Cell Phone Software Forum
| View previous topic :: View next topic |
| Author |
Message |
Cyclone
Guest
|
 Posted: Fri May 04, 2007 2:54 am Post subject: Question on Use Cases |
 |
|
Folks :
I am working on defining use cases for my system.
a) There are specific actors for the application who shall be
reveiwing information, entering information etc. I have identified
them already.
b) However, I also have cases where the system itself shall be
initiating events (like timed events or in response to an external
stimulus) to process data and send it across to another actor.
Hence, I am curious if the Use Case diagram that I am working on can/
should contain my system itself as an actor. This will allow me to
depict action on the use cases I am trying to depict for b) above.
Otherwise, I am not sure if I can have a standalone usecase defined
that may not be acted upon but shall send information to another
actor.
Please advice what is the right approach here.
Thanks in advance,
Cyclone. |
|
| Back to top |
|
 |
| |
Ads |
Advertising
Sponsor
|
|
Ernie Englehart
Guest
|
| Posted: Fri May 04, 2007 3:41 am Post subject: Re: Question on Use Cases |
|
|
Yes, the system can be an actor in a use case.
"Cyclone" <pawan.g@gmail.com> wrote in message news:1178232880.373599.37090@p77g2000hsh.googlegroups.com...
| Quote: |
Folks :
I am working on defining use cases for my system.
a) There are specific actors for the application who shall be
reveiwing information, entering information etc. I have identified
them already.
b) However, I also have cases where the system itself shall be
initiating events (like timed events or in response to an external
stimulus) to process data and send it across to another actor.
Hence, I am curious if the Use Case diagram that I am working on can/
should contain my system itself as an actor. This will allow me to
depict action on the use cases I am trying to depict for b) above.
Otherwise, I am not sure if I can have a standalone usecase defined
that may not be acted upon but shall send information to another
actor.
Please advice what is the right approach here.
Thanks in advance,
Cyclone.
|
|
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
Michael
Guest
|
| Posted: Fri May 04, 2007 3:52 am Post subject: Re: Question on Use Cases |
|
|
On May 3, 4:41 pm, "Ernie Englehart" <eengleh...@gmail.com> wrote:
| Quote: |
Yes, the system can be an actor in a use case.
|
Instead of drawing it as a stick figure with a round head, it is
frequently drawn as a stick figure with a square head (as if the head
is a computer monitor) to indicate that this is not a human actor, but
rather an automated actor. The same kind of stick figure would be
used, for example, if some external system interacted with your
system.
Michael |
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
Gabriel Claramunt
Guest
|
| Posted: Fri May 04, 2007 5:16 am Post subject: Re: Question on Use Cases |
|
|
Your system can never be an actor... other systems can.
The main purpose of finding the actors of your system is to identify
boundaries and which external interfaces you need to provide.
By definition, anything inside your system doesn't need an external
interface. You can have outside events as actors (Time, sensors, etc.) when
they trigger actions in your system.
There's an interesting discussion from "Doctor Use Case" in:
www-128.ibm.com/developerworks/rational/library/content/RationalEdge/jun02/DrUseCaseJun02.pdf
He recommneds asking yourself "Who truly wants the functionality?"
Gabriel Claramunt
http://gabrielsw.blogspot.com/
"Cyclone" <pawan.g@gmail.com> wrote in message
news:1178232880.373599.37090@p77g2000hsh.googlegroups.com...
| Quote: |
Folks :
I am working on defining use cases for my system.
a) There are specific actors for the application who shall be
reveiwing information, entering information etc. I have identified
them already.
b) However, I also have cases where the system itself shall be
initiating events (like timed events or in response to an external
stimulus) to process data and send it across to another actor.
Hence, I am curious if the Use Case diagram that I am working on can/
should contain my system itself as an actor. This will allow me to
depict action on the use cases I am trying to depict for b) above.
Otherwise, I am not sure if I can have a standalone usecase defined
that may not be acted upon but shall send information to another
actor.
Please advice what is the right approach here.
Thanks in advance,
Cyclone.
|
|
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
Gabriel Claramunt
Guest
|
| Posted: Fri May 04, 2007 5:17 am Post subject: Re: Question on Use Cases |
|
|
Only if is not the system you are developing :-)
"Ernie Englehart" <eenglehart@gmail.com> wrote in message
news:N--dnTcs3_6u7qfbnZ2dnUVZ_gidnZ2d@comcast.com...
Yes, the system can be an actor in a use case.
"Cyclone" <pawan.g@gmail.com> wrote in message
news:1178232880.373599.37090@p77g2000hsh.googlegroups.com...
| Quote: |
Folks :
I am working on defining use cases for my system.
a) There are specific actors for the application who shall be
reveiwing information, entering information etc. I have identified
them already.
b) However, I also have cases where the system itself shall be
initiating events (like timed events or in response to an external
stimulus) to process data and send it across to another actor.
Hence, I am curious if the Use Case diagram that I am working on can/
should contain my system itself as an actor. This will allow me to
depict action on the use cases I am trying to depict for b) above.
Otherwise, I am not sure if I can have a standalone usecase defined
that may not be acted upon but shall send information to another
actor.
Please advice what is the right approach here.
Thanks in advance,
Cyclone.
|
|
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
Gabriel Gonzalez
Guest
|
| Posted: Fri May 04, 2007 11:31 am Post subject: Re: Question on Use Cases |
|
|
Maybe this previous discussion helps. But in short, all the actions
must be started by an external actor.
"timed events" should be modeled as an action started by maybe the OS
since it is going to send a signal to your app.
"external stimulus" The component who sends that stimulus is the actor
of the use case.
Cheers,
Gabriel Gonzalez.
On May 4, 12:54 am, Cyclone <pawa...@gmail.com> wrote:
| Quote: |
Folks :
I am working on defining use cases for my system.
a) There are specific actors for the application who shall be
reveiwing information, entering information etc. I have identified
them already.
b) However, I also have cases where the system itself shall be
initiating events (like timed events or in response to an external
stimulus) to process data and send it across to another actor.
Hence, I am curious if the Use Case diagram that I am working on can/
should contain my system itself as an actor. This will allow me to
depict action on the use cases I am trying to depict for b) above.
Otherwise, I am not sure if I can have a standalone usecase defined
that may not be acted upon but shall send information to another
actor.
Please advice what is the right approach here.
Thanks in advance,
Cyclone. |
|
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
H. S. Lahman
Guest
|
| Posted: Fri May 04, 2007 6:58 pm Post subject: Re: Question on Use Cases |
|
|
Responding to Cyclone...
| Quote: |
I am working on defining use cases for my system.
a) There are specific actors for the application who shall be
reveiwing information, entering information etc. I have identified
them already.
b) However, I also have cases where the system itself shall be
initiating events (like timed events or in response to an external
stimulus) to process data and send it across to another actor.
Hence, I am curious if the Use Case diagram that I am working on can/
should contain my system itself as an actor. This will allow me to
depict action on the use cases I am trying to depict for b) above.
Otherwise, I am not sure if I can have a standalone usecase defined
that may not be acted upon but shall send information to another
actor.
|
If depends on where you are writing your use cases. Anything outside
scope of the software to which the use cases apply is external and any
external sources of stimuli are actors. So if your use cases are for a
large, distributed system, then all the elements of the system are of
internal scope while anything outside the system is external. If your
uses cases are written for each distributed component individually, then
anything outside the scope of the component in hand is external.
The lowest boundary for defining external vs. internal is typically the
subsystem. So if you have use cases defined for each subsystem, then any
communication with a subsystem is and external actor, even if it is from
another subsystem that you developed within the same process.
Things like timers are usually provided externally (e.g., OS services)
so they are usually external to the software being constructed and can
be regarded as actors. In addition, any realized code (i.e., code
already developed outside the scope of the software being specified,
such as third party packages and layers) is usually regarded as being
external to the code being developed, so it qualifies as an actor.
*************
There is nothing wrong with me that could
not be cured by a capful of Drano.
H. S. Lahman
hsl@pathfindermda.com
Pathfinder Solutions
http://www.pathfindermda.com
blog: http://pathfinderpeople.blogs.com/hslahman
"Model-Based Translation: The Next Step in Agile Development". Email
info@pathfindermda.com for your copy.
Pathfinder is hiring:
http://www.pathfindermda.com/about_us/careers_pos3.php.
(888)OOA-PATH |
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
223 Attacks blocked
Powered by phpBB © 2001, 2005 phpBB Group
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
