decodeNotNullMark

abstract fun decodeNotNullMark(): Boolean

Returns true if the current value in decoder is not null, false otherwise. This method is usually used to decode potentially nullable data:

// Could be String? deserialize() method
public fun deserialize(decoder: Decoder): String? {
if (decoder.decodeNotNullMark()) {
return decoder.decodeString()
} else {
return decoder.decodeNull()
}
}