Use case diagram Provides a behavioral view of system context by displaying actors external to the system who go to the system to achieve a specific, valued result (use case).
用例图通过向即将使用系统的人员提供一个系统背景的行为性视图，来取得一个特定有价值的结果(用例)。
UML defines a use case as "A description of a set of sequences of actions, including variants, that a system performs that yields an observable result of value to a particular actor.
UML 将一个用例定义为“一个系统执行的一系列行为的描述，包括变量，它将生成特殊参与者所得值的可观测结果。”
A use case focuses on what the stakeholder needs the system to deliver, rather than describing how to arrive at that end result.
用例主要强调涉众需要这个系统交付什么，而不是描述如何实现最终的结果。
应用推荐