Agenda

• Introduction
  • Refactoring Opportunities: pre-done, boy-scout, pre-change, post-frustration, post-rush
  • Refactoring Stoppers: lack of time, fear, long branches, focus
  • Teamwork: code review, intentional-commits, pair programming
  • ⭐Baby-steps refactoring: how to split large changes in tiny steps
• Expressive Code
  • Good names: explanatory variables, methods, and constants
  • Function signature: numbers of parameters, booleans (and default parameters)
  • Function depth and guard clauses
  • The 3 rules of a clean switch
  • Finding seams to break code in comments, empty lines, indentations
  • Exceptions Best Practices
• Clean OOP Code
  • Extracting Value Objects; Lack of abstractions
  • Encapsulation: push behavior next to State
  • Enforcing domain constraints; Micro-types
• Clean FP Code
  • CQS Principle, Pure Functions & Immutable Objects; tradeoffs
  • Replacing loops (for) with FP pipelines (.map, .filter, ..)
  • FP patterns and anti-patterns: side-effects, Try, Tuple4, stream wreck
  • [java] Optional<> best practices; null-safe data model
• Refactoring Moves with IDE
  • Extract & Inline of variables, methods, parameters, constants and interfaces
  • Change Method Signature, Introduce Parameter Object, Move methods in data structures
• Code Smells – the most damaging micro-design issues of today & ways to fix
• Larger Refactoring Exercises (2-4 hours):
  • Victor on 1-2 snippets of Production Code from the audience, and/or
  • Participants on a Refactoring Kata in Pairing or Mobbing
• Any Other Debates, guided by the audience questions

Follow-up Refactoring Exercises (optional, after the workshop):

– Yatzy (practice FP): https://github.com/emilybache/Yatzy-Refactoring-Kata

– Gilded Rose (practice OOP): https://github.com/emilybache/GildedRose-Refactoring-Kata

– Supermarket (practice modeling): https://github.com/victorrentea/kata-supermarket-java