Serializer for squants.Quantity

Serializer.scala

object Serialization {
  object UnitSerialization {
    val unitForSymbol = Map(
      "millisecond" -> Milliseconds,
      "celsius" -> Celsius,
      "kelvin" -> Kelvin,
      "meter" -> Meters,
      "nanometer" -> Nanometers,
      "second" -> Seconds,
      "minute" -> Minutes,
      "hour" -> Hours
    )
    val symbolForUnit: Map[squants.UnitOfMeasure[_],String] =
      unitForSymbol map { case (x,y) => (y,x) } toMap
  }

  class QuantitySerializer extends Serializer[squants.Quantity[_]] {
    private val QuantityClass = classOf[squants.Quantity[_]]

    import UnitSerialization.{unitForSymbol, symbolForUnit}

    case class QVal(val unit: String, val value: Double)

    def deserialize(implicit format: Formats) = {
      case (TypeInfo(k, _), json) if QuantityClass.isAssignableFrom(k) =>
        val q = json.extract[QVal]
        unitForSymbol(q.unit)(q.value)
    }

    def serialize(implicit format: Formats) = {
      case q: squants.Quantity[_] =>
        JObject(List(
          "unit" -> JString(symbolForUnit(q.valueUnit)),
          "value" -> JDouble(q.value)
        ))
    }
  }
}