Skip to main content
Springer Nature Link
Log in

Is cloned code really stable?

  • Published:
Empirical Software Engineering Aims and scope Submit manuscript

Abstract

Clone has emerged as a controversial term in software engineering research and practice. The impact of clones is of great importance from software maintenance perspectives. Stability is a well investigated term in assessing the impacts of clones on software maintenance. If code clones appear to exhibit a higher instability (i.e., higher change-proneness) than non-cloned code, then we can expect that code clones require higher maintenance effort and cost than non-cloned code. A number of studies have been done on the comparative stability of cloned and non-cloned code. However, these studies could not come to a consensus. While some studies show that code clones are more stable than non-cloned code, the other studies provide empirical evidence of higher instability of code clones. The possible reasons behind these contradictory findings are that different studies investigated different aspects of stability using different clone detection tools on different subject systems using different experimental setups. Also, the subject systems were not of wide varieties. Emphasizing these issues (with several others mentioned in the motivation) we have conducted a comprehensive empirical study where we have - (i) implemented and investigated seven existing methodologies that explored different aspects of stability, (ii) used two clone detection tools (NiCad and CCFinderX) to implement each of these seven methodologies, and (iii) investigated the stability of three types (Type-1, Type-2, Type-3) of clones. Our investigation on 12 diverse subject systems covering three programming languages (Java, C, C#) with a list of 8 stability assessment metrics suggest that (i) cloned code is often more unstable (change-prone) than non-cloned code in the maintenance phase, (ii) both Type 1 and Type 3 clones appear to exhibit higher instability than Type 2 clones, (iii) clones in Java and C programming languages are more change-prone than the clones in C#, and (iv) changes to the clones in procedural programming languages seem to be more dispersed than the changes to the clones in object oriented languages. We also systematically replicated the original studies with their original settings and found mostly equivalent results as of the original studies. We believe that our findings are important for prioritizing code clones from management perspectives.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20
Fig. 21
Fig. 22
Fig. 23
Fig. 24
Fig. 25
Fig. 26
Fig. 27
Fig. 28
Fig. 29
Fig. 30
Fig. 31
Fig. 32
Fig. 33
Fig. 34
Fig. 35
Fig. 36
Fig. 37
Fig. 38
Fig. 39
Fig. 40
Fig. 41

Similar content being viewed by others

Notes

  1. SourceForge: http://sourceforge.net/

References

  • Aversano L, Cerulo L, Penta MD (2007) How clones are maintained: an empirical study. In: Proc CSMR, pp 81–90

  • Bakota T, Ferenc R, Gyimothy T (2007) Clone smells in software evolution. In: Proc ICSM, pp 24–33

  • Barbour L, Khomh F, Zou Y (2011) Late propagation in software clones. In: Proc ICSM, pp 273–282

  • Barbour L, Khomh F, Zou Y (2013) An empirical study of faults in late propagation clone genealogies. J Softw Evol Process 25(11):1139–1165

    Article  Google Scholar 

  • Bettenburg N, Shang W, Ibrahim W, Adams B, Zou Y, Hassan A (2009) An empirical study on inconsistent changes to code clones at release level. In: Proc WCRE, pp 85–94

  • Cai D, Kim M (2011) An empirical study of long-lived code clones. In: Proc FASE/ETAPS, pp 432–446

  • Chatterji D, Carver JC, Kraft NA (2016) Code clones and developer behavior: results of two surveys of the clone research community. Empir Softw Eng 21(4):1476–1508

    Article  Google Scholar 

  • Cordy JR, Roy CK (2011) The NiCad Clone Detector. In: Proc ICPC (Tool Demo Track), pp 219–220

  • Göde N, Harder J (2011) Clone Stability. In: Proc CSMR, pp 65–74

  • Göde N, Koschke R (2009) Incremental clone detection. In: Proc CSMR, pp 219–228

  • Göde N, Koschke R (2010) Studying clone evolution using incremental clone detection. JSME 25(2):165–192

    Google Scholar 

  • Göde N, Koschke R (2011) Frequency and risks of changes to clones. In: Proc ICSE, pp 311–320

  • Harder J, Göde N (2013) Cloned code: stable code. J Softw Evol Process 25(10):1063–1088

    Article  Google Scholar 

  • Higo Y, Kusumoto S (2009) Significant and scalable code clone detection with program dependency graph. In: Proc WCRE, pp 315–316

  • Hordijk W, Ponisio M, Wieringa R (2009) Harmfulness of code duplication—a structured review of the evidence. In: Proc EASE, pp 88–97

  • Hotta K, Sano Y, Higo Y, Kusumoto S (2010) Is duplicate code more frequently modified than non-duplicate code in software evolution?: an empirical study on open source software. In: Proc EVOL/IWPSE, pp 73–82

  • Islam JF, Mondal M, Roy CK (2016) Bug replication in code clones: an empirical study. In: Proc. SANER, pp 68–78

  • Jarzabek S, Xu Y (2010) Are clones harmful for maintenance? In: Proc IWSC, pp 73–74

  • Juergens E, Deissenboeck F, Hummel B, Wagner S (2009) Do code clones matter? In: Proc ICSE, pp 485–495

  • Kamiya T, Kusumoto S, Inoue K (2002) CCFinder: a multilinguistic token-based code clone detection system for large scale source code. TSE 28(7):654–670

    Google Scholar 

  • Kapser C, Godfrey MW (2008) “Cloning considered harmful” considered harmful: patterns of cloning in software. ESE 13(6):645–692

    Google Scholar 

  • Kim M, Sazawal V, Notkin D, Murphy GC (2005) An empirical study of code clone genealogies. In: Proc ESEC-FSE, pp 187–196

  • Krinke J (2007) A study of consistent and inconsistent changes to code clones. In: Proc WCRE, pp 170–178

  • Krinke J (2008) Is cloned code more stable than non-cloned code? In: Proc SCAM, pp 57–66

  • Krinke J (2011) Is cloned code older than non-cloned code? In: Proc IWSC, pp 28–33

  • Li J, Ernst MD (2011) CBCD: cloned buggy code detector. University of Washington Department of Computer Science and Engineering technical report UW-CSE-11-05-02. Seattle, May 2, 2011. Revised

  • Lozano A, Wermelinger M (2008) Assessing the effect of clones on changeability. In: Proc ICSM, pp 227–236

  • Lozano A, Wermelinger M (2010) Tracking clones’ imprint. In: Proc IWSC, pp 65–72

  • Lozano A, Wermelinger M, Nuseibeh B (2007) Evaluating the harmfulness of cloning: a change based experiment. In: Proc MSR, p 18

  • Mondal M, Rahman MS, Saha RK, Roy CK, Krinke J, Schneider KA (2011) An empirical study of the impacts of clones in software maintenance. In: Proc ICPC student research symposium track, pp 242–245

  • Mondal M, Roy CK, Rahman S, Saha RK, Krinke J, Schneider K A (2012a) Comparative stability of cloned and non-cloned code: an empirical study. In: Proc SAC, pp 1227–1234

  • Mondal M, Roy CK, Schneider KA (2012b) An empirical study on clone stability. ACR 12(3):20–36

    Google Scholar 

  • Mondal M, Roy CK, Schneider KA (2012c) Dispersion of changes in cloned and non-cloned code. In: Proc IWSC, pp 29–35

  • Mondal M, Roy CK, Schneider K (2014a) An insight into the dispersion of changes in cloned and non-cloned code: a genealogy based empirical study. SCP 95(4):445–468

    Google Scholar 

  • Mondal M, Roy CK, Schneider KA (2014b) Late propagation in near-miss clones: an empirical study. ECEASST 63:1–17

    Google Scholar 

  • Mondal M, Roy CK, Schneider K A (2015) A comparative study on the bug-proneness of different types of code clones. In: Proc ICSME, pp 91–100

  • Mondal M, Roy CK, Schneider KA (2016) A comparative study on the intensity and harmfulness of late propagation in near-miss code clone. Softw Qual J 24(4):883–915

    Article  Google Scholar 

  • Rahman F, Bird C, Devanbu P (2010) Clones: what is that smell? In: Proc MSR, pp 72–81

  • Rahman MS, Roy CK (2014) A change-type based empirical study on the stability of cloned code. In: Proc SCAM, pp 31–40

  • Rahman MS, Aryani A, Roy CK, Perin F (2013) On the relationships between domain-based coupling and code clones: an exploratory study. In: Proc ICSE NIER track, pp 1265–1268

  • Roy CK, Cordy JR (2008a) An empirical evaluation of function clones in open source software. In: Proc WCRE, pp 81–90

  • Roy CK, Cordy JR (2008b) NICAD: accurate detection of near-miss intentional clones using flexible pretty-printing and code normalization. In: Proc ICPC, pp 172–181

  • Roy CK, Cordy JR (2008c) Scenario-based comparison of clone detection techniques. In: Proc ICPC, pp 153–162

  • Roy CK, Cordy JR (2009) A mutation/injection-based automatic framework for evaluating code clone detection tools. In: Proc mutation, pp 157–166

  • Roy CK, Cordy JR, Koschke R (2009) Comparison and evaluation of code clone detection techniques and tools: a qualitative approach. SCP 2009(74):470–495

    MathSciNet  MATH  Google Scholar 

  • Roy CK, Zibran MF, Koschke R (2014) The vision of software clone management: past, present and future. In: Proc CSMR-18/WCRE-21 software evolution week, p 16

  • Saha RK, Asaduzzaman M, Zibran MF, Roy CK, Schneider KA (2010) Evaluating code clone genealogies at release level: an empirical study. In: Proc SCAM, pp 87–96

  • Saha RK, Roy CK, Schneider KA (2011) An automatic framework for extracting and classifying near-miss clone genealogies. In: Proc ICSM, pp 293–302

  • Selim GMK, Barbour L, Shang W, Adams B, Hassan AE, Zou Y (2010) Studying the impact of clones on software defects. In: Proc WCRE, pp 13–21

  • Thummalapenta S, Cerulo L, Aversano L, Penta MD (2009) An empirical study on the maintenance of source code clones. ESE 15(1):1–34

    Google Scholar 

  • Wang T, Harman M, Jia Y, Krinke J (2013) Searching for better configurations: a rigorous approach to clone evaluation. In: Proc ESEC/SIGSOFT FSE, pp 455–465

  • Wang X, Dang Y, Zhang L, Zhang D, Lan E, Mei H (2012) Can I clone this piece of code here? In: Proc ASE, pp 170–179

Download references

Author information

Authors and Affiliations

  1. Department of Computer Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

    Manishankar Mondal, Md Saidur Rahman, Chanchal K. Roy & Kevin A. Schneider

Authors
  1. Manishankar Mondal
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Md Saidur Rahman
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Chanchal K. Roy
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Kevin A. Schneider
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Manishankar Mondal.

Additional information

Communicated by: Miryung Kim

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Mondal, M., Rahman, M.S., Roy, C.K. et al. Is cloned code really stable?. Empir Software Eng 23, 693–770 (2018). https://doi.org/10.1007/s10664-017-9528-y

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10664-017-9528-y

Keywords

Search

Navigation

pFad - Phonifier reborn

Pfad - The Proxy pFad of © 2024 Garber Painting. All rights reserved.

Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.


Alternative Proxies:

Alternative Proxy

pFad Proxy

pFad v3 Proxy

pFad v4 Proxy