Scala保留字作为带有Json.writes [A]的JSON字段名称(与@SerializedName等效的播放方式) [英] Scala reserved word as JSON field name with Json.writes[A] (Play equivalent for @SerializedName)

问题描述

我正在使用Play 2.4.3&制作JSON. Scala以以下方式提供由Json.writes创建的隐式Writes[DeviceJson].

I'm producing JSON with Play 2.4.3 & Scala in the following fashion, providing an implicit Writes[DeviceJson] created with Json.writes.

import play.api.libs.json.Json

case class DeviceJson(name: String, serial: Long, type: String)

object DeviceJson {
  implicit val writes = Json.writes[DeviceJson]
}

当然，以上内容无法编译，因为我试图在案例类中使用保留字type作为字段名称.

Of course, the above doesn't compile as I'm trying ot use the reserved word type as field name in the case class.

在这种情况下，最简单的输出JSON字段名称(例如不能用作Scala字段名称的type或match)的方法是什么?

In this scenario, what is the simplest way to output JSON field names such as type or match that I can't use as Scala field names?

例如，对于Java和Gson，使用自定义JSON字段名称(与代码中的字段名称不同)对于

With Java and Gson, for example, using a custom JSON field name (different from the field name in code) would be trivial with @SerializedName annotation. Similarly in Jackson with @JsonProperty.

我知道我可以通过滚动自己的Writes实现来做到这一点:

I know I can do this by rolling my own Writes implementation:

case class DeviceJson(name: String, serial: Long, deviceType: String)

object DeviceJson {
  implicit val writes = new Writes[DeviceJson] {
    def writes(json: DeviceJson) = {
      Json.obj(
        "name" -> json.name,
        "serial" -> json.serial,
        "type" -> json.deviceType
      )
    }
  }
}

但这是笨拙且重复的，特别是在类具有很多字段的情况下.有没有更简单的方法?

But this is clumsy and repetitive, especially if the class has a lot of fields. Is there a simpler way?

推荐答案

在您的案例类中，可以将反引号用作字段名称:

In your case class, you can use backtick for field name:

case class DeviceJson(name: String, serial: Long, `type`: String)

有了这个，您的Writes应该可以工作

With this, your Writes should work

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