Two Basic Correctness Properties for ATL Transformations: Executability and Coverage (MtATL 2011)

Two Basic Correctness Properties for Transformations:

Executability and Coverage

Elena PlanasJordi Cabot

Cristina Gómez

Universitat Oberta de Catalunya (Spain)École des Mines de Nantes – INRIA (France)Universitat Politècnica de Catalunya (Spain)

MtATL 2011: 3rd International Workshop on Model Transformation with ATLJuly 1st, 2011 - Zürich, Switzerland

model transformations play a key role with the emergence of MDE.

the quality of the transformation process depends on the quality of the model transformations.

Related work

tools

analysis

testinglightweigh

t verificatio

n1/20

Define two basic correctness properties of model transformations rulesPropose a method to check these properties

goal

Lightweight (efficient) verification method Feedback suggesting possible corrections

method features

matched rules (declarative rules)focus

2/20

Property #1:

weak executability of an rule

3/20

An rule is weakly executable if it has a chance of being successfully executed (the rule’s execution generates a target model consistent with the target metamodel integrity constraints).Source

MetaModel

Target MetaMod

el

rule

Conf

orm

s To

Conf

orm

s To

4/20

rule Person2Student { from p: PersonMM!Person to s: StudentMM!Student ( name p.name college c ), c: StudentMM!College ( name p.collegeName )}

rule

Person

name: Stringage: IntegercollegeName: String

**

Knows

{Sym}

PersonMM

Student

name: StringSubject* IsEnrolledIn 1..*

id: String

College

name: String* StudiesAt 1

StudentMM

name: Erikage: 21collegeName: UOC

name: Erik

name: UOC

Studie

sAt

NOT

Con

form

s To

Conf

orm

s To

5/20

A

dependency

6/20

from an update up1 to another update up2 expresses that up2 must be included in all rules where up1 appears to avoid violating the metamodel constraints.

A

dependency

6/20

A

dependency

Create a new object… to o: TargetMM!A …

Initialize its mandatory attributes… to o: TargetMM!A( attrA value) …

Create its mandatory links… to o: TargetMM!A( b obj) …

Every time we… we must… … and…

TargetMM

B* 1

attrB: Type

A

attrA: Type

6/20

Compute dependencies

Mapdependencies

1

All dependenciesmapped?

2

rule

ruleis weakly executable

ruleis not weakly executable

FEEDBACK

no yes

7/20



Mapdependencies

1


2

rule

is weakly executable


FEEDBACK

no yes

rule

Subject* IsEnrolledIn 1..*

id: String

College


Student

name: String

rule

Create a new Student requires:Initialize its name attributeCreate 1 link of StudiesAt associationCreate at least 1 link of IsEnrolledIn association

Create a new College requires:Initialize its name attribute

Dependencies

8/20


Mapdependencies

1

2

rule




FEEDBACK

no yes

DependenciesCreate a new Student requires:

Initialize its name attributeCreate 1 link of StudiesAt associationCreate at least 1 link of IsEnrolledIn association


rule


9/20


Mapdependencies

1

2

rule




FEEDBACK

no yes




rule


9/20


Mapdependencies

1

2

rule




FEEDBACK

no yes




rule


9/20


Mapdependencies

1

2

rule




FEEDBACK

no yes




rule


9/20


Mapdependencies

1

2

rule




FEEDBACK

no yes




rule


9/20


Mapdependencies

1

2

rule





rule


FEEDBACK

no


yes


9/20

is not Weakly Executable

rule Person2Student

ERROR:


Mapdependencies

1

2

rule





rule


FEEDBACK

no


yes

AD

D F

EED

BA

CK


9/20

is not Weakly Executable

rule Person2Student

ERROR:

Property #2:

coverage of an rule set

10/20

A set of rules is

covering if it allows addressing all elements of the source and target metamodels.

source perspective

source-coverage

target perspective

target-coverage

11/20

A set of rules is source-covering when all elements of the source metamodel may be navigated throught the execution of these rules.

…is not source-covering (warning)

rule’s set

rule Person2Student { from p: PersonMM!Person to s: StudentMM!Student ( name p.name, college c ), c: StudentMM!College ( name p.collegeName )}

Person

name: Stringage: IntegercollegeName: String

**

Knows

{Sym}

PersonMM

12/20

A set of rules is target-covering when all elements of the target metamodel may be created or initialized throught the execution of these rules.rule’s set

rule Person2Student { from p: PersonMM!Person to s: StudentMM!Student ( name p.name, college c ), c: StudentMM!College ( name p.collegeName )}

Student

name: StringSubject* IsEnrolledIn 1..*

id: String

College


StudentMM

…is not target-covering (warning) 13/20

Compute metamodel

elementsrule setFEEDBACK

Compute addressedelements

Compute non-addressed

elements

1 2 3

14/20

Compute metamodel




elements

1 2 3

14/20

Compute metamodel




elements

1 2 3

15/20

Person classname attribute (of Person)age attribute (of Person)collegeName attribute (of Person)Knows association

Student classname attribute (of Student)College classname attribute (of College)Subject classid attribute (of Subject)StudiesAt associationIsEnrolledIn association

Compute metamodel




elements

1 2 3

16/20



Is navigated?

Is created/initialized?

17/20

Compute metamodel




elements

1 2 3

Non-addressed

Non-addressed

Non-addressed

Non-addressed

Non-addressed

rule setis not sourcecovering

WARNING:

is not targetcovering

rule setWARNING:

Is navigated?

Is created/initialized?



Conclusions:

feedback

18/20

Further work:

weak executability coverage

feedbackAddress new correctness properties

Provide tool support

Address other types of rules 19/20

Elena Planas [email protected]

Thanks for your attention!

20/20

Technology

Two Basic Correctness Properties for ATL Transformations: Executability and Coverage (MtATL 2011)