Hey, I need a little help with generics. I've trie...

# serialization

[Gergely Kőrössy]

Hey, I need a little help with generics. I've tried searching for a solution but I couldn't find any. I want to encode to / decode from JSON.
I have the following class:

data class Nice<T: @Serializable Any>(
    @SerialName("id") val id: String,
    @SerialName("type") val type: String,
    // ... about 5 more parameters ...
    @SerialName("value") val value: T,
)

Based on the type parameter, the value could be a couple of serializable things: list of a data class(id,name) items, a single data class(id,name) item, or a boolean value.
• If I don't set a custom serializer with @Serializable(with = ...), the encoding to JSON works, but decoding from JSON runs into Star projections in type arguments are not allowed, but had null error (trying to decode it as Nice<*>.
• If I set a custom serializer by implementing JsonContentPolymorphicSerializer I get Class 'Nice' is not registered for polymorphic serialization in the scope of 'Nice'. even for encoding.
Is there any way to tell the deserializer that if the type value is something, decode value as either a list / single item / boolean without implementing a full on KSerializer? There are quite a few parameters in the class and would be nice not writing encode / decode statements for each one of them.

[Adam S]

Does this answer help? https://stackoverflow.com/questions/74489345/decoding-json-to-a-class-based-on-the-value-of-another-json-key/74489912#74489912

[Gergely Kőrössy]

Well, the thing is that in this example the Interaction<T> would be also in another class that would be encoded / decoded.
If I specify @Serializable(with = InteractionJsonSerializer::class) on the Interaction class, even encoding the Interaction results in Class 'Interaction' is not registered for polymorphic serialization in the scope of 'Interaction'. error

[Gergely Kőrössy]

So add this to the equation:

@Serializable
data class InteractionParent(
    val interaction: List<Interaction<*>>
)

[ephemient]

https://pl.kotl.in/oCuoI2LNg