Program to find area of Rectangle in java

abstract class Figure
{
double dim1;
double dim2;
Figure(double a, double b)
{
dim1=a;
dim2=b;
}
abstract double area();
}
class Rectangle extends Figure
{
Rectangle(double a, double b)
{
super(a,b);
}
double area()
{
System.out.println("Area of Rectangle");
return(dim1*dim2);
}
}
class Triangle extends Figure
{
Triangle(double a, double b)
{
super(a,b);
}
double area()
{
System.out.println("area of triangle");
return(dim1*dim2/2);
}
}
class AbstractArea
{
public static void main(String args[])
{
Rectangle r=new Rectangle(10,5);
Triangle t=new Triangle(10,2);
Figure figref;
figref=r;
double d1=figref.area();
System.out.println(d1);
figref=t;
double d2=figref.area();
System.out.println(d2);
}
}