Use cases - autonomous behavior

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Use cases - autonomous behavior

Postby atmur » Tue Oct 26, 2004 8:29 pm


I'm working on a system that must monitor a set of temperature sensors, and then control heaters in order to keep the temperatures in a certain range. So, I think I have a use case called MaintainTemperatures. But what is the actor in this situation? The temperature sensors? And what about the heaters - they are acted upon by the system in this use case, so it seems wrong to consider them actors.

Thanks for any ideas.

Alex Murary
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Re: Use cases - autonomous behavior

Postby [gw] Jesco von Voss » Wed Oct 27, 2004 9:33 am

The one who is doing the acting would be your software system. So you can create an actor and stereotype it <<machine>>, to designate that there is some chip that runs your SW system. One could argue that the sensors and heaters are also involved in that use case, so one could also act them as actors, and then specify the exact interaction between all actors in an activity diagram.

The term actor can be applied in a broader sense, to represent all entities that are involved in a specific action sequence (a use case), but I'd say it would also make sense to move to a class diagram at that point and model sensors and heaters as elements that participate in a collaboration. It depends on the level of detail that you want to show.

Jesco von Voss
[gw] Jesco von Voss
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