USE OF SOFTWARE COMPLEXITY METRICS IN SOFTWARE MAINTENANCE.

A limited subjective study is reported that relates seven different software complexity metrics to the experience of maintenance activities performed on a medium-size software system. Three different versions of the system that evolved over a period of three years were analyzed. A major revision of the system, while still in its design phase, was also analyzed. The results indicate: 1) that the growth in system complexity as determined by the software metrics agree with the general character of the maintenance tasks performed in successive versions; 2) the metrics were able to identify the improper integration of functional enhancements made to the system; 3) the complexity values of the system components as indicated by the metrics conform well to an understanding of the system by people familiar with the system. An analysis of the redesigned version of the system showed the usefulness of software metrics in the redesign phase.