hadoop运行报错: java.lang.ClassNotFoundException解决方法
2011-12-11 23:07
751 查看
作者:JesseZhang (CNZQS|JesseZhang)
博客地址:http://www.cnzqs.com
在创建自定义的Mapper时候,编译正确,但上传到集群执行时出现错误:
11/12/11 22:53:16 INFO mapred.JobClient: Task Id : attempt_201111301626_0015_m_000000_0, Status : FAILED
java.lang.RuntimeException: java.lang.ClassNotFoundException: actiondemo.MyJob$MapClass
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:866)
at org.apache.hadoop.mapreduce.JobContext.getMapperClass(JobContext.java:199)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:719)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)
at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1059)
at org.apache.hadoop.mapred.Child.main(Child.java:249)
Caused by: java.lang.ClassNotFoundException: actiondemo.MyJob$MapClass
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:247)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:819)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:864)
... 8 more
经过验证,发现问题原因及解决办法如下:
因为使用的是0.20以上的Hadoop版本,在调用jar中的自定义mapper时,需要设置setJarByClass方法,设置方法如下:
job.setJarByClass(MyJob.class);
其实,在输出日志中也有提示信息:
11/12/11 22:53:03 WARN mapred.JobClient: No job jar file set. User classes may not be found. See JobConf(Class) or JobConf#setJar(String).
job.setJarByClass(MyJob.class);
-----------------------------------------
转载请注明来源:CNZQS|JesseZhang的个人博客-《hadoop报错: java.lang.ClassNotFoundException》
本文链接地址:http://www.cnzqs.com/?p=118
博客地址:http://www.cnzqs.com
在创建自定义的Mapper时候,编译正确,但上传到集群执行时出现错误:
11/12/11 22:53:16 INFO mapred.JobClient: Task Id : attempt_201111301626_0015_m_000000_0, Status : FAILED
java.lang.RuntimeException: java.lang.ClassNotFoundException: actiondemo.MyJob$MapClass
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:866)
at org.apache.hadoop.mapreduce.JobContext.getMapperClass(JobContext.java:199)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:719)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)
at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1059)
at org.apache.hadoop.mapred.Child.main(Child.java:249)
Caused by: java.lang.ClassNotFoundException: actiondemo.MyJob$MapClass
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:247)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:819)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:864)
... 8 more
经过验证,发现问题原因及解决办法如下:
因为使用的是0.20以上的Hadoop版本,在调用jar中的自定义mapper时,需要设置setJarByClass方法,设置方法如下:
job.setJarByClass(MyJob.class);
其实,在输出日志中也有提示信息:
11/12/11 22:53:03 WARN mapred.JobClient: No job jar file set. User classes may not be found. See JobConf(Class) or JobConf#setJar(String).
job.setJarByClass(MyJob.class);
-----------------------------------------
转载请注明来源:CNZQS|JesseZhang的个人博客-《hadoop报错: java.lang.ClassNotFoundException》
本文链接地址:http://www.cnzqs.com/?p=118
相关文章推荐
- Mac系统下执行hadoop jar 运行在某包内的程序 提示java.lang.ClassNotFoundException的解决方法
- hadoop运行报错: java.lang.ClassNotFoundException解决方法
- 解决Eclipse中运行WordCount出现 java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$Token
- 解决Eclipse中运行WordCount出现 java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$TokenizerMapper问题【转】
- hadoop 伪分布式系统命令行运行java类报Exception in thread "main" java.lang.ClassNotFoundException:解决办法
- RationalRose启动提示java.lang.class.not found Exception错误的解决方法
- java.lang.ClassNotFoundException: com.mysql.jdbc.Driver 解决方法
- IDEA里运行代码时出现Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Logger的解决办法(图文详解)
- Face++ 接口 java.lang.ClassNotFoundException: org.apache.commons.collections.map.ListOrderedMap解决方法
- Rose2002启动显示java.lang.classnotfoundexception的解决方法
- [Android]java.lang.ClassNotFoundException解决方法
- java.lang.ClassNotFoundException: sun.jdbc.odbc.JdbcOdbcDriver解决方法!
- java.lang.ClassNotFoundException: com.mysql.jdbc.Driver 解决方法
- java.lang.ClassNotFoundException: com.mysql.jdbc.Driver 解决方法
- 异常 java.lang.ClassNotFoundException com.mysql.jdbc.Driver 解决方法
- 在eclipse下用java.lang.ClassNotFoundException: org.apache.commons.dbcp.BasicDataSource定义data-source Tomcat无法启动的解决方法
- Exception in thread "main" java.lang.ClassNotFoundException: 解决方法
- java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderL问题解决方法
- [置顶] Android开发之viewpager导报错误解决方法:错误代码 Caused by: java.lang.ClassNotFoundException: Didn't find class
- android studio运行程序找不到class,java.lang.ClassNotFoundException: Didn't find class,完美解决!