Clean code chapter 6 is explained in ZS Technical session.

1. Objects & Data Structure
Md. MaksudAlamChowdhury

3. ObjectVs Data

4. ObjectVs Data

5. Data Structure
 Exposes data
 Usually No behavior
 Referred as POJO or POPO in java and python respectively
 Can have private fields with public accessors
 Can have navigational methods ( ORM, Active Records )
 Should not have business logic

6. Object
 Encapsulates
 Hides data structures behind Abstraction
 Expose functions on that data

8. ProsAnd Cons

9. ProceduralCode using
Data Structure

11. OO Code using
Polymorphism

13. Pros and Cons
ProceduralCode
 easy to add new functions
without changing the existing
data structures
 hard to add new data
structures because all the
functions must change.
OOCode
 easy to add new classes
without changing existing
functions.
 hard to add new functions
because all the classes must
change.

16. Hybrids
 Combining Data Structure & Object
 Worst of both worlds
 Dependencies on attributes
 Difficult to add function and class
 Difficult to refactor

18. How depth can we go ?
 Known as Law of Demeter
 A module should hide objects it manipulates
 A method ( f ) of class ( C ) can call:
→ method of ( C )
→ method of an object held as instance variable in ( C )
→ method of an object passed as argument in ( f )
→ method of an object created by ( f )

19. Example

20. References
 Clean Code: A Handbook of Agile Software Craftsmanship
by Robert C. Martin
 The Clean Coder: A Code of Conduct for Professional
Programmers by Robert C. Martin

21. Questions