Mapping a data class to another data class typically found in the apps which follows clean architecture (domain, etc.)

library.kt

/**
 * If there is two same classes like below one maybe domain & other may be entity
 * Following method might help to map such instance to other classes.
 *
 * This is done completely through reflection by matching parameters name.
 *
 * [convertType] This can be used to transform intermediate values if their types are different in other.
 */
inline fun <reified F : Any, reified T : Any> mapToClass(from: F, convertType: (String, Any?) -> Any? = { _,v -> v }): T {
    val args = HashMap<KParameter, Any?>()
    val params: List<KParameter> = T::class.constructors.first().parameters
    F::class.memberProperties.forEach { prop: KProperty1<out F, Any?> ->
        if (prop.visibility == KVisibility.PUBLIC) {
            val kParam: KParameter = params.first { it.name == prop.name }
            val value: Any? = prop.getter.call(from)
            args[kParam] = convertType.invoke(kParam.name!!, value)
        }
    }
    return T::class.constructors.first().callBy(args)
}

Example usage

data class Setting(
   val isSettings1: Boolean,
   val computeMathExp: List<String>,
   val episodeNum: Int
)

@Entity // Example Room
data class SettingDb(
   val isSettings1: Boolean,
   val computeMathExp: String,
   val episodeNum: Int
)

val setting = Setting(...)
val settingsDb: SettingDb = mapToClass(setting) { p, v ->
   // Use this callback to transform data from one type to another eg: computeMathExp
   if (p == Setting::computeMathExp.name) {
       return@call (v as List<String>).joinToString()
   }
   return@call v                                               
}