On Detection of Gapped Code Clones using Gap Locations

It is generally said that code clone is one of the factors to make software maintenance difficult. A code clone is a code portion in source files that is identical or similar to another. Clones are introduced because of various reasons such as reusing code by ‘copy-and-paste’ and so on. Since developers usually modify the copied-and-pasted code portions, there are some gaps between the original code portion and it. Here, we call such code portions include some gaps Gapped code clone. Up to the present, several code clone detection methods, which give consideration to such gap, have been proposed. However, it needs a lot of cost to detect all the gapped code clones. This paper proposes a new method to visualize the gapped code clones just as if they were actually detected, based on the detection results of conventional code clone. Using the proposed method, the developer can specify the target clones efficiently. Moreover, we implement the proposed method into the maintenance support environment and conduct the experimental evaluation.