The JAR you ship to Hadoop needs to have all the required class files including third-party dependencies. Right now you're just sending it Mahout classes. Use the ".job" file that is built by the Maven targets. mvn package should make them. That has all the dependencies packaged up.
On Sun, Aug 26, 2012 at 3:32 AM, Mizrachi, Dror <dror.mizra...@intel.com> wrote: > Hi > > I'm a new Mahout user. > I tried running the follow command and got this exception - any idea why and > how to solve it? > > $ hadoop jar mahout-core-0.5.jar > org.apache.mahout.cf.taste.hadoop.item.RecommenderJob > -Dmapred.input.dir=/user/xxx/input -Dmapred.output.dir=/user/xxx/output > --recommenderClassName > org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender > --numRecommendations 10 > 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:247) > at org.apache.hadoop.util.RunJar.main(RunJar.java:179) > Caused by: java.lang.ClassNotFoundException: org.apache.commons.cli2.Option > at java.net.URLClassLoader$1.run(URLClassLoader.java:202) > at java.security.AccessController.doPrivileged(Native Method) > at java.net.URLClassLoader.findClass(URLClassLoader.java:190) > at java.lang.ClassLoader.loadClass(ClassLoader.java:306) > at java.lang.ClassLoader.loadClass(ClassLoader.java:247) > ... 3 more > > > Thanks, > Dror > > --------------------------------------------------------------------- > Intel Electronics Ltd. > > This e-mail and any attachments may contain confidential material for > the sole use of the intended recipient(s). Any review or distribution > by others is strictly prohibited. If you are not the intended > recipient, please contact the sender and delete all copies.
