Let’s say we have some class structure:

     public interface IA { public void doA(); }
     public class A implements IA { public void doA(){ System.out.println("A class doA");}
     public class B extends A { public void doA(){ System.out.println("B class doA"); }

And now in a main I state this:

     //in a main
     IA ia = new B();
     ia.doA();

Am I correct in stating that the the runtime object of ia is a B class and it has inherited all the super classes methods and attributes?

The printout from within the imaginary main is B class doA as the method doA in B will hide the same methods in its super classes?