A craftsman’s guide to designing clean architecture

In this talk, Software Craftsman Marcus Biel describes how to design a Clean Architecture

Transcript

1. Marcus Biel, Software Craftsman
   Moscow | 7. April 2018
   A craftsman’s guide to
   designing clean architecture
   

   View Slide

2. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   About me
   Clean Code Evangelist • Founder of Clean Code
   Academy • Public Speaker • Author • Java Influencer
   • JCP Member • Clean Code Coach • Java
   Consultant
   @MarcusBiel
   marcus@cleancodeacademy.com
   

   View Slide

3. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   Defining a Clean Architecture
   

   View Slide

4. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   Defining a Clean Architecture
   

   View Slide

5. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   Defining a Clean Architecture
   

   View Slide

6. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   Defining a Clean Architecture
   MODULES
   PACKAGES
   CLASSES
   METHODS
   

   View Slide

7. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   Defining a Clean Architecture
   Domain
   Infrastructure
   HTTPS
   REST
   SOAP
   

   View Slide

8. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   Foundation of a Clean Architecture
   ‣ Coupling and Cohesion
   ‣ Other Building Blocks
   

   View Slide

9. Copyright 2018 Marcus Biel
   https://cleancodeacademy.com
   Defining Coupling
   Tight Coupling Loose Coupling
   

   View Slide

10. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Defining Coupling
    Tight Coupling Loose Coupling
    

    View Slide

11. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Defining Coupling
    Tight Loose
    

    View Slide

12. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Coupling Strength
    ‣ Distance of the Components
    ‣ Type of Coupling
    ‣ Timing of Coupling
    

    View Slide

13. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Distance of the Components
    MODULES
    PACKAGES
    CLASSES
    METHODS
    

    View Slide

14. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Distance of the Components
    

    View Slide

15. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Distance of the Components
    

    View Slide

16. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Distance of the Components
    

    View Slide

17. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Distance of the Components
    

    View Slide

18. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Type of Coupling
    

    View Slide

19. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Timing of Coupling
    

    View Slide

20. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Defining Cohesion
    Low Cohesion High Cohesion
    

    View Slide

21. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Defining Cohesion
    Low Cohesion High Cohesion
    

    View Slide

22. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Low High
    Defining Cohesion
    

    View Slide

23. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Defining Cohesion
    GeneralUtils
    create(Customer)
    validate(Car)
    write(Report)
    

    View Slide

24. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Defining Cohesion
    CustomerService
    sellTo(Customer)
    invoice(Customer)
    help(Customer)
    

    View Slide

25. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    help(Customer)
    invoice(Customer)
    Defining Cohesion
    CustomerSales
    sellTo(Customer)
    CustomerAccounting
    CustomerService
    

    View Slide

26. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Cohesion Types
    ‣ Logical Cohesion
    ‣ Business Cohesion
    

    View Slide

27. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Cohesion Key Point
    High Cohesion requires in-depth knowledge
    of the domain.
    

    View Slide

28. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Foundation of a Clean Architecture
    ‣ Coupling and Cohesion
    ‣ Other Building Blocks
    

    View Slide

29. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Other Building Blocks
    ‣ Encapsulation
    ‣ Naming
    ‣ Size
    

    View Slide

30. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Encapsulation
    technically enforces of how the
    system should be used
    Getters and Setters violate
    encapsulation.
    Use package private more often!
    http://bit.ly/EvilGettersAndSetters
    

    View Slide

31. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Other Building Blocks
    ‣ Encapsulation
    ‣ Naming
    ‣ Size
    

    View Slide

32. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Clean Names Key Points
    Clean names drive high cohesion 

    (Customer, AccountNumber)
    Use service pattern judiciously
    Clean names are team work
    Rename on new insights
    

    View Slide

33. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Other Building Blocks
    ‣ Encapsulation
    ‣ Naming
    ‣ Size
    

    View Slide

34. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    Size Key Points
    MODULES
    PACKAGES
    CLASSES
    METHODS
    

    View Slide

35. Copyright 2018 Marcus Biel
    https://cleancodeacademy.com
    What is Clean Architecture?
    I would advise students to pay more attention to
    the fundamental ideas rather than the latest
    technology. The technology will be out-of-date
    before they graduate. Fundamental ideas never get
    out of date.
    — David L. Parnas
    “
    ”
    

    View Slide

36. Marcus Biel, Software Craftsman
    Moscow | 7. April 2018
    A craftsman’s guide to
    designing clean architecture
    

    View Slide