我已经在伪分布式模式下配置了hadoop。我已经成功地创建了序列文件和tf-idf向量（使用seq2sparse），并尝试从命令行运行mahout kmeans，如下所示：
mahout kmeans-i/user/mahout/vectors/tfidf vectors-c/user/mahout/cluster centroids-o/user/mahout/kmeans-dm org.apache.mahout.commom.distance.cosinedistancemeasure-x 10-k 20-ow--clustering-cl
我得到以下错误：

Running on hadoop, using /usr/local/hadoop/bin/hadoop and HADOOP_CONF_DIR=
MAHOUT-JOB: /home/mahout/apache-mahout-distribution-0.10.1/mahout-examples-0.10.1-job.jar
15/07/01 11:14:15 INFO AbstractJob: Command line arguments: {--clustering=null, --clusters=[/user/mahout/cluster-centroids], --convergenceDelta=[0.5], --distanceMeasure=[org.apache.mahout.commom.distance.CosineDistanceMeasure], --endPhase=[2147483647], --input=[/user/mahout/vectors/tfidf-vectors], --maxIter=[10], --method=[mapreduce], --numClusters=[20], --output=[/user/mahout/kmeans], --overwrite=null, --startPhase=[0], --tempDir=[temp]}
15/07/01 11:14:16 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Exception in thread "main" java.lang.IllegalStateException: java.lang.ClassNotFoundException: org.apache.mahout.commom.distance.CosineDistanceMeasure
    at org.apache.mahout.common.ClassUtils.instantiateAs(ClassUtils.java:30)
    at org.apache.mahout.clustering.kmeans.KMeansDriver.run(KMeansDriver.java:91)
    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    at org.apache.mahout.clustering.kmeans.KMeansDriver.main(KMeansDriver.java:47)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:71)
    at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:144)
    at org.apache.hadoop.util.ProgramDriver.driver(ProgramDriver.java:152)
    at org.apache.mahout.driver.MahoutDriver.main(MahoutDriver.java:195)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
    at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Caused by: java.lang.ClassNotFoundException: org.apache.mahout.commom.distance.CosineDistanceMeasure
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:191)
    at org.apache.mahout.common.ClassUtils.instantiateAs(ClassUtils.java:28)
    ... 17 more

我试过设置 HADOOP_CLASSPATH 到所需的jar文件。