Issue 15849: Creation of an expansion node under an activity is allowed by UML and SysML specifications (uml2-rtf) Source: (, ) Nature: Revision Severity: Significant Summary: Which semantic for an expansion node owned by an activity (instead an expansion region)? According OMG Unified Modeling LanguageTM (OMG UML), Superstructure, Chapter 12.3.26 An expansion node is an object node used to indicate a flow across the boundary of an expansion region. An expansion region is a structured activity region that executes multiple times corresponding to elements of an input collection. This specific structured activity node is using expansion node as input and output. From outside the expansions regions the elements of expansion nodes only appear as a collections, the elements of collection are only accessible from "inside the collection". Semantic of an expansion node owned by an expansion region is then well defined. However, in abstract syntax nothing prevents to create an expansion node owned by an activity instead of an expansion region. In this case semantic is questionable. If this kind of construction is not expected, a specific constraint should be added in UML specification in order to prevent an activity to owned expansion nodes. On the contrary, if this construction allowed, associates semantic should be defined. Resolution: Revised Text: Actions taken: November 29, 2010: received issue Discussion: End of Annotations:===== m: webmaster@omg.org Date: 29 Nov 2010 10:53:45 -0500 To: Subject: Issue/Bug Report ******************************************************************************* Name: gautreault fabien Employer: Safran Engineering Services/Airbus mailFrom: fabien.gautreault.external@safran-engineering.com Terms_Agreement: I agree Specification: OMG Unified Modeling LanguageTM (OMG UML), Superstructure Section: 12.3.26 FormalNumber: formal/2010-05-05 Version: 2.3 Doc_Year: 2010 Doc_Month: May Doc_Day: 05 Page: 377 Title: Creation of an expansion node under an activity is allowed by UML and SysML specifications. Nature: Revision Severity: Significant CODE: 3TMw8 B1: Report Issue Description: Which semantic for an expansion node owned by an activity (instead an expansion region)? According OMG Unified Modeling LanguageTM (OMG UML), Superstructure, Chapter 12.3.26 An expansion node is an object node used to indicate a flow across the boundary of an expansion region. An expansion region is a structured activity region that executes multiple times corresponding to elements of an input collection. This specific structured activity node is using expansion node as input and output. From outside the expansions regions the elements of expansion nodes only appear as a collections, the elements of collection are only accessible from "inside the collection". Semantic of an expansion node owned by an expansion region is then well defined. However, in abstract syntax nothing prevents to create an expansion node owned by an activity instead of an expansion region. In this case semantic is questionable. If this kind of construction is not expected, a specific constraint should be added in UML specification in order to prevent an activity to owned expansion nodes. On the contrary, if this construction allowed, associates semantic should be defined. Subject: RE: issue 15849 -- UML 2 RTF issue Date: Mon, 29 Nov 2010 17:00:47 -0500 X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: issue 15849 -- UML 2 RTF issue Thread-Index: AcuQDuZFZe0imY83TTWoz+/Iti9uzAAANSGg From: "Ed Seidewitz" To: "Juergen Boldt" , , Cc: Actually, an expansion node is never owned by an expansion region, since the associations between ExpansionRegion and ExpansionNode are not ownership associations. This means that expansion nodes must always be owned by an enclosing activity (or structured activity node), not by their expansion node directly. However, Constraint [1] on ExpansionNode states that .One of regionAsInput or regionAsOutput must be non-empty, but not both.. So every expansion node is associated with exactly one expansion region, even if it is not actually owned by that region. The semantics of an expansion node are always relative to the expansion region with which it is associated (as input or as output). Nevertheless, it might be a good idea to have a constraint that an expansion node always has the same owner as its expansion region. I am not quite sure what it would mean to have, e.g., an expansion region nested in a structured activity node while its expansion nodes are still owned by the outer activity, or vice versa, though the given semantics for the region would probably still work. -- Ed -------------------------------------------------------------------------------- From: Juergen Boldt [mailto:juergen@omg.org] Sent: Monday, November 29, 2010 4:44 PM To: issues@omg.org; uml2-rtf@omg.org Subject: issue 15849 -- UML 2 RTF issue From: webmaster@omg.org Date: 29 Nov 2010 10:53:45 -0500 To: Subject: Issue/Bug Report ******************************************************************************* Name: gautreault fabien Employer: Safran Engineering Services/Airbus mailFrom: fabien.gautreault.external@safran-engineering.com Terms_Agreement: I agree Specification: OMG Unified Modeling LanguageTM (OMG UML), Superstructure Section: 12.3.26 FormalNumber: formal/2010-05-05 Version: 2.3 Doc_Year: 2010 Doc_Month: May Doc_Day: 05 Page: 377 Title: Creation of an expansion node under an activity is allowed by UML and SysML specifications. Nature: Revision Severity: Significant CODE: 3TMw8 B1: Report Issue Description: Which semantic for an expansion node owned by an activity (instead an expansion region)? According OMG Unified Modeling LanguageTM (OMG UML), Superstructure, Chapter 12.3.26 An expansion node is an object node used to indicate a flow across the boundary of an expansion region. An expansion region is a structured activity region that executes multiple times corresponding to elements of an input collection. This specific structured activity node is using expansion node as input and output. From outside the expansions regions the elements of expansion nodes only appear as a collections, the elements of collection are only accessible from "inside the collection". Semantic of an expansion node owned by an expansion region is then well defined. However, in abstract syntax nothing prevents to create an expansion node owned by an activity instead of an expansion region. In this case semantic is questionable. If this kind of construction is not expected, a specific constraint should be added in UML specification in order to prevent an activity to owned expansion nodes. On the contrary, if this construction allowed, associates semantic should be defined. Juergen Boldt Director, Member Services Object Management Group 140 Kendrick St Building A Suite 300 Needham, MA 02494 USA tel: +1 781 444 0404 x 132 fax: +1 781 444 0320 email: juergen@omg.org www.omg.org