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jsonscalajson4s

Json4s date to unixtimestamp

How to create wrapper for Json4s? Default json4s formater date converted all to SimpleDateFormat. I want convert all date field to unixtime format.

Solution

  • You should be able to implement your own Formats. Here is a simplified example, which is based on the SerializationExamples.

    EDIT: updated example

    import java.util.Date
import org.json4s._
import org.json4s.jackson.Serialization

object Main extends App {

  implicit val formats = new DefaultFormats {
    override val dateFormat: DateFormat = new DateFormat {
      override def parse(s: String): Option[Date] = Some(new Date(s.toLong * 1000))
      override def format(d: Date): String = (d.getTime/1000).toString
    }
  }

  case class Lotto(id: Long, drawDate: Date)

  val lotto = Lotto(3L, new Date())

  val ser: String = Serialization.write(lotto)
  println(ser) // prints value 'drawDate' as unix time
  println(Serialization.read[Lotto](ser)) // prints deserialized Lotto instance
}