Johnson and Foote's heuristics

See [Designing Reusable Classes]

Johnson and Foote 1988

• • Recursion introduction
  • Eliminate case analysis
  • Reduce the number of arguments
  • Reduce the size of methods
  • Class hierarchies should be deep and narrow
  • The top of the class hierarchy should be abstract
  • Minimize accesses to variables
  • Subclasses should be specializations
  • Split large classes
  • Factor implementation differences into subcomponents
  • Separate methods that do not communicate
  • Send messages to components instead of to self
  • Reduce implicit parameter passing