A Class Cohesion Metric Focusing on Cohesive-Part Size

SUMMARY Cohesion is an important software attribute, and it is one of significant criteria for assessing object-oriented software quality. Although several metrics for measuring cohesion have been proposed, there is an aspect which has not been supported by those existing metrics, that is “cohesive-part size.” This paper proposes a new metric focusing on “cohesive-part size,” and evaluates it in both of qualitative and quantitative ways, with a mathematical framework and an experiment measuring some Java classes, respectively. Through those evaluations, the proposed metric is showed to be a reasonable metric, and not redundant one. It can collaborate with other existing metrics in measuring class cohesion, and will contribute to more accurate measurement.