Issue 6497: ptc-03-09-15/Need for examples to include instance models (uml2-rtf) Source: David Frankel Consulting (Mr. David Frankel, david(at)dfrankelconsulting.com) Nature: Uncategorized Issue Severity: Summary: Issue and Recommendation: In general the specification of the Core would benefit from instance diagrams accompanying example models, especially in cases where there is significant change from UML 1.x. An instance diagram accompanying an example model would show how the model instantiates the elements of metamodel. This will contribute to a greater level of common understanding among readers of the specification and thus will help ensure interoperability. For example, consider Figure 3-23 from the submission document and which defines the abstract syntax for the elements of the Core::Constructs::Constraints package. Despite the existence of accompanying explanatory text, the distinction between the Namespace that owns a Constraint and the Namespace that provides the context for a Constraint may be difficult for the reader to grasp completely. Figures 3-24, 3-25, and 3-26 from the submission document, respectively, provide example models. An instance diagram for at least one of the examples that shows how the elements of the example model instantiate elements of Core::Constructs::Constraints would go a long way toward preventing misunderstandings. Such misunderstandings would compromise interoperability, since there is a high probability (in my opinion) that different implementers would render models to XMI differently. This example is only one of many that I could cite from the submission where examples *plus* associated instance diagrams would be beneficial. Resolution: Revised Text: Actions taken: November 7, 2003: received issue February 18, 2005: moved from infrastructure Discussion: Disposition: Deferred to UML 2.4 RTF End of Annotations:===== m: "David S. Frankel" To: Subject: UML2Infra-MOF2Core/ ptc-03-09-15/Need for examples to include instance models Date: Fri, 7 Nov 2003 22:03:52 -0800 X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal Issue and Recommendation: In general the specification of the Core would benefit from instance diagrams accompanying example models, especially in cases where there is significant change from UML 1.x. An instance diagram accompanying an example model would show how the model instantiates the elements of metamodel. This will contribute to a greater level of common understanding among readers of the specification and thus will help ensure interoperability. For example, consider Figure 3-23 from the submission document and which defines the abstract syntax for the elements of the Core::Constructs::Constraints package. Despite the existence of accompanying explanatory text, the distinction between the Namespace that owns a Constraint and the Namespace that provides the context for a Constraint may be difficult for the reader to grasp completely. Figures 3-24, 3-25, and 3-26 from the submission document, respectively, provide example models. An instance diagram for at least one of the examples that shows how the elements of the example model instantiate elements of Core::Constructs::Constraints would go a long way toward preventing misunderstandings. Such misunderstandings would compromise interoperability, since there is a high probability (in my opinion) that different implementers would render models to XMI differently. This example is only one of many that I could cite from the submission where examples *plus* associated instance diagrams would be beneficial. ================================================================= David S. Frankel David Frankel Consulting Email: df@DavidFrankelConsulting.com Web: www.DavidFrankelConsulting.com Tel: +1 530 893-1100 Fax: +1 530 893-1153 David Frankel's MDA book: www.DavidFrankelConsulting.com/book.htm =================================================================