Editing Code smell (section)

===Class-level smells===

*  ''Large class'', or a ''[[God object]]'': a [[Class (computer science)|class]] that contains too many types or contains many unrelated methods.{{fact|date=March 2025}}
* ''Refused bequest'': a class that [[Method overriding (programming)|override]]s a method of a base class in such a way that the [[contract (software)|contract]] of the [[base class]] is not honored by the [[derived class]], violating the [[Liskov substitution principle]].{{fact|date=March 2025}}
* ''Excessive use of literals'' or ''[[Magic number (programming)|magic numbers]]'': these should be coded as named constants, to improve readability and to avoid programming errors. Additionally, [[literal (computer programming)|literal]]s can and should be externalized into resource files/scripts, or other data stores such as databases where possible, to facilitate localization of software if it is intended to be deployed in different regions.<ref>{{Cite web|url=https://maximilianocontieri.com/code-smell-02-constants-and-magic-numbers|title=Constants and Magic Numbers|access-date=2020-11-03}}</ref>{{self published inline|date=March 2025|certain=y}}
* ''[[Downcasting]]'': a type cast which breaks the abstraction model; the abstraction may have to be refactored or eliminated.<ref>{{cite web |author=Miller, Jeremy |title=Downcasting is a code smell |url=http://codebetter.com/jeremymiller/2006/12/26/downcasting-is-a-code-smell/ |access-date=4 December 2014 |url-status=dead |archive-url=https://web.archive.org/web/20190216193452/http://codebetter.com/jeremymiller/2006/12/26/downcasting-is-a-code-smell/ |archive-date=16 February 2019 }}</ref>{{self published inline|date=March 2025|certain=y}}
* ''[[Data Clump (Code Smell)|Data clump]]'': Occurs when a group of variables are passed around together in various parts of the program. In general, this suggests that it would be more appropriate to formally group the different variables together into a single object, and pass around only the new object instead.<ref>{{Cite web|url=https://martinfowler.com/bliki/DataClump.html|title=DataClump|last=Fowler|first=Martin|access-date=2017-02-03}}</ref><ref>{{Cite web|url=https://sourcemaking.com/refactoring/smells/data-clumps|title=Design Patterns and Refactoring|website=sourcemaking.com|language=en|access-date=2017-02-04}}</ref>{{Unreliable source?|date=March 2025}}