Coherency of Classes to Measure the Quality of Object Oriented Design an Empirical Analysis

Software engineering is an expensive venture to undertake mainly due to not knowing exactly where to focus the reengineering efforts. This is where coupling and cohesion play an important role. Both the metrics, especially cohesion metric, are a potential identification tools that can also measure progress. The current cohesion metrics for classes overlook the characteristics of indirect usage of the instance variables that are so often applicable in a class. Therefore, they are not an ideal reflection of the cohesiveness of the class. Nevertheless, when the variability factor is taking into consideration, the class cohesion factor has not been quantitatively studied. In this paper, we will propose the updated cohesion metrics based on the role of indirect usage of the instance variables. This updated version of cohesion and coupling relation can be used as an indicator to measure changeability. In this paper, we present an approach for remodeling the cohesion metrics by analyzing the characteristics of the indirect instance variable usage in an objectoriented program that can be used as a quality indicator in terms of changeability.