专题 › HDFS › 错误求解Unknown protocol to job tracker

yangzong913 发表于 2014-12-5 16:07:00

此贴
java.lang.RuntimeException: java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$TokenizerMapper
的问题已解决，解决办法：
remove掉项目的所有jar包（此前这些jar包是eclipse配置hadoop之后，新增mapreduce项目自动引入的）
重新添加hadoop在win7下的安装目录下的所有jia包，是所有哦！！这样问题解决，运行成功。
似乎eclipse自动引入的jar不行！！

感谢所有关注此贴的专家，特别是回复了的专家，所有我的解决办法都列出了，供有需要的新手们参考。着实baidu上类似问题的解决思路可查的不多。

hadoop_小象 发表于 2014-12-6 15:50:35

你好，请问你是怎么解决的，我按照你说的重新导入jar包也不行啊，一直报错
14/12/06 10:41:58 WARN mapred.JobClient: No job jar file set.User classes may not be found. See JobConf(Class) or JobConf#setJar(String).
14/12/06 10:41:58 INFO input.FileInputFormat: Total input paths to process : 2
14/12/06 10:41:58 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
14/12/06 10:41:58 WARN snappy.LoadSnappy: Snappy native library not loaded
14/12/06 10:42:00 INFO mapred.JobClient: Running job: job_201412062143_0002
14/12/06 10:42:01 INFO mapred.JobClient:map 0% reduce 0%
14/12/06 10:42:11 INFO mapred.JobClient: Task Id : attempt_201412062143_0002_m_000000_0, Status : FAILED
java.lang.RuntimeException: java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$TokenizerMapper
        at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:849)
        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$4.run(Child.java:255)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:396)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1149)
        at org.apache.hadoop.mapred.Child.main(Child.java:249)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$TokenizerMapper
        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:249)
        at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:802)
        at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:847)
        ... 8 more

14/12/06 10:42:14 WARN mapred.JobClient: Error reading task outputworker3
14/12/06 10:42:14 WARN mapred.JobClient: Error reading task outputworker3
14/12/06 10:42:15 INFO mapred.JobClient: Task Id : attempt_201412062143_0002_m_000001_0, Status : FAILED
java.lang.RuntimeException: java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$TokenizerMapper
        at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:849)
        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$4.run(Child.java:255)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:396)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1149)
        at org.apache.hadoop.mapred.Child.main(Child.java:249)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$TokenizerMapper
        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:249)
        at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:802)
        at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:847)
        ... 8 more

EASONLIU 发表于 2014-12-16 22:51:51

顶顶顶！！！！！！

zxsz4084 发表于 2015-11-26 00:28:50

14/12/06 10:42:11 INFO mapred.JobClient: Task Id : attempt_201412062143_0002_m_000000_0, Status : FAILED
java.lang.RuntimeException: java.lang.ClassNotFoundException: org.apache.hadoop.examples.WordCount$TokenizerMapper
这个问题解决了吗？我也碰到这样的鬼问题了。。。tmd好烦。

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