how to reference a class which is extending a class and implementing an interface

Question

I have a class which is extending another class and implementing one interface , so now what will be the reference type of the class.As now I getting ClasscastException if I am trying to convert the base type into child type.

For example

public class Child extends Parent implements SomeInterface
{

}

SomeInterface childObject = new Child();
childObject2 = (Child)childObject;

or

Parent p = new Child();
childObject2 = (Child)p;

in both cases I am getting class cast exception

Answer 1

You can not cast the object of subclass to superclass.As superclass has generalized characteristics while subclass has special characteristics.

   SuperClass sup = (SuperClass) new SubClass();
   SubClass sub1 = (SubClass) sup;

You can refere : Casting super class to sub class