Play for Scala: replicate structure in Json of array within array

Question

I have in Scala an array array1 that contains, among other things, another array array2.

Now, I'm trying to replicate the structure in Json using Play. This is my attempt:

    var json = JsObject(Seq())
    array1.foreach(a1 => {
      json += "a1" -> JsNumber(a1.name) + 
      "a2" -> a1.array2.foreach {
        a2 => "a2" -> JsString(a2.name)
      }
    })

The error I'm getting is type mismatch; found : Unit required: play.api.libs.json.JsValue

How to fix this? thanks in advance.

Use map instead of foreach. foreach is for side-effect operations — Nikita
– Nikita, Commented Jul 10, 2016 at 11:43
Could you provide an example of how do your arrays look like? It would be easier to reproduce your error. — Paweł Jurczenko
– Paweł Jurczenko, Commented Jul 10, 2016 at 11:51

Bruce Lowe · Accepted Answer · 2016-07-10 13:26:39Z

1

You probably want is to use map instead of foreach in the loops.

It's a little unclear as to what json you want, but based on the description of your objects, I'd say this is probably what you are a looking for:

val json =  JsArray(array1.map { a1 =>
  JsObject(List(
    "a1" -> JsNumber(a1.name),
    "a2" -> JsArray(a1.array2.map {
      a2 => JsString(a2.name)
    })
  ))
})

edited Jul 10, 2016 at 13:26

answered Jul 10, 2016 at 12:07

Bruce Lowe

6,2231 gold badge40 silver badges47 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Play for Scala: replicate structure in Json of array within array

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related