flink1.10.1 merge??????????scala??????????????????flink??bug??

[bigdata]

??????
org.apache.flink.table.planner.codegen.CodeGenException: No matching merge 
method found for AggregateFunction 
com.autoai.cns.udaf.PercentileUDAF'????????????????merge????????scala??????????????????????????????java??????????????????
    ????????????flink1.10.1 
merge??????????scala??????????????????flink??bug??
????????????????
def merge(accumulator: ListBuffer[Float], its: 
java.lang.Iterable[ListBuffer[Float]]): Unit = {
//    its.forEach(i => accumulator ++ i)
    val iter = its.iterator()
    while (iter.hasNext) {
      val a = iter.next()
      accumulator ++ a
    }
  }