Object-Oriented Design

Identifying Objects (and Classes)

• Identify the nouns (objects) in the problem description.
• Identify more objects in your developing problem solution. (Design is incremental and iterative!   --   Grady Booch)
• From these objects, determine what new types (classes) you need.
  Example: BlackJack Program
  • cards
  • a deck
  • a dealer
  • player(s)

  Sample Design Questions:

  • Do different cards represent different types? Or are suit and rank attributes of a single card type?
  • Are the dealer and player instances of the same class? I.e., objects of the same type?
  • Should there be a separate Hand class?