What are wildcards in generics?

What are wildcards in generics?

Wildcards in generics are a way to specify an unknown type. They allow for more flexible and reusable code.

Can you give me an example of how to use wildcards?

Sure! For instance, in Java, you can use <?> to represent an unknown type in a method that accepts a list of any type.

What’s the difference between upper and lower bounded wildcards?

Upper bounded wildcards (e.g., <? extends T>) restrict the unknown type to be a subtype of T, while lower bounded wildcards (e.g., <? super T>) restrict it to be a supertype of T.

When should I use wildcards instead of specific types?

Use wildcards when you want to write more general code that can work with different types without being overly specific.