hadoop-2.6.0-hadoop.dll-winutils.exe

windows上eclipse运行hadoop程序报NullPointerException错 log4j:WARN No appenders could be found for logger (org.apache.hadoop.metrics2.lib.MutableMetricsFactory). log4j:WARN Please initialize the log4j system properly. log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info. Exception in thread "main" java.lang.NullPointerException     at java.lang.ProcessBuilder.start(ProcessBuilder.java:1010)     at org.apache.hadoop.util.Shell.runCommand(Shell.java:482)     at org.apache.hadoop.util.Shell.run(Shell.java:455)     at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:715)     at org.apache.hadoop.util.Shell.execCommand(Shell.java:808)     at org.apache.hadoop.util.Shell.execCommand(Shell.java:791)     at org.apache.hadoop.fs.RawLocalFileSystem.setPermission(RawLocalFileSystem.java:656)     at org.apache.hadoop.fs.RawLocalFileSystem.mkdirs(RawLocalFileSystem.java:444)     at org.apache.hadoop.fs.FilterFileSystem.mkdirs(FilterFileSystem.java:293)     at org.apache.hadoop.mapreduce.JobSubmissionFiles.getStagingDir(JobSubmissionFiles.java:133)     at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:437)     at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1296)     at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1293)     at java.security.AccessController.doPrivileged(Native Method)     at javax.security.auth.Subject.doAs(Subject.java:415)     at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1628)     at org.apache.hadoop.mapreduce.Job.submit(Job.java:1293)     at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1314)     at com.lxz.mr.WCApp.main(WCApp.java:27) 原因是hadoop.dll文件和winutils.exe文件缺失了。解决步骤为： 1，下载这两个文件，下载地址：https://download.csdn.net/download/luxiangzhou/10635946 2，解压之后，把hadoop.dll拷贝到C:\Windows\System32下面 3，创建环境变量HADOOP_HOME，然后把winutils.exe文件拷贝到${HADOOP_HOME}/bin目录下