title: NoClassDefFoundError using struts 2
body: <p>I am building an app using struts,i go through with the similar questions asked on StackOverflow but could not get the correct answer.</p>
  
  <hr>
  
  <pre><code>    Aug 25, 2014 5:15:41 PM com.opensymphony.xwork2.config.providers.XmlConfigurationProvider info
  INFO: Parsing configuration file [struts-default.xml]
  Aug 25, 2014 5:15:41 PM org.apache.catalina.core.StandardContext filterStart
  SEVERE: Exception starting filter struts2
  java.lang.NoClassDefFoundError: org/apache/commons/lang3/StringUtils
      at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:211)
      at org.apache.struts2.config.StrutsXmlConfigurationProvider.register(StrutsXmlConfigurationProvider.java:102)
      at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:234)
      at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:67)
      at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:445)
      at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:489)
      at org.apache.struts2.dispatcher.FilterDispatcher.init(FilterDispatcher.java:193)
      at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:281)
      at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:262)
      at org.apache.catalina.core.ApplicationFilterConfig.&lt;init&gt;(ApplicationFilterConfig.java:107)
      at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4775)
      at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5452)
      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
      at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
      at java.util.concurrent.FutureTask.run(Unknown Source)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
      at java.lang.Thread.run(Unknown Source)
  Caused by: java.lang.ClassNotFoundException: org.apache.commons.lang3.StringUtils
      at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1702)
      at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547)
      ... 20 more
  
  Aug 25, 2014 5:15:41 PM org.apache.catalina.core.StandardContext startInternal
  SEVERE: Error filterStart
  </code></pre>
  
  <p>This is a list of jar file am using</p>
  
  <pre><code>commons-fileupload-1.3.1
  commons-io-2.2
  commons-lang-2.4
  commons-logging-1.1.3
  commons-logging-api-1.1
  freemarker-2.3.19
  javassist-3.11.0.GA
  ognl-3.0.6
  struts2-core-2.3.16.3
  xwork-core-2.3.16.3
  </code></pre>