Re: Is a static method sufficient to call it factory?



f.vivoli@xxxxxxxxx wrote: 
Hi everyone,

I've just a doubt...

Talking about factories why someone propose the way

Factory.getInstance().createClass(aType);

instead of simply

Factory.createClass(aType);

That is,
why the singleton?

In the end, is a class with a static method eligible to be an use of a
factory method pattern? It doesn't resemble the structure of the GOF
pattern, since it doesn't use subclassing...

Actually, one of the reasons to use a singleton is that the getInstance method can return a subclass. So some subclassing is really used, which makes it more similar to a factory method.
Looks a bit strange implementation, though. The singleton should always return the same instance, whereas the factory patterns are made to work with more subclasses.
.

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