Search-Based Requirements Traceability Recovery: A Multi-Objective Approach

Software systems nowadays are complex and difficult to maintain due to the necessity of continuous change and adaptation. One of the challenges in software maintenance is keeping requirements traceability up to date automatically. The process of generating requirements traceability is time-consuming and error-prone. Currently, most available tools do not support the automated recovery of traceability links. In some situations, companies accumulate the history of changes from past maintenance experiences. In this paper, we consider requirements traceability recovery as a multi objective search problem in which we seek to assign each requirement to one or many software elements (code elements, API documentation, and comments) by taking into account the recency of change, the frequency of change, and the semantic similarity between the description of the requirement and the software element. We use the Non-dominated Sorting Genetic Algorithm (NSGA-II) to find the best compromise between these three objectives. We report the results of our experiments on three open source projects.