View Full Version : سوال: مفهوم Client/Supplier Roles of Associations

پنج شنبه 11 فروردین 1390, 14:26 عصر

من این مطلب رو تو مهندسی نرم افزار پیدا کردم ، ولی مفهوم اون رو متوجه نمی شم ، اگه ممکنه توضیحاتی رو که می دونین اینجا بزارین .
این عبارت هم یعنی چی ؟ Navigability

این متنی است که منظورش رو متوجه نمی شم .

The rules regarding the client and supplier roles of associations are listed in their order of precedence:

· If an association is an aggregation, the diamond end is the client. Navigability on either end of the association will not affect the client role of the aggregation. For instance, the diamond will still be the client if you set both ends to "not navigable" or if you set the end with the aggregate diamond to an arrowhead. The diamond will take precedence to navigability if there is at least one end is not navigable.

· The end opposite to the aggregation diamond in an aggregation association can act as a client if it can navigate to the end with the diamond. This does not contradict the first rule because the item connected to the end opposite to the diamond can navigate to the diamond and, therefore, it is a client by definition.

· If the association is not an aggregation, then the navigability will determine the client and supplier end. For a uni-directional association, the client is the end opposite to the arrowhead and the supplier is the end with the arrow. For a bi-directional association, either end can be both client and supplier at the same time.

· An association can be both a client and a supplier at the same time subject to the
restrictions mentioned in the first three rules.

· If the association is not an aggregation and both ends are not navigable, it is neither a client nor a supplier."