喷雾JSON。如何从json获取对象列表

时间:2017-08-24 13:04:19

标签: json scala akka-http spray-json

我正在尝试使用akka-http-spray-json 10.0.9

我的模特:

case class Person(id: Long, name: String, age: Int)

我得到带有人员列表的json字符串jsonStr并尝试解析它:

implicit val personFormat: RootJsonFormat[Person] = jsonFormat3(Person)

val json = jsonStr.parseJson
val persons = json.convertTo[Seq[Person]]

错误:

  

字段'id'中预期的对象


我可能需要创建implicit object extends RootJsonFormat[List[Person]]并覆盖readwrite方法。

implicit object personsListFormat extends RootJsonFormat[List[Person]] {
    override def write(persons: List[Person]) = ???

    override def read(json: JsValue) = {
        // Maybe something like
        // json.map(_.convertTo[Person])
        // But there is no map or similar method :(
    }
}

P.S。对不起我的英语,这不是我的母语。

UPD
jsonStr:

[ {"id":6,"name":"Martin Ordersky","age":50}, {"id":8,"name":"Linus Torwalds","age":43}, {"id":9,"name":"James Gosling","age":45}, {"id":10,"name":"Bjarne Stroustrup","age":59} ]

1 个答案:

答案 0 :(得分:1)

我得到了完美预期的结果:

import spray.json._

object MyJsonProtocol extends DefaultJsonProtocol {
  implicit val personFormat: JsonFormat[Person] = jsonFormat3(Person)
}

import MyJsonProtocol._

val jsonStr = """[{"id":1,"name":"john","age":40}]"""
val json = jsonStr.parseJson
val persons = json.convertTo[List[Person]]
persons.foreach(println)