Data class where i need to set values for different fields at different times
Use Data Class which automatically generates field accessors, hashCode(), equals(), toString() and other methods. Read this for a quick introduction. 

data class ABCDRequest (
    @JsonProperty("name")
    private var name: String? = null,
    @JsonProperty("question")
    private var question: String? = null,
    @JsonProperty("ans")
    private var ans: String? = null
)


For the official documentation on Data Class, head over to this link.