Refactoring

Refactoring

1. Small independent changes with the goal of improving

2. Rename

3. Collapse Hierarchy

4. Extract Method

5. Consolidate Conditional

   • Could write a method to evaluate larger conditionals

6. Decompose Conditionals

7. Extract Class

8. Important in industry where quality is important

   • Test Driven Development
     • Dynamic Verification(testing)
       • Performing levels of tests on the system to make sure it responds correctly
     • Static Verification
       • Examining code without executing it
     • Inspections/Reviews
       • Human intensive and often group-based review of the code
     • Formal Verification
       • Mathematical proof to ensure the code is 100% correct, can be very expensive
     • Writing the tests before the classes
     • Make it fail(TDD), make it work, make it better(refactor)

9. Should not refactor if code is broken

10. Code Smells

    • An indication that a deeper problem exists in the code
    • Technical debt - the amount of work created by trying to save time up front
    • Helps us identify problems
    • Bloaters
      • Classes that become too large
    • OO Abusers
      • Long switch statements instead of a method
    • Change Preventers
      • Shotgun surgery: having to make many small changes every time we make changes
      • Divergent change: making too many changes in one class when making changes
    • Dispensables
    • Feature Envy