Change Impact Analysis for UML Model Maintenance

Software maintenance is generally considered to be the most costly phase in the software life-cycle. The software system to be maintained consists of numerous inter-dependent artifacts that inevitably undergo various changes during maintenance. What makes planning and executing these changes difficult is that each change may have severe ``ripple effects'' to other points of the system that are difficult to assess due to the inter-dependent nature of the artifacts. The goal of this chapter is to introduce a lightweight and accurate change impact analysis technique for UML models. Impact analysis rules are created that trace different relationships between UML model elements depending on the type of change applied. We will show that we can achieve good accuracy. To validate the technique, a change scenario that consists of changes that occur during the resolution of inconsistencies between different UML models (correc- tive maintenance) was chosen. The validation is performed on two case studies, which together contain approximately 5686 UML model element instances on which 3287 inconsistencies are resolved. The validation of the two case studies returns a mean precision and recall of (0.77, 0.95) and (0.97, 0.93).