Transform Future into class or Map

Question

I have a class ClassName(id:String, etc:String, long:Long)

And a function that returns that object from the DB as Future[Option[ClassName]]

I want to get transform that result (the Future[Option]) as, either a class with it's values, or a Map[String, AnyRef]

Does anyone knows how to handle this transform? I haven't been finding any answers on the internet

Related? http://stackoverflow.com/questions/17713642/accessing-value-returned-by-scala-futures — Dan W, Apr 06 '17 at 18:36
@Tyler I want to extract a value from a database using Akka HTTP so I give it to the user. It's a project based on this one: https://github.com/ArchDev/akka-http-rest — Javier Bullrich, Apr 06 '17 at 19:02
@JavierBullrich can you be more specific as to what "give it to the user" means? Are you responding to an HTTP request, displaying to a desktop giu or something else? Also, what exactly is the thing that you are "giving" to the user? — puhlen, Apr 07 '17 at 14:41

Javier Bullrich · Accepted Answer · 2017-04-07T15:13:44.167

-2

I manage to create this function which returns me the class that is inside the future.

It's not generic, so it won't be very elegant, but it does the job

def convertToClass(futureEntity: Future[Option[ClassName]]): ClassName = { var newClass: ClassName = null futureEntity onComplete { case Success(value) => value match { case Some(s) => newClass = s case None => null } case Failure(e) => e.printStackTrace null } newClass }

EDIT: That method wasn't working. This one does:

def convertToMyClass(futureEntity: Future[Option[ClassName]]): ClassName = {
    var myClass: ClassName = null
    Await.ready(futureEntity andThen {
      case Success(value) =>
        value match {
          case Some(s) => myClass = s
          case None => null
        }
      case Failure(e) => e.printStackTrace
        null
    }, Duration.Inf)
    myClass
  }

edited Apr 07 '17 at 15:13

answered Apr 07 '17 at 13:26

Javier Bullrich

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This doesn't work at all, you will just get `null` as your result. – puhlen Apr 07 '17 at 14:37
@puhlen yes, but I can parse a null. I know that if it's null, the value doesn't exist in the db. – Javier Bullrich Apr 07 '17 at 14:53
no, this will return null even if the value exists in the database. If you want to block and extract the value you can use `Await.result` but it's better to do it asynchronously and stay in the future. – puhlen Apr 07 '17 at 14:58
@puhlen I fixed and tested. You were right. I edited my answer. – Javier Bullrich Apr 07 '17 at 15:14

Transform Future into class or Map

1 Answers1