scala - Which JSON serialization library would fit to the following case? -

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i've got following case: i'd serialize scala case classes extend parent class var of type java.util.uuid. serialization of case classes should happen without configuration of them - no annotations , definition of custom formats. serialization hints may situated in parent class.

i tried sjson, reflection based serialization can't serialize uuid types , type based serialization forces me define formats every case class. json serialization library best fit case?

here's 1 solution lift json.

import java.util.uuid import net.liftweb.json._ import net.liftweb.json.jsonast._ import net.liftweb.json.jsondsl._ import net.liftweb.json.serialization._  sealed abstract class parent {   def uuid: uuid } case class foo(uuid: uuid, name: string) extends parent  object uuidtest extends application {   implicit val formats =  serialization.formats(notypehints) + new uuidserializer    val f = foo(uuid.randomuuid, "foo")   val ser = write(f)   println(ser)   val f2 = read[foo](ser)   assert(f == f2)    // special serializer uuid type   class uuidserializer extends serializer[uuid] {     private val class = classof[uuid]      def deserialize(implicit format: formats): partialfunction[(typeinfo, jvalue), uuid] = {       case (typeinfo(class, _), json) => json match {         case jobject(jfield("mostsig", jint(m)) :: jfield("leastsig", jint(l)) :: nil) =>           new uuid(m.longvalue, l.longvalue)         case x => throw new mappingexception("can't convert " + x + " uuid")       }     }      def serialize(implicit format: formats): partialfunction[any, jvalue] = {       case x: uuid =>         ("mostsig" -> x.getmostsignificantbits) ~ ("leastsig" -> x.getleastsignificantbits)     }   } }

it prints:

{"uuid":{"mostsig":-8054689529719995935,"leastsig":-5722404370736228056},"name":"foo"}'

another solution uses custom serializer parent type.

sealed abstract class parent {   var uuid: uuid = uuid.randomuuid } case class foo(name: string) extends parent  object uuidtest extends application {   implicit val formats =      serialization.formats(notypehints) + new parentserializer    val f = foo("foo")   val ser = write(f)   println(ser)   val f2 = read[foo](ser)   assert(f == f2)    // special serializer parent type   class parentserializer extends serializer[parent] {     def deserialize(implicit format: formats): partialfunction[(typeinfo, jvalue), parent] = {       case (t@typeinfo(cl, _), json) if (classof[parent].isassignablefrom(cl)) =>          val x = extraction.extract(json, t)(defaultformats).asinstanceof[parent]         x.uuid = (for {            jfield("mostsig", jint(m))  <- json           jfield("leastsig", jint(l)) <- json          } yield new uuid(m.longvalue, l.longvalue)).head         x     }      def serialize(implicit format: formats): partialfunction[any, jvalue] = {       case x: parent =>         extraction.decompose(x)(defaultformats) ++          jfield("mostsig", x.uuid.getmostsignificantbits) ++          jfield("leastsig", x.uuid.getleastsignificantbits)     }   } }

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