1
所以我是Hadoop和MapReduce的新手，並試圖創建一個簡單的WordCount程序。然而，當運行它，我碰到一個錯誤：Eclipse MapReduce錯誤：UnModifiableMap
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/collections/map/UnmodifiableMap
at org.apache.hadoop.conf.Configuration$DeprecationContext.<init>(Configuration.java:409)
at org.apache.hadoop.conf.Configuration.<clinit>(Configuration.java:448)
at com.Cameron.WordCount.main(WordCount.java:51)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.collections.map.UnmodifiableMap
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 3 more
我已經在網上四處一看，原因似乎是下議院集合JAR不包含在構建路徑的事實，雖然與我的是，我仍然得到錯誤。我試過清理項目並重新啓動Eclipse無濟於事，所以任何幫助將不勝感激。我的構建路徑配置如下：
commons-collections4-4.1.jar
commons-lang-2.6.jar
commons-logging-1.2.jar
guava-11.0.2.jar
hadoop-common-2.7.2.jar
hadoop-mapreduce-client-core-2.7.2.jar
JRE System Library [JavaSE-1.7]