Teaching Classes' Relations: A Walkthrough Using UML Arrow Methodology

Object oriented design involves, among other, selecting entities and relationships between them. Our past practical experience shows that often, students select inappropriate relations between classes regardless of their formal education. This paper presents a UML arrow methodology for supporting classes' relationship selection using UML notation. The methodology is comprised of an orientation checklist, which provides immediate positive or negative feedback to guiding questions, and a governing iterative process. This methodology was practiced in university courses following data analysis acquired from 142 participants. The effectiveness of the methodology was manifested in the identification of inappropriate relationships and of required refactoring actions. Consequently the students design artifacts were gradually improved.