title: Error when running struts2 via tomcat (errors include "java.util.concurrent.ThreadPoolExecutor.runWorker..."
body: <p>I'm brand new to Java and struts2 - I've written a test app that will capture information from the user (3 fields), store the information to mysql, and then display the information in a table if the save is successful (at least I think this is what I've written.</p>
  
  <p>I'm feeling pretty lost - I have tried to search for the resolution to my issue but am unsure of which way to look first... any assistance would be beneficial! </p>
  
  <p>I'm using: Netbeans 7.3.1, tomcat 7, jdk 1.7, mysql, struts2...</p>
  
  <p>Here are the errors I'm receiving upon run in netbeans...</p>
  
  <pre><code>PackageName (run):
  
  compile-jsps:
  Starting Tomcat process...
  Waiting for Tomcat...
  Tomcat server started.
  In-place deployment at .../packageName/build/web
  deploy?config=file%3A%2Fvar%2Ffolders%2Fjz%2Fbtt5nc_x5l3g29r_g7c8f3yc0000gn%2FT%2Fcontext1380170394207520336.xml&amp;path=/Jive_OSInfo_NB
  FAIL - Deployed application at context path /packageName but context failed to start
  ...packageName/nbproject/build-impl.xml:1039: The module has not been deployed.
  See the server log for details.
  BUILD FAILED (total time: 11 seconds)
  
  
  
  Apache Tomcat Log:
  
  Sep 26, 2013 10:38:31 PM org.apache.catalina.core.ApplicationContext log
  INFO: ContextListener: contextInitialized()
  Sep 26, 2013 10:38:31 PM org.apache.catalina.core.ApplicationContext log
  INFO: SessionListener: contextInitialized()
  Sep 26, 2013 10:38:31 PM org.apache.catalina.core.ApplicationContext log
  INFO: ContextListener: attributeAdded('org.apache.jasper.compiler.TldLocationsCache', 'org.apache.jasper.compiler.TldLocationsCache@28f9ed78')
  Sep 26, 2013 10:38:34 PM org.apache.catalina.core.StandardContext filterStart
  SEVERE: Exception starting filter struts2
  Unable to load configuration. - bean - jar:file: .../build/web/WEB-INF/lib/struts2-core-2.3.4.jar!/struts-default.xml:29:72
      at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:450)
      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.addChildInternal(ContainerBase.java:901)
      at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
      at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
      at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:656)
      at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:535)
      at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1461)
      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.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:301)
      at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
      at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
      at org.apache.catalina.manager.ManagerServlet.check(ManagerServlet.java:1445)
      at org.apache.catalina.manager.ManagerServlet.deploy(ManagerServlet.java:860)
      at org.apache.catalina.manager.ManagerServlet.doGet(ManagerServlet.java:357)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
      at org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
      at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:611)
      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
      at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
      at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
      at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
      at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
      at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
      at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
      at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:724)
  Caused by: Unable to load configuration. - bean - jar:file: .../build/web/WEB-INF/lib/struts2-core-2.3.4.jar!/struts-default.xml:29:72
      at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:58)
      at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:390)
      at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:437)
      ... 44 more
  Caused by: Unable to load bean: type: class:com.opensymphony.xwork2.ObjectFactory - bean - jar:file: .../build/web/WEB-INF/lib/struts2-core-2.3.4.jar!/struts-default.xml:29:72
      at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:239)
      at org.apache.struts2.config.StrutsXmlConfigurationProvider.register(StrutsXmlConfigurationProvider.java:102)
      at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:156)
      at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:55)
      ... 46 more
  Caused by: Bean type class com.opensymphony.xwork2.ObjectFactory with the name xwork has already been loaded by bean - jar:file: ~/tomcat/lib/struts2-core-2.3.15.1.jar!/struts-default.xml:29:72 - bean - jar:file: .../build/web/WEB-INF/lib/struts2-core-2.3.4.jar!/struts-default.xml:29:72
      at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:223)
      ... 49 more
  </code></pre>