Struts2 Error when Deploying: Unable to load bean: type: class:com.opensymphony.xwork2.ObjectFactory

Question

I'm creating a basic Struts2, Maven webApp and getting this error when I deploy to Tomcat 6 or Jetty. Has anyone seen this?

  2010-07-29 15:33:38.801::WARN:  failed struts2
    Unable to load bean: type: class:com.opensymphony.xwork2.ObjectFactory - bean - jar:file:/C:/workspaces/test/test/target/work/webapp/WEB-INF/lib/struts2-core-2.1.8.1.jar!/struts-default.xml:29:72
     at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:208)
     at org.apache.struts2.config.StrutsXmlConfigurationProvider.register(StrutsXmlConfigurationProvider.java:101)
     at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reload(DefaultConfiguration.java:131)
     at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:52)
     at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:395)
     at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:452)
     at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:69)
     at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:51)
     at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97)
     at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
     at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:589)
     at org.mortbay.jetty.servlet.Context.startContext(Context.java:139)
     at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
     at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:510)
     at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
     at org.mortbay.jetty.plugin.Jetty6PluginWebAppContext.doStart(Jetty6PluginWebAppContext.java:110)
     at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
     at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152)
     at org.mortbay.jetty.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:156)
     at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
     at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152)
     at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
     at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
     at org.mortbay.jetty.Server.doStart(Server.java:222)
     at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
     at org.mortbay.jetty.plugin.Jetty6PluginServer.start(Jetty6PluginServer.java:132)
     at org.mortbay.jetty.plugin.AbstractJettyMojo.startJetty(AbstractJettyMojo.java:357)
     at org.mortbay.jetty.plugin.AbstractJettyMojo.execute(AbstractJettyMojo.java:293)
     at org.mortbay.jetty.plugin.Jetty6RunWar.execute(Jetty6RunWar.java:67)
     at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:569)
     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:539)
     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
     at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
     at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
     at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
     at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
     at java.lang.reflect.Method.invoke(Method.java:592)
     at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
     at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
     at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
     at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
    Caused by: Bean type class com.opensymphony.xwork2.ObjectFactory with the name xwork has already been loaded by bean - jar:file:/C:/workspaces/ulearn/ulearn/target/work/webapp/WEB-INF/lib/struts2-core-2.0.11.2.jar!/struts-default.xml:30:72 - bean - jar:file:/C:/workspaces/ulearn/ulearn/target/work/webapp/WEB-INF/lib/struts2-core-2.1.8.1.jar!/struts-default.xml:29:72
     at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:193)
 ... 47 more

Using Maven...

  <dependency>
   <groupId>org.apache.struts</groupId>
   <artifactId>struts2-core</artifactId>
   <version>2.1.8.1</version>
  </dependency>

web.xml

 <filter>
  <filter-name>struts2</filter-name>
  <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
 </filter>

 <filter-mapping>
  <filter-name>struts2</filter-name>
  <url-pattern>/*</url-pattern>
 </filter-mapping>

Look's pretty straight forward, I don't understand why it won't load. I followed the basic tutorial. I googled for this error message, and was unable to find anything relevant.

Answer 1

Your problem is actually quite clear if you read the stack trace:

Caused by: Bean type class com.opensymphony.xwork2.ObjectFactory with the 
name xwork has already been loaded by bean -
jar:file:/C:/workspaces/ulearn/ulearn/target/work/webapp/WEB-INF/lib/struts2-core-2.0.11.2.jar!/struts-default.xml:30:72
 - bean -
jar:file:/C:/workspaces/ulearn/ulearn/target/work/webapp/WEB-INF/lib/struts2-core-2.1.8.1.jar!/struts-default.xml:29:72

You have a copy of struts2-core-2.0.11.2.jar and a copy of struts2-core-2.1.8.1.jar in your WEB-INF/lib directories. I think you should only have one of them. Do some cleanup (running a mvn clean might be enough).

---

PS: I have no idea why you also have stuff coming from C:/workspace/test as show be the first line:

jar:file:/C:/workspaces/test/test/target/work/webapp/WEB-INF/lib/struts2-core-2.1.8.1.jar!/struts-default.xml:29:72

There is definitely something weird and messy with your classpath. I don't have any explanation beyond the one I gave above though.

Answer 2

Agree with the above answer

Check your library and classpath for the above jars and fix them

Sometimes even if the jars are not seen in the IDE, they are present int the build files, So a fix of the classpath and a CLEAN AND BUILD should resolve the problem.