Assessing and restructuring of classes based on cohesion

Abstract

Classes are the fundamental concepts in the object-oriented paradigm. They are the basic units of object-oriented programs, and serve as the units of encapsulation, which promotes their modifiability and reusability. However, improper modeling in the design phase or uncontrolled changes during the maintenance phase can degrade the quality of classes, which leads to programs which are cumbersome to maintain or extend. The paper proposes a method for assessing the quality of classes and restructuring them. The authors define an abstraction as the most cohesive form of a class, and the cohesion indicates the extent to which a class approaches the abstraction. Assessment and restructuring are both based on the notion of class cohesion. Less cohesive classes can be transformed into a form of an abstraction by restructuring them.