pyspark流TaskCompletionListenerException：refCnt：0，减量：1

Question

pyspark流式读取kafka TaskCompletionListenerException：refCnt：0，减量：1

 Mono<String> response = 
  <?xml version = "1.0" encoding = "utf-8"?>
    <plane>
       <year> 1977 </year>
       <make> Cessna </make>
       <model> Skyhawk </model>
       <color> Light blue and white </color>
    </plane>