Software Cinema

前一陣子計畫工作需要, 對不同的 use cases 寫法作了 survey.

A. Cockburn 著名的 Writing Effective Use Cases [Cockburn01] 其實已經歸納了好一部分, 然而牽涉到 user interface design 相關的部分時, 有些 use case 的寫法也不在他的歸納內.

底下就我 survey 的, 自行整理數個類別, 請注意下面的許多 diagram 名稱在 UML 中也出現, 但內涵並不完全相同.

• Scenario Style (Continuous Narrative Style) [Constantine01]
• Numbered Sentences [Constantine01]
• Mainstream Use Case Writing Style [Cockburn01][Overgaard04][Rosenberg01][Rosenberg07]
• Partitioned Narratives [Constantine01]
• Essential Use Cases [Constantine01]
• Activity Diagram [Almendros-Jim´enez05]
• Collaboration Diagram [Elkoutbi99]
• Use Case Maps [UCM07]
  
• Sequence Chart [Cockburn01]
  

Mainstream Use Case Writing Style 指的是目前主流的寫法, 具有 use case name, actor, use case relationships, pre-conditions, post-conditions, flow of events, alternative flow of events 等等. 其他的在相關的 references 裡都有清楚說明了, 在此不贅述.

比較有意思的是在 [Constantine01] 中使用的 Partitioned Narratives style, 為了方便 user interface design, 建議把 flow of events 分為 actor 以及 system 兩邊分開論述, 這樣彼此的 action/reaction 就會比較清楚. 在目前主流的寫法中尚未有此慣例, 但是似乎也有人開始建議應該在主流的寫法中加上此 style 限制, 讓 use case 轉換成為 object & associations 的過程中, 可以更順利, 減少不必要的 iterations.

另外 Use Case Map [UCM07] 是我一直很感興趣的項目. 第一次接觸 Use Case Map 大約是兩年前的事情了, 但是直到現在相關的 research papers 還是差不多兩年前的量, 頂級的研究成果更是缺乏, 但我始終覺得 UCM 很有潛力說, 可能只是時候未到吧, 還沒有遇到適合的 application context.


References

[Cockburn01] Alistair Cockburn, "Writing Effective Use Cases," Addison-Wesley, 2001
[Overgaard04] Gunnar Overgaard, Karin Palmkvist, "Use Cases: Patterns and Blueprints," Addison-Wesley, 2004
[Rosenberg01] Doug Rosenberg, Kendall Scott, "Applying Use Case Driven Object Modeling with UML: An Annotated e-Commerce Example," Addison-Wesley, 2001
[Rosenberg07] Doug Rosenberg, Matt Stephens, "Use Case Driven Object Modeling with UML: Theory and Practice," Apress, 2007
[Constantine01] Larry L. Constantine, Lucy A. D. Lockwood, Structure and Style in Use Cases for User Interface Design, URL : http://www.foruse.com/Files/Papers/structurestyle2.pdf
[Almendros-Jim´enez05] Jes´us M. Almendros-Jim´enez and Luis Iribarne, "Designing GUI components from UML Use Cases," Proceedings of the 12th IEEE International Conference and Workshops on the Engineering of Computer-Based Systems (ECBS’05), 2005.
[Elkoutbi99] M. Elkoutbi, I. Khriss, and R. K. Keller, "Generating User interface Prototypes from Scenarios", PRocs of RE'99, 1999.
[UCM07] Use Case Maps, URL : http://www.usecasemaps.org/