Change impact analysis and changeability assessment for a change proposal: An empirical study

Software change is a fundamental ingredient of software maintenance and evolution. Effectively supporting software modification is essential to provide a reliable high-quality evolution of software systems, as even a slight change may cause some unpredictable and undesirable effects on other parts of the software. To address this issue, this work used change impact analysis (CIA) to guide software modification. CIA can be used to help make correct decision on the change proposal, that is changeability assessment, and to implement effective changes for a change proposal. In this article, we conducted an empirical study on three Java open-source systems to show how CIA can be used during software modification. The results indicate that: (1) assessing changeability of a change proposal based on the impact results of the CIA is not accurate from the precision perspective; (2) the proposed impactness metric is an effective indicator of changeability assessment for the change proposal; and (3) CIA can make the change implementation process more efficient and easier.