inside area of rectangle

abstract class figure
{
double dim1;
double dim2;

abstract double area();

void figure1(double a,double b)
{
dim1=a;
dim2=b;
}
}
class rectangle extends figure
{
rectangle(double a,double b)
{
super.figure1(a,b);
}
double area()
{
System.out.println("inside area of rectangle");
return dim1*dim2;
}
}
class triangle extends figure
{
triangle(double a,double b)
{
super.figure1(a,b);
}
double area()
{
System.out.println("inside area of triangle");
return (dim1*dim2)/2;
}
}
class absfig4
{
public static void main(String args[])
{
rectangle r=new rectangle(10,30);
triangle t=new triangle(10,50);

System.out.println("area of rectangle "+r.area());

System.out.println("area of triangle "+t.area());
}
}