Confidential Page 1

KvK 53479335

Lichtfabriekplein 1, 2031 TE Haarlem

P.O. Box 2031 , 2002 CA Haarlem

+31 (0)88 248 1632, info@ximedes.com

www.ximedes.com

Meetup Sponsor:

Test Driven DevelopmentRefactor Safely

Haarlem Software Developer Meetup@mcbeelen

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Refactoring is a controlled technique for improving the design of an existing code base

Its essence is applyinga series of

small behavior-preserving transformations

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01-10-2015 Confidential Page 7http://pitest.org/

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BloatersLong methods, Many primitive fields, Complex conditionals

Object-Orientation AbusersSwitch-statements, Temporary Fields

Change PreventersBad names, Magic Numbers, Solution Sprawl

CouplersTrain wrecks, Feature Envy

DispensablesComments, Duplicate Code, Dead code

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Rename Field Rename MethodExtract MethodInline Method

Move Field Move Method

Introduce Parameter ObjectmakeAlive(x, y) makeAlive(coordinate)

Extract Class

Extract Interface

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Replace Conditional with Polymorphism

if (cell.isAlive()) {// handleAlive

} else {// handleDead

}

AliveCell.evolve() DeadCell. evolve()

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Decompose Conditional

if (income > 25000 && dept < 1000) {maxLoan = income * largeFactor;newLoad = maxLoad – debt;return newLoad * normalPercentage

} else {maxLoan = income * smallFactor;newLoad = maxLoad – debt;return newLoad * highPercentage

}

if (isCreditWorthy()) {calculateOptimistic()

} else {calculatePessimistic()

}

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1. You are here to LEARN. (and have fun)

2. Try to do your best.

3. Work in pairs.Find a partner in a similar programming language and operating system

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Preparation for the kata’s:Git clone:https://github.com/emilybache/

Tennis-Refactoring-Kata

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https://martinfowler.com/articles/workflowsOfRefactoring/

https://refactoring.guru/

https://sourcemaking.com/refactoring

References

Thanks for your attendance!

Global Day of Code Retreat: 18 November  

Haarlem Software Developer Meetup