Reverse operation of extract (json4s)

Question

json4s allows user to convert a JsonAST object to a case class using extract.

import org.json4s._
import org.json4s.jackson.JsonMethods._

implicit val formats = DefaultFormats

case class Item(name: String, price: Double)
val json = parse("""{"name": "phone", "price": 1000.0}""") // JObject(List((name,JString(phone)), (price,JDouble(1000.0))))
val item = json.extract[Item] // Item(phone,1000.0)

However, to convert a case class into a JsonAST object, the only way I can think of is:

serialize a case class using write
deserialize a string using extract

Like below:

parse(write(item)) // JObject(List((name,JString(phone)), (price,JDouble(1000.0))))

Is there any better way for the conversion? Thank you!

Does this cover what you want? https://stackoverflow.com/questions/22992472/how-to-serialize-object-to-ast-using-json4s — Ethan, Sep 13 '18 at 17:35

yiksanchan · Accepted Answer · 2018-09-15T02:24:23.903

1

Extraction.decompose converts a case class object into a JsonAST.

Extraction.decompose(item) // JObject(List((name,JString(phone)), (price,JDouble(1000.0))))

edited Sep 15 '18 at 02:24

answered Sep 13 '18 at 18:19

yiksanchan

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Please add a supporting description to explain *why* this answers the question. – Steve Land Sep 14 '18 at 10:19

Reverse operation of extract (json4s)

1 Answers1