[MAHOUT-351] can not set usersFile as null when run org.apache.mahout.cf.taste.hadoop.item.RecommenderJob

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.4
• Fix Version/s: 0.4
• Labels: RecommenderJob usersFile
• Assignee: Unassigned
• Reporter: Han Hui Wen
• Created: 30/Mar/10 09:04
• Updated: 31/Jan/24 22:11
• Resolved: 30/Mar/10 10:18

Description

I　want to get all users recommendations using RecommenderJob.
it seems need not set the usersFile parameters,

In Class:RecommenderMapper.java

String usersFilePathString = jobConf.get(USERS_FILE);
if (usersFilePathString == null)

{ usersToRecommendFor = null; }

else {
usersToRecommendFor = new FastIDSet();
Path usersFilePath = new Path(usersFilePathString).makeQualified(fs);
FSDataInputStream in = fs.open(usersFilePath);
for (String line : new FileLineIterable(in))

{ usersToRecommendFor.add(Long.parseLong(line)); }

}

if ((usersToRecommendFor != null) && !usersToRecommendFor.contains(userID.get()))

{ return; }

but when I　ｉnore userFile parameters ,get following error:

run job :
randy@dan:~/app/steer/item$ hadoop org.apache.mahout.cf.taste.hadoop.item.RecommenderJob -Dmapred.job.name=HADOOP_REC_tap_tag\ -Dmapred.reduce.tasks=200 --input /steer/item/in --tempDir /steer/item/temp --output /steer/item/out --jarFile mahout-0.4-SNAPSHOT.jar --numRecommendations 10

Exception in thread "main" java.lang.NullPointerException
at java.util.Hashtable.put(Hashtable.java:394)
at java.util.Properties.setProperty(Properties.java:143)
at org.apache.hadoop.conf.Configuration.set(Configuration.java:403)
at org.apache.mahout.cf.taste.hadoop.item.RecommenderJob.run(RecommenderJob.java:110)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79)
at org.apache.mahout.cf.taste.hadoop.item.RecommenderJob.main(RecommenderJob.java:117)