Apache flink 无法完成Apache Flink中的快照错误

部署后，我有一个反复出现的问题，无法在本地复制。我很乐意得到你的帮助。见日志：

[realtime-event-processor-flink-job-cluster-cc4d4b46c-8cghx] {"timestamp":"2019-04-21T08:02:15+0000","level":"INFO","thread":"flink-akka.actor.default-dispatcher-39018","logger":"org.apache.flink.runtime.executiongraph.ExecutionGraph","message":"Job  (00000000000000000000000000000000) switched from state RUNNING to FAILING.","context":"default","exception":"java.lang.Exception: Could not perform checkpoint 18039 for operator dynamic rule process -> Timestamps/Watermarks -> one to one (1/1).
org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:595)
org.apache.flink.streaming.runtime.io.BarrierBuffer.notifyCheckpoint(BarrierBuffer.java:396)
org.apache.flink.streaming.runtime.io.BarrierBuffer.processBarrier(BarrierBuffer.java:292)
org.apache.flink.streaming.runtime.io.BarrierBuffer.getNextNonBlocked(BarrierBuffer.java:200)
org.apache.flink.streaming.runtime.io.StreamTwoInputProcessor.processInput(StreamTwoInputProcessor.java:273)
org.apache.flink.streaming.runtime.tasks.TwoInputStreamTask.run(TwoInputStreamTask.java:117)
org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:300)
org.apache.flink.runtime.taskmanager.Task.run(Task.java:704)
java.lang.Thread.run(Thread.java:748)nCaused by: java.lang.Exception: Could not complete snapshot 18039 for operator dynamic rule process -> Timestamps/Watermarks -> one to one (1/1).
org.apache.flink.streaming.api.operators.AbstractStreamOperator.snapshotState(AbstractStreamOperator.java:422)
org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.checkpointStreamOperator(StreamTask.java:1113)
org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.executeCheckpointing(StreamTask.java:1055)
org.apache.flink.streaming.runtime.tasks.StreamTask.checkpointState(StreamTask.java:729)
org.apache.flink.streaming.runtime.tasks.StreamTask.performCheckpoint(StreamTask.java:641)
org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:586)nt... 8 common frames omittednCaused by: java.lang.NullPointerException: nulln"} 

操作员：

class DynamicRuleProcess
  extends KeyedBroadcastProcessFunction[String, Event, Event, DynamicRuleProcessOutput]
    with LazyLogging ...