void setQuantity(int q); int getQuantity()

   void setPrice(float p); float getPrice()

   void setTemperature(Temperature t)
   Temperature getTemperature()

   void setDataFile(File f); File getDataFile()
}

class ItemRules extends RuleSource {
   @Model
   void item(Item item) {
      def data = item.dataFile.text.trim()
      def (name, quantity, price, temp) = data.split(',')
      item.name = name