EA Help file on Choices / Junctions

[mikewhit]

Having been quizzed by a colleague on when to use a Choice and when to use a Junction in a State diagram, I did some reading around.

The EA Help file is not very illuminating on this, just referring to dynamic (C) or static (J) guard conditions.

However, Douglass (Real Time UML, pub Addison Wesley) says that a Choice point is a kind of junction that executes its action list before going on to the next transition segment.

This is presumably from 'classical' state machine terminology, where states are linked by transitions that have events(triggers), guards and actions.

When a trigger occurs, the actions on the transition on which the guard is TRUE are executed.

Douglass goes on to dissuade us from using Choices, on the grounds that you might execute your actions and then find out your guards were all FALSE.

Still, it would be "helpful" if the EA Help file could be a little more forthcoming on this otherwise confusing detail !

[CJ]

Have you tried Zicom Mentor?

[mikewhit]

No, but I was just noting an area where the EA offering could be improved in a minor way, as well as communicating an (IMHO) useful distinction.

Presumably you, CJ, didn't get where you are today without using Zicom Mentor ;-)

(See http://www.mgnet.karoo.net/cjphrases.htm)

[CJ]

G'day,

Fair, for sure.

Yeah, I rely pretty heavily on books and the Mentor for UML and process guidelines.

Although I don't use EA's docs for any kind of UML and/or process documentation, I wouldn't complain if there were more.  Unless, of course, it meant slowing down delivery of functionality goodies.

[Paolo F Cantoni]

Presumably you, CJ, didn't get where you are today without using Zicom Mentor ;-)

(See http://www.mgnet.karoo.net/cjphrases.htm)

Where are you Reginald Perrin, when we need you?

Paolo

[mikewhit]

I think my quote was lost on the Sparx "CJ" - if I was wrong, well, super :-)