/**
   A square with a base point and side.
   @author Greg Vogl
   last modified 2003-10-14
*/
public class SquareShape extends Shape
{
   // constructors
   // override defaults
   public SquareShape() { super(); side = 1; }
   public SquareShape(double x, double y) { super(x, y); side = 1; }

   // additional constructors
   public SquareShape(double side) { super(); this.side = side; }
   public SquareShape(double x, double y, double side) 
   { 
      super(x, y); this.side = side; 
   }

   // accessors
   public double side() { return side; }

   // calculations
   public double perimeter() { return 4 * side; }
   public double area() { return side * side; }

   // toString
   public String toString()
   {
      return super.toString() + "[side=" + side + "]";
   }

   // private variables
   private double side;
}