A cohesion measure for object-oriented classes

Abstract

In object-oriented systems, cohesion refers to the degree of the relatedness of the members in a class and strong cohesion has been recognized as a highly desirable property of classes. We note that the existing cohesion measures do not take i n to account s o m e c haracteristics of classes, and thus often fail to properly re ect the cohesiveness of classes. To c o p e w i t h such a problem, we propose a new cohesion measure where the characteristics of classes are incorporated. Our cohesion measure takes into account t h e m e m bers that have actually impact on the cohesiveness of a class, and is de ned in terms of the degree of the connectivity among those members.We develop a cohesion measurement tool for C++ programs and perform a case study on a w ell-known class library in order to demonstrate the e ectiveness of our new measure. By performing principal component analysis, we also demonstrate that our measure captures a new aspect of class properties which is not captured by the existing cohesion measures.

A Survey of Dynamic Software Metrics

“…Despite extensive research work conducted in the measurement of static cohesion [4,[17][18][19][20][21][22][23][24][25][26][27] , only a few metrics have been proposed for the measurement of cohesion at runtime.…”

“…Other major metrics suites proposed for object-oriented systems are MOOD metrics [5] , Lorenz and Kidd metrics [6] , Briand et al metrics [7] , Harrison et al metrics [8] and Bansiya et al metrics [9] . Static metrics focus on static properties of the software and a number of static metrics have been proposed in literature for the measurement of coupling [4,7,[10][11][12][13][14][15][16] , cohesion [4,[11][12][17][18][19][20][21][22][23][24][25][26][27] and other attributes of object-oriented software using design or source code of the software, which are static in nature. The static metrics are able to quantify various aspects of the complexity of design or source code of a software system, but their ability to accurately predict the dynamic behaviour of an application is as yet unproven.…”

Comments on ‘A cohesion measure for object‐oriented classes’ by Heung Seok Chae, Yong Rae Kwon and Doo Hwan Bae (Softw. Pract. Exper. 2000; 30:1405–1431)

“…constructor, destructor, access methods, delegation methods) and normal methods [1,2]. Chae believes that the former kind is designed to show a specific behavior and inherently unrelated to the real cohesion of a class.…”

Cohesion Metrics for Ontology Design and Application

“…More particularly, in object-oriented software, cohesion refers to the degree of the relatedness or consistency in functionality of the members in a class; strong cohesion is recognized as a desirable property of object-oriented classes because it measures separation of responsibilities, independence of components and control of complexity [7,8]. Several software cohesion metrics have been proposed , [9][10][11].…”