Marine Biology Case Study

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Marine Biology Case Study

• http//web-cat.cs.vt.edu/CsEdWiki/JettWorkshop
• Stephen Edwards, Dwight Barnette, and Ed Fox
• Virginia Tech Dept. of Computer Science

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This case study provides many opportunities

• A larger example system students can learn from
• More interesting to look at, work with, and
  extend than simple text examples
• More of a real-world meaningful tie-in
• Ripe source for discussing tradeoffs (design,
  performance issues, readability, and more)
• Intended to model good coding, design, and
  documentation practice
• Context for covering design and testing

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The backstory for the MBCS

• A CS student, Pat, gets a summer job working for
  marine biologists
• Hired to enhance an existing program that
  simulates fish movement in a bounded environment
• Needs to understand existing program
• Designs, codes, and tests modifications
• Occasionally Pat turns to an experienced
  programmer, Jamie, for help
• The narrative is Pats report of this summer job

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The chapters in the narrative structure the
activities

• Chapter 1
• Experimenting with the existing program (running
  it)
• Informal testing
• Good as introduction or review of running
  programs, exploring multiple interacting objects
• Opportunities to practice logical reasoning and
  problem-solving skills without programming

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The chapters in the narrative structure the
activities

• Chapter 2
• A guided tour of the code by Jamie
• Good review of basic programming constructs
  (variables, methods, control structures, etc.)
• Public vs. private (some classes use protected as
  well)
• Exploration of fish movement
• Has arrays and ArrayList (can be covered out of
  order)

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The chapters in the narrative structure the
activities

• Chapter 3
• Modifying existing code to add new features
• Adding breeding and dying behaviors to fish
• Uses Random class for probabilistic combination
  of behaviors
• If you do Ch. 4 first, you can add features
  through subclassing instead of by directly
  modifying the code

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The chapters in the narrative structure the
activities

• Chapter 4
• Add two new kinds of fish
• Darters and slow fish move differently
• Inheritance
• Dynamic binding

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The chapters in the narrative structure the
activities

• Chapter 5 (AB only)
• Interfaces
• Alternative representations of the environment
• Bounded 2D array implementation
• Unbounded environment using ArrayList

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Resources on our web site

• See the APCS section at the bottom of the
  workshops main page
• Links to several MBCS resources on-line,
  including various versions of the case study for
  different IDEs
• Add your own if you know of other good resources!