CMIS 345
Week 5

Using either the Week 3 GeometricObject heirarchy classes
or your improved Week4 classes
write a program that makes an ArrayList of GeometricObjects.
Randomly (flip of coin) add Circles and Rectangles to it.
Ask the user how many objects to create.

Iterate or loop over the elements of the ArrayList using
a GeometricObject reference variable to point to each arraylist
element.  Notice that it can only access GeometricObject members
such as (implicit) toString, and the getters and setters of 
GeometricObject data members color, filled, and dateCreated.
To access the Circle or Rectangle object members a cast to that
class is needed. page 344-345

An ArrayList stores Objects (objects of the Object class that is
the superclass of all Java classes).
To be used polymorphically to store objects of your class heirarchy
you have to cast the 'getted' object to the top of your heirarchy:
GeometricObject geom;
...
geom = (GeometricObject)(geometricsArrayList.get(i));
Now geom can access the methods of an GeometricObject object:
color = geom.getColor();
System.out.print(geom );   //implicit toString()
but not the additional methods of Circle or Rectangle:
geom.getArea()    //syntax error: "cannot find symbol symbol  : method getArea()"
without a downcast to the subclass, first making sure the object is of that class:
if (geom instanceof circle)
  ...((Circle)geom).getArea()...