CIS 260 Shape.java

Code

/*
    Shape.java
    CIS 260
    2005-02-09
    David Klick

    This is a demonstration of an abstract class. It is like
    any other class, except that it has at least one abstract
    (non-implemented) method. This class actually has two
    abstract methods, one from implementing the Drawable interface,
    and one of its own. Any classes which subclass this class must
    implement all abstract methods if objects are to be
    instantiated from them.
*/

abstract class Shape extends Object implements Drawable {
    private static int count = 0;
    protected Point origin = new Point(0,0);

    public Shape() { count++; }
    public Shape(int x, int y) { origin.x = x; origin.y = y; }
    public Shape(Point p) { origin.x = p.x; origin.y = p.y; }
    public void finalize() { count--; }
    public int getCount() { return count; }
    abstract public double area();
}