Scala: convert map to case class

Question

Let\'s say I have this example case class

case class Test(key1: Int, key2: String, key3: String)

And I have a map

myMap = M         


        

Answer 1

I don't love this code, but I suppose this is possible if you can get the map values into a tuple and then use the tupled constructor for your case class. That would look something like this:

val myMap = Map("k1" -> 1, "k2" -> "val2", "k3" -> "val3")    
val params = Some(myMap.map(_._2).toList).flatMap{
  case List(a:Int,b:String,c:String) => Some((a,b,c))
  case other => None
}    
val myCaseClass = params.map(Test.tupled(_))
println(myCaseClass)

You have to be careful to make sure the list of values is exactly 3 elements and that they are the correct types. If not, you end up with a None instead. Like I said, not great, but it shows that it is possible.