commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Christopher Dragert <>
Subject RE: [scxml-eclipse] User Feedback
Date Mon, 02 Aug 2010 17:17:46 GMT
Hi, thank you for your response.  I have replied inline:

>> I've gone through some of the basic functionality of the plug-in and
>> generally found it to be good.  I have several points of feedback:
>> 1) A small feature request:  Can you display the event name on the diagam
>> like you do for a condition?
> Yes,  we can display event name one the diagram, but i do not want to do it
>like this, too many characters on the diagram will make the canvas more

Harel [1] states that "The general syntax of an expression labelling a transition in a state
chart is “m[c]/a” where m is the message that triggers the transition, c is a condition
that guards the transition from being taken unless it is true when m occurs, and a is an action
that is carried out if and when the transition is taken. All of these parts are optional."

I think that the reduction of clutter is not a strong argument to go against general syntax,
as the graphical representation loses a lot of meaning when "m" is not shown.  If no conditions
are used, then the graphical representation shows only unlabelled transitions, which does
not explain the behaviour of the state-chart.  While Harel says these parts are optional,
it doesn't make a lot of sense to omit information that is meaningful.

That being said, showing "/a" will be hard in scxml, since this refers to a block of executable
content.  Preferrably, the block of executable content would be shown in the format "m[c]/executable
content window", however, this could become very cluttered and perhaps something alternate
could be done to show the link between the transition and its executable content. 

>> 3) There seems to be no way to have executable content on a transition.  Is
>> this under development?
>I do not find any executable content on a transition in W3C's SCXML
>specification recommendtaion, so i am not clear what you mean.

As Jacob mentioned, the SCXML standard allows executable content as children for transitions
(section 3.3.2)

>> 4)  Seems to crash frequently and give out of memory errors, even while
>> using -Xmx1024m.  I have to save and restart every minute or two.
>In my development experience, i have not came across crash situation, so i
>think there may be something wrong in your environment. Or, if it crash when
>you are debug/running source code, you can export plug-in jars, and install
>them in Eclipse environmet, i do not think it will crash more

I am using the eclipse environment that was indicated and followed the instructions to get
the code.  This should mean the environment is identical to yours?  Anyway, I'll produce some
detailed bug reports to give you more information.

Chris Dragert

[1] Harel, D., Kugler, H.: The RHAPSODY Semantics of Statecharts or, On the Executable Core
of the UML). In: Integration of Software Specification Techniques for Application in Engineering,
Lecture Notes in Computer Science, vol. 3147, pp.325–354. Springer, Berlin Heidelberg New
York (2004).
View raw message