Unable to generate a serializer for java.time.Month

[dkhalanskyjb]

The following code produces a compilation error:

@ExperimentalSerializationApi
@Serializer(forClass = java.time.Month::class)
object MonthSerializer: KSerializer<java.time.Month>

The error:

Object 'MonthSerializer' is not abstract and does not implement abstract member public abstract val descriptor: SerialDescriptor defined in kotlinx.serialization.KSerializer

[sandwwraith]

Not sure this is a bug though: external serialization of Java classes was never supported, nor we have any plans or design goals to support it. Java classes can't be serialized by kotlinx.serialization automatically.

[qwwdfsad]

Well, even if it's technically not possible to generate a serializer for Java enum, at least a clear actionable error message should be printed. E.g. like Serializer cannot be automatically generated for Java classes. with addition for enums EnumSerializer(JavaEnum.values()) can be used instead.

[dkhalanskyjb]

EnumSerializer seems to be an internal definition.