New Inheritance Complexity Metrics for Object-Oriented Software Systems: An Evaluation with Weyuker's Properties

Two inheritance complexity metrics, one at class level CCI (Class Complexity due to Inheritance) and another at program level ACT (Average Complexity of a program due to Inheritance), have been proposed for object-oriented software systems. These proposed metrics are evaluated with Weyuker's properties and compared with other well known objectoriented inheritance metrics. It has been found that the proposed metrics better represent the complexity, due to inheritance, of a class and a program. Weyuker's property 7 (Significance of Permutation) has received a negative response regarding its applicability to object-oriented software metrics. It has been observed that this property is not satisfied by any of the objectoriented inheritance metrics proposed so far. Contrary to past beliefs, the relevance of this property to object-oriented systems has been brought out in this paper. Examples with C++ code are also presented to support the applicability of this property.