Overriding a super class's instance variables

Question

Why are we not able to override an instance variable of a super class in a subclass?

Answer 1

you can override a method,that is all right but what do you mean by overriding a variable? if you want to use a variable at any other place rather than super class u can use super. as in super(variable names); why do you want to override a variable? i mean is there any need?

Answer 2

If you have the need to override an instance variable, you are almost certainly inheriting from the worng class.

In some languages you can hide the instance variable by supplying a new one:

class A has variable V1 of type X;

class B inherits from A, but reintroduces V1 of type Y.

The methods of class A can still access the original V1. The methods of class B can access the new V1. And if they want to access the original, they can cast themself to class A (As you see dirty programming provokes more dirty progrtamming).

The best solution is to find another name for the variable.

Answer 3

Do you mean with overriding you want to change the datatype for example?

What do you do with this expression

public class A {
   protected int mIndex;

   public void counter(){
      mIndex++;
   }

}

public class B extends A {
   protected String mIndex; // Or what you mean with overloading
}

How do you want to change the mIndex++ expression without operator overloading or something like this.