源代码：
import org.apache.spark.SparkContext
import org.apache.spark.SparkConf
object WordCount {
def main(args: Array[String]) {
val inputFile = "C://scalatext/hello.txt"
val conf = new SparkConf().setAppName("WordCount")
conf.setMaster("local")
val sc = new SparkContext(conf)
val textFile = sc.textFile(inputFile)
val wordCount = textFile.flatMap(line => line.split(" ")).map(word => (word, 1)).reduceByKey((a, b) => a + b)
//wordCount.foreach(println)
wordCount.saveAsTextFile("C://scalatext/out")
}
}
问题描述：
只要涉及到保存到本地的操作（如：wordCount.saveAsTextFile("C://scalatext/out")），就会报错。但是只是打印（如：wordCount.foreach(println)），不会报错
报错内容如下：
20/03/31 22:57:53 ERROR Shell: Failed to locate the winutils binary in the hadoop binary path java.io.IOException: Could not locate executable nullinwinutils.exe in the Hadoop binaries. at org.apache.hadoop.util.Shell.getQualifiedBinPath(Shell.java:278) at org.apache.hadoop.util.Shell.getWinUtilsPath(Shell.java:300) at org.apache.hadoop.util.Shell.<clinit>(Shell.java:293) at org.apache.hadoop.util.StringUtils.<clinit>(StringUtils.java:76) at org.apache.hadoop.mapred.FileInputFormat.setInputPaths(FileInputFormat.java:362) at org.apache.spark.SparkContext$$anonfun$hadoopFile$1$$anonfun$29.apply(SparkContext.scala:1013) at org.apache.spark.SparkContext$$anonfun$hadoopFile$1$$anonfun$29.apply(SparkContext.scala:1013) at org.apache.spark.rdd.HadoopRDD$$anonfun$getJobConf$6.apply(HadoopRDD.scala:179) at org.apache.spark.rdd.HadoopRDD$$anonfun$getJobConf$6.apply(HadoopRDD.scala:179) at scala.Option.foreach(Option.scala:257) at org.apache.spark.rdd.HadoopRDD.getJobConf(HadoopRDD.scala:179) at org.apache.spark.rdd.HadoopRDD.getPartitions(HadoopRDD.scala:198) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:252) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:250) at scala.Option.getOrElse(Option.scala:121) at org.apache.spark.rdd.RDD.partitions(RDD.scala:250) at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:252) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:250) at scala.Option.getOrElse(Option.scala:121) at org.apache.spark.rdd.RDD.partitions(RDD.scala:250) at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:252) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:250) at scala.Option.getOrElse(Option.scala:121) at org.apache.spark.rdd.RDD.partitions(RDD.scala:250) at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:252) at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:250) at scala.Option.getOrElse(Option.scala:121) at org.apache.spark.rdd.RDD.partitions(RDD.scala:250) at org.apache.spark.Partitioner$$anonfun$defaultPartitioner$2.apply(Partitioner.scala:66) at org.apache.spark.Partitioner$$anonfun$defaultPartitioner$2.apply(Partitioner.scala:66) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234) at scala.collection.immutable.List.foreach(List.scala:381) at scala.collection.TraversableLike$class.map(TraversableLike.scala:234) at scala.collection.immutable.List.map(List.scala:285) at org.apache.spark.Partitioner$.defaultPartitioner(Partitioner.scala:66) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$reduceByKey$3.apply(PairRDDFunctions.scala:331) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$reduceByKey$3.apply(PairRDDFunctions.scala:331) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112) at org.apache.spark.rdd.RDD.withScope(RDD.scala:362) at org.apache.spark.rdd.PairRDDFunctions.reduceByKey(PairRDDFunctions.scala:330) at WordCount$.main(WordCount.scala:13) at WordCount.main(WordCount.scala) 20/03/31 22:57:54 ERROR Executor: Exception in task 0.0 in stage 1.0 (TID 1) java.lang.NullPointerException at java.lang.ProcessBuilder.start(ProcessBuilder.java:1012) at org.apache.hadoop.util.Shell.runCommand(Shell.java:404) at org.apache.hadoop.util.Shell.run(Shell.java:379) at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:589) at org.apache.hadoop.util.Shell.execCommand(Shell.java:678) at org.apache.hadoop.util.Shell.execCommand(Shell.java:661) at org.apache.hadoop.fs.RawLocalFileSystem.setPermission(RawLocalFileSystem.java:639) at org.apache.hadoop.fs.FilterFileSystem.setPermission(FilterFileSystem.java:468) at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:456) at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:424) at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:905) at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:798) at org.apache.hadoop.mapred.TextOutputFormat.getRecordWriter(TextOutputFormat.java:123) at org.apache.spark.SparkHadoopWriter.open(SparkHadoopWriter.scala:90) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1$$anonfun$13.apply(PairRDDFunctions.scala:1206) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1$$anonfun$13.apply(PairRDDFunctions.scala:1197) at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:87) at org.apache.spark.scheduler.Task.run(Task.scala:99) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:322) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) 20/03/31 22:57:54 ERROR TaskSetManager: Task 0 in stage 1.0 failed 1 times; aborting job Exception in thread "main" org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 1.0 failed 1 times, most recent failure: Lost task 0.0 in stage 1.0 (TID 1, localhost, executor driver): java.lang.NullPointerException at java.lang.ProcessBuilder.start(ProcessBuilder.java:1012) at org.apache.hadoop.util.Shell.runCommand(Shell.java:404) at org.apache.hadoop.util.Shell.run(Shell.java:379) at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:589) at org.apache.hadoop.util.Shell.execCommand(Shell.java:678) at org.apache.hadoop.util.Shell.execCommand(Shell.java:661) at org.apache.hadoop.fs.RawLocalFileSystem.setPermission(RawLocalFileSystem.java:639) at org.apache.hadoop.fs.FilterFileSystem.setPermission(FilterFileSystem.java:468) at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:456) at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:424) at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:905) at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:798) at org.apache.hadoop.mapred.TextOutputFormat.getRecordWriter(TextOutputFormat.java:123) at org.apache.spark.SparkHadoopWriter.open(SparkHadoopWriter.scala:90) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1$$anonfun$13.apply(PairRDDFunctions.scala:1206) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1$$anonfun$13.apply(PairRDDFunctions.scala:1197) at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:87) at org.apache.spark.scheduler.Task.run(Task.scala:99) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:322) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) Driver stacktrace: at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$failJobAndIndependentStages(DAGScheduler.scala:1435) at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1423) at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1422) at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59) at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48) at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:1422) at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:802) at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:802) at scala.Option.foreach(Option.scala:257) at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:802) at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.doOnReceive(DAGScheduler.scala:1650) at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1605) at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1594) at org.apache.spark.util.EventLoop$$anon$1.run(EventLoop.scala:48) at org.apache.spark.scheduler.DAGScheduler.runJob(DAGScheduler.scala:628) at org.apache.spark.SparkContext.runJob(SparkContext.scala:1925) at org.apache.spark.SparkContext.runJob(SparkContext.scala:1938) at org.apache.spark.SparkContext.runJob(SparkContext.scala:1958) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1.apply$mcV$sp(PairRDDFunctions.scala:1226) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1.apply(PairRDDFunctions.scala:1168) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1.apply(PairRDDFunctions.scala:1168) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112) at org.apache.spark.rdd.RDD.withScope(RDD.scala:362) at org.apache.spark.rdd.PairRDDFunctions.saveAsHadoopDataset(PairRDDFunctions.scala:1168) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$4.apply$mcV$sp(PairRDDFunctions.scala:1071) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$4.apply(PairRDDFunctions.scala:1037) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$4.apply(PairRDDFunctions.scala:1037) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112) at org.apache.spark.rdd.RDD.withScope(RDD.scala:362) at org.apache.spark.rdd.PairRDDFunctions.saveAsHadoopFile(PairRDDFunctions.scala:1037) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$1.apply$mcV$sp(PairRDDFunctions.scala:963) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$1.apply(PairRDDFunctions.scala:963) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$1.apply(PairRDDFunctions.scala:963) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112) at org.apache.spark.rdd.RDD.withScope(RDD.scala:362) at org.apache.spark.rdd.PairRDDFunctions.saveAsHadoopFile(PairRDDFunctions.scala:962) at org.apache.spark.rdd.RDD$$anonfun$saveAsTextFile$1.apply$mcV$sp(RDD.scala:1489) at org.apache.spark.rdd.RDD$$anonfun$saveAsTextFile$1.apply(RDD.scala:1468) at org.apache.spark.rdd.RDD$$anonfun$saveAsTextFile$1.apply(RDD.scala:1468) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151) at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112) at org.apache.spark.rdd.RDD.withScope(RDD.scala:362) at org.apache.spark.rdd.RDD.saveAsTextFile(RDD.scala:1468) at WordCount$.main(WordCount.scala:15) at WordCount.main(WordCount.scala) Caused by: java.lang.NullPointerException at java.lang.ProcessBuilder.start(ProcessBuilder.java:1012) at org.apache.hadoop.util.Shell.runCommand(Shell.java:404) at org.apache.hadoop.util.Shell.run(Shell.java:379) at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:589) at org.apache.hadoop.util.Shell.execCommand(Shell.java:678) at org.apache.hadoop.util.Shell.execCommand(Shell.java:661) at org.apache.hadoop.fs.RawLocalFileSystem.setPermission(RawLocalFileSystem.java:639) at org.apache.hadoop.fs.FilterFileSystem.setPermission(FilterFileSystem.java:468) at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:456) at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:424) at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:905) at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:798) at org.apache.hadoop.mapred.TextOutputFormat.getRecordWriter(TextOutputFormat.java:123) at org.apache.spark.SparkHadoopWriter.open(SparkHadoopWriter.scala:90) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1$$anonfun$13.apply(PairRDDFunctions.scala:1206) at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopDataset$1$$anonfun$13.apply(PairRDDFunctions.scala:1197) at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:87) at org.apache.spark.scheduler.Task.run(Task.scala:99) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:322) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) Process finished with exit code 1
解决：
下载：https://github.com/srccodes/hadoop-common-2.2.0-bin，解压
HADOOP_HOME的环境变量指向解压的路径：HADOOP_HOME=C:/hadoop-common-2.2.0-bin-master
加入不配置环境遍历，还可以在代码的main方法里加入语句：
System.setProperty("hadoop.home.dir","C://hadoop-common-2.2.0-bin-master")