为Json4s编写自定义序列化器

问题描述：

由于Json4s仅在键是字符串时才带有Map序列化，所以我试图用Java枚举作为键为特定Map编写自定义序列化程序.

Since Json4s come with Map serialization only when the key is a String, I am trying to write my custom serializers for a specific Map with Java enums as key.

class HistoricalRecordCustomSerializer extends CustomSerializer[Map[QuotedData,Double]](
  format => (
    {
      case JArray(items) =>
        items.map{
                   case JObject(JField(name,JDouble(value))::Nil) => (QuotedData.valueOf(name),value)

                 }.toMap


    },
    {
      case x: Map[QuotedData,Double] =>
        JArray(
          x.map(entry =>
                  JObject(
                    List(
                      JField(entry._1.toString,JDouble(entry._2))
                    )
                  )
        ).toList
        )
} ) )

首先，此实现显然在序列化的情况下不起作用，因为已删除了x: Map[QuotedData,Double].此外，我无法使用它来获取json4s. 编写此自定义序列化程序的正确方法是什么?

First of all, this implementation clearly does not work in case of serializing, because x: Map[QuotedData,Double] is erased. Additionally, I can't manage to get json4s using it. What is the correct way to write this custom serializer?

答

Json4s在此阶段仅了解字符串键，因此您要实现的目标不适用于地图.

Json4s only knows about string keys at this stage, so what you're trying to achieve won't work with a map.

为Json4s编写自定义序列化器

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