Genera&ngIntegrityPreservingAssocia&ons,

TheFirststeptoBiome

ReiniervanOostenVOOC

1VOOC

WhatisGipa

•  Gipaisasetofparameterizedimplementa&onlevelpaDernclasses.

•  Thesecanbeusedtogeneratemethodsandvariablesindomainmodelclasses.

•  ThepaDernsdescribeatypeofassocia&onandtheircomposingroles.

•  ThecurrentfocusofGipaisonstructureassocia&onslike1tonrela&onship.

•  ThefocusofGipaisonintegritypreserva&on.•  GipalookslikeMDA,butwithacompletedifferentfocus.

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Overview

•  Integrityindomainmodels•  Homeosta&corselfregula&ngapproach

•  PaDernsofintegritypreservingassocia&ons•  Specifyingassocia&ons•  Codegenera&onbasedonpaDernsandspecifica&on

•  Biologyinspiredobject‐orientedmodelingenvironment(Biome)

3VOOC

Theproblem:

•  Objectsmaychangetheirstateandthischangemayinfluencethestateofotherobjects.

•  Thestateofobjectsmaybeinconflictwiththestateofotherobjects.

•  Thisistheintegrityproblem•  Thismaybesolvedusingwithselfregula&ngorhomeosta&calgorithms.

•  Developmentofhomeosta&calgorithmsis&meconsumingandrequiresextensivetes&ng.

4VOOC

Integrityofobjectstructures

•  ClassicalERstructure•  Classicalproblembutnotsolved

•  Danglingpointers‐danglingobjects

•  Gipasolu&on:asetofrulesthatcanbeguardedbyhomeosta&cmethods.

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Integrityindomainmodels

•  3typesofdomainobjects:– Dataobjects(Integer,Timestamp,Classetc)

– Structureobjects(Collec&ons)– Modelobjects.

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3Rules

•  Dataobjectsshouldneverbechanged.•  Structureobjectsshouldbekeptprivate.•  Naviga&onbetweenmodelobjectsshouldalwaysbebidirec&onal.

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Advantageanddisadvantage

•  Advantages– Thedomainmodelisalwaysstable.

– ThereareanumberofpaDernssuppor&ngtherules.

•  Disadvantages– Codingisamorecomplicated,andaveryrepe&&ve(boring)task.

8VOOC

Solu&on

•  Aframeworkforgenera&ngpaDernbasedcode.– A(domain)modelspecifiedinapackageandanamespace

– Acollec&onofdomainclasses.– Acollec&onofassocia&ons.– Acollec&onofrolesforeachassocia&on,tobeimplementedbyasetofclasses.

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Associa&onpaDerns

•  ThepaDerndescribestheassocia&oninaparameterizedway.

•  Thenamesofmethodsandvariablesarestoredinroles.

•  Giventhespecifica&onoftheassocia&oninroles,methodsandvariablesaregenerated.

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VariouspaDerns

•  ToOne(=aDributeaccessintheVWbrowser)•  ToMany•  OneToOne•  OneToMany•  ManyToMany•  DoubleLink•  Tree

•  AnypaDernanybodywishestoimplement

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Verysimpleexample

1  paDernToOneGet

2  |stream|3  stream:=CodingStreamarguments:selfargs.

4  streamnextPutAll:‘{one,simple:s}5  ^{one,var:s}’.

6  ^streamselector‐>(streamcode}

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Specifica&onofanassocia&on

1  Theassocia&onpaDern2  Foreachrolespecifiedbytheassocia&on

paDern,thevariable‐andmethodnamebases.

3  XMLformat:GXD(GipaXMLDefini&on)

4  GXDcomparabletoclassdiagramdefini&oninUML.

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Example•  <GipaModelpackage="Gipa‐generatedoneToMany"namespace="GIPAExample”>

•  <gipaClassclassName="G_master_OneToMany">•  <fieldname="name"/>•  </gipaClass>

•  <gipaClassclassName="G_detail_OneToMany">•  <fieldname="name"/>•  </gipaClass>

•  <gipaAssocia&ondefini&on="OneToMany">•  <rolerole="one"variable="maten"single="maat"mul&ple="maten">•  <classclassName="G_master_OneToMany"/>•  </role>•  <rolerole="many"variable="master"keySelector="name"create="true">•  <classclassName="G_detail_OneToMany"/>•  </role>•  </gipaAssocia&on>•  </GipaModel>

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Generatedclassesandmethods

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Crucialmethodfor“many”

1  master:newMaster

2  newMaster=masterifTrue:[^newMaster].

3  masterifNotNil:[:old|

4  master:=nil.

5  oldremoveMaat:self].

6  newMasterifNotNil:[

7  master:=newMaster.

8  newMasteraddMaat:self]

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Crucialmethodfor“one”1  addMaat:newMaat2  |result|3  matenifNil:[maten:=OrderedCollec&onnew].4  result:=matendetect:[:item|itemname=newMaatname]5  ifNone:[ 6  matenadd:newMaat.7  newMaatmaster:self.8  ^newMaat].9  result==newMaatifTrue:[^newMaat]10  ifFalse:[11  ^GipaDuplicateKeyExcep&onraiseRequestWith:12  (Arraywith:resultwith:newMaat)]

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Result

•  Aclassdiagramcanbespecifiedingxdusinganxmleditorlikeoxygen

•  ThisgeneratesSmalltalkcode10&meslarger.

•  Thisgeneratedcodeisalreadytested.

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Worktodo

•  Gipaispartofalargerproject:Biome•  Biome:BiologyInspiredObject‐orientedModellingandEngineering

•  StructureofBiologicsciencecanbeusedasametaphoreforagileobject‐orienteddevelopmentanditsenvironment

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MappingBiologicsciencetoOOdevelopment

Fundaments

Celltheory Objecttheory

Genetheory ClassandRolePersistence

Researchareas Designareas

Physiology Processing,Algorithms,Unittes&ng

Structure Objectstructure,classdiagram

Taxonomy Inheritance

Ecology Interac&on,Associa&ons

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MappingII

ForceandDesign

Evolu&on Versions

Forces

Energy Efficiency

Homeostasis Notnamed,Oxenusedinstableparts,Selfregula&ngassocia&ons.

Homeostasis

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FocusofBiome

•  Modelling(Associa&onsandtheirpaDerns)•  Versioning(Evolu&onofmodels)

•  Persistancy•  IDE

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FocusofBiome(modelling)

•  Modellingofassocia&onsandassocia&onpaDerns

•  Implemen&ngrolesbyclasses

•  S&mula&nghomeostasistomakeassocia&onsandmodelsselfregula&ng

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FocusofBiome(versioning)

•  CurrentversioningVW=packages.•  AGipamodelisstoredinpackage.

•  Neededgranularity:associa&ons•  Neededversionassocia&on:– paDernversion‐>associa&onversion

•  Implemen&nganassocia&onversionisatransac&on

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FocusofBiome(Persistancy)

•  Associa&onsandrolescanbemappedtoGipadescrip&onsinGXD

•  Suppor&ngGlorpusingGXD•  Suppor&ngXMLmarshallingusingGXD

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FocusofBiome(IDE)

•  Suppor&ngAssocia&on‐Rolemodelling•  Suppor&ngAssocia&on‐RolepaDernmodelling

•  Suppor&ngversionimplementa&onastransac&on

•  Suppor&ngupda&ngassocia&onsasaresultofanassocia&onpaDernupgradeordowngrade.

26VOOC