What is "Entity" in DDD?

Transcript

1. What is “Entity” in DDD? k-kuwahara @kuwahara_jsri @clown0082 Mar 10,

   2020 Active Book Dialogue @Yumemi

2. const my_info = { Workplace: ‘Yumemi Inc’, Position1: ‘Servant Leader

   of FET’, Position2: ‘CEO(secondary)’, Community: ‘Riot.js, Ionic, DIST’, PokemonGO: ‘TL40’ } About me

3. npm/~kkeeth

4. github.com/riot

5. definition of “Entity”

6. embody Domain Model Domain Object definitin of “Entity”

7. embody Domain Model definitin of “Entity” Domain Object But, there

   are 2 objects. So, “Value Object”, “Entity”

8. What is the difference between “Value Object” and “Entity”?

9. the difference Value Object Entity diff attributes/variables identity property immutability

   valiability change exchange/substitution behavior

10. Value Object

11. Value Object Name: John Age: 32 Gender: Male Name: Emily

    Age: 27 Gender: Female

12. Value Object Name: John Age: 32 Gender: Male Name: John

    Age: 32 Gender: Male

13. Entity

14. Entity Name: John Age: 32 Gender: Male Name: Emily Age:

    27 Gender: Female

15. Entity Name: John Age: 32 Gender: Male Name: John Age:

    32 Gender: Male

16. How do “Entity” identify each other?

17. Entity ID: 12345 Name: John Age: 32 Gender: Male ID:

    98765 Name: John Age: 32 Gender: Male

18. Entity ID: 12345 Name: John Age: 32 Gender: Male ID:

    98765 Name: John Age: 32 Gender: Male identity identity ID: 12345 ID: 98765

19. Merits of “Entity”

20. merits of “Entity” Code is more documentable Make changes in

    our domain easier to communicate to your code

21. merits of “Entity”

22. embody merits of “Entity”

23. Let’s join DDD!!

24. None