Java Web 应用程序错误 - 不明白为什么现在会发生

Java Web Application Error - Can't understand why it's happening now

提问by robbie

I am using eclipse and I can build the webapp and deploy it to Jboss4.2.1. It was working previously and I haven't changed anything really extensively to make this error come about. When I go to the webapp thru my browser, I previously have been signing in with a generic username and then I could use my webapp as usual.

我正在使用 eclipse，我可以构建 webapp 并将其部署到 Jboss4.2.1。它以前工作过，我没有真正广泛地改变任何东西来使这个错误发生。当我通过浏览器访问 webapp 时，我之前一直使用通用用户名登录，然后我可以像往常一样使用我的 webapp。

Now when I go to the webapp thru the browser, this error occurs repeatedly and will not show anything. Here is the error that I am receiving:

现在，当我通过浏览器访问 webapp 时，此错误会反复发生并且不会显示任何内容。这是我收到的错误：

07:55:06,174 INFO  [security] User '' attempting login via SiteMinder...
07:55:06,174 INFO  [security] User '' attempting login via SiteMinder...
07:55:06,174 ERROR [[jsp]] Servlet.service() for servlet jsp threw exception
java.lang.LinkageError: Class javax/el/ExpressionFactory violates loader constraints
    at org.apache.jsp.WEB_002dINF.jsp.layout.header_jsp._jspx_meth_c_005fset_005f0(header_jsp.java:207)
    at org.apache.jsp.WEB_002dINF.jsp.layout.header_jsp._jspx_meth_c_005fif_005f0(header_jsp.java:179)
    at org.apache.jsp.WEB_002dINF.jsp.layout.header_jsp._jspService(header_jsp.java:82)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:387)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:687)
    at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:590)
    at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:505)
    at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:968)
    at org.apache.jasper.runtime.PageContextImpl.doInclude(PageContextImpl.java:643)
    at org.apache.jasper.runtime.PageContextImpl.include(PageContextImpl.java:637)
    at net.sourceforge.stripes.tag.layout.LayoutRenderTag.doEndTag(LayoutRenderTag.java:122)
    at org.apache.jsp.WEB_002dINF.jsp.layout.layout_jsp._jspx_meth_stripes_005flayout_002drender_005f0(layout_jsp.java:796)
    at org.apache.jsp.WEB_002dINF.jsp.layout.layout_jsp._jspx_meth_stripes_005flayout_002dcomponent_005f2(layout_jsp.java:759)
    at org.apache.jsp.WEB_002dINF.jsp.layout.layout_jsp._jspService(layout_jsp.java:200)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:387)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:687)
    at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:590)
    at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:505)
    at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:968)
    at org.apache.jasper.runtime.PageContextImpl.doInclude(PageContextImpl.java:643)
    at org.apache.jasper.runtime.PageContextImpl.include(PageContextImpl.java:637)
    at net.sourceforge.stripes.tag.layout.LayoutRenderTag.doEndTag(LayoutRenderTag.java:122)
    at org.apache.jsp.view.public_.login_jsp._jspService(login_jsp.java:335)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:387)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at net.sourceforge.stripes.controller.StripesFilter.doFilter(StripesFilter.java:180)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:112)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:265)
    at org.acegisecurity.ui.switchuser.SwitchUserProcessingFilter.doFilter(SwitchUserProcessingFilter.java:341)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.intercept.web.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:107)
    at org.acegisecurity.intercept.web.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:72)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:110)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:110)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.wrapper.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:81)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:229)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:229)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:286)
    at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
    at org.acegisecurity.util.FilterChainProxy.doFilter(FilterChainProxy.java:149)
    at org.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:98)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
    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:230)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179)
    at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
    at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:241)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:580)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
    at java.lang.Thread.run(Thread.java:595)

Any help would be greatly appreciated.

任何帮助将不胜感激。

回答by BalusC

The runtime classpath is likely polluted with duplicate and/or different versions of EL API.

运行时类路径可能被重复和/或不同版本的 EL API 污染。

Normally, the EL API is already shipped with servletcontainer/appserver in question. You should in no waycopy/duplicate/move its libraries somewhere else, such as into webapp's /WEB-INF/libor more worse the JRE's /lib. Cleanup the classpath from all duplicate and/or different versioned classes / JAR files. It may otherwise lead to exceptions like this.

通常，EL API 已经随 servletcontainer/appserver 一起提供。您绝不应该将其库复制/复制/移动到其他地方，例如进入 webapp/WEB-INF/lib或更糟的 JRE 的/lib. 从所有重复的和/或不同版本的类/JAR 文件中清除类路径。否则可能会导致此类异常。

A common mistake among starters is namely that they copy the servletcontainer/appserver's libraries into /WEB-INF/libbecause they got compilation errors in the IDE (javax.servletnot found and so on). Copying the libraries is the wrongsolution. You should rather have integrated the server in the same IDE and configured the IDE project to reference/associate the server in question so that the IDE will automagically take its libraries in the project's buildpath.

初学者的一个常见错误是他们将 servletcontainer/appserver 的库复制到其中，/WEB-INF/lib因为他们在 IDE 中遇到编译错误（javax.servlet未找到等）。复制库是错误的解决方案。您应该将服务器集成到同一个 IDE 中，并将 IDE 项目配置为引用/关联相关服务器，以便 IDE 会自动将其库放在项目的构建路径中。

回答by Zinc

I'm sure you have but restart your services...

我确定你有但重新启动你的服务......

回答by Nils Schmidt

Googling a bit around indicates, that other applications have similar problems, usually it is due to some compatibility problems with el libraries. You may wanne check for that.

谷歌搜索一下表明，其他应用程序也有类似的问题，通常是由于与 el 库的一些兼容性问题。你可能想检查一下。

回答by Elister

I faced a similar exception although in entirely different context however it should be valid here as well.

尽管在完全不同的上下文中，我也遇到了类似的异常，但它在这里也应该有效。

Usually this means that you have more than one copy of the offending class in classpath.

通常这意味着您在类路径中拥有多个违规类的副本。

I'd try to find if javax.el.ExpressionFactory.class is present multiple times. (may be it is there in server's lib as well as applications lib)

我会尝试查找 javax.el.E​​xpressionFactory.class 是否多次出现。（可能它在服务器的库和应用程序库中）