You do need a .job file and it's produced the same way, with mvn package. On Wed, Jan 18, 2012 at 12:40 PM, Martin Wignall < martin.wign...@autotrader.co.uk> wrote:
> Hi, > I am new to mahout, and am working my way through the Mahout In Action > book. Now, I'm trying to execute a RecommenderJob, and see the following > error: > > Exception in thread "main" java.lang.NoClassDefFoundError: > org/apache/commons/cli2/Option > at java.lang.Class.forName0(Native Method) > at java.lang.Class.forName(Class.java:264) > at org.apache.hadoop.util.RunJar.main(RunJar.java:149) > Caused by: java.lang.ClassNotFoundException: org.apache.commons.cli2.Option > at java.net.URLClassLoader$1.run(URLClassLoader.java:217) > at java.security.AccessController.doPrivileged(Native Method) > at java.net.URLClassLoader.findClass(URLClassLoader.java:205) > at java.lang.ClassLoader.loadClass(ClassLoader.java:321) > at java.lang.ClassLoader.loadClass(ClassLoader.java:266) > ... 3 more > > The command I'm executing is as follows: > > hadoop jar target/mahout-core-0.6-SNAPSHOT.jar > org.apache.mahout.cf.taste.hadoop.item.RecommenderJob > -Dmapred.input.dir=input/input.txt > -Dmapred.output.dir=output --usersFile input/users.txt --booleanData > > This differs slightly from the command prescribed in the Mahout In Action > book: > > > > bin/hadoop jar target/mahout-core-0.4-SNAPSHOT.job > > org.apache.mahout.cf.taste.hadoop.item.RecommenderJob > > -Dmapred.input.dir=input/input.txt > -Dmapred.output.dir=output --usersFile input/users.txt --booleanData > > Obvious differences are (i) I'm on Mahout 0.6, and (ii) I don't have a > .job file to reference, only a .jar (target/mahout-core-0.6-SNAPSHOT.jar). > I don't know if I should be referencing the .jar file in this way. > > > Now, I have built the jar myself, by executing: > > mvn -DskipTests clean package > from the core directory of Mahout. > > This appears to have worked fine, and I see the following in the > core/target directory > > drwxrwxr-x 6 martin martin 4096 2012-01-18 12:24 ./ > drwxrwxr-x 8 martin martin 4096 2012-01-18 12:24 ../ > drwxrwxr-x 3 martin martin 4096 2012-01-18 12:24 classes/ > drwxrwxr-x 4 martin martin 4096 2012-01-18 12:24 generated-sources/ > -rw-rw-r-- 1 martin martin 1641278 2012-01-18 12:24 > mahout-core-0.6-SNAPSHOT.jar > drwxrwxr-x 2 martin martin 4096 2012-01-18 12:24 maven-archiver/ > drwxrwxr-x 3 martin martin 4096 2012-01-18 12:24 test-classes/ > > Notice that there is no .job file, only a .jar. > > I'm not sure if the problem I'm seeing is due to the lack of a .job file, > or if it's something else that I've got wrong. > > Please can you help explain why I can't run the RecommenderJob? > > Many thanks, > > Martin > > > > ________________________________________ > > > This e-mail is sent on behalf of Trader Media Group Limited, Registered > Office: Auto Trader House, Cutbush Park Industrial Estate, Danehill, Lower > Earley, Reading, Berkshire, RG6 4UT(Registered in England No. 4768833). > This email and any files transmitted with it are confidential and may be > legally privileged, and intended solely for the use of the individual or > entity to whom they are addressed. If you have received this email in error > please notify the sender. This email message has been swept for the > presence of computer viruses. > >
