hi, dear all :
为什么我通过 flatmap 写 liststate, extends RichFlatMapFunction, 一直报 java.lang.NoClassDefFoundError ?? stream.map(x => (x._4._1, x._4._2)) .keyBy(_._2) .flatMap(new ReceptionListStateFunction2) class ReceptionListStateFunction2 extends RichFlatMapFunction[(String, Int), List[String]] { var myState: ListState[String] = _ override def flatMap(value: (String, Int), out: Collector[List[String]]): Unit = { if (value._2 == 1) { myState.add(value._1) } val states = myState.get().iterator() val listBuf: ListBuffer[String] = new ListBuffer[String]() while (states.hasNext) { listBuf.append(states.next()) } out.collect(listBuf.toList) } } 错误日志: Exception in thread "main" java.util.concurrent.ExecutionException: scala.tools.reflect.ToolBoxError: reflective compilation has failed: cannot initialize the compiler due to java.lang.NoClassDefFoundError: Could not initialize class scala.tools.nsc.Properties$ at org.apache.flink.shaded.guava18.com.google.common.util.concurrent.AbstractFuture$Sync.getValue(AbstractFuture.java:299) at org.apache.flink.shaded.guava18.com.google.common.util.concurrent.AbstractFuture$Sync.get(AbstractFuture.java:286) at org.apache.flink.shaded.guava18.com.google.common.util.concurrent.AbstractFuture.get(AbstractFuture.java:116) at org.apache.flink.shaded.guava18.com.google.common.util.concurrent.Uninterruptibles.getUninterruptibly(Uninterruptibles.java:137) at org.apache.flink.shaded.guava18.com.google.common.cache.LocalCache$Segment.getAndRecordStats(LocalCache.java:2348) at org.apache.flink.shaded.guava18.com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2320) at org.apache.flink.shaded.guava18.com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2282) at org.apache.flink.shaded.guava18.com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2197) at org.apache.flink.shaded.guava18.com.google.common.cache.LocalCache.get(LocalCache.java:3937) at org.apache.flink.shaded.guava18.com.google.common.cache.LocalCache$LocalManualCache.get(LocalCache.java:4739) at org.apache.flink.api.scala.typeutils.TraversableSerializer$.compileCbf(TraversableSerializer.scala:184) at org.apache.flink.api.scala.typeutils.TraversableSerializer.compileCbf(TraversableSerializer.scala:51) at org.apache.flink.api.scala.typeutils.TraversableSerializer.<init>(TraversableSerializer.scala:41)