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What is "Entity" in DDD?
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kkeeth
March 10, 2020
Technology
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What is "Entity" in DDD?
kkeeth
March 10, 2020
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Transcript
What is “Entity” in DDD? k-kuwahara @kuwahara_jsri @clown0082 Mar 10,
2020 Active Book Dialogue @Yumemi
const my_info = { Workplace: ‘Yumemi Inc’, Position1: ‘Servant Leader
of FET’, Position2: ‘CEO(secondary)’, Community: ‘Riot.js, Ionic, DIST’, PokemonGO: ‘TL40’ } About me
npm/~kkeeth
github.com/riot
definition of “Entity”
embody Domain Model Domain Object definitin of “Entity”
embody Domain Model definitin of “Entity” Domain Object But, there
are 2 objects. So, “Value Object”, “Entity”
What is the difference between “Value Object” and “Entity”?
the difference Value Object Entity diff attributes/variables identity property immutability
valiability change exchange/substitution behavior
Value Object
Value Object Name: John Age: 32 Gender: Male Name: Emily
Age: 27 Gender: Female
Value Object Name: John Age: 32 Gender: Male Name: John
Age: 32 Gender: Male
Entity
Entity Name: John Age: 32 Gender: Male Name: Emily Age:
27 Gender: Female
Entity Name: John Age: 32 Gender: Male Name: John Age:
32 Gender: Male
How do “Entity” identify each other?
Entity ID: 12345 Name: John Age: 32 Gender: Male ID:
98765 Name: John Age: 32 Gender: Male
Entity ID: 12345 Name: John Age: 32 Gender: Male ID:
98765 Name: John Age: 32 Gender: Male identity identity ID: 12345 ID: 98765
Merits of “Entity”
merits of “Entity” Code is more documentable Make changes in
our domain easier to communicate to your code
merits of “Entity”
embody merits of “Entity”
Let’s join DDD!!
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