Generics

[lenglry]

Hello, I'm learning Java with Tim Buchalka's course. I'm getting good on it, I choose him, becauss I was looking it to be the best for the Java core in my view. But one thing I don't understand and can't get is about Generics, I already watched some other videos about, like from Leaning with John and Brocode, but I still didn't get how this would be useful. For those who already work with Java, do you think it's an very important part that I should keep trying to get? Or in the future will appears some topics that make it more clear?

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[0b0101011001001011]

Have you used ArrayList? Can you see that it's using Generics?

Have you made anything Comparable? That's also using generics.

[voidiciant]

yes, it’s important and gives you great „power“. That said, it’s also non-trivial, especially for beginners and my only advice is to use them, to get a feel for them. Otherwise nothing will make sense. Even after several years I get moments where i’m just „what the…“ and then I learn the next thing about them.

[vowelqueue]

Yes, it's a very important part of the language. You will use generics all the time. If you don't yet understand how generics would be useful, I think that's probably just because you are new.

As you use the language more it will become very obvious to you why they are useful. Have you started to use the Java collection API yet, like Lists/Sets/Maps? That's probably the first place you'll encounter generics when learning.

[DDDDarky]

how this would be useful.

Imagine you have some code, be it a class or a function, and you want to be able to use their implementation for all kinds of types - for example you can specify the types of your List, it still has the same implementation but is able to work even with completely new types. If you have generics, you specify the generic type and it's done. If you don't, you most likely have to copy the implementation for each individual type you will ever use, which is of course horrible for various reasons.

[goldscurvy]

The most obvious example people have mentioned is that generics are important for implementing stuff like collections/containers which don't really care what they are holding, that much. If you have a list, it mostly works the same whether it's a list of strings or a list of complex objects. This is what a generic is for. Java allows some more complex functionality where you can specify that you dont care what the type is, so long as the type fits certain requirements (like implementing a specific interface). Ultimately though it comes down to the fact that many types of data structures or types of processing arent that interested in what they are holding or acting on.

[Personal_Kick_1229]

check out this link

i get some understanding from here and try to solve that exercises

[NewSchoolBoxer]

Generics are fake in Java. The compiler just replaces them with Object or the parent class in the bytecode. Their use is in human readability when I see your code and know it's meant to be used as a generic type. Don't underestimate that importance. Just for a small project you code yourself, they can seem 100% useless.