我们可以在一张活动图上画一个用例和用例的所有扩展

　　今天，向umlchina讨论组和argouml用户讨论组发了一封信，请教是否可以在一张活动图上画一个用例和用例的所有扩展。很高兴收到了argouml开发者mvw的回复。他的意见是可以这样做，并且详细解释了用例图中“包括”和“扩展”的关系。从中可以看出argouml开发社区对用户的真诚和友好。这愈发坚定了我使用argouml进行设计的决心。

　　附我的信件和mvw的回信：

From: "Michiel van der Wulp" <mvw@tigris.org>  Add to Address Book  Add Mobile Alert 

To: users@argouml.tigris.org

Date: Tue, 27 Dec 2005 09:28:35 +0100

Subject:  Re: [argouml-users] A question about drawing activity diagram for extends usecases

   

Hi Dashing,

 

Nice colourful diagrams!

 

>> Can I draw the activty diagrams of a usecase and

>> all its extends usecase in one activity diagram?

 

Yes. Since the extends are steps that only happen conditionally, it would be nice to show the condition in the diagram, too. You already did this in the other activity diagram in two ways: with a Junction state (the diamond), and with a Guard - I think both are OK. The junction slightly preferred if people that only know flow-charts have to read the diagrams.

 

One other remark on usecases, which seem to be confused by many, is the difference between include and extend.

An include is comparable with a subroutine: it is always executed, and (usually) only pulled out from the main usecase because it is common with other usecases. An extension is something that happens on a condition somewhere along the path.

 

Regards,

Michiel

 

----- Original Message -----

From: Dashing Meng

To: umlchina@yahoogroups.com ; users@argouml.tigris.org ; 炜 张

Sent: Tuesday, December 27, 2005 4:40 AM

Subject: [argouml-users] A question about drawing activity diagram for extends usecases

Hi,

  Can I draw the activty diagrams of a usecase and all its extends usecase in one activity diagram?here is my usecase diagram:

http://www.learndiary.com/pictures/easyDiary/easyDiaryUseCaseDiagram.gif

this is my activty diagram:

http://www.learndiary.com/pictures/easyDiary/PostADiaryactivityDiagram.gif

my unfinished ArgoUML0.18.1 model:

http://www.learndiary.com/pictures/easyDiary/easyDiary.zargo

 

thanks a lot.