Stage 1 + Advanced language based _1-3-Java language inheritance and polymorphism advanced _02- Section 7 _ _17_ interface as an internal class method parameters and return values or

As the interface method parameters and return values


ArrayList point went to see the source code

and then point to go see List <E> source

we have learned a number of states, you can use the left and right sub-parent




interfaces here again as a parameter and as the return value