Unified Modeling Language.docx

Unified Modeling Language.docx

《Unified Modeling Language.docx》由会员分享，可在线阅读，更多相关《Unified Modeling Language.docx（8页珍藏版）》请在冰豆网上搜索。

UnifiedModelingLanguage

UnifiedModelingLanguage

UnifiedModelingLanguage（UML）isastandardizedgeneral-purposemodelinglanguageinthefieldofobject-orientedsoftwareengineering.Thestandardismanaged,andwascreated,bytheObjectManagementGroup.ItwasfirstaddedtothelistofOMGadoptedtechnologiesin1997,andhassincebecometheindustrystandardformodelingsoftware-intensivesystems.

UMLincludesasetofgraphicnotationtechniquestocreatevisualmodelsofobject-orientedsoftware-intensivesystems.

Contents

∙1Overview

∙2History

o2.1BeforeUML1.x

o2.2UML1.x

o2.3UML2.x

∙3Topics

o3.1Softwaredevelopmentmethods

o3.2Modeling

o3.3Diagramsoverview

▪3.3.1Structurediagrams

▪3.3.2Behaviourdiagrams

▪3.3.3Interactiondiagrams

o3.4Metamodeling

∙4Criticisms

∙5UMLmodellingtools

∙6Seealso

∙7References

∙8Furtherreading

∙9Externallinks

Overview

TheUnifiedModelingLanguage（UML）isusedtospecify,visualize,modify,constructanddocumenttheartifactsofanobject-orientedsoftware-intensivesystemunderdevelopment.UMLoffersastandardwaytovisualizeasystem'sarchitecturalblueprints,includingelementssuchas:

∙activities

∙actors

∙businessprocesses

∙databaseschemas

∙（logical）components

∙programminglanguagestatements

∙reusablesoftwarecomponents.

UMLcombinestechniquesfromdatamodeling（entityrelationshipdiagrams）,businessmodeling（workflows）,objectmodeling,andcomponentmodeling.Itcanbeusedwithallprocesses,throughoutthesoftwaredevelopmentlifecycle,andacrossdifferentimplementationtechnologies.UMLhassynthesizedthenotationsoftheBoochmethod,theObject-modelingtechnique（OMT）andObject-orientedsoftwareengineering（OOSE）byfusingthemintoasingle,commonandwidelyusablemodelinglanguage.UMLaimstobeastandardmodelinglanguagewhichcanmodelconcurrentanddistributedsystems.UMLisadefactoindustrystandard,andisevolvingundertheauspicesoftheObjectManagementGroup（OMG）.

UMLmodelsmaybeautomaticallytransformedtootherrepresentations（e.g.Java）bymeansofQVT-liketransformationlanguages.UMLisextensible,withtwomechanismsforcustomization:

profilesandstereotypes.

History

Historyofobject-orientedmethodsandnotation.

BeforeUML1.x

AfterRationalSoftwareCorporationhiredJamesRumbaughfromGeneralElectricin1994,thecompanybecamethesourceforthetwomostpopularobject-orientedmodelingapproachesoftheday:

Rumbaugh'sObject-modelingtechnique（OMT）,whichwasbetterforobject-orientedanalysis（OOA）,andGradyBooch'sBoochmethod,whichwasbetterforobject-orienteddesign（OOD）.TheyweresoonassistedintheireffortsbyIvarJacobson,thecreatoroftheobject-orientedsoftwareengineering（OOSE）method.JacobsonjoinedRationalin1995,afterhiscompany,ObjectoryAB,wasacquiredbyRational.ThethreemethodologistswerecollectivelyreferredtoastheThreeAmigos.

In1996,Rationalconcludedthattheabundanceofmodelinglanguageswasslowingtheadoptionofobjecttechnology,sorepositioningtheworkonaunifiedmethod,theytaskedtheThreeAmigoswiththedevelopmentofanon-proprietaryUnifiedModelingLanguage.RepresentativesofcompetingobjecttechnologycompanieswereconsultedduringOOPSLA'96;theychoseboxesforrepresentingclassesratherthanthecloudsymbolsthatwereusedinBooch'snotation.

UnderthetechnicalleadershipoftheThreeAmigos,aninternationalconsortiumcalledtheUMLPartnerswasorganizedin1996tocompletetheUnifiedModelingLanguage（UML）specification,andproposeitasaresponsetotheOMGRFP.TheUMLPartners'UML1.0specificationdraftwasproposedtotheOMGinJanuary1997.DuringthesamemonththeUMLPartnersformedaSemanticsTaskForce,chairedbyCrisKobrynandadministeredbyEdEykholt,tofinalizethesemanticsofthespecificationandintegrateitwithotherstandardizationefforts.Theresultofthiswork,UML1.1,wassubmittedtotheOMGinAugust1997andadoptedbytheOMGinNovember1997.

UML1.x

Asamodelingnotation,theinfluenceoftheOMTnotationdominates（e. g.,usingrectanglesforclassesandobjects）.ThoughtheBooch"cloud"notationwasdropped,theBoochcapabilitytospecifylower-leveldesigndetailwasembraced.TheusecasenotationfromObjectoryandthecomponentnotationfromBoochwereintegratedwiththerestofthenotation,butthesemanticintegrationwasrelativelyweakinUML1.1,andwasnotreallyfixeduntiltheUML2.0majorrevision.

ConceptsfrommanyotherOOmethodswerealsolooselyintegratedwithUMLwiththeintentthatUMLwouldsupportallOOmethods.Manyothersalsocontributed,withtheirapproachesflavouringthemanymodelsoftheday,including:

TonyWassermanandPeterPircherwiththe"Object-OrientedStructuredDesign（OOSD）"notation（notamethod）,RayBuhr's"SystemsDesignwithAda",ArchieBowen'susecaseandtiminganalysis,PaulWard'sdataanalysisandDavidHarel's"Statecharts";asthegrouptriedtoensurebroadcoverageinthereal-timesystemsdomain.Asaresult,UMLisusefulinavarietyofengineeringproblems,fromsingleprocess,singleuserapplicationstoconcurrent,distributedsystems,makingUMLrichbutalsolarge.

TheUnifiedModelingLanguageisaninternationalstandard:

ISO/IEC19501:

2005Informationtechnology–OpenDistributedProcessing–UnifiedModelingLanguage（UML）Version1.4.2

UML2.x

UMLhasmaturedsignificantlysinceUML1.1.Severalminorrevisions（UML1.3,1.4,and1.5）fixedshortcomingsandbugswiththefirstversionofUML,followedbytheUML2.0majorrevisionthatwasadoptedbytheOMGin2005.

AlthoughUML2.1wasneverreleasedasaformalspecification,versions2.1.1and2.1.2appearedin2007,followedbyUML2.2inFebruary2009.UML2.3wasformallyreleasedinMay2010.UML2.4isinthebetastageasofMarch2011.

TherearefourpartstotheUML2.xspecification:

1.TheSuperstructurethatdefinesthenotationandsemanticsfordiagramsandtheirmodelelements

2.TheInfrastructurethatdefinesthecoremetamodelonwhichtheSuperstructureisbased

3.TheObjectConstraintLanguage（OCL）fordefiningrulesformodelelements

4.TheUMLDiagramInterchangethatdefineshowUML2diagramlayoutsareexchanged

Thecurrentversionsofthesestandardsfollow:

UMLSuperstructureversion2.3,UMLInfrastructureversion2.3,OCLversion2.2,andUMLDiagramInterchangeversion1.0.

AlthoughmanyUMLtoolssupportsomeofthenewfeaturesofUML2.x,theOMGprovidesnotestsuitetoobjectivelytestcompliancewithitsspecifications.

Topics

Softwaredevelopmentmethods

UMLisnotadevelopmentmethodbyitself;however,itwasdesignedtobecompatiblewiththeleadingobject-orientedsoftwaredevelopmentmethodsofitstime（forexampleOMT,Boochmethod,Objectory）.SinceUMLhasevolved,someofthesemethodshavebeenrecasttotakeadvantageofthenewnotations（forexampleOMT）,andnewmethodshavebeencreatedbasedonUML,suchasIBMRationalUnifiedProcess（RUP）.OthersincludeAbstractionMethodandDynamicSystemsDevelopmentMethod.

Modeling

ItisimportanttodistinguishbetweentheUMLmodelandthesetofdiagramsofasystem.Adiagramisapartialgraphicrepresentationofasystem'smodel.Themodelalsocontainsdocumentationthatdrivesthemodelelementsanddiagrams（suchaswrittenusecases）.

UMLdiagramsrepresenttwodifferentviewsofasystemmodel:

∙Static（orstructural）view:

emphasizesthestaticstructureofthesystemusingobjects,attributes,operationsandrelationships.Thestructuralviewincludesclassdiagramsandcompositestructurediagrams.

∙Dynamic（orbehavioral）view:

emphasizesthedynamicbehaviorofthesystembyshowingcollaborationsamongobjectsandchangestotheinternalstatesofobjects.Thisviewincludessequencediagrams,activitydiagramsandstatemachinediagrams.

UMLmodelscanbeexchangedamongUMLtoolsbyusingtheXMIinterchangeformat.

Diagramsoverview

UML2.2has14typesofdiagramsdividedintotwocategories.Sevendiagramtypesrepresentstructuralinformation,andtheothersevenrepresentgeneraltypesofbehavior,includingfourthatrepresentdifferentaspectsofinteractions.Thesediagramscanbecategorizedhierarchicallyasshowninthefollowingclassdiagram:

UMLdoesnotrestrictUMLelementtypestoacertaindiagramtype.Ingeneral,everyUMLelementmayappearonalmostalltypesofdiagrams;thisflexibilityhasbeenpartiallyrestrictedinUML2.0.UMLprofilesmaydefineadditionaldiagramtypesorextendexistingdiagramswithadditionalnotations.

Inkeepingwiththetraditionofengineeringdrawings,acommentornoteexplainingusage,constraint,orintentisallowedinaUMLdiagram.

Structurediagrams

Structurediagramsemphasizethethingsthatmustbepresentinthesystembeingmodeled.Sincestructurediagramsrepresentthestructure,theyareusedextensivelyindocumentingthesoftwarearchitectureofsoftwaresystems.

∙Classdiagram:

describesthestructureofasystembyshowingthesystem'sclasses,theirattributes,andtherelationshipsamongtheclasses.

∙Componentdiagram:

describeshowasoftwaresystemissplitupintocomponentsandshowsthedependenciesamongthesecomponents.

∙Compositestructurediagram:

describestheinternalstructureofaclassandthecollaborationsthatthisstructuremakespossible.

∙Deploymentdiagram:

describesthehardwareusedinsystemimplementationsandtheexecutionenvironmentsandartifactsdeployedonthehardware.

∙Objectdiagram:

showsacompleteorpartialviewofthestructureofanexamplemodeledsystemataspecifictime.

∙Packagediagram:

describeshowasystemissplitupintol