无法使用 saveAsTextFile 将 RDD[String] 保存为文本文件

Question

当我尝试将我的 RDD 写入 HDFS 上的文本文件时，如下所示，出现错误。

val rdd = sc.textFile("/user/hadoop/dxld801/test.txt")
val filtered = rdd.map({line=> line.replace("\\N","NULL")})
filtered.saveAsTextFile("hdfs:///user/hadoop/dxld801/test.txt")

错误：

引起：java.lang.RuntimeException： java.lang.ClassNotFoundException：类 org.apache.hadoop.mapred.DirectFileOutputCommitter 未找到

我在 spark-shell 中运行上述所有内容，我的 spark version 是 1.4.0

这是我用来启动 shell 的命令 $SPARK_HOME/bin/spark-shell --packages com.databricks:spark-csv_2.10:1.2.0 --jars /home/hadoop/lib/native/hadoop-lzo-0.4.14.jar

我尝试用谷歌搜索找到这个类“DirectFileOutputCommitter”在哪里可用，但看起来这个类在这个世界上根本不存在。

追踪：

java.lang.RuntimeException: java.lang.RuntimeException:
> java.lang.ClassNotFoundException: Class
> org.apache.hadoop.mapred.DirectFileOutputCommitter not found
>         at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1927)
>         at org.apache.hadoop.mapred.JobConf.getOutputCommitter(JobConf.java:722)
>         at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$4.apply$mcV$sp(PairRDDFunctions.scala:983)
>         at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$4.apply(PairRDDFunctions.scala:965)
>         at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$4.apply(PairRDDFunctions.scala:965)
>         at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:148)
>         at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:109)
>         at org.apache.spark.rdd.RDD.withScope(RDD.scala:286)
>         at org.apache.spark.rdd.PairRDDFunctions.saveAsHadoopFile(PairRDDFunctions.scala:965)
>         at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$1.apply$mcV$sp(PairRDDFunctions.scala:897)
>         at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$1.apply(PairRDDFunctions.scala:897)
>         at org.apache.spark.rdd.PairRDDFunctions$$anonfun$saveAsHadoopFile$1.apply(PairRDDFunctions.scala:897)
>         at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:148)
>         at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:109)
>         at org.apache.spark.rdd.RDD.withScope(RDD.scala:286)
>         at org.apache.spark.rdd.PairRDDFunctions.saveAsHadoopFile(PairRDDFunctions.scala:896)
>         at org.apache.spark.rdd.RDD$$anonfun$saveAsTextFile$1.apply$mcV$sp(RDD.scala:1400)
>         at org.apache.spark.rdd.RDD$$anonfun$saveAsTextFile$1.apply(RDD.scala:1379)
>         at org.apache.spark.rdd.RDD$$anonfun$saveAsTextFile$1.apply(RDD.scala:1379)
>         at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:148)
>         at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:109)
>         at org.apache.spark.rdd.RDD.withScope(RDD.scala:286)
>         at org.apache.spark.rdd.RDD.saveAsTextFile(RDD.scala:1379)
>         at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:26)
>         at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:31)
>         at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:33)
>         at $iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:35)
>         at $iwC$$iwC$$iwC$$iwC.<init>(<console>:37)
>         at $iwC$$iwC$$iwC.<init>(<console>:39)
>         at $iwC$$iwC.<init>(<console>:41)
>         at $iwC.<init>(<console>:43)
>         at <init>(<console>:45)
>         at .<init>(<console>:49)
>         at .<clinit>(<console>)
>         at .<init>(<console>:7)
>         at .<clinit>(<console>)
>         at $print(<console>)
>         at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>         at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
>         at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
>         at java.lang.reflect.Method.invoke(Method.java:606)
>         at org.apache.spark.repl.SparkIMain$ReadEvalPrint.call(SparkIMain.scala:1065)
>         at org.apache.spark.repl.SparkIMain$Request.loadAndRun(SparkIMain.scala:1338)
>         at org.apache.spark.repl.SparkIMain.loadAndRunReq$1(SparkIMain.scala:840)
>         at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:871)
>         at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:819)
>         at org.apache.spark.repl.SparkILoop.reallyInterpret$1(SparkILoop.scala:857)
>         at org.apache.spark.repl.SparkILoop.interpretStartingWith(SparkILoop.scala:902)
>         at org.apache.spark.repl.SparkILoop.command(SparkILoop.scala:814)
>         at org.apache.spark.repl.SparkILoop.processLine$1(SparkILoop.scala:657)
>         at org.apache.spark.repl.SparkILoop.innerLoop$1(SparkILoop.scala:665)
>         at org.apache.spark.repl.SparkILoop.org$apache$spark$repl$SparkILoop$$loop(SparkILoop.scala:670)
>         at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply$mcZ$sp(SparkILoop.scala:997)
>         at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply(SparkILoop.scala:945)
>         at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply(SparkILoop.scala:945)
>         at scala.tools.nsc.util.ScalaClassLoader$.savingContextLoader(ScalaClassLoader.scala:135)
>         at org.apache.spark.repl.SparkILoop.org$apache$spark$repl$SparkILoop$$process(SparkILoop.scala:945)
>         at org.apache.spark.repl.SparkILoop.process(SparkILoop.scala:1059)
>         at org.apache.spark.repl.Main$.main(Main.scala:31)
>         at org.apache.spark.repl.Main.main(Main.scala)
>         at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>         at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
>         at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
>         at java.lang.reflect.Method.invoke(Method.java:606)
>         at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:664)
>         at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:169)
>         at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:192)
>         at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:111)
>         at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala) Caused by: java.lang.RuntimeException:
> java.lang.ClassNotFoundException: Class
> org.apache.hadoop.mapred.DirectFileOutputCommitter not found
>         at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1895)
>         at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1919)
>         ... 68 more Caused by: java.lang.ClassNotFoundException: Class org.apache.hadoop.mapred.DirectFileOutputCommitter not found
>         at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:1801)
>         at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1893)
>         ... 69 more

谁能帮我解决这个问题？

Answer 1

保存位置"hdfs:///user/hadoop/dxld801/test.txt" 的路径似乎错误。应该是："/user/hadoop/dxld801/test.txt" 或 "hdfs://HOSTNAME:PORT/user/hadoop/dxld801/test.txt"

同时修复该行： rdd.map({line=> line.replace("\\N","NULL")}) 到 rdd.map{line=> line.replace("\\N","NULL")}