The value-object tag has no usage guidance.
8
votes
2answers
234 views
Should well-known business ID of an entity be represented with a dedicated type in DDD/OOP?
In practical terms it means using an custom (immutable) class over a string or some other primitive type.
Examples:
Publishing: International Standard Book Number.
Finance: International Securities ...
0
votes
1answer
25 views
VO to Entity Conversion
In our application we have multiple layers.
UI -> This can be JSP/ JSON result of the API
Controllers -> as in MVC
Services -> perform single business operation per service
DAOs -> Data Access ...
0
votes
2answers
114 views
Getters with data conversion in Java VOs
I am working on a standard Spring application where DAO layer returns entities to service layer and service layer returns VOs to other services and controllers.
In a certain scenario, we have a VO ...
0
votes
1answer
69 views
domain driven design value object behavior
I recently finished Steve Smith and Julie Lerman's excellent Pluralsight course on Domain Driven Design, and I'm applying the training to a project. I have what I think is a good candidate for a value ...
0
votes
3answers
530 views
Overriding equals() method in Java
Short question: Why does Java allow overriding equals(), why is it not final?
I am reading Effective Java 2nd edition by Joshua Bloch.
I am a bit baffled by the conclusion that
There is no way to ...
3
votes
2answers
282 views
How should blank/empty value objects be instantiated/structured?
I was wondering... what is considered the best practice to instantiate blank value objects? (in Java)
E.g. Assume we have some value object class Foo, that could be blank.
Would creating methods ...
6
votes
3answers
444 views
In domain driven design, how do I convert a database table with a primary key into a Value Object?
Lets suppose there's a database schema defined like this:
Person.mail_address_key ----- Address.address_key
Person.billing_address_key ----- Address.address_key
A Person has a mailing address and a ...
1
vote
2answers
108 views
DDD - If an object is saved as a whole to the database, is it per definition an entity, or is it still possible that it is a value object?
I'm learning about Domain Driven Design and struggling with the question if a particular object should be handled as entity or value object.
All possible surname prefixes are kept in a database ...
4
votes
1answer
320 views
Use a custom value object or a Guid as an entity identifier in a distributed system?
tl;dr
I've been told that in domain-driven design, an identifier for an entity could be a custom value object, i.e. something other than Guid, string, int, etc. Can this really be advisable in a ...
3
votes
2answers
1k views
DDD and the persistence of value objects; must we denormalize?
I've been reading up a lot on Domain-Driven Development, and I came to the question of how to preserve lack of distinct identity with value objects (VOs). While in the DDD world, this is a requirement ...
2
votes
1answer
71 views
A good name for ValueObject that contains database update/create column values [closed]
We all know these fields, database admins so like to add:
UserCreated & DateCreated
UserUpdated & DateUpdated
They need to be displayed in the UI so I want to put them in some ValueObject ...
0
votes
1answer
197 views
Shouldn't Location be a Value Object?
Eric Evan's DDD book, Cargo Shipping Example, pg. 168:
Location
Two places with the same name are not the same. Latitude and longitude
could provide a unique key, but probably not a very ...
6
votes
1answer
1k views
Unique Value Object vs Entity
Trying to convert some entities into value objects I am stuck in a case where what seems a value object must be unique within an aggregate.
Suppose we have a Movie entity which makes the root of an ...
