title: Struts2 Rest plugin unable to load configuration bean
body: <p>I am trying out the struts2 Rest plugin, upon adding the jar to my lib folder this error showed up.</p>
  
  <pre><code>Jan 18, 2013 9:16:44 AM org.apache.catalina.core.StandardContext filterStart
  SEVERE: Exception starting filter struts2
  Unable to load configuration. - bean - jar:file:/C:/Users/John/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/HitPlay/WEB-INF/lib/struts2-rest-plugin-2.3.7.jar!/struts-plugin.xml:36:138
      at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:483)
      at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:74)
      at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:51)
      at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:277)
      at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:258)
      at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:382)
      at org.apache.catalina.core.ApplicationFilterConfig.&lt;init&gt;(ApplicationFilterConfig.java:103)
      at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4650)
      at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5306)
      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$Sync.innerRun(Unknown Source)
      at java.util.concurrent.FutureTask.run(Unknown Source)
      at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
      at java.lang.Thread.run(Unknown Source)
  Caused by: Unable to load configuration. - bean - jar:file:/C:/Users/John/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/HitPlay/WEB-INF/lib/struts2-rest-plugin-2.3.7.jar!/struts-plugin.xml:36:138
      at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:71)
      at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:429)
      at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:471)
      ... 16 more
  Caused by: Unable to load bean: type:org.apache.struts2.rest.handler.ContentTypeHandler class:org.apache.struts2.rest.handler.JsonLibHandler - bean - jar:file:/C:/Users/John/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/HitPlay/WEB-INF/lib/struts2-rest-plugin-2.3.7.jar!/struts-plugin.xml:36:138
      at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:245)
      at org.apache.struts2.config.StrutsXmlConfigurationProvider.register(StrutsXmlConfigurationProvider.java:102)
      at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:215)
      at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:68)
      ... 18 more
  Caused by: java.lang.NoClassDefFoundError: net/sf/json/JSONArray
      at java.lang.Class.getDeclaredConstructors0(Native Method)
      at java.lang.Class.privateGetDeclaredConstructors(Unknown Source)
      at java.lang.Class.getDeclaredConstructors(Unknown Source)
      at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:235)
      ... 21 more
  Caused by: java.lang.ClassNotFoundException: net.sf.json.JSONArray
      at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)
      at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
      ... 25 more
  </code></pre>
  
  <p>I have no idea why this is happening.  any clues?</p>