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Q) What is the output of the fallowing program?




class A
{
}     
class B extends A
{
       void x()
       {
              System.out.println("method x");
       }//child specific behaviour.
}
class test
{
       public static void main(String args[])
       {
              A a=new B();//super class reference referring to sub class object.
              a.x();
       }
}

A)
The above program causes compilation error.
->child specific behavior means that method behavior should not contain in super class.
->only overridden methods are called by super class reference which is holding the address of child class.
->even though super class reference can refer to the sub class object. Using class reference child specific (non-overriding) methods can’t be called. In the above example “x()” is not overriding method.

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