public
class Circle extends Shape {
protected double r;
public Circle(double r) { this.r = r; }
public Circle() { this(1.0); }
public double area() { return Math.PI*r*r; }
public double circumference() { return 2*Math.PI*r; }
public double getRadius() { return r; }
}
public class Rectangle extends Shape {
protected double w, h;
public Rectangle(double w, double h) { this.w = w; this.h = h; }
public Rectangle() { this(1.0,1.0); }
public double area() { return w*h; }
public double circumference() { return 2*(w+h); }
public double getWidth() { return w; }
public double getHeight() { return h; }
}
Aufruf:
public static void main(String[] args){
Shape[] aShape = new Shape[2];
aShape[0] = new Circle (2.0);
aShape[1] = new Rectangle (1.0,2.0);
double area = 0.0;
for (int i = 0; i < aShape.length; i++)
area += aShape[i].area();
}
