我正在尝试使用以下代码生成客户统计信息。这是一个组合ByKey转换。我得到一个ArrayIndexOutOfBounds异常。想知道原因，但我没有得到任何提示。请任何人澄清一下，为什么我会得到这个例外。非常感谢。
def createComb = (t:Array[String]) => {
val total = t(5).toDouble
val q = t(4).toInt
(total/q, total/q, q, total)}
def mergeValues : ((Double,Double,Int,Double), Array[String]) =>
(Double,Double,Int,Double) =
{case((mx,mn,q,tot),t) =>{
val total = t(5).toDouble
val quan = t(4).toInt
val mxx = scala.math.max(mx, total/q)
val minn = scala.math.min(mn, total/q)
(mxx,minn,quan+q,total+tot)}}
def mergeComb:((Double,Double,Int,Double),(Double,Double,Int,Double)) =>
(Double,Double,Int,Double) =
{ case((mx1,mn1,q1,tot1),(mx2,mn2,q2,tot2)) =>
(scala.math.max(mx1,mx2), scala.math.min(mn1,mn2), q1+q2, tot1+tot2)}
val statsOfCust = productsTotalByKey.combineByKey(createComb, mergeValues, mergeComb, new org.apache.spark.HashPartitioner(productsTotalByKey.partitions.size))
以下是在spark集群上执行上述代码后，在RDD上执行时得到的输出。
scala> statsOfCust.first
[Stage 22:> (0 + 1) / 2]18/11/17 21:26:31 WARN TaskSetManager: Lost task 0.0 in stage 22.0 (TID 26, wn01.itversity.com, executor 9): java.lang.ArrayIndexOutOfBoundsException: 5
at $line80.$read$$iw$$iw$$iw$$iw$$iw$$iw$$iw$$iw$$anonfun$createComb$1.apply(<console>:24)
at $line80.$read$$iw$$iw$$iw$$iw$$iw$$iw$$iw$$iw$$anonfun$createComb$1.apply(<console>:23)
at org.apache.spark.util.collection.ExternalSorter$$anonfun$5.apply(ExternalSorter.scala:189)
at org.apache.spark.util.collection.ExternalSorter$$anonfun$5.apply(ExternalSorter.scala:188)
at org.apache.spark.util.collection.AppendOnlyMap.changeValue(AppendOnlyMap.scala:144)
at org.apache.spark.util.collection.SizeTrackingAppendOnlyMap.changeValue(SizeTrackingAppendOnlyMap.scala:32)
at org.apache.spark.util.collection.ExternalSorter.insertAll(ExternalSorter.scala:194)
at org.apache.spark.shuffle.sort.SortShuffleWriter.write(SortShuffleWriter.scala:63)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:96)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:53)
at org.apache.spark.scheduler.Task.run(Task.scala:109)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:345)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Driver stacktrace:
at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$failJobAndIndependentStages(DAGScheduler.scala:1599)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1587)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1586)
at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:1586)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:831)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:831)
at scala.Option.foreach(Option.scala:257)
at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:831)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.doOnReceive(DAGScheduler.scala:1820)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1769)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1758)
at org.apache.spark.util.EventLoop$$anon$1.run(EventLoop.scala:48)
at org.apache.spark.scheduler.DAGScheduler.runJob(DAGScheduler.scala:642)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:2034)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:2055)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:2074)
at org.apache.spark.rdd.RDD$$anonfun$take$1.apply(RDD.scala:1358)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:363)
at org.apache.spark.rdd.RDD.take(RDD.scala:1331)
at org.apache.spark.rdd.RDD$$anonfun$first$1.apply(RDD.scala:1372)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:363)
at org.apache.spark.rdd.RDD.first(RDD.scala:1371)
... 49 elided
Caused by: java.lang.ArrayIndexOutOfBoundsException: 5
at $anonfun$createComb$1.apply(<console>:24)
at $anonfun$createComb$1.apply(<console>:23)
at org.apache.spark.util.collection.ExternalSorter$$anonfun$5.apply(ExternalSorter.scala:189)
at org.apache.spark.util.collection.ExternalSorter$$anonfun$5.apply(ExternalSorter.scala:188)
at org.apache.spark.util.collection.AppendOnlyMap.changeValue(AppendOnlyMap.scala:144)
at org.apache.spark.util.collection.SizeTrackingAppendOnlyMap.changeValue(SizeTrackingAppendOnlyMap.scala:32)
at org.apache.spark.util.collection.ExternalSorter.insertAll(ExternalSorter.scala:194)
at org.apache.spark.shuffle.sort.SortShuffleWriter.write(SortShuffleWriter.scala:63)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:96)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:53)
at org.apache.spark.scheduler.Task.run(Task.scala:109)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:345)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
如果假设t数组至少有6个元素，createComb方法似乎有问题。
这只是一个快速的玩笑。如果有帮助，请告诉我。如果没有，我将尝试进一步调查：(