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## 2006/06/29

### 爆氣

... In your use case work, don't put too much effort into the diagram. Instead, concentrate on the textual content of the use cases.

The best way to think of a use case diagram is that it's a graphical table of contents for the use case set. ...

... The UML includes other relationships between use cases beyond the simple includes, such as <<extend>>. I strongly suggest that you ignore them. I've seen many situations in which teams can get terribly hung up on when to use different use case relationships, and such energy is wasted. Instead, concentrate on the texual description of a use case; that's where the real value of the technique lies. ...

... The more I see of use cases, the less valuable the use case diagram seems to be. With use cases, concentrate your energy on their text rather than on the diagram. Despite the fact that the UML has nothing to say about the use case text, it is the text that contains all the value in the technique. ...

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