On the detection of code clones with sequence of method calls

Abstract

Software developers usually copy and paste code from a part of the system to another. This practice, called code clone, spreads same logic all over the system, hardening maintenance and evolution tasks. Several methods were proposed in order to locate code clones for further elimination. However, some types of code clones are hard to find, specially when the parts receive different changes. This work proposes a method for detecting code clones analyzing sequence of method calls. Our results were compared with code clones detected by a state of the practice tool, called PMD. In addition, a user study was conducted in order to manually evaluate the detections. Participants analyzed the code clones detected by our method. This user study showed that more than 90% of subjects agree with the code clones found by the method. Therefore, results so far indicate that sequence of method calls analysis is a valid strategy for code clone detection.