相关疑难解决方法(0)

我试图按照此页面上的说明操作:http: //www.michael-noll.com/tutorials/writing-an-hadoop-mapreduce-program-in-python/

$bin/hadoop jar contrib/streaming/hadoop-streaming-1.0.4.jar -input /user/root/wordcountpythontxt -output /user/root/wordcountpythontxt-output -mapper /user/root/wordcountpython/mapper.py -reducer /user/root/wordcountpython/reducer.py -file /user/root/mapper.py -file /user/root/reducer.py

它说

File: /user/root/mapper.py does not exist, or is not readable.
Streaming Command Fail

当我浏览网址时:jobdetails.jsp /

我发现很多例外

java.lang.RuntimeException: Error in configuring object
    at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:93)
    at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:64)
    at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:117)
    at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:432)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:372)
    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:1121)
    at org.apache.hadoop.mapred.Child.main(Child.java:249)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:88)
    ... 9 more
Caused by: …