Introduction to Computer Science_14_

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					                                        Objectives
   Explain the purpose and various phases of the
    traditional systems development life cycle (SDLC)
   Explain when to use an adaptive approach to the
    SDLC in place of the more predictive traditional
    SDLC
   Describe how the more adaptive Unified Process
    (UP) life cycle uses iterative and incremental
    development
   Explain the differences between a model, a tool, a
    technique, and a methodology
Object-Oriented Analysis and Design with the Unified Process   2
                    Objectives (continued)
      Describe the Unified Process as a comprehensive
       system development methodology that combines
       proven best practices with the iterative UP life cycle
      Describe the disciplines used in a UP development
       project
      Explain how automated tools are used in system
       development



Object-Oriented Analysis and Design with the Unified Process    3
   The Systems Development Life
              Cycle
 The entire process of building, deploying, using and
  updating an information system
 Two approaches:
    Predictive approach
       ◘ Assumes the development project can be planned and
         organized in advance and the new information system can be
         developed according to the plan
    Adaptive approach
       ◘ Assumes the project cannot be planned out completely in
         advance but be modified as it progress, especially after some
         preliminary development work
                          SDLC phases and objectives

      a) Traditional SDLC




                                SDLC Phases and Objectives

Object-Oriented Analysis and Design with the Unified Process   5
       b) The waterfall approach




                             The Waterfall Approach to the SDLC

Object-Oriented Analysis and Design with the Unified Process      6
       c) The overlap of system development activities




                          : Completion of major components
                          of project

Object-Oriented Analysis and Design with the Unified Process   7
          The Newer Adaptive Approaches to the
                        SDLC
    a) Spiral Model
     The spiral model:
        Cycles over and over again through development activities until a
          the project is complete
     Iteration of system development activities
        Iteration 1: SOME analysis, SOME design, SOME implementation
        Iteration 2: MORE analysis, MORE design, MORE implementation
        Iteration 3: EVEN MORE analysis, EVEN MORE design, EVEN
          MORE implementation
     All above process should be repeated until the system is closer to what is
      ultimately needed




Object-Oriented Analysis and Design with the Unified Process                      8
                                 The Spiral Life Cycle Model


Object-Oriented Analysis and Design with the Unified Process   9
b) Related approach : Incremental Development

Completes parts of a system in several iterations
 and then puts them into operation for users
This process is continuously and finally we can
 complete the last part and integrate it with the rest
The object oriented approach is always described
 as highly iterative
            The Unified Process Life Cycle
  UP life cycle
        Includes (4) phases which consist of iterations
        Iterations are “mini-projects”
  Inception: develop and refine system vision
  Elaboration: define requirements and core architecture
  Construction: continue design and implementation
  Transition: move the system into operational mode

Object-Oriented Analysis and Design with the Unified Process   11
                The Unified Process System Development Life Cycle




Object-Oriented Analysis and Design with the Unified Process        12
                                    UP Phases and Objectives



Object-Oriented Analysis and Design with the Unified Process   13
          Methodologies, Models, Tools and Techniques

         Tools: Helps to create models or other components
         required in the project




          CASE: Helps s system analyst complete development task

Object-Oriented Analysis and Design with the Unified Process       14
                        Some Models used in System Development




Object-Oriented Analysis and Design with the Unified Process     15
                     Some Techniques used in System Development


      Technique: A collection of guidelines that help an analyst
      complete a system development activity or task




Object-Oriented Analysis and Design with the Unified Process       16
            Relationships of Models, Tools, and Techniques in a System
                            Development Methodology




Object-Oriented Analysis and Design with the Unified Process             17
           The Unified Process as a System
             Development Methodology

    UP: object-oriented system development
     methodology
    Developed by Grady Booch, James Rumbaugh and
     Ivar Jacobson.




Object-Oriented Analysis and Design with the Unified Process   18
               UP Life Cycle with Phases, Iterations, and Disciplines

Object-Oriented Analysis and Design with the Unified Process            19
                          The UP Disciplines

      Six main UP development disciplines
            Business modeling, requirements, design,
             implementation, testing, and deployment
      Each iteration
            Similar to a mini-project
            Results in a completed portion of the system
      Three additional support disciplines
            Project management, configuration and change
             management, and environment

Object-Oriented Analysis and Design with the Unified Process   20
      a) Business Modeling
      Purpose: understand business environment

      Three major activities part of business modeling

            Understand the business environments

            Create the system vision

            Create business models


Object-Oriented Analysis and Design with the Unified Process   21
    b) Requirements
   Objective: document business requirements
   Key drivers of activities: discovery and understanding
   Requirements discipline and business modeling map
    to traditional systems analysis
   Activities list
         Gather detailed information
         Define functional and nonfunctional requirements
         Prioritize requirements
         Develop user interface dialogs
         Evaluate requirements with users
Object-Oriented Analysis and Design with the Unified Process   22
      c) Design
       Objective: design system based on requirements
       Six major activities in the design discipline
             Design support services architecture and
              deployment environment
             Design the software architecture
             Design use case realizations
             Design the database
             Design the system and user interfaces
             Design the system security and controls

Object-Oriented Analysis and Design with the Unified Process   23
      d) Implementation
      Objective: build or acquire needed system
       components

      Implementation activities

            Build software components

            Acquire software components

            Integrate software components

Object-Oriented Analysis and Design with the Unified Process   24
       e) Testing
      Testing is critical discipline
      Testing activities
            Define and conduct unit testing
            Define and conduct integration testing
            Define and conduct usability testing
            Define and conduct user acceptance testing
      In UP, acceptance testing occurs throughout the
       building phase
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   f) Deployment
    Goal: conduct activities to make system operational
    Deployment activities
          Acquire hardware and system software
          Package and install components
          Train users
          Convert and initialize data
    Deployment activities prominent in transition phase

Object-Oriented Analysis and Design with the Unified Process   26
      g) Project Management
      Most important support discipline
      Project management activities
            Finalize the system and project scope
            Develop the project and iteration schedule
            Identify project risks and confirm feasibility
            Monitor and control the project’s plan
            Monitor and control communications
            Monitor and control risks and outstanding issues
Object-Oriented Analysis and Design with the Unified Process    27
     h) Configuration and Change
             Management
      Configuration and change discipline pertains to:
            Requirements
            Design
            Source code
            Executables
      The two activities in this discipline
            Develop change control procedures
            Manage models and software components
Object-Oriented Analysis and Design with the Unified Process   28
       i) Environment
      Development environment includes
            Available facilities
            Design of the workspace
            Forums for team communication and interaction
      Environment discipline activities
            Select and configure the development tools
            Tailor the UP development process
            Provide technical support services

Object-Oriented Analysis and Design with the Unified Process   29
                 Tools to Support System
                      Development
  CASE (Computer Aided System Engineering)
        Contains da atabase repository for information system
        Set of tools that help analysts complete activities
        Sample artifacts: models, automatically generated code




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    A CASE Tool Repository Contains All Information About the System

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                Tools to Support System
                Development (continued)
      Microsoft Visio: emphasizes technical drawing
      Rational Rose
            CASE tool supporting object-oriented approach
            Strongly identified with UP methodology
      Together
            Pioneers round-trip engineering
                  ◘ synchronizes graphical models with generated
                    program code
            Leverages UML diagrams
Object-Oriented Analysis and Design with the Unified Process       32
                Tools to Support System
                Development (continued)
      Embarcadero Describe
            Visual Modeling
            Round-trip engineering

      Rational XDE Professional
            Integrates Microsoft Visual Studio.NET IDE
            Also provides visual modeling and round-trip

Object-Oriented Analysis and Design with the Unified Process   33
                                         Summary
   SDLC: set of activities required to complete system
    development project

   Predictive SDLC: executes project in sequential phases
    (waterfall approach)

   Adaptive SDLC: accommodates change and phase overlap

   Spiral SDLC model introduces iterations (cycles)

  UP is an adaptive system development methodology

Object-Oriented Analysis and Design with the Unified Process   34
                      Summary (continued)
  UP life cycle includes four phases-inception,
   elaboration, construction, and transition
  UP phases decomposed into one ore more iterations
  Iterations involve work in nine UP disciplines
  CASE: automation tools simplify development tasks




Object-Oriented Analysis and Design with the Unified Process   35

				
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posted:7/12/2012
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