public class Circle extends GeometricObject implements Comparable<Circle> 
{
    private double radius;

    Circle(String c, double r)
    {
	super(c);
        radius = r;
    }

    public double getArea()
    {
        return 3.14159*radius*radius;
    }

    // The generics feature allows us to use Circle as data type ! 

    public int compareTo( Circle other )
    {
        double diff = this.getArea() - other.getArea();  

        return (int) Math.signum(diff);
    }

    public String toString()
    {
        return getColor() + " " + radius;
    }
}