ClassCastException,bean include Long key of map in 2.7.2

[lujian0571]

import com.fasterxml.jackson.databind.ObjectMapper
import com.fasterxml.jackson.module.scala.DefaultScalaModule
import com.fasterxml.jackson.module.scala.experimental.ScalaObjectMapper

class XX {
  @beans.BeanProperty
  var b = Map[String, Long]("1" -> 11L, "2" -> 22)
}
object XX {
  def main(args: Array[String]) {
    val mapper = new ObjectMapper with ScalaObjectMapper
    mapper.registerModule(DefaultScalaModule)
    //
    val x = new XX
    val s = mapper.writeValueAsString(x)
    println("s:" + s)
    //
    val mm = mapper.readValue[XX](s)
    //
    val rb = mm.b.get("1").get
    println("get:" + rb)
    println(rb == 11)
  }
}

Exception in thread "main" java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Long at scala.runtime.BoxesRunTime.unboxToLong(BoxesRunTime.java:105) at XX$.main(XX.scala:26) at XX.main(XX.scala) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:497) at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144) s:{"b":{"1":11,"2":22}}

[xgugeng]

very confusing until I realized this is a bug. Can anyone give a reply ?

[pjfanning]

Unfortunately, due to the way jackson-module-scala uses Java reflection, there are issues with reference types that wrap primitives - eg Map[String, Long], Option[Long] (caused by type erasure). At the moment, the only workaround is to use a JsonDeserialize annotation to provide the missing type information. See https://github.com/FasterXML/jackson-module-scala/pull/541 for an example.