Which method is overridden? [duplicate]

Question

Class A has run() method and interface B also has run() method. Question is simple, which run() method is overridden in Main class and how will we prove this? Why there is no conflict (Compile-time error) in this code?

class A{     void run(){System.out.println("A class");} }  interface B{     void run(); }  class Main extends A implements B{     public static void main(String args[]){                  Main m = new Main();         m.run();     }      // Overridding method     public void run(){         System.out.println("run method");     } } 

Answer 1

run of A is overridden, run of B is implemented. As B is an interface, it only states how your objects behave to others and don't enforce any behavior itself.

Answer 2

run() Method of Interface B will be Implemented in class Main by overridden method of Class A.

Adding an extra point,

It you will not write the run() method in child class Main, You will not get well known "Unimplemented methods" error. This is true for public methods of class A for non public methods you will get compiler error : The inherited method can not hide public abstract method.

That is because methods of interface are public by default and you can not hide it with default (package private) access modifier.

Sample :

class A{     public void run() {         System.out.println("This method will be inherited.");     } }  interface B{     void run(); }  class Main extends A implements B{     public static void main(String args[]){                  Main m = new Main();         m.run();     } } 

OUTPUT : This method will be inherited.

In above code instance, the run() method is inherited from class A that will implement run() method of interface B.