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jsonscalajson4s

Try to convert json4s values into integers

I have random JSON strings that contain string values when they are really numbers but I have no way to know what fields they might be when coming into my system.

For example: 

{
   "some_key":"1234",
   "another_key":{
      "sub_key":"4243",
      "a_string":"this is a valid string and should not be converted"
   }
}

Does any one know of a simple way to try to convert json values into integers using json4s?

Solution

  • Figured it out. This piece of code does just what I need:

    private def convertNumbers(json: JValue) =
  json.transformField {
    case JField(k, v) ⇒ k → (v match {
      case s: JString ⇒ Try(JInt(s.s.toInt)).getOrElse(s)
      case o          ⇒ o
    })
  }