The measurement and analysis of software change based on software repository

Software changes are inevitable during software evolution. And knowing little about changes is the most significant reason which increased the cost and risk of the changes. The approach of change complexity measurement based on software repositories is proposed in this paper. The atomic change types are defined. The change complexity model and related metric indictors are presented. And the automatic change measuring tool, shorted as CMT, based on the proposed method has been implemented, which can be used to measure the change complexity of java projects. Then the simple way to analyze the frequently changed classes and change couplings is introduced. Finally, the proposed systematic approach has been evaluated on a multi-version medium sized open source project called JEdit, which indicates the simplicity and rationality of our approach.