Analysis and Design Learning Objectives Systems development life cycle Identify the four phases How it came about Methodology alternatives Team roles amp skill sets Objectoriented systems characteristics ID: 1028649
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1. Chapter 1:Introduction to SystemsAnalysis and Design
2. Learning ObjectivesSystems development life cycleIdentify the four phasesHow it came aboutMethodology alternativesTeam roles & skill setsObject-oriented systems characteristicsObject-oriented systems analysis & designThe Unified Process & its extensionsThe Unified Modeling Language (UML)
3. IntroductionWhy do we need a formal process?Failures occur (too) oftenCreating systems is not intuitiveProjects are late, over budget or delivered with fewer features than plannedThe System Analyst is the key personDesigns a system to add valueMust understand the business processesJob is rewarding, yet challengingRequires specific skill sets
4. Systems Development Life Cycle (SDLC)
5. The SDLC ProcessThe process consists of four phasesEach phase consists of a series of stepsEach phase is documented (deliverables)Phases are executed sequentially, incrementally, iteratively or in some other pattern
6. Questions to be AnsweredPlanning phaseWhy should we build this system?What value does it provide?How long will it take to build?Analysis phaseWho will use it?What should the system do for us?Where & when will it be used?Design phaseHow should we build it?
7. SDLC: The Planning PhaseProject InitiationDevelop/receive a system requestConduct a feasibility analysisProject ManagementDevelop the work planStaff the projectMonitor & control the project
8. SDLC: The Analysis PhaseDevelop an analysis strategyModel the current systemFormulate the new systemGather the requirementsDevelop a system conceptCreate a business model to represent:Business dataBusiness processesDevelop a system proposal
9. SDLC: The Design PhaseDevelop a design strategyDesign architecture and interfacesDevelop databases and file specificationsDevelop the program design to specify:What programs to writeWhat each program will do
10. SDLC: The Implementation PhaseConstruct the systemBuild it (write the programming code)Test itInstall systemTrain the usersSupport the system (maintenance)
11. SDLC: MethodologiesMethodology: a formalized approach to implementing the SDLCCategoriesProcess orientedData centeredObject-orientedStructuredRapid action developmentAgile development
12. Classes of MethodologiesStructured DevelopmentWaterfall DevelopmentParallel DevelopmentRapid Application DevelopmentPhasedPrototypingAgile DevelopmenteXtreme ProgrammingSCRUM
13. Which Methodology to Use?
14. The Systems Analyst: SkillsAgents of changeIdentify ways to improve the organizationMotivate & train othersSkills needed:Technical: must understand the technologyBusiness: must know the business processesAnalytical: must be able to solve problemsCommunications: technical & non-technical audiencesInterpersonal: leadership & managementEthics: deal fairly and protect confidential information
15. The Systems Analyst: RolesBusiness AnalystFocuses on the business issues Systems Analyst Focuses on the IS issues Infrastructure AnalystFocuses on the technical issues Change Management Analyst Focuses on the people and management issuesProject ManagerEnsures that the project is completed on time and within budget
16. Object-Oriented Systems Analysis & DesignAttempts to balance data and processUtilizes the Unified Modeling Language (UML) and the Unified Process Characteristics of OOAD:Use-case DrivenArchitecture CentricIterative and Incremental
17. Characteristics of Object-Oriented SystemsClasses & ObjectsObject (instance): instantiation of a classAttributes: information that describes the classState: describes its values and relationships at a point in timeMethods & MessagesMethods: the behavior of a classMessages: information sent to an object to trigger a method (procedure call)
18. Characteristics of Object-Oriented Systems (cont.)Encapsulation & information hidingEncapsulation: combination of process & dataInformation hiding: functionality is hiddenInheritanceGeneral classes are created (superclasses)Subclasses can inherit data and methods from a superclass
19. Characteristics of Object-Oriented Systems (cont.)Polymorphism & dynamic bindingPolymorphism: the same message can have different meaningsDynamic binding: type of object is not determined until run-timeContrast with static binding
20. Object-Oriented Systems Analysis & DesignUse-case drivenUse-cases define the behavior of a systemEach use-case focuses on one business processArchitecture centricFunctional (external) view: focuses on the user’s perspectiveStatic (structural) view: focuses on attributes, methods, classes & relationshipsDynamic (behavioral) view: focuses on messages between classes and resulting behaviors
21. Object-Oriented Systems Analysis & Design (cont.)Iterative & incrementalUndergoes continuous testing & refinementThe analyst understands the system better over timeBenefits of OOSADBreak a complex system into smaller, more manageable modulesWork on modules individually
22. The Unified ProcessA specific methodology that maps out when and how to use the various UML techniques for object-oriented analysis and designA two-dimensional process consisting of phases and workflowsPhases are time periods in developmentWorkflows are the tasks that occur in each phaseActivities in both phases & workflows will overlap
23. The Unified Process
24. Unified Process PhasesInceptionFeasibility analyses performedWorkflows vary but focus is on business modeling & requirements gatheringElaborationHeavy focus on analysis & designOther workflows may be includedConstruction: Focus on programming (implementation)Transition--Focus on testing & deployment
25. Engineering WorkflowsBusiness modelingRequirementsAnalysisDesignImplementationTestingDeployment
26. Supporting WorkflowsProject managementConfiguration and change managementEnvironmentOperations and support*Infrastructure management** Part of the enhanced unified process
27. Extensions to the Unified ProcessThe Unified Process does not include:StaffingBudgetingContract managementMaintenanceOperationsSupportCross- or inter-project issues
28. Extensions to the Unified Process (cont.)Add a Production Phase to address issues after the product has been deployedNew Workflows:Operations & SupportInfrastructure managementModifications to existing workflows:Test workflowDeployment workflowEnvironment workflowProject Management workflowConfiguration & change management workflow
29. Unified Modeling LanguageProvides a common vocabulary of object-oriented terms and diagramming techniques rich enough to model any systems development project from analysis through implementationVersion 2.5 has 15 diagrams in 2 major groups:Structure diagramsBehavior diagrams
30. UML Structure DiagramsRepresent the data and static relationships in an information systemClassObjectPackageDeploymentComponentComposite structure
31. UML Behavior DiagramsDepict the dynamic relationships among the instances or objects that represent the business information systemActivitySequenceCommunicationInteraction overviewTimingBehavior state machineProtocol state machine,Use-case diagrams
32. SummaryAll systems development projects follow essentially the same process, called the system development life cycle (SDLC)System development methodologies are formalized approaches to implementing SDLCsThe systems analyst needs a variety of skills and plays a number of different rolesObject-oriented systems differ from traditional systems
33. SummaryObject-Oriented Systems Analysis and Design (OOSAD) uses a use-case-driven, architecture-centric, iterative, and incremental information systems development approachThe Unified Process is a two-dimensional systems development process described with a set of phases and workflowsThe Unified Modeling Language, or UML, is a standard set of diagramming techniques