新手求教，忘大神解决

Question

严重: Servlet.service() for servlet jsp threw exception
java.lang.NoSuchMethodError: com.opensymphony.xwork2.util.ValueStack.findValue(Ljava/lang/String;Ljava/lang/Class;Z)Ljava/lang/Object;
at org.apache.struts2.components.Property.start(Property.java:159)
at org.apache.struts2.views.freeer.tags.CallbackWriter.onStart(CallbackWriter.java:73)
at freeer.core.Environment.visit(Environment.java:296)
at freeer.core.UnifiedCall.accept(UnifiedCall.java:130)
at freeer.core.Environment.visit(Environment.java:210)
at freeer.core.MixedContent.accept(MixedContent.java:92)
at freeer.core.Environment.visit(Environment.java:210)
at freeer.core.ConditionalBlock.accept(ConditionalBlock.java:79)
at freeer.core.Environment.visit(Environment.java:210)
at freeer.core.MixedContent.accept(MixedContent.java:92)
at freeer.core.Environment.visit(Environment.java:210)
at freeer.core.Environment.include(Environment.java:1483)
at freeer.core.Include.accept(Include.java:169)
at freeer.core.Environment.visit(Environment.java:210)
at freeer.core.MixedContent.accept(MixedContent.java:92)
at freeer.core.Environment.visit(Environment.java:210)
at freeer.core.Environment.process(Environment.java:190)
at freeer.template.Template.process(Template.java:237)
at org.apache.struts2.components.template.FreeerTemplateEngine.renderTemplate(FreeerTemplateEngine.java:157)
at org.apache.struts2.components.UIBean.mergeTemplate(UIBean.java:559)
at org.apache.struts2.components.UIBean.end(UIBean.java:513)
at org.apache.struts2.views.jsp.ComponentTagSupport.doEndTag(ComponentTagSupport.java:42)
at org.apache.jsp.login3_jsp._jspx_meth_s_005ftextfield_005f0(login3_jsp.java:230)
at org.apache.jsp.login3_jsp._jspx_meth_s_005fform_005f0(login3_jsp.java:140)
at org.apache.jsp.login3_jsp._jspService(login3_jsp.java:100)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:386)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:428)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:619)
怎么解决啊，看不懂，刚学的

Answer 1

at org.apache.jsp.login3_jsp._jspx_meth_s_005ftextfield_005f0(login3_jsp.java:230)
at org.apache.jsp.login3_jsp._jspx_meth_s_005fform_005f0(login3_jsp.java:140)
at org.apache.jsp.login3_jsp._jspService(login3_jsp.java:100)tomcat\work\Catalina\localhost 找到login3_jsp.java文件，看看对应行数有什么错误。java.lang.NoSuchMethodError: com.opensymphony.xwork2.util.ValueStack.findValue(Ljava/lang/String;Ljava/lang/Class;Z)Ljava/lang/Object;findValue是不是用错了。

Answer 2

jar包冲突,搜索有两个jar包含ValueStack这个类 
xwork-2.1.1.jar 
xwork-coue-2.1.6.jar 
把一个去掉就好了