Cloning practices: Why developers clone and what can be changed

Code clones are similar code segments. Researchers have proposed many techniques to detect, understand and eliminate code clones. However, due to lack of deeper understanding of reasons of cloning practices, especially from personal and organizational perspectives, little effective support can be provided to alleviate maintenance problems caused by code clones. In this paper, we report an industrial study on investigating reasons of cloning practices in large-scale software development from technical, personal, and organizational perspectives. Our study involves code analysis, questionnaire survey, and interviews with developers, and gathers solid empirical data about how developers clone and why during different phases of clones' lifecycle in industrial development. The results of our study suggest that cloning is not simply a technical issue; it must be interpreted and understood in larger context in which code clones occur and evolve. Within these contexts, there are several adjustable factors and two critical points that affect the introduction, existence, and removal of clones. These adjustable factors and critical points reveal opportunities to improve cloning practices in industrial development from technical, personal, and organizational perspectives.