Play api json date reader and writer for extended mongo dates

gistfile1.scala

object MeetingMongo {
  val dateReader: Reads[Date] = new Reads[Date] {
    def reads(jsValue: JsValue): JsResult[Date] = {
      (jsValue \ "$date").validate[Long].map { l => new Date(l) }
    }
  }

  val dateWriter: Writes[Date] = new Writes[Date] {
    def writes(date: Date): JsValue = Json.obj("$date" -> JsNumber(date.getTime))
  }

  implicit val dateFormatter = Format(dateReader, dateWriter)  
  implicit val formatter = Json.format[Meeting]
  
}