Program to demonstrate inheritance

//Simple example of inheritance

//create a superclass
class A
{
    private int a;
    void showa()
    {
        System.out.println("a : "+a);
    }
}

//create a sunclass by extending A
class B extends A
{
    int b;
    void showb()
    {
        System.out.println("b : "+b);
    }
    void sum()
    {
        System.out.println("a+b : "+(a+b));
    }

}

class SimpleInheritance
{
    public static void main(String args [])
    {
        A superob=new A();
        B subob=new B();

        //the superclass may be used by itself
        superob.a=10;
        System.out.println("Contents of superob : ");
        superob.showa();

        //the subclass has access to all public members of its superclass*/
        subob.a=20;
        subob.b=30;
        System.out.println("Contents of subob : ");
        subob.showa();
        subob.showb();

        System.out.println("Sum of a and b : ");
        subob.sum();
    }
}

/*output
Contents of superob :
a : 10
Contents of subob :
a : 20
b : 30
Sum of a and b :
a+b : 50
Press any key to continue . . .
*/