/**
 * Base class for all Shapes, containing basic geometry common to all
 * shapes. A starting point for extension by other classes.
 * @author wokoun
 */
public abstract class Shape
{
  /** Maximum value */
  public static final double UPPER_BOUND = 1000.0;

  /** X-coordinate of the shape */
  private double x;
  /** Y-coordinate of the shape */
  private double y;

  /**
   * Construct a new shape instance
   * @param x X-coordinate, must be between 0 and 1000
   * @param y Y-coordinate, must be between 0 and 1000
   * @throws IllegalArgumentException if a parameter causes the shape to extend
   * out of bounds
   */
  public Shape(double x, double y)
  {
    setX(x);
    setY(y);
  }

  /**
   * Get the X-coordinate
   * @return X-coordinate, between 0 and UPPER_BOUND
   */
  public double getX()
  {
    return this.x;
  }

  /**
   * Set the X-coordinate
   * @param x X-coordinate, must be between 0 and UPPER_BOUND
   * @throws IllegalArgumentException if a parameter causes the shape to extend
   * out of bounds
   */
  public void setX(double x)
  {
    if (x < 0.0)
      throw new IllegalArgumentException("X cannot be less than zero");
    if (x > UPPER_BOUND)
      throw new IllegalArgumentException("X cannot be greater than " + UPPER_BOUND);
    this.x = x;
  }

  /**
   * Get the Y-coordinate
   * @return Y-coordinate, between 0 and UPPER_BOUND
   */
  public double getY()
  {
    return this.y;
  }

  /**
   * Set the Y-coordinate
   * @param y Y-coordinate, must be between 0 and UPPER_BOUND
   * @throws IllegalArgumentException if a parameter causes the shape to extend
   * out of bounds
   */
  public void setY(double y)
  {
    if (y < 0.0)
      throw new IllegalArgumentException("Y cannot be less than zero");
    if (y > UPPER_BOUND)
      throw new IllegalArgumentException("Y cannot be greater than " + UPPER_BOUND);
    this.y = y;
  }

  /**
   * Calculate the area of the shape
   * @return Area in square units
   */
  public abstract double area();

  public String toString()
  {
    return "area=" + area() + ",x=" + this.x + ",y=" + this.y;
  }

  public static void main(String[] args)
  {
    Ellipse e = new Ellipse(10.0, 50.0, 75.0, 110.0);
    System.out.println(e);
  }
}