[vwnc] Instantiation of Abstract Class Random

Open a base 7.6 image and browse references to class Random. At least
three places "Random new" is performed. This is incorrect (design) as
Random is an abstract class. See message #nextValue which defines a
subclass responsibility.

The instantiation does not lead to any problems, but the fact that the
class is marked as abstract (by sending #subclassResponsibility) means
cleanup is necessary. I suggest FastRandom is used instead, or that
#nextValue sends #shouldNotImplement instead of
#subclassResponsibility .

Runar Jordahl
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Runar,

the implementation and usage is correct!

Random new is a factory method, calling ^self defaultGeneratorClass new

Being abstract does not rule out class side methods that delegate to
appropriate subclasses. At no time, Random instances are created.

Andreas


Am 24.07.2008 9:58 Uhr schrieb "Runar Jordahl" unter
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I see and agree.

We have a unit test that traverses our code looking for sends of #new
to classes that are abstract. I guess I need to add Random as an
exception where sending #new is OK.

Runar
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