Java interfaces override method

Question

please explain why? can't find any good source

interface ABCD {
    default void print() {}
    static void print_static() {}
}

interface B extends ABCD{
    static void print() {}//error, why?
    default void print_static() {}//fine, why?
}

Answer: @AdolisPali Becase the default method print is inherited from ABCD, so it's in interface B too. And you can't have a static method in that interface with the same name and arguments – fps

Because you are trying to override a non-static method with a static one. Which is what the error message is telling you. — f1sh
– f1sh, Commented Sep 23, 2020 at 17:11
Static methods can not be overridden in the exact sense of the word. It's static — Chargnn
– Chargnn, Commented Sep 23, 2020 at 17:14

Kuldeep Jain · Accepted Answer · 2020-09-23 17:19:02Z

2

You cannot override the static method of the interface; you can just access them using the name of the interface. If you try to override a static method of an interface by defining a similar method in the implementing interface, it will be considered as another method.

See this: https://www.tutorialspoint.com/default-method-vs-static-method-in-an-interface-in-java#:~:text=You%20cannot%20override%20the%20static,static)%20method%20of%20the%20class.

Essentially in Java, the keyword static indicates that the particular member belongs to a type itself.

edited Sep 23, 2020 at 17:19

answered Sep 23, 2020 at 17:15

Kuldeep Jain

8,6388 gold badges54 silver badges80 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Chargnn Over a year ago

To add a bit more: You can overload static method.

Adolis Pali Over a year ago

still not clear, if static methods belong to interface so why B interface can't have static void print() {}

fps Over a year ago

@AdolisPali Becase the default method print is inherited from ABCD, so it's in interface B too. And you can't have a static method in that interface with the same name and arguments

Ferry · Accepted Answer · 2020-09-23 17:51:32Z

1

Every instance method automatically inherits to their sub classes and only can be overridden by instance method from their sub classes too. Static method can not override instance method. Thus in your case, method "default void print_static()" from ABCD doesn't override "static void print_static()" from B. You still can call ABCD.print_static() for ABCD and print_static() for B.

answered Sep 23, 2020 at 17:51

Ferry

4144 silver badges10 bronze badges

Collectives™ on Stack Overflow

Java interfaces override method

2 Answers 2

3 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related