// typeinfo/Shapes.java // ©2015 MindView LLC: see Copyright.txt import java.util.*; abstract class Shape { void draw() { System.out.println(this + ".draw()"); } @Override abstract public String toString(); } class Circle extends Shape { @Override public String toString() { return "Circle"; } } class Square extends Shape { @Override public String toString() { return "Square"; } } class Triangle extends Shape { @Override public String toString() { return "Triangle"; } } public class Shapes { public static void main(String[] args) { List shapeList = Arrays.asList( new Circle(), new Square(), new Triangle() ); for(Shape shape : shapeList) shape.draw(); } } /* Output: Circle.draw() Square.draw() Triangle.draw() */