Monthly Archive for September, 2007

Aggregation Aggravation

In the first installment of this Flyweight Saga, I noted that the relationship between a Flyweight and Flyweight Factory class is one of aggregation. The initial example shows that the Retrieve method in the Factory class returns an instance of IFlyweight, meeting the requirement of the proper connection between the two classes. In looking at one example in Java, (even with modest Java skills), the program clearly did not have such a relationship between the Factory and Flyweight. In fact, it claimed, that an object’s extrinsic state can be shared by classes. Now, maybe that was unfortunate wording because the big feature of the Flyweight design pattern is that the Flyweight can be a shared object, but only the intrinsic state can be shared. (Maybe the author meant that extrinsic states can be shared between classes in a Flyweight design pattern, and that’s probably right but is not a key feature of the pattern.)
Continue reading ‘The ActionScript 3.0 Flyweight Saga: Part III Aggregation Aggravation, Stuff on the Stage and the Intrinsic State’