Studying the Effect of Refactorings: A Complexity Metrics Perspective

Refactoring is widely recognized as a way to improve the internal structure of a software system in order to ensure its long-term maintainability. Consequently, software projects which adopt refactoring practices should see reductions in the complexity of their code base. We evaluated this assumption on an open source system —namely PMD, a Java source code analyzer— and discovered that periods of refactorings did not affect the cyclomatic complexity. This paper investigates this counterintuitive phenomenon through a detailed analysis of the actual source code manipulations applied on the system under study.

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