Java Overload method with inherited interface

Question

i\'m trying to understand java behaviour. Using this interfaces :

public interface IA {}
public interface IB extends IA {}
public class myClass implements IB         


        

Answer 1

Because the compiler only knows that a is an instance of IA. Overloads are determined at compile time based on the compile-time types of the expressions involved, and the compile-time type of a is IA.

(Compare this with overriding, where the method implementation is chosen at execution time based on the actual type involved.)