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hadoopmahoutmahout-recommender

common.AbstractJob: Unexpected -libjars while processing Job-Specific Options

all! When I use RecommenderJob in my project, I met an unexpected error. The arguments passed to the job is a String array which has values as follows:

[-libjars, /path/to/xxx.jar,/path/to/yyy.jar, 
--input, hdfs://localhost:9000/tmp/x, 
--output, hdfs://localhost:9000/tmp/y, 
--similarityClassname, 
org.apache.mahout.math.hadoop.similarity.cooccurrence.measures.TanimotoCoefficientSimilarity, 
--numRecommendations, 6, 
--tempDir, hdfs://localhost:9000/tmp/z]

After I run the job via following code:

job.run(args);

It print an ERROR as follows:

ERROR common.AbstractJob: Unexpected -libjars while processing Job-Specific Options:
usage: <command> [Generic Options] [Job-Specific Options]
Generic Options:
 -archives <paths>             comma separated archives to be unarchived
                               on the compute machines.
 -conf <configuration file>    specify an application configuration file
 -D <property=value>           use value for given property
 -files <paths>                comma separated files to be copied to the
                               map reduce cluster
 -fs <local|namenode:port>     specify a namenode
 -jt <local|jobtracker:port>   specify a job tracker
 -libjars <paths>              comma separated jar files to include in the
                               classpath.
Unexpected -libjars while processing Job-Specific Options:                      
Usage:
...

Does anybody know how to solve it. Thanks in advance!

Solution

  • Finally, I have found the solution by myself. We should not use 

    job.run(args);

    to run the job, which only deals with the Job-Specific Options. It is correct to use ToolRunner to run the job which processes the Generic Options followed by Job-Specific Options, and hence solving the problem.

    ToolRunner.run(conf, job, args);