[ 
http://issues.apache.org/jira/browse/SCXML-27?page=comments#action_12439571 ] 
            
Rahul Akolkar commented on SCXML-27:
------------------------------------

Let me state my assertions behind resolving this as won't fix:

a) The class in question has non-trivial functionality
b) We tried to make it pluggable, exactly for these kind of usecases
c) Custom semantics is considered advanced API for the library
d) The existing method signatures and call stack cannot be compromised
e) Because of (a) and (d), some (or many) cases might require subclasses to 
indulge in copious copy-paste to find the correct insertion points
f) I personally expect advanced users to be somewhat more tolerant than casual 
users
g) Making a particular change that makes sense for any one usecase does not 
solve this issue eternally

To reopen this ticket, therefore, we need a complete proposal stating how:

a) Subclassing convenience has improved for many (if not all) usecases 
(preferred way to illustrate is test cases)
b) All existing API contracts are preserved
c) The changes (additions, really) constitute the minimal essential set

This is not to say your suggestion may not have merit for your usecase, it 
does, but these are the (more important) broader constraints.

> Improve possibility to extending (subclassing) the default semantics
> --------------------------------------------------------------------
>
>                 Key: SCXML-27
>                 URL: http://issues.apache.org/jira/browse/SCXML-27
>             Project: Commons SCXML
>          Issue Type: Improvement
>    Affects Versions: 0.5
>            Reporter: Hallvard Trætteberg
>
> I've extended the default SCXML semantics (subclassed SCXMLSemanticsImpl) 
> with a more flexible event matching method. However, this required copying a 
> lot of code from SCXMLSemanticsImpl, just to replace the event matching 
> method. The problem was that the eventMatch method takes String and Set 
> arguments, with no way to get at the Transition who's event is to be tested. 
> I copied the relevant code and replaced eventMatch(String,Set) with 
> eventMatch(Transition,Set), to make it more flexible. I ask that this change 
> is made to SCXMLSemanticsImpl, to better support overriding.
> The flexibility I've added is to use regular expressions for matching, and 
> since this happens often, I wanted to cache the compiled pattern. The natural 
> place to do this is the Transition, so I subclassed the Transition class, 
> included a field for holding the compiled pattern and made sure to use this 
> subclass whenever a regexp was needed. Then in the modified eventMatch code, 
> I check whether the Transition is of this subclass and used the cache to 
> improve performance.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: 
http://issues.apache.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira



---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

Reply via email to