manage polymorphic class persistency

"Fei Liu" <>
28 Jun 2006 06:33:52 -0400
Creational patterns such as prototype, factory method, abstract factory
often require that object creation in a somewhat hardcoded way. For
example, in creating a system where a hierarchy of objects need to be
saved and restored to/from persistent storage:


A bruteforce approach to restore from persistent storage would be
something like this

class ShapeFactory{
    static Shape * CreateShape(char tag){
               'C': return Circle.CreateCircle();
               'S': return Square.CreateSquare();

class Circle{
        static Circle * CreateCircle(){ return new Circle(); }

What's shown here is a factory method design pattern. My question is if
there is a better (or standard) way to solve this problem. Thank you!

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