ObjectMapper that deserializes JSON to mutable Maps and Seqs while also maintaining order

jackson-scala-module-mutableMap.scala

  object ATR extends AbstractTypeResolver {
    override def findTypeMapping(config: DeserializationConfig, javaType: JavaType) = {
      val result = Some(javaType) collect {
        case mapLikeType: MapLikeType =>
          if (javaType.getRawClass.equals(classOf[collection.Map[_, _]])) {
            TypeFactory.defaultInstance().constructSpecializedType(javaType, classOf[mutable.LinkedHashMap[_, _]])
          } else null
        case colType: CollectionLikeType =>
          if (javaType.getRawClass.equals(classOf[collection.Seq[_]])) {
            TypeFactory.defaultInstance().constructSpecializedType(javaType, classOf[mutable.LinearSeq[_]])
          } else null
      }
      result.orNull
    }
  }

  object AtrModule extends JacksonModule {
    this += (_ addAbstractTypeResolver ATR)
  }

  val mapper = new ObjectMapper() with ScalaObjectMapper
  mapper.registerModule(DefaultScalaModule)
  mapper.registerModule(AtrModule)