Okay, so, I’ve been messing around with this “law of segregation” thing in programming. You know, that whole “objects should only depend on the methods they actually use” idea. Sounds simple enough, right? But then I ran into this problem that totally threw me for a loop.
I was building this system for handling different types of users. We’ve got regular users, admins, and these special “guest” users. Each type needs to do different things, obviously. So, I thought, “Hey, I’ll make one big interface with all the methods everyone could ever need!” Yeah, that was my first mistake.
So I ended up with this huge interface, let’s call it UserInterface. It had stuff like readData(), writeData(), deleteData(), manageUsers(), you name it. Then, I made my different user classes implement this interface. RegularUser, AdminUser, GuestUser, the whole gang.
Here’s where things started getting messy. See, the GuestUser only needed to read data. They can’t write, delete, or manage anything. But because they had to implement UserInterface, I had to put empty methods in the GuestUser class for all those other actions. It looked ridiculous! Like, why have these methods if they don’t do anything?
- GuestUser had to implement:
- readData() – Okay, this one makes sense.
- writeData() – Nope, just an empty method.
- deleteData() – Another empty one.
- manageUsers() – You guessed it, empty.
The Fix
After staring at this mess for a while, it finally hit me. I was breaking the law of segregation! My classes were forced to depend on methods they didn’t even use. It was a lightbulb moment.
So, I scrapped that monster interface and made smaller, more specific ones. I created a Readable interface with just readData(), a Writable interface with writeData() and deleteData(), and a Manageable interface with manageUsers().
Then, I made my classes implement only the interfaces they actually needed. GuestUser just implemented Readable. RegularUser got both Readable and Writable. And AdminUser, well, they got the whole shebang – Readable, Writable, and Manageable.
It was like night and day! The code was so much cleaner and easier to understand. No more useless empty methods. Each class was only responsible for what it actually did. It just made sense.
So, yeah, that’s my little adventure with the law of segregation. It’s a simple concept, but it’s easy to mess up. Just remember to keep those interfaces small and focused, and you’ll be golden. Trust me, it’ll save you a lot of headaches down the road. And if you ever find yourself writing a bunch of empty methods, take a step back and rethink your interfaces. You might be breaking the law without even realizing it!
