UnderstandingtheSQALEModel

Dr.EduardoMirandaCMU

February4th,2015

SQALEModel

2

CharacteristicSubcharacteristic Rule

Maintainability Readability Filesize(LOC)

Factorsandtypes

3

Rules

Filesize(LOC)

SQALEsHierarchies

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Indicesandconsolidateindices

5

Characteristic File1 File2 Filen Indices File1 File2 FilenReusability SRuI

Portability SPI

Maintainability 4,10

SMI 6 2 82,4 2,4

Security14,200 SSI 14 14

Efficiency SEI

Changeability SCI

Reliability SRI

Testability

STI 3 3 63,15

3,12

Consolidatedindices

S

C

T

I

=

3

S

C

R

I

=

3

S

C

C

I

=

3

S

C

E

I

=

3

S

C

S

I

=

9

S

C

M

I

=

9

S

C

P

I

=

9

S

C

R

u

I

=

9

S

C

T

I

=

0

S

C

R

I

=

0

S

C

C

I

=

0

S

C

E

I

=

0

S

C

S

I

=

0

S

C

M

I

=

2

S

C

P

I

=

2

S

C

R

u

I

=

2

S

C

T

I

=

3

S

C

R

I

=

3

S

C

C

I

=

3

S

C

E

I

=

3

S

C

S

I

=

1

7

S

C

M

I

=

1

7

S

C

P

I

=

1

7

S

C

R

u

I

=

1

7

Technicaldebt=SQI 9 2 17 28

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BusinessImpact

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CharacteristicSubcharacteristic File1 File2 Filen File1 File2 Filen SBII

Reusability

Portability

Maintainability Readability 4,10

14 4 182,4 2,4

Understandability

Security14,200 200 200

Efficiency

Changeability

Reliability

Testability Unittestingtestability

15 15 303,15

3,15

BusinessImpactIndex=SBII 29 4 215 248

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Strategies

7

AdaptedfromSourceCodeQualityEvaluation:TheSQALEmethod,Letouzey,2011

Areaofconcern

S

Q

A

L

E

r

e

c

o

m

m

e

n

d

a

t

i

o

n

2015(c)EduardoMiranda

SQALEPyramid:Discussion

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TheSQALEMethodforEvaluatingTechnicalDebtJeanLouisLetouzey,ICSE2012

Byfixingtestabilityfirstyouavoidtherecurrent,nonremediation costoftestingnoncomplianceseverytimeyourepairsomethinghigherupintheSQALEpyramid Thesearetheremediationcostsof

eachcharacteristic.Thesecostsdonotrecur. Onceyoufixthenoncompliancestheyaregone

Whilethepyramidmakessenseintermsofitslevels,impactshouldbemeasuredbythenonremediationcostandnotby

thecostoffixingit

2015(c)EduardoMiranda

Questions?

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