Documenting Typical Crosscutting Concerns

Our analysis of crosscutting concerns in real-life software systems (totaling over 500,000 LOC) and in reports from literature indicated a number of properties that allow for their decomposition in primitive building blocks which are atomic crosscutting concerns. We classify these blocks in crosscutting concern sorts, and we use them to describe the cross- cutting structure of many (well-known) designs and common mechanisms in software systems. In this paper, we formalize the notion of crosscutting concern sorts by means of relational queries over (object-oriented) source models. Based on these queries, we present a concern management tool called SoQUET, which can be used to document the occurrences of crosscutting concerns in object-oriented systems. We assess the sorts-based approach by using the tool to cover various crosscutting concerns in two open-source systems: JHOTDRAW and Java PETSTORE.