Why I parse json into a Java List, but not a Scala List?
<p>I am attempting to parse a json object that contains a list. I am able to parse the list if the field is backed by a Java List, but it fails if the field is backed by a Scala list. What is the difference between parsing into a Scala List vs a Java List, and what do I have to change to be able to parse this into a Scala List?</p>

<pre><code>object JsonParsingExample extends App {
  val objectMapper = new ObjectMapper()

  // This line succeeds. 
  objectMapper.readValue("""{"list": ["a","b"]}""", classOf[JavaList])

  // This line fails.
  objectMapper.readValue("""{"list": ["a","b"]}""", classOf[ScalaList])
}

case class JavaList() {
  @JsonProperty(value = "list")
  var myList: java.util.ArrayList[String] = null
}

case class ScalaList() {
  @JsonProperty(value = "list")
  var myList: List[String] = null
}
</code></pre>

<p>The error message I receive is:</p>

<blockquote>
  <p>com.fasterxml.jackson.databind.JsonMappingException: Can not construct instance of scala.collection.immutable.List, problem: abstract types either need to be mapped to concrete types, have custom deserializer, or be instantiated with additional type information</p>
</blockquote>