flink sql hop函数使用udaf问题

[bigdata]

你好：
    flink1.10.1 sql在使用hop后并将udaf中merge方法名修改正确后，报如下错：为什么会说找不到匹配的merge方法呢
org.apache.flink.table.planner.codegen.CodeGenException: No matching merge method found for AggregateFunction com.autoai.cns.udaf.PercentileUDAF'
def merge(accumulator: ListBuffer[Float], its: Iterable[ListBuffer[Float]]): Unit = {
  its.foreach(i => accumulator ++ i)
}