Interoperability Analysis
XMI round-tripping does not guarantee the preservation of Association Class identity and ownership semantics across the UML 2.4 to 2.5 boundary. While the structural definition of an Association Class—a classifier that is both an Association and a Class—remains stable, the transition involves refinements in metamodel ownership and terminology that are often implemented inconsistently across vendor tools.
Metamodel and Profile Conformance
To remain conformant after the ownership clarification, a profile must be declared against the UML 2.5 metamodel. Profiles defined against UML 2.4 may reference properties or metaclass hierarchies that were redefined or clarified in 2.5. Because profiles are strictly typed against a specific version of the UML metamodel, a version mismatch can lead to the failure of profile application or the loss of stereotyped properties during model transformation.
Compatibility Signaling
Tooling should signal compatibility through semantic validation warnings during the XMI import process. Specifically, tools should:
- Flag Association Classes where the ownership link (e.g., the relationship between the Association and the Classifier role) differs from the source version's declaration.
- Provide a mapping report indicating if an Association Class was downgraded to a standard Class with synthetic associations to maintain structural integrity.
- Alert the user if the XMI namespace declares a version (e.g., 2.4) that conflicts with the target environment's internal metamodel (e.g., 2.5).
Implementation Guidance
To minimize data loss during interchange, follow these steps:
- Export to XMI 2.1: Use the most recent XMI standard supported by both tools to ensure basic structural elements are captured.
- Verify Ownership: After import, manually verify that the Association Class is owned by the correct Package and that the link between the class and the association remains intact.
- Update Profile Declarations: Re-base any custom profiles from UML 2.4 to 2.5 before importing them into a 2.5-conformant environment.
Assumptions and Uncertainty
This analysis assumes the use of standard OMG XMI implementations. However, because many vendors use proprietary XMI extensions or treat Association Classes as simplified classes with foreign keys, actual behavior may vary. Verification is required for specific tool pairs to confirm if ownership metadata is preserved or discarded.
Diagnostic Detail Needed: Are the models being exchanged using a vendor-neutral XMI profile or a tool-specific XMI dialect?
unifiedmodelinglanguage