resultdemo.java

我在学习JAVA的讲义

class A
{   public int x,y;
    A(int a,int b)
    {   x=a;
        y=b;
    }
    public void display( )
    {   int z;
        z=x+y;
        System.out.println("add="+z);
    }
}
class B extends A
{   B(int a,int b)
    {   super(a,b);
    }
    public void display( )
    {   int z;
        z=x*y;
        System.out.println("product="+z);
    }
}
class ResultDemo extends B
{   ResultDemo(int x,int y)
    {   super(x,y);
    }
    public static void main(String args[ ])
    {   A num1=new A(7,14);
        B num2=new B(7,14);
        ResultDemo num3=new ResultDemo(7,14);
        num1.display( );
        num2.display( );
        num3.display( );
    }
}