Enthuware

Hello ,
Regarding option 1 , why you considered interfaces to be always abstract ?
Currently with java 8 , they could have a default method which is non-abstract methods so interfaces behalves current with implementation.

Kindly clarify.

Yes, an interface may have default and static methods. But that doesn't mean it is not abstract. You still can't instantiate an interface precisely because it is abstract.

You can think of it like an abstract class that has some methods implemented. Just because an abstract class has some method implementations doesn't mean it is not abstract anymore.

HTH,
Paul.

Thanks for your answer.

According to this Oracle's page https://docs.oracle.com/javase/tutorial ... tance.html :

"Default methods introduce one form of multiple inheritance of implementation. A class can implement more than one interface, which can contain default methods that have the same name. The Java compiler provides some rules to determine which default method a particular class uses."

So, wouldn't it make option D correct?

You are right. It it indeed one form of multiple implementation inheritance. The only thing that is not allowed is multiple inheritance of the same method. Fixed.
thank you for your feedback!
Paul.