State transition to the border of the state

[ocroquette]

Is the following state diagram done with EA 6.5 UML compliant?
If yes, what's the semantic of the last transition!?



Thanks for your help!

[jeshaw2]

IMO it is not compliant and could be confusing to a reader.

At the point where the transition out of State 5 reaches the border of state 1, you should define an Exit point (The little circle node with an "X" in it).  Once you have done that, the semantic is that when state 5 is exited, State 1 is also exited, but the new state is undefined.

If the new state is defined, then the transition out of state 5 should be connected to the new state and no exit point needs to be defined.

[Paolo F Cantoni]

IMO it is not compliant and could be confusing to a reader.

Dang, Jim, you beat me to it...  I was going to say the semantics were:  "I'm too lazy to to draw the Exit state" or "I didn't actually read the UML standard; but this sure is pretty!"

Examples should be exemplars!

Paolo

[jeshaw2]

Dang, Jim, you beat me to it...

 With you, I've learned to read fast, think deeply, stay up late at night, and type like an engine's cam shaft.  

[jeshaw2]

Speaking of thinking deeply, we are making an assumption of what other intended semantics of the questionable transition  might be:

• If exiting state 5 is only a termination of state 5 but a continuation of state 1, the transition out of state 5 should have a termination node fully within the boundary of state 1;
• If exiting state 5 should cause a re-initialization of state 1, then the transition line should leave the outer state entirely and then return to the state 1's border, ending in an arrowhead.

All these possibilities are why I say the initial diagram is confusing.  UML diagrams must not be ambiguous.

[«Midnight»]

Of course if the business domain is Penology, then the original diagram might be just fine.  

[ocroquette]

Thanks for your comments, they definitely helped.

It seems now to me that the diagram is UML correct, and means that when the sub-state State5 is exited, State1 is entered again from scratch.

Of course it is confusing, and EA custom lines should be used there:



The semantic should be the same as with the first diagram.

[jeshaw2]

It also means, as currently diagrammed, that State 3 is also entered from scratch.

[jeshaw2]

I like Bezier curves for this situation.