scala diff recursive java Map[String,Any]

diffjavamap.scala

        val skip = Set.empty[String]
        import java.util.{Map => JMap, List => JList}

        def diff(a: JMap[String, Any], b: JMap[String, Any], prefix: String = ""): Unit = {
          
          (a.keySet().asScala.toSet ++ b.keySet().asScala.toSet).filterNot(skip.contains).foreach { key =>
            val prefixKey = s"$prefix.$key"
            (Option(a.get(key)), Option(b.get(key))) match {
              case (Some(av), Some(bv)) if av.isInstanceOf[JMap[String, Any]] && bv.isInstanceOf[JMap[String, Any]] =>
                diff(av.asInstanceOf[JMap[String, Any]], bv.asInstanceOf[JMap[String, Any]], prefixKey)
              case (Some(av), Some(bv)) if av.isInstanceOf[Map[String, Any]] && bv.isInstanceOf[Map[String, Any]] =>
                diff(av.asInstanceOf[Map[String, Any]].asJava, bv.asInstanceOf[Map[String, Any]].asJava, prefixKey)
              case (Some(av), Some(bv)) if av.isInstanceOf[Seq[Any]] && bv.isInstanceOf[Seq[Any]] =>
                val aav = av.asInstanceOf[Seq[Any]]
                val bbv = av.asInstanceOf[Seq[Any]]
                aav.zip(bbv).zipWithIndex.foreach {
                  case ((x, y), idx) if x.isInstanceOf[JMap[String, Any]] && y.isInstanceOf[JMap[String, Any]] =>
                    diff(x.asInstanceOf[JMap[String, Any]], y.asInstanceOf[JMap[String, Any]], prefixKey + s".$idx")
                }
              case (Some(av), Some(bv)) if av.isInstanceOf[JList[Any]] && bv.isInstanceOf[JList[Any]] =>
                val aav = av.asInstanceOf[JList[Any]]
                val bbv = bv.asInstanceOf[JList[Any]]
                aav.asScala.zip(bbv.asScala).zipWithIndex.foreach {
                  case ((x, y), idx) if x.isInstanceOf[JMap[String, Any]] && y.isInstanceOf[JMap[String, Any]] =>
                    diff(x.asInstanceOf[JMap[String, Any]], y.asInstanceOf[JMap[String, Any]], prefixKey + s".$idx")
                }
              case (Some(av), Some(bv)) if av != bv =>
                println(s"different $prefixKey  $av $bv ${av.getClass}")
              case (Some(av), Some(bv)) if av == bv =>
                println(s"same $prefixKey  $av $bv ${av.getClass} ${bv.getClass}")
              case (Some(av), None) =>
                println(s"missing a $prefixKey $av")
              case (None, Some(bv)) =>
                println(s"missing b $prefixKey $bv")
              case _ =>
            }
          }
        }