Pickling - possible race condition?

[tomasherman]

Hey guys,

i have following problem:

i am trying to pickle this case class

trait GuiMessage
case class SkillMatrix(operators: Seq[String], skills: Seq[String], enabledSkills: Seq[(String,String)]) extends GuiMessage

The problem is that when i try to pickle this class from two different threads at the same time, i get following:

{x:Any => val pickled = x.asInstanceOf[SkillMatrix].pickle.value; println(s"pickling $x into $pickled");pickled}) //this function is called from two different threads

pickling SkillMatrix(List(1234, 4312),List(skill1, skill2),List((1234,skill1), (1234,skill2), (4312,skill1))) into {
  "tpe": "com.spinoco.horus.message.GuiMessage.SkillMessage.SkillMatrix",
  "operators": {
    "tpe": "scala.collection.Seq[java.lang.String]",
    "elems": [
      "1234",
      "4312"
    ]
  },
  "skills": {
    "tpe": "scala.collection.Seq[java.lang.String]",
    "elems": [
      "skill1",
      "skill2"
    ]
  },
  "enabledSkills": {
    "tpe": "scala.collection.Seq[scala.Tuple2[java.lang.String,java.lang.String]]",
    "elems": [
      { "$ref": 2 },
      {
      "tpe": "scala.Tuple2[java.lang.String,java.lang.String]",
      "a": "1234",
      "b": "skill2"
    },
      { "$ref": 4 }
    ]
  }
}
pickling SkillMatrix(List(1234, 4312),List(skill1, skill2),List((1234,skill1),(1234,skill2),(4312,skill1))) into {
  "tpe": "com.spinoco.horus.message.GuiMessage.SkillMessage.SkillMatrix",
  "operators": {
    "tpe": "scala.collection.Seq[java.lang.String]",
    "elems": [
      "1234",
      "4312"
    ]
  },
  "skills": {
    "tpe": "scala.collection.Seq[java.lang.String]",
    "elems": [
      "skill1",
      "skill2"
    ]
  },
  "enabledSkills": {
    "tpe": "scala.collection.Seq[scala.Tuple2[java.lang.String,java.lang.String]]",
    "elems": [
      {
      "tpe": "scala.Tuple2[java.lang.String,java.lang.String]",
      "a": "1234",
      "b": "skill1"
    },
      { "$ref": 3 },
      {
      "tpe": "scala.Tuple2[java.lang.String,java.lang.String]",
      "a": "4312",
      "b": "skill1"
    }
    ]
  }
}

as you can see, there are some really odd "$ref"s that i don't care for. Am i doing something wrong or is that error on your end? To me, it looks like some kind of race condition when pickling same object in two places at the same time.

Thanks

[jsuereth]

The "$ref" bits are expected. Pickling is trying to share the previous values, rather than re-serialize them.

The question is, what version of pickling was this? Could you try again with master and see if it's still an issue?