Iterative, Evolutionary, and Agile

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Chapter 2

• Iterative, Evolutionary, and Agile

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Unified Process

• A software development process describes an
  approach to building, deploying, and maintaining
  software.
• Unified Process, Rational Unified Process, Open
  Unified Process.
• Flexible and open.
• Other iterative methods Extreme Programming
  (XP), Scrum,

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Iterative and Evolutionary Development Fig. 2.1
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Iterative and Evolutionary Development

• Successive refinement and enlargement of a system
  through multiple iterations (mini-projects), with
  cyclic feedback and adaptation.
• Iterative and Incremental Development.
• Timeboxed iterations fixed length periods. No
  date slippage.

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Fig. 2.2
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The Failure-Prone Waterfall Process Fig. 2.3
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Fig. 2.4
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Agile Development

• The Agile Manifesto
• Individuals and interactions over processes and
  tools.
• Working software over comprehensive
  documentation.
• Customer collaboration over contract negotiation.
• Responding to change over following a plan.
• Examples
• Scrum a common project working-room and
  self-organizing teams, daily stand-up meeting
  with 4 special questions from each member.
• XP programming in pairs and test-driven
  development.

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Agile Modeling

• Main purpose is to support understanding and
  communication, not documentation.
• Model and apply UML for the smaller percentage of
  unusual, difficult, and trick design parts.
• Use the simplest tool.
• Model in pairs (or triads) on the whiteboard.
• Create models in parallel.
• Models are not final.
• Developers should do the OO design modeling for
  themselves, not for other coders.

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Fig. 2.5
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Agile UP

• Prefer a small set of UP activities and
  artifacts. Focus on early programming, not early
  documenting.
• Requirements and designs are not completed before
  implementation they evolve through a series of
  iterations based on feedback.
• Apply the UML with agile modeling practices.
• High level Phase Plan vs. detailed Iteration
  Plan.

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Fig. 2.6
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UP Phases

• Inception
• Approximate vision, business case, scope, vague
  estimates
• Elaboration
• Refined vision, iterative implementation of core
  architecture, resolution of high risks,
  identification of most requirements and scope,
  more realistic estimates.
• Construction
• Iterative implementation of the remaining lower
  risk and easier elements, and preparation for
  deployment.
• Transition
• Beta tests, deployment

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Fig. 2.7
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Fig. 2.8
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Fig. 2.9
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Reading Assignments

• Review
• Chapter 1
• Chapter 2
• Forward Reading
• Chapter 3
• Chapter 4
• Chapter 5
• Chapter 6 Use Case