Direction of the association arrow in UML class di

2019-01-25 10:51发布

On this webpage which shows how to draw a class diagram, why is the arrow for association pointing from order to customer, and not from customer to order?

UML Tutorial - Class Diagrams

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趁早两清
2楼-- · 2019-01-25 11:39

It's a dependency, which is a special weak type of association. It means that for an order to exist, there must exist a customer at some point in time. There may be some point in the lifecycle of "order" where this requirement is not enforced.

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