Issue 16292: Use cases specifying the same subject cannot be associated: exception (uml2-rtf) Source: (, ) Nature: Enhancement Severity: Significant Summary: The UML Superstructure Specification V2.4 states in 16.3.6 UseCase (from UseCases): “Two use cases specifying the same subject cannot be associated since each of them individually describes a complete usage of the subject.” For the longest time, this looked like a common-sense rule. However, it seems to me that in the context of SOA there is at least on exception to this rule. Let’s say that: 1. The subject represents a component (as understood in SOA) and the use cases represent the component’s services. 2. The initiating actor of all of the component’s services is Another Use Case. This reflects the SOA reality that services are not directly consumed by human actors but by other use cases. 3. The component offers services A and B, both of which trace back to legitimate uses. 4. As it happens, when service B is defined in detail it turns out that one of its steps amounts exactly to the functionality represented as service A. In such situations, where the subject already has a public service (A) that can actually be reused by one or more of its other public services (B), I think it’s entirely reasonable to allow B to be associated with A. After all, A’s initiating actor is Another Use Case, which is exactly what B is. In object-orientated terms this amounts to an object performing an operation on itself. I propose for UML to accommodate this scenario. Resolution: Revised Text: Actions taken: May 28, 2011: received issue Discussion: End of Annotations:===== iler: QUALCOMM Windows Eudora Version 7.1.0.9 Date: Wed, 01 Jun 2011 16:05:22 -0400 To: issues@omg.org, uml2-rtf@omg.org From: Juergen Boldt Subject: issue 16292 -- UML 2 RTF issue From: webmaster@omg.org Date: 28 May 2011 21:34:01 -0400 To: Subject: Issue/Bug Report ******************************************************************************* Name: Willem Van Galen Employer: London Life Insurance Co. mailFrom: willem.vangalen@londonlife.com Terms_Agreement: I agree Specification: OMG Unified Modeling Language (OMG UML), Superstructure Section: 16.3.6 UseCase (from UseCases) FormalNumber: ptc/2010-11-14 Version: 2.4 Doc_Year: 2011 Doc_Month: January Doc_Day: 01 Page: 613 Title: Use cases specifying the same subject cannot be associated: exception Nature: Enhancement Severity: Significant CODE: 3TMw8 B1: Report Issue Description: The UML Superstructure Specification V2.4 states in 16.3.6 UseCase (from UseCases): .Two use cases specifying the same subject cannot be associated since each of them individually describes a complete usage of the subject.. For the longest time, this looked like a common-sense rule. However, it seems to me that in the context of SOA there is at least on exception to this rule. Let.s say that: 1. The subject represents a component (as understood in SOA) and the use cases represent the component.s services. 2. The initiating actor of all of the component.s services is Another Use Case. This reflects the SOA reality that services are not directly consumed by human actors but by other use cases. 3. The component offers services A and B, both of which trace back to legitimate uses. 4. As it happens, when service B is defined in detail it turns out that one of its steps amounts exactly to the functionality represented as service A. In such situations, where the subject already has a public service (A) that can actually be reused by one or more of its other public services (B), I think it.s entirely reasonable to allow B to be associated with A. After all, A.s initiating actor is Another Use Case, which is exactly what B is. In object-orientated terms this amounts to an object performing an operation on itself. I propose for UML to accommodate this scenario. Kind regards, Willem Van Galen Senior Systems Analyst London Life Insurance Co. 255 Dufferin Ave. London, ON N6A 4K1 CANADA Juergen Boldt Director, Member Services 140 Kendrick Street, Building A Suite 300 Needham, MA 02494 USA Tel: 781 444 0404 x 132 fax: 781 444 0320 www.omg.org