java.lang.ClassNotFoundException: org.apache.hadoop.util.ProgramDriver - hadoop

Question

I am trying to run mahout on my local system and when I run "./bin/mahout" I get the below mentioned error. All I am trying to do is run mahout without hadoop and try out the 20Newsgroup example.
I did "mvn compile" and "mvn install -Dmaven.test.skip=true" in the core, distribution and example directory. Not sure what else am I missing. I know that you could run mahout without Hadoop running on your system.
Appreciate if someone could help.
hadoop binary is not in PATH,HADOOP_HOME/bin,HADOOP_PREFIX/bin, running locally
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/Users/Aanchal/mahout-distribution-0.7/mahout-examples-0.7-job.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/Users/Aanchal/mahout-distribution-0.7/lib/slf4j-jcl-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/Users/Aanchal/mahout-distribution-0.7/lib/slf4j-log4j12-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/util/ProgramDriver
at org.apache.mahout.driver.MahoutDriver.main(MahoutDriver.java:96)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.util.ProgramDriver
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)

Answer 1

Add this line
CLASSPATH=${CLASSPATH}:$MAHOUT_HOME/lib/hadoop/hadoop-core-0.20.204.0.jar;
to the end of the section in mahout.sh/bat file
# add release dependencies to CLASSPATH
for f in $MAHOUT_HOME/lib/*.jar; do
CLASSPATH=${CLASSPATH}:$f;
done

Answer 2

This exception indicates that the class was not found on the classpath i.e we are trying to load the class definition and class/jar containing the class does not exist in the classpath.
Please check your PATH and HADOOP_HOME configuration and update these variables accordingly.