AspectC#: An AOSD implementation for C

99 Pages·2012·2.23 MB·English

AspectC#: An AOSD implementation for C#.
HowardKim
DepartmentOfComputerScience
TrinityCollegeDublin
Adissertation submittedtothe UniversityOfDublin,
inpartial fulfilmentofthe requirementsforthe degreeof
Master ofScienceinComputerScience
September13, 2002
Declaration
Ideclare thatthe workdescribedin thisdissertationis, exceptwhere other-
wisestated,entirelymyownworkandhasnotbeensubmittedasanexercise
foradegreeatthisoranyotheruniversity.
Signed:
Date: September13,2002
Permission to lend and/or copy
IagreethatTrinityCollegeLibrarymaylendorcopythisdissertationupon
request.
Signed:
Date: September13,2002
Acknowledgments
I would firstly and most importantly like to thank Dr. Siobhn Clarke for in-
troducingmeinto the worldof AOSDandfor herhelp, advice andguidance both
insideandoutsideofficehoursthroughouttheyear.Herfaultlessguidanceallowed
me to be lucky enough to have a paper published at a workshop at the first inter-
national conference on AOSD in Utrecht in April 2002. Within the pages of this
dissertationliethebloomoftheseedsDr.Clarkelaidthroughoutmypostgraduate
yearstudyingunderher,anyerrors,omissionsormistakesaremineandshouldnot
reflectonher.Ihopethequalityofthisdissertationisasmallreflectiononthehard
workputintoitbyDrClarke,thankyou!
I’d like to thank: All the members of lecturers/staff at the Computer Science
Departmentfortheirhelp throughout allmy years at TCD. Tothe lecturersof the
NDS course for their help and advice throughout the year. The students of the
NDS class 2001-2002! Cormac for his help with AspectJ, Hyper/J and all things
withaspects.Martinforsittingbesidemeallyear!RichGreenaneforhishelpwith
Texnicandimages.SimonDobsonforhisadviceandhelpwithlatex.Owenforhis
helpwiththethesis.Toallmyfriendsfortheirsupport.
Finally but certainly not least, I’d like to thank my family. To my mother for
all her love and support. To my brothers Jong and Oisin for their proof reading,
suggestions,adviceandsupport.Thankyou!
Abstract
A majorproblemwithObject OrientedProgramming(OOP) isthat it cannotdeal
efficientlywithcrosscuttingconcerns.AspectOrientedSoftwareDevelopment(AOSD)
is a new methodology that tries to enable the extension of the separation of con-
cerns capabilities in software development. AOSD, which encompasses Aspect
OrientedProgramming(AOP),hopestoenablethedeveloperorarchitecttocapture
crosscuttingconcernsinamodularfashion.
Theobjectivesofthedissertationincludethedesign,implementationandeval-
uationofatoolthatenablesthemodularisationofcrosscuttingconcernswithinC#,
thatwehavecalled“AspectC#”.AspectC#must:
AllowthedevelopertouseAOPconstructswithinC#.
(cid:0)
MakenoexplicitlanguageextensionstoC#.
(cid:0)
Beextensibleforfuturedevelopment.
(cid:0)
AspectC# hopes to enable the developer to modularise crosscutting concerns
withinC#.Bymodularisingcrosscuttingconcernsthiswillleadtoaneasierdevel-
opmentandmaintenanceofapplications.
The evaluation included a small case study comparing an example using As-
pectC#andOOPwithC#.Webelievethecasestudyandtoolsupportsthecasefor
the use and promotion of AOSD. Special emphasis was placed on picking a real
world,easilyunderstoodexampleof theuseof thetool andwebelieve this repre-
sents an excellent introduction to some of the most widely used AOP and AOSD
techniques.
Contents
1 Introduction 11
1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.2 AddressingtheProblem . . . . . . . . . . . . . . . . . . . . . . . 11
1.3 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1.4 Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.5 ThesisOutline . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2 StateoftheArt 16
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.2 .NETFramework . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.2.1 Architecture. . . . . . . . . . . . . . . . . . . . . . . . . 17
2.2.2 Languages . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.2.3 BaseClassLibrary . . . . . . . . . . . . . . . . . . . . . 18
2.2.4 CommonLanguageRuntime(CLR) . . . . . . . . . . . . 21
2.3 AOSDTechnology . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.4 JavaAOPApproaches . . . . . . . . . . . . . . . . . . . . . . . 26
2.4.1 AspectJ . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.4.2 Hyper/J . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
2.5 .NETAOPApproaches . . . . . . . . . . . . . . . . . . . . . . . 36
2.5.1 CrossLanguageAspectWeaving(CLAW) . . . . . . . . 36
5
2.5.2 AOP# . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
2.5.3 Other.NETapproaches . . . . . . . . . . . . . . . . . . . 43
2.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
3 RequirementsandDesign 44
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
3.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
3.2.1 FunctionalRequirements . . . . . . . . . . . . . . . . . . 44
3.2.2 Non-FunctionalRequirements . . . . . . . . . . . . . . . 46
3.3 Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
3.3.1 DifferentApproaches . . . . . . . . . . . . . . . . . . . . 47
3.3.2 OurApproach. . . . . . . . . . . . . . . . . . . . . . . . 48
3.3.3 ProjectArchitecture . . . . . . . . . . . . . . . . . . . . 52
3.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
4 Implementation 58
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.2 AOPEngine . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.3 Parser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.4 AbstractSyntaxTree . . . . . . . . . . . . . . . . . . . . . . . . 61
4.5 Aspectweaver . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
4.5.1 DynamicCrosscuttingImplementation . . . . . . . . . . 63
4.5.2 StaticCrosscuttingImplementation . . . . . . . . . . . . 65
4.6 Compiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
4.7 AspectDeploymentDescriptor . . . . . . . . . . . . . . . . . . . 68
4.8 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
5 Evaluation 71
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.2 .NETasanAOSDplatform . . . . . . . . . . . . . . . . . . . . . 71
5.2.1 MetaData . . . . . . . . . . . . . . . . . . . . . . . . . . 72
5.2.2 Reflectionmechanism . . . . . . . . . . . . . . . . . . . 72
5.2.3 CodeDOM . . . . . . . . . . . . . . . . . . . . . . . . . 73
5.2.4 MSIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
5.3 EvaluationMethodology . . . . . . . . . . . . . . . . . . . . . . 73
5.4 AspectC#versusTheRest . . . . . . . . . . . . . . . . . . . . . 74
5.4.1 HowtheAOPsystemspecifiesaspects . . . . . . . . . . . 75
5.4.2 Compositionmechanismsthesystemprovides . . . . . . 75
5.4.3 Implementationmechanisms . . . . . . . . . . . . . . . . 76
5.4.4 Decoupling . . . . . . . . . . . . . . . . . . . . . . . . . 79
5.4.5 SoftwareProcess . . . . . . . . . . . . . . . . . . . . . . 79
5.4.6 Usability . . . . . . . . . . . . . . . . . . . . . . . . . . 80
5.5 AnExample:ABankAccount . . . . . . . . . . . . . . . . . . . 81
5.5.1 TheProblem . . . . . . . . . . . . . . . . . . . . . . . . 81
5.5.2 OOSolution . . . . . . . . . . . . . . . . . . . . . . . . 81
5.5.3 AspectC#Solution . . . . . . . . . . . . . . . . . . . . . 84
5.5.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
5.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
6 Conclusions 89
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
6.2 SummaryofObjectives . . . . . . . . . . . . . . . . . . . . . . . 89
6.3 Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.4 LimitationsofSystem . . . . . . . . . . . . . . . . . . . . . . . . 91
6.4.1 ParserLimitations . . . . . . . . . . . . . . . . . . . . . 91
6.4.2 CodeDOMLimitations . . . . . . . . . . . . . . . . . . . 92
6.4.3 SemanticLimitations . . . . . . . . . . . . . . . . . . . . 92
6.5 FutureWork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
6.5.1 Parser . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
6.5.2 CodeDOMGraph . . . . . . . . . . . . . . . . . . . . . . 93
6.5.3 SemanticsofAspectC# . . . . . . . . . . . . . . . . . . . 93
6.5.4 Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
6.5.5 Crosslanguageweaving . . . . . . . . . . . . . . . . . . 94
List of Figures
2.1 .NetFrameworkBlockDiagram. . . . . . . . . . . . . . . . . . . 18
2.2 CodeDOMHierarchy . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3 ExecutionModel.NetFramework. . . . . . . . . . . . . . . . . . 22
2.4 .NetTypeSystem. . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.5 .NetCompiling . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.6 AssemblyStructure . . . . . . . . . . . . . . . . . . . . . . . . . 24
2.7 Hyper/Joverview . . . . . . . . . . . . . . . . . . . . . . . . . . 32
2.8 ArchitectureAOP#. . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.1 DifferentAOPtoolapproaches. . . . . . . . . . . . . . . . . . . 47
3.2 ProjectArchitecture. . . . . . . . . . . . . . . . . . . . . . . . . 52
3.3 AOPEngineArchitecture. . . . . . . . . . . . . . . . . . . . . . 53
3.4 ParserClassDiagram. . . . . . . . . . . . . . . . . . . . . . . . 54
3.5 CompilerClassDiagram. . . . . . . . . . . . . . . . . . . . . . . 57
4.1 SequenceDiagramofASTrepresentation . . . . . . . . . . . . . 62
4.2 SequenceDiagramofAspectWeaver . . . . . . . . . . . . . . . 64
5.1 Bankaccountclassdiagram. . . . . . . . . . . . . . . . . . . . . 82
5.2 BankaccountAOPclassdiagram. . . . . . . . . . . . . . . . . . 84
5.3 NumberoflinesofcodefromOOsolution. . . . . . . . . . . . . 87
5.4 NumberoflinesofcodefromAOPsolution. . . . . . . . . . . . 87
9