Inter-association Constraints in UML2: Comparative Analysis, Usage Recommendations, and Modeling Guidelines

摘要

UML specification is verbal and imprecise, the exact meaning of many class diagram constructs and their interaction is still obscure. There are major problems with the inter-association constraints subsets, union, redefinition, association specialization, association-class specialization. Although their standard semantics is ambiguous and their interaction unclear, the UML meta-model intensively uses these constraints. The paper investigates the semantic implications of the above inter-association constraints, their interaction with other constraints, and implied correctness problems. Based on this study, we present a comparative analysis of these constraints, that includes characterization, and refers to complexity factors, and usefulness aspect. This analysis yields recommendations concerning the semantics and usefulness of the constraints. In addition, we present modeling guidelines for users. To the best of our knowledge, this is the first all inclusive analysis of the inter-association constraints in UML2.