为什么我会得到；应用程序不接受参数“；在Play framework 2.3中使用JSON读取？

我想在Play framework 2.3x中为几个Scala模型类编写JSON验证。我使用JSON读取来按照说明（）完成这项工作。但我得到了“应用程序不接受参数”错误，我不知道如何解决这个问题

这是我的密码

package models

import play.api.libs.json._
import play.api.libs.json.Reads._
import play.api.libs.functional.syntax._
import reactivemongo.bson.BSONObjectID
import java.util.Date

case class ArtifactModel(
                          _id: BSONObjectID,
                          name: String,
                          createdAt: Date,
                          updatedAt: Date,
                          attributes: List[AttributeModel],
                          stateModels: List[StateModel])

case class AttributeModel(
                           name: String,
                           comment: String)

case class StateModel(
                       name: String,
                       comment: String)

object ArtifactModel {
  implicit val artifactModelReads: Reads[ArtifactModel] = (
      (__ \ "_id").readNullable[String] ~
      (__ \ "name").read[String] ~
      (__ \ "createdAt").readNullable[Long] ~
      (__ \ "updatedAt").readNullable[Long] ~
      (__ \ "attributes").read[List[AttributeModel]] ~
      (__ \ "stateModels").read[List[StateModel]]
    )(ArtifactModel) // here is the error: "Application does not take parameters"


  implicit val attributeModelReads: Reads[AttributeModel] = (
      (__ \ "name").read[String] ~
      (__ \ "comment").read[String]
    )(AttributeModel)

  implicit val stateModelReads: Reads[StateModel] = (
      (__ \ "name").read[String] ~
      (__ \ "comment").read[String]
    )(StateModel)
}

---

你能帮我吗？对于Scala/Play中JSON验证的任何解决方案或建议，我们将不胜感激

Reads对象的类型与apply方法的类型不同。例如，

readNullable[String]

results

Option[String]

，而不是

String

。对于

BSONObjectId

和

日期

也一样。这可以编译，但您可能需要使用一些映射：

  implicit val artifactModelReads: Reads[ArtifactModel] = (
(__ \ "_id").read[BSONObjectID] ~
  (__ \ "name").read[String] ~
  (__ \ "createdAt").read[Date] ~
  (__ \ "updatedAt").read[Date] ~
  (__ \ "attributes").read[List[AttributeModel]] ~
  (__ \ "stateModels").read[List[StateModel]]
)(ArtifactModel.apply _)

您可以在读取后，像这样（

CONVERT\u TO\u DATE

是虚构的）：

---

我已经试过了，但对我不起作用。错误是一样的。我很困惑。

  implicit val artifactModelReads: Reads[ArtifactModel] = (
(__ \ "_id").read[BSONObjectID] ~
  (__ \ "name").read[String] ~
  (__ \ "createdAt").read[String].map( s=>CONVERT_TO_DATE(s) ) ~
  (__ \ "updatedAt").read[Date] ~
  (__ \ "attributes").read[List[AttributeModel]] ~
  (__ \ "stateModels").read[List[StateModel]]
)(ArtifactModel.apply _)