is the part where I tell you I've changed my mind, I'm just going to totally wing this project since I landed an internship and I don't actually need this program to be professional looking.

Use case diagram for the student actor
PSYCH--did you even read how I closed the last post?

That was hilarious. But anyway. I didn't actually go through the full CSCI-1275 "discovering your use cases through '20 Questions,' rune reading, and chasing clients for interviews" approach. We spent close to a month on use cases in that class--how to identify them, how to define them, how to model them, and a little on how to prioritize them. The bulk of the class was use cases, and like I said...I get it now.

But that doesn't mean I'm doing to sit and actually write out a full CRUD technique analysis of all the ways a single user will interact with a single function app. I did it the old fashioned way, with a cup of coffee and my imagination.
Imagine yourself a college student setting up this app. What do you do?
Well, I'll need to set up an account. Which means I'll need to set a username, my e-mail, my password, and probably my school. All use cases, in their own way--ways the student will use the system.
Now you have an account, and you need to know if you can pull an A in Dr. B's class. What do you do?
This is where it starts getting trickier, and I have the advantage of having mapped a lot of this the hard way in the console application. I'm going to need to create a course, which means setting the course name, the instructor, the course number, the credit hours, and the grade type.

I could keep going on this--the create grade type use case is ALSO made up of several use cases, and so on. The diagram explains. It also helps lay out the flow of the program to some degree, or at least makes it easier for me to visualize...more on that later.

A moment for disclaimers--I don't claim to have UML as a strong skill, and it's thoroughly possibly I've misused the "extends" vs "includes" or even the term use case isn't right on. My goal with documentation isn't 100% technical accuracy, as long as I'm close enough that a third party can look at what I did and go "I see what you did there!"

The goal here is the high level blueprint of what the program needs to do--the road map that guides the rest of the planning phase, which is what I'm about to start on today. This is where we head into the weeds...
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