ClassCastException

Question

i have two classes in java as:

class A {

 int a=10;

 public void sayhello() {
 System.out.println(\"class A\");
 }
}

class B extends A {

 int a=20;

 pub         


        

Answer 1

B extends A and therefore B can be cast as A. However the reverse is not true. An instance of A cannot be cast as B.

If you are coming from the Javascript world you may be expecting this to work, but Java does not have "duck typing".