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What about the much maligned factory pattern

If classes are first-class variables (as in Python, and now even Java (I think)), this is replaced with a constructor which takes a class as an argument.




Then you aren't gaining anything over simply calling 'new' on that class, negating the point of the factory pattern, right?


The point of the factory pattern is that you don't always want a new instance, and you don't always want a specific type. "new Foo()" necessarily does both, while Foo.new() can potentially do neither.


Java has always had the ability to reference Class types, and, to instantiate instances of that type using a standard method:

Object makeOne (Class fooClass) { return fooClass.newInstance(); }

You are missing the point of a factory pattern, which is informed by the non-accidental pattern name: 'Factory'.

[edit: using generics it is even type safe]: <T> T makeOne (Class<T> clazz) { return clazz.newInstance(); }




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