Using Dynamic Time Warping to Detect Clones in Software Systems

Software clone detection is a widely researched area over the last two decades. Code clones are fragments of code judged similar by some metric of similarity. This paper proposes an approach for code clone detection using dynamic time warping technique (i.e., DTW). DTW is a well-known algorithm for aligning and measuring similarity of time series and it has been found effective in many domains where similarity plays an important role such as speech and gesture recognition. The proposed approach finds clones in three steps. First software modules are extracted. Then, the extracted modules are turned to time series. Finally, the time series are compared using the DTW algorithm to find clones. The results of the experiment conducted on a well-known Benchmark show that the approach can detect clones effectively in software systems.

Find Me if You Can: Deep Software Clone Detection by Exploiting the Contest between the Plagiarist and the Detector

Code clone is common in software development, which usually leads to software defects or copyright infringement. Researchers have paid significant attention to code clone detection, and many methods have been proposed. However, the patterns for generating the code clones do not always remain the same. In order to fool the clone detection systems, the plagiarists, known as the clone creator, usually conduct a series of tricky modifications on the code fragments to make the clone difficult to detect. The existing clone detection approaches, which neglects the dynamics of the “contest” between the plagiarist and the detectors, is doomed to be not robust to adversarial revision of the code. In this paper, we propose a novel clone detection approach, namely ACD, to mimic the adversarial process between the plagiarist and the detector, which enables us to not only build strong a clone detector but also model the behavior of the plagiarists. Such a plagiarist model may in turn help to understand the vulnerability of the current software clone detection tools. Experiments show that the learned policy of plagiarist can help us build stronger clone detector, which outperforms the existing clone detection methods.

A Mutation Operator-Based Scenario for Evaluating Software Clone Detection Tools and Techniques

Over the past few years, several software clone detection tools and techniques have been introduced by numerous researchers. The software clone detection techniques and tools are based on their numerous attributes and sub-attributes which make them difficult to complete a comparative study. Therefore, the authors propose a mutation operator-based editing taxonomy for generating different software clone types. In addition, a hypothetical scenario is developed using mutation operator-based editing taxonomy and this hypothetical scenario is used to evaluate various software clone detection techniques and tools. Further, the existing evaluation criterion is extended by the hypothetical scenario which is clearly represented by the analysis of results.

Positive and Unlabeled Learning for Detecting Software Functional Clones with Adversarial Training

Software clone detection is an important problem for software maintenance and evolution and it has attracted lots of attentions. However, existing approaches ignore a fact that people would label the pairs of code fragments as \emph{clone} only if they happen to discover the clones while a huge number of undiscovered clone pairs and non-clone pairs are left unlabeled. In this paper, we argue that the clone detection task in the real-world should be formalized as a Positive-Unlabeled (PU) learning problem, and address this problem by proposing a novel positive and unlabeled learning approach, namely CDPU, to effectively detect software functional clones, i.e., pieces of codes with similar functionality but differing in both syntactical and lexical level, where adversarial training is employed to improve the robustness of the learned model to those non-clone pairs that look extremely similar but behave differently. Experiments on software clone detection benchmarks indicate that the proposed approach together with adversarial training outperforms the state-of-the-art approaches for software functional clone detection.