Skip to content
Sign inGet Started

OOPS · written course

Objects, and the code that gets easier to change

Writing code that stays easy to change as it grows.

Start reading32 pages · about 165 minutes

By the end of this course

Not four pillars to recite: four tools for the same problem, which is that programs get harder to change as they grow. By the end you can read a class hierarchy, say what a program prints, spot an encapsulation leak, and explain which SOLID principle a piece of bad code is breaking.

All 32 pages

  1. 1The function that ate a team5 min read
  2. 2Classes, objects and what static really means5 min read
  3. 3Bringing an object into existence5 min read
  4. 4Belonging to the class or to the object5 min read
  5. 5Deciding what the outside may touch5 min read
  6. 6Encapsulation, and the getter that leaks5 min read
  7. 7Abstraction: depending on what, not how5 min read
  8. 8Two ways to say what something must do5 min read
  9. 9Inheritance, and when it is the wrong tool5 min read
  10. 10Two words one letter apart5 min read
  11. 11Polymorphism: the same call, different code6 min read
  12. 12How the right method gets found5 min read
  13. 13Has a, rather than is a6 min read
  14. 14When something goes wrong5 min read
  15. 15Designing what failure looks like5 min read
  16. 16Fixing the function from page one6 min read
  17. 17Single responsibility, open closed, Liskov6 min read
  18. 18Interface segregation and dependency inversion5 min read
  19. 19Passing in what a class needs5 min read
  20. 20Types as parameters5 min read
  21. 21Choosing where to put things5 min read
  22. 22The same object, or an equal one5 min read
  23. 23How deep does the copy go5 min read
  24. 24Objects that never change5 min read
  25. 25What a variable actually holds5 min read
  26. 26Memory nobody has to free5 min read
  27. 27Four patterns worth knowing5 min read
  28. 28Testing behaviour, not structure5 min read
  29. 29Standing in for a real collaborator5 min read
  30. 30Ideas worth borrowing5 min read
  31. 31Breaking up the class that does everything6 min read
  32. 32When objects are the wrong answer5 min read

Then what

Reading is the first half. When you finish, the questions for this subject test whether it went in, and every wrong option tells you why it was wrong rather than just that it was.

See the questions for OOPS