[MAHOUT-1550] Naive Bayes training fails with Hadoop 2

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Not A Problem
• Affects Version/s: 1.0.0
• Fix Version/s: 0.10.0
• Component/s: classic
• Labels: bayesian training

Environment

Ubuntu - Mahout 1.0-SNAPSHOT - Hadoop 2

• Assignee: Unassigned
• Reporter: Paul Marret
• Created: 13/May/14 12:54
• Updated: 31/Jan/24 22:16
• Resolved: 13/May/14 15:56

Description

When using the trainnb option of the program, we get the following error:
Exception in thread "main" java.lang.IncompatibleClassChangeError: Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected
at org.apache.mahout.common.HadoopUtil.getCustomJobName(HadoopUtil.java:174)
at org.apache.mahout.common.AbstractJob.prepareJob(AbstractJob.java:614)
at org.apache.mahout.classifier.naivebayes.training.TrainNaiveBayesJob.run(TrainNaiveBayesJob.java:100)
[...]

It is possible to correct this by modifying the file mrlegacy/src/main/java/org/apache/mahout/common/HadoopUtil.java and converting the instance job (line 174) to a Job object (it is a JobContext in the current version).