It is possible to map static properties after selecting data from DB? For example if I want that result of some field will be always ENUM_VALUE. I will add an example to make myself more clear.

Target dto I want to fill via JOOQ

internal data class MytargetClass(val property: Int, val static_value: MyEnum)

Since static_value is val and its not optional, I need to initialize that property while creating object. So way to create object only with property and map static_value afterwards is not possible.

This is a solution that works, I add my enum value as string via val method, but this approach is not really something that I would want.

// Repository file, other fields and method omitted for simplicity        
        jooq
        .select(
            t.property.`as`("property"),
            DSL.`val`(Enum.MY_VALUE.name).`as`("static_value"),
        )
        // from and where clause omitted for simplicity
        .fetchInto(MytargetClass::class.java)

But I would like to ask if there is way how to do something like

// Repository file, other fields and method omitted for simplicity   
    jooq
    .select(
        t.property.`as`("property"),
    )
    // from and where clause omitted for simplicity
    .fetchInto(MytargetClass::class.java, (data) -> { data.static_value = Enum.MY_VALUE // possible more transformation of object inside this lambda })

So I dont have to select these properties statically via SQL and therefore I can bypass problems with ENUM dialects and other issues linked to this approach.

CodePudding user response：

Using DefaultRecordMapper

Just use a custom RecordMapper via ResultQuery.fetch(RecordMapper) and call apply on a mapped value

.fetch {
    it.into(MytargetClass::class.java).apply { 
        static_value = Enum.MY_VALUE
    }
}

Using any other RecordMapper

The above just assumes you want to continue using the DefaultRecordMapper, which is reflection based. But you don't have to. You can do anything you want with it:

.fetch {
    MytargetClass(it[t.property], Enum.MY_VALUE)
}