public class GeometricObjectDemo {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Circle cake1 = new Circle(2);
		Square cake2 = new Square(3.5);
		System.out.println(cake1.getArea());
		System.out.println(cake2.getArea());
		System.out.println(cake1.compareTo(cake2));
	}

}
abstract class GeometricObject implements Comparable{
	String name;
	Date dateCreated;
	abstract double getArea();
	public int compareTo(Object other){
		double thisArea = this.getArea();
		double otherArea = ((GeometricObject) other).getArea();
		if(thisArea < otherArea){
			return -1;
		}
		if(thisArea > otherArea){
			return 1;
		}
		return 0;
	}
}
class Circle extends GeometricObject{
	double radius;
	Circle(double rad){
		radius = rad;
	}
	double getArea(){
		return radius*radius*Math.PI;
	}
}
class Square extends GeometricObject{
	double side;
	Square(double s){
		side = s; 
	}
	double getArea(){
		return side*side;
	}
}