Query-based filtering and graphical view generation for clone analysis

Code clones are similar program structures recurring in software systems. Clone detectors produce much information and a challenge is to identify useful clones depending on the goals of clone analysis. To do so, further abstraction, filtering and visualization of cloning information, with the involvement of a human expert, is required. In this paper, we describe a technique for filtering and visualization of cloning information generated by Clone Miner, a clone detection tool presented in our earlier work. Unique benefit and contribution of our approach is that a human expert can define a wide range of filters to extract abstract views of the cloning data using a clone-query system to suit specific needs of clone analysis. We then produce standardized graphical presentations of those views for various types of clone queries. We implemented the technique into an Eclipse plug-in called Clone Visualizer. Clone Visualizer works closely with Clone Miner which not only finds similar code fragments (simple clones) but also finds higher-level abstractions of the cloning information. Our method is the first attempt to address filtering and visualization of those higher level cloning abstractions. We illustrate application of our technique with examples from a clone analysis project with Clone Miner and Clone Visualizer.