Non-nullable ID with spring-data-mongodb in Kotlin

Question

Is there any chance to make the @Id property non-nullable for Mongo-related entities in Kotlin?

Referring to this post there seems to be a solution for SQL by setting the ID initially to 0. However, that seems like a hack, and seems to work only when using sequence generators.

My original intent is obviously to avoid nullable IDs like I have right now:

@Document class MyEntity( @Id var id: String? = null )

What I'd prefer if possible:

@Document class MyEntity( @Id val id: String )

Hett · Answer 1 · 2021-12-31T19:58:49.077

0

You can use lateinit, but this may lead to a runtime error:

@Document
class File : Serializable {
    @Id
    lateinit var id: ObjectId
}

edited Dec 31 '21 at 19:58

answered Dec 06 '21 at 10:17

Hett

3,484
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score -3 · Answer 2 · answered Oct 07 '18 at 00:30

-3

@Document(collection = COLLECTION_MY_ENTITY)
data class MyEntity @PersistenceConstructor constructor (
        @Id val id: String,
        @Field(FIELD_NAME) someField: String
)

answered Oct 07 '18 at 00:30

denis.zhdanov

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Could you please elaborate? How does this help me when I construct `MyEntity` by myself? – Jan B. Oct 07 '18 at 16:48
You shouldn't construct `MyEntity` by yourself. Store it through, say, `MongoTemplate` and use object representation when you load it from mongo – denis.zhdanov Oct 19 '18 at 23:44

Non-nullable ID with spring-data-mongodb in Kotlin

2 Answers2