Perfective and corrective UML pattern -based design maintenance with design constraints for information systems.

摘要

Pattern-based design, the use of design pattern during the design process, has become widely used in the object-oriented community because of the reuse benefits that take less cost and effort, but result in high quality in software development and maintenance. However, design pattern defects can be injected in early design without mandatory control of the evolution of a pattern-based design and assessment of pattern-based designs after changes. It is crucial to maintain correct designs during early design maintenance because defects in early design may cause serious damage to software systems in later software development and maintenance.;Hence, there is a need of a systematic design method for preventing design pattern defects being injected during pattern-based design maintenance so that the change results of pattern-based designs conform to the corresponding design patterns. Conventional Unified Modeling Language (UML) 2.0 design methods do not provide systematic ways of assessing pattern-based design conformance.;Pattern Instance Changes with UML Profiles (PICUP) design method is developed as an improved design method for perfective and corrective UML pattern-based design maintenance and assessment. Design pattern in UML Profiles (DPUP) is developed for formal specification of a design pattern. DPUPs are used for instantiation, maintenance, and assessment of UML pattern-based designs. DPUPs, as the main part of PICUP design method, provide metamodel-level UML design constraints using UML stereotype notations and metamodel-level Object Constraint Language (OCL) design constraints.;In this research, assessments of pattern-based designs in UML class diagram with the corresponding DPUPs enforce maintainers to make correct changes of the designs. Pattern-related information is annotated in pattern-based design using stereotype notations. Furthermore, the conformance checking of a given UML pattern-based design can be automated by using the assessment tool.;An explanatory two-case study is used to evaluate the effectiveness of PICUP design method with DPUPs, and applied to (1) the Lexi document editor and (2) the ARENA game information system. Questionnaire answers and design pattern defect counts from the two-case study conducted by subject matter experts support the hypothesis that the PICUP method is an improved design method ensuring structural conformance of UML pattern-based designs to the corresponding design patterns during perfective and corrective design maintenance for information systems.