は、私は単に私の場合クラスのJSON形式を作成しようとしています暗黙のJSON形式の

Question

を証拠パラメータの暗黙の値を見つけることができませんでした：

object ApplicationProtocol extends DefaultJsonProtocol { 

    lazy implicit val ImageRequestFormat = jsonFormat(ImageRequest, "inputs") 
    lazy implicit val ImageObjectFormat = jsonFormat(ImageObject, "data") 
    lazy implicit val DataFormat = jsonFormat(Data, "image") 
    lazy implicit val ImageFormat = jsonFormat(Image, "url") 
    } 

：

case class ImageRequest (inputs: Array[ImageObject]) 

case class ImageObject(data: Data) 

case class Data(image: Image) 

case class Image(url: String) 

、ここでは、暗黙の形式ですエラーが表示されます：

> could not find implicit value for evidence parameter of type 
> connectors.ClarifaiConnector.ApplicationProtocol.JF[Array[model.ImageObject]] 
> [error]  lazy implicit val ImageRequestFormat = 
> jsonFormat(ImageRequest, "inputs") [error]        
>^[error] 
> /Users/MacZ/Dropbox/Work/Development/JobOffer/ImageProject/src/main/scala/connectors/clarifaiConnector.scala:27:53: 
> could not find implicit value for evidence parameter of type 
> connectors.ClarifaiConnector.ApplicationProtocol.JF[model.Data] 
> [error]  lazy implicit val ImageObjectFormat = 
> jsonFormat(ImageObject, "data") [error]        
>^[error] 
> /Users/MacZ/Dropbox/Work/Development/JobOffer/ImageProject/src/main/scala/connectors/clarifaiConnector.scala:28:46: 
> could not find implicit value for evidence parameter of type 
> connectors.ClarifaiConnector.ApplicationProtocol.JF[model.Image] 
> [error]  lazy implicit val DataFormat = jsonFormat(Data, "image") 
> [error]           ^

すべてがインポートされ、有効範囲内に表示されます

Answer 1

変更暗黙の順序：

object ApplicationProtocol extends DefaultJsonProtocol { 
    implicit val ImageFormat = jsonFormat(Image, "url") 
    implicit val DataFormat = jsonFormat(Data, "image") 
    implicit val ImageObjectFormat = jsonFormat(ImageObject, "data") 
    implicit val ImageRequestFormat = jsonFormat(ImageRequest, "inputs") 
} 

の作業例： https://scastie.scala-lang.org/Bh6ugVwVSTyOun5PG3I1lQ