research-article

Does refactoring improve software structural quality? A longitudinal study of 25 projects

Authors:

Leonardo Sousa,

Alessandro Garcia,

Rohit GheyiAuthors Info & Claims

SBES '16: Proceedings of the XXX Brazilian Symposium on Software Engineering

Pages 73 - 82

https://doi.org/10.1145/2973839.2973848

Published: 19 September 2016 Publication History

Abstract

Code smells in a program represent indications of structural quality problems, which can be addressed by software refactoring. Refactoring is widely practiced by developers, and considerable development effort has been invested in refactoring tooling support. There is an explicit assumption that software refactoring improves the structural quality of a program by reducing its density of code smells. However, little has been reported about whether and to what extent developers successfully remove code smells through refactoring. This paper reports a first longitudinal study intended to address this gap. We analyze how often the commonly-used refactoring types affect the density of 5 types of code smells along the version histories of 25 projects. Our findings are based on the analysis of 2,635 refactorings distributed in 11 different types. Surprisingly, 2,506 refactorings (95.1%) did not reduce or introduce code smells. Thus, these findings suggest that refactorings lead to smell reduction less often than what has been reported. According to our data, only 2.24% of refactoring changes removed code smells and 2.66% introduced new ones. Moreover, several smells induced by refactoring tended to live long, i.e., 146 days on average. These smells were only eventually removed when smelly elements started to exhibit poor structural quality and, as a consequence, started to be more costly to get rid of.

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Cited By

Abdullah AlOmar E(2023)State of Refactoring Adoption: Better Understanding Developer Perception of Refactoring2023 IEEE/ACM 20th International Conference on Mining Software Repositories (MSR)10.1109/MSR59073.2023.00090(635-639)Online publication date: May-2023
https://doi.org/10.1109/MSR59073.2023.00090
Oliveira DAssunção WGarcia ABibiano ARibeiro MGheyi RFonseca BGrundy JPollock LPenta M(2023)The Untold Story of Code Refactoring Customizations in PracticeProceedings of the 45th International Conference on Software Engineering10.1109/ICSE48619.2023.00021(108-120)Online publication date: 14-May-2023
https://dl.acm.org/doi/10.1109/ICSE48619.2023.00021
Ouni AAlOmar EHamdi OCinnéide MMkaouer MSaied M(2023)On the impact of single and co-occurrent refactorings on quality attributes in android applicationsJournal of Systems and Software10.1016/j.jss.2023.111817205(111817)Online publication date: Nov-2023
https://doi.org/10.1016/j.jss.2023.111817
Show More Cited By

Index Terms

Does refactoring improve software structural quality? A longitudinal study of 25 projects
1. General and reference
  1. Cross-computing tools and techniques
    1. Metrics
2. Information systems
  1. Information systems applications

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SBES '16: Proceedings of the XXX Brazilian Symposium on Software Engineering

September 2016

167 pages

ISBN:9781450342018

DOI:10.1145/2973839

Editor:
Eduardo Santanda de Almeida

Copyright © 2016 ACM.

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]

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SBC: Brazilian Computer Society

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Association for Computing Machinery

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Publication History

Published: 19 September 2016

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SBES '16

SBES '16: 30th Brazilian Symposium on Software Engineering

September 19 - 23, 2016

Maringá, Brazil

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Overall Acceptance Rate 147 of 427 submissions, 34%

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Cited By

Abdullah AlOmar E(2023)State of Refactoring Adoption: Better Understanding Developer Perception of Refactoring2023 IEEE/ACM 20th International Conference on Mining Software Repositories (MSR)10.1109/MSR59073.2023.00090(635-639)Online publication date: May-2023
https://doi.org/10.1109/MSR59073.2023.00090
Oliveira DAssunção WGarcia ABibiano ARibeiro MGheyi RFonseca BGrundy JPollock LPenta M(2023)The Untold Story of Code Refactoring Customizations in PracticeProceedings of the 45th International Conference on Software Engineering10.1109/ICSE48619.2023.00021(108-120)Online publication date: 14-May-2023
https://dl.acm.org/doi/10.1109/ICSE48619.2023.00021
Ouni AAlOmar EHamdi OCinnéide MMkaouer MSaied M(2023)On the impact of single and co-occurrent refactorings on quality attributes in android applicationsJournal of Systems and Software10.1016/j.jss.2023.111817205(111817)Online publication date: Nov-2023
https://doi.org/10.1016/j.jss.2023.111817
Mohamed ASalah MEldefrawi M(2023)Code quality improvement using Aquila OptimizerJournal of Software: Evolution and Process10.1002/smr.2559Online publication date: 16-Mar-2023
https://doi.org/10.1002/smr.2559
AlOmar EPeruma AMkaouer MNewman COuni ALo DMcIntosh SNovielli N(2022)An exploratory study on refactoring documentation in issues handlingProceedings of the 19th International Conference on Mining Software Repositories10.1145/3524842.3528525(107-111)Online publication date: 23-May-2022
https://dl.acm.org/doi/10.1145/3524842.3528525
Hamdi OOuni ACinnéide MMkaouer M(2022)A longitudinal study of the impact of refactoring in android applicationsInformation and Software Technology10.1016/j.infsof.2021.106699140:COnline publication date: 22-Apr-2022
https://dl.acm.org/doi/10.1016/j.infsof.2021.106699
Alomar EWang TRaut VMkaouer MNewman COuni A(2022)Refactoring for reuse: an empirical studyInnovations in Systems and Software Engineering10.1007/s11334-021-00422-618:1(105-135)Online publication date: 15-Jan-2022
https://dl.acm.org/doi/10.1007/s11334-021-00422-6
Peruma ASimmons SAlOmar ENewman CMkaouer MOuni A(2022)How do i refactor this? An empirical study on refactoring trends and topics in Stack OverflowEmpirical Software Engineering10.1007/s10664-021-10045-x27:1Online publication date: 1-Jan-2022
https://dl.acm.org/doi/10.1007/s10664-021-10045-x
Hamdi OOuni AAlOmar EO Cinneide MMkaouer M(2021)An Empirical Study on the Impact of Refactoring on Quality Metrics in Android Applications2021 IEEE/ACM 8th International Conference on Mobile Software Engineering and Systems (MobileSoft)10.1109/MobileSoft52590.2021.00010(28-39)Online publication date: May-2021
https://doi.org/10.1109/MobileSoft52590.2021.00010
Rahad KBadreddin OMohsin Reza S(2021)The human in model‐driven engineering loop: A case study on integrating handwritten code in model‐driven engineering repositoriesSoftware: Practice and Experience10.1002/spe.295751:6(1308-1321)Online publication date: 18-Feb-2021
https://doi.org/10.1002/spe.2957
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