A SURVEY ON CLONE DETECTION AND CLONE ANALYSIS

Journal of Emerging Technologies in Web Intelligence, 2014

In any programming language source code, the code that is repeated is called the clone. The clone detections have got much attention in the recent years. In literature there are a number of clone detection techniques have been proposed. These techniques includes CP-Miner, CC-Finder etc. each of these techniques attempts to detect the clone from the source code of various programming languages. In this study, we will provide comprehensive details of the various clone detection techniques proposed so far. These techniques have been critically evaluated based on a no of efficiency measure parameters. In our future work we will propose our own clone detection technique that will more efficient and accurate in terms of code clone detection from multiple programming languages.

— Code clones have been studied for long, and there is strong evidence that they are a major source of software faults. The copying of code has been studied within software engineering mostly in the area of clone analysis. Software clones are regions of source code which are highly similar; these regions of similarity are called clones, clone classes, or clone pairs In this paper a hybrid approach using metric based technique with the combination of text based technique for detection and reporting of clones is proposed. The Proposed work is divided into two stages selection of potential clones and comparing of potential clones using textual comparison. The proposed technique detects exact clones on the basis of metric match and then by text match.

Over the last decade many techniques and tools for software clone detection have been proposed. In this paper, we provide a qualitative comparison and evaluation of the current state-of-the-art in clone detection techniques and tools, and organize the large amount of information into a coherent conceptual framework. We begin with background concepts, a generic clone detection process and an overall taxonomy of current techniques and tools. We then classify, compare and evaluate the techniques and tools in two different dimensions. First, we classify and compare approaches based on a number of facets, each of which has a set of (possibly overlapping) attributes. Second, we qualitatively evaluate the classified techniques and tools with respect to a taxonomy of editing scenarios designed to model the creation of Type-1, Type-2, Type-3 and Type-4 clones. Finally, we provide examples of how one might use the results of this study to choose the most appropriate clone detection tool or technique in the context of a particular set of goals and constraints. The primary contributions of this paper are: (1) a schema for classifying clone detection techniques and tools and a classification of current clone detectors based on this schema, and (2) a taxonomy of editing scenarios that produce different clone types and a qualitative evaluation of current clone detectors based on this taxonomy.

International Journal of Computer Applications, 2014

Code clones are the codes which have same code in the system and so it is difficult to locate all the same codes in the system when any change is to be done. Researchers have proved that almost 70% of the effort done during maintenance is just because of the occurrence the clones in the system. A number of approaches had been given earlier to detect various types of clones . This paper presents the systematic literature review of all the detection approaches researched so far. Along with it this paper also gives the advantages to implement them and also all the defects due to which they were not able to completely detect the clones. It also gives a novel approach to automatically detect the clones irrespective of the matter that whether the code is in same order or any statement has been inserted, deleted or modified in the code fragment.

International Journal for Research in Applied Science and Engineering Technology IJRASET, 2020

In software development process, coping of existing code fragment and pasting them with or without modification may be a frequent process. Clone means copy of an ingenious form or duplicate. Software clone detection is vital to scale back the software maintenance cost and to acknowledge the software during a better way. There are many software code clone detection techniques like text based, token-based, Abstract Syntax tree based etc. and they are used to spot and finding the existence of clones in software system. One of the approach is token based comparisons of two programs to detect code clone. Our technique uses the token-based approach using hashing algorithm by analysis of two source codes in the process of finding clones among them and the percentage of cloning is reported as result.

— Many techniques for detecting duplicated source code (software clones) have been proposed in the software reengineering literature. However, comparison of these techniques in terms of performance is not widely studied. There are four general categories for clone detection techniques; textual, lexical, syntactic, and semantic. This report presents an experiment that evaluates different clone detectors based on four Java programs of small to medium size scales. These subject systems have been used in the recent literature, and can be considered as standard systems for this purpose. At least one clone detection tool has been tested for each category. The comparison of different techniques is done based on performance metrics for clone detection tools. The most widely used metrics, precision and recall, have been used to calculate quantitative values for the performance of different techniques so that they can be compared with each other. The reference clones used in the comparison are those in the Bellon corpus. Our goal was to only evaluate systems that were not previously evaluated using Bellon benchmark, and not to replicate the previous works in our main experiment.

2020

Code clones are novel subtle way to deal with issues pertaining from one territory module to another fragment or module. They are increasing the rate of peril in bug duplication within each code that has a copy, whenever there was a bug in wellspring of clone. The clone in code is equivalent to or indistinct code in the original source code that is made either by reproduction or a couple of changes. Clone is an indefatigable sort of programming reuses that effect on help of enormous programming. Till now, the researchers have underlined on perceiving type 1, type 2, and type 3 sort of clones. The present code clone area devices are utilized to perceive source code cloning present within them. Throughout this paper, a review is done on programming clone area to assess cross breed strategy subject to various parameters. Rather than using single technique on the code, creamer methodology is being used, suggests two strategies are being solidified together. We can achieve increasingly e...

In software upgradation code clones are regularly utilized. So, we can contemplate on code location strategies goes past introductory code. In condition of-craftsmanship on clone programming study, we perceived the absence of methodical overview. We clarified the earlier research-in view of deliberate and broad database find and the hole of research for additionally think about. Software support cost is more than outlining cost. Code cloning is useful in several areas like detecting library contents, understanding program, detecting malicious program, etc. and apart from pros several serious impact of code cloning on quality, reusability and continuity of software framework. In this paper, we have discussed the code clone and its evolution and classification of code clone. Code clone is classified into 4 types namely Type I, Type II, III and IV. The exact code as well as copied code is depicted in detail for each type of code clone. Several clone detection techniques such as: Text, token, metric, hybrid based techniques were studied comparatively. Comparison of detection tools such as: clone DR, covet, Duploc, CLAN, etc. based on different techniques used are highlighted and cloning process is also explained. Code clones are identical segment of source code which might be inserted intentionally or unintentionally. Reusing code snippets via copying and pasting with or without minor alterations is general task in software development. But the existence of code clones may reduce the design structure and quality of software like changeability, readability and maintainability and hence increase the continuation charges.

TELKOMNIKA Telecommunication Computing Electronics and Control, 2018

The activities of copy and paste fragments of code from a source code into the other source code is often done by software developers because it's easier than generate code manually. This behavior leads to the increase of effort to maintain the code. One of the detection methods of semantic cloning is based on the behavior of the code. The code behavior detected by observing at an input, output and the effects of the method. Methods with the same value of input, output, and effect will indicate that semantically the same. However, the detection method based on the input, output, and effect could not be used in a void method or method without parameters, another side comprehensively detection is required. The challenge is how to detect which variable in a method that acts as input, output, and effect. Detection of the variable input, output, and effects in a void method done using Program Dependence Graph. The use of clone detection methods semantically based on behavior can increase the agreement value.

Information and Software Technology, 2007

Maintaining software systems is becoming more difficult as the size and complexity of software increase. One factor that complicates software maintenance is the presence of code clones. A code clone is a code fragment that has identical or similar code fragments to it in the source code. Code clones are introduced for various reasons such as reusing code by 'copy and paste'. If modifying a code clone with many similar code fragments, we must consider whether to modify each of them. Especially for large-scale software, such a process is very complicated and expensive. In this paper, we propose methods of visualizing and featuring code clones to support their understanding in large-scale software. The methods have been implemented as a tool called Gemini, which has applied to an open source software system. Application results show the usefulness and capability of our system.