锐客网

  1. 首页 > 睿知 > it技术 > >

Hadoop 运行jar包时 java.lang.ClassNotFoundException: Class com.zhen.mr.RunJob$HotMapper not found

IT知识exception:classNotFounException

学向勤中得，萤窗万卷书。这篇文章主要讲述Hadoop 运行jar包时 java.lang.ClassNotFoundException: Class com.zhen.mr.RunJob$HotMapper not found相关的知识，希望能为你提供帮助。
错误如下

Error: java.lang.RuntimeException: java.lang.ClassNotFoundException: Class com.zhen.mr.RunJob$HotMapper not found at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2154) at org.apache.hadoop.mapreduce.task.JobContextImpl.getMapperClass(JobContextImpl.java:186) at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:742) at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341) at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:163) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:422) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1692) at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158) Caused by: java.lang.ClassNotFoundException: Class com.zhen.mr.RunJob$HotMapper not found at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:2060) at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2152) ... 8 more

错误出现之前还有警告提示，如下
WARN mapreduce.JobResourceUploader: No job jar file set.User classes may not be found. See Job or Job#setJar(String).

提示说没有设置job jar
解决方法：
代码中给job对象set一下
job.setJarByClass(RunJob.class);

【Hadoop 运行jar包时 java.lang.ClassNotFoundException: Class com.zhen.mr.RunJob$HotMapper not found】然后再打包运行就ok了。

    推荐阅读


    上一篇：Android 开发之 ---- bootloader （LK）

    下一篇：Android中对Handle机制的理解