Generic extend can't add the same type

Question

I\'m new to these generic types. In the below code, I created a method that accepts a List of items that extends \"String\".

My Question? - When the list can be assigned

Answer 1

When you have a variable with a wildcard, and a method that takes the generic type parameter, Java cannot ensure type safety. It must disallow this call.

Consider a List for example. You may have assigned it List, but the variable could be assigned a List. You shouldn't be allowed to add a Dog to such a list.

To allow the add method to be called, remove the wildcard.

public void takeList(List list){

Besides, String is final, so there really is no point to saying ? extends String.