Early Evaluation of Implementation Alternatives of Composite Data Structures Toward Maintainability

Selecting between different design options is a crucial decision for object-oriented software developers that affects code quality characteristics. Conventionally developers use their experience to make such decisions, which leads to suboptimal results regarding code quality. In this article, a formal model for providing early estimates of quality metrics of object-oriented software implementation alternatives is proposed. The model supports software developers in making fast decisions in a systematic way early during the design phase to achieve improved code characteristics. The approach employs a comparison model related to the application of the Visitor design pattern and inheritance-based implementation on structures following the Composite design pattern. The model captures maintainability as a metric of software quality and provides precise assessments of the quality of each implementation alternative. Furthermore, the model introduces the structural maintenance cost metric based on which the progressive analysis of the maintenance process is introduced. The proposed approach has been applied to several test cases for different relevant quality metrics. The results prove that the proposed model delivers accurate estimations. Thus, the proposed methodology can be used for comparing different implementation alternatives against various measures and quality factors before code development, leading to reduced effort and cost for software maintenance.