AValidatedSetofSmellsinMVCArchitectures

Maurício Aniche,GabrieleBavota,ChristophTreude,Arie vanDeursen,MarcoGerosa@mauricioaniche,@gbavota,@ctreude,@avandeursen,@gerosa_marco

ICSME2016 2

Let’simprovethatfeature… Ohno!Codethere

sucks!

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Lookforcodesmells,youngpadawan!

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TakealookatthisGodClass!

Nah…

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WhataboutthisControllerwithmanyroutes?

Yeah,thisisaproblem!!!!

Interviews +surveys with

50 developers

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1. Layer-focused survey2. Role-focused survey3. Interviews with developers4. Expert review

Result: A catalogueof smells

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Promiscuous ControllerOffers too many actions

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BrainControllerToo much business logic

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Meddling ServiceQueries the database

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Brain RepositoryComplex logic (SQL or code)

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Laborious Repository Method

Many queries in a single method

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Fat RepositoryManages many entities

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Spring MVC in github

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Detection strategies

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3Q + 1.5IRQ

Smelly classes exist!

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Our studyICSME2016 18

RQ1. What is the impact of the proposed code smells on change-proneness of classes?

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RQ2. What is the impact of the proposed code smells on defect-proneness of classes?

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Smelly classes

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Clean classes

havechanged

have notchanged

havechanged

have notchanged

Isthisdifferencesignificant?

Are they smells?

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RQ3. Do developers perceive classes affected by the proposed code smells as problematic?

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• We collected perceptions of 17 developers

• 6 random classes of existing systems(2 T-smelly, 2 non smelly, 2 MVC smelly)

• Evaluate from 0 to 5 the severity of the problem

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Developers’ perceptions

Significantly different

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SCAM2016+ICSME2016=

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• Developersdocareaboutothertypesofsmells(contextualsmells)

• Bymeansofa4-stepapproach,wecoinedacatalogueofsmellsforMVCapps.

• Classesaffectedbythesesmellstendtobepronetochangeandtodefects.

• Developersclearlyperceivethesesmells.

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AValidatedSetofSmellsinMVCArchitectures

Maurício Aniche,GabrieleBavota,ChristophTreude,Arie vanDeursen,MarcoGerosa@mauricioaniche,@gbavota,@ctreude,@avandeursen,@gerosa_marco