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When to Use a Factory Pattern

When to Use a Factory Pattern
You should consider using a Factory pattern when
· A class can’t anticipate which kind of class of objects it must create.
· A class uses its subclasses to specify which objects it creates.
· You want to localize the knowledge of which class gets created.
There are several similar variations on the factory pattern to
recognize.
1. The base class is abstract and the pattern must return a complete working
class.
2. The base class contains default methods and is only subclassed for cases
where the default methods are insufficient.
3. Parameters are passed to the factory telling it which of several class types
to return. In this case the classes may share the same method names but
may do something quite different.
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