java - eclipse中突然出现ClassNotFoundException

Question

我正在使用 eclipse 3.4.1、jre6、tomcat 6、jsf 1.2 和 rich faces 3。应用程序工作得很好，突然间它开始在浏览器中生成以下错误。

Sorry, a fatal error has occurred. The error has been logged.Please log in again. 

而 eclipse 中的控制台显示:-

SEVERE: Servlet.service() for servlet jsp threw exception
java.lang.ClassNotFoundException: org.college.ui.bean.SearchUserBean
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.apache.myfaces.shared_impl.util.ClassUtils.classForName(ClassUtils.java:141)
at org.apache.myfaces.shared_impl.util.ClassUtils.simpleClassForName(ClassUtils.java:160)
at org.apache.myfaces.shared_impl.util.ClassUtils.newInstance(ClassUtils.java:268)
at org.apache.myfaces.config.ManagedBeanBuilder.buildManagedBean(ManagedBeanBuilder.java:49)
at org.apache.myfaces.el.VariableResolverImpl.resolveVariable(VariableResolverImpl.java:314)
at org.apache.myfaces.trinidadinternal.el.TrinidadVariableResolver.resolveVariable(TrinidadVariableResolver.java:54)
at org.apache.myfaces.el.ValueBindingImpl$ELVariableResolver.resolveVariable(ValueBindingImpl.java:570)
at org.apache.commons.el.NamedValue.evaluate(NamedValue.java:124)
at org.apache.commons.el.ComplexValue.evaluate(ComplexValue.java:140)
at org.apache.myfaces.el.ValueBindingImpl.getValue(ValueBindingImpl.java:386)
at javax.faces.component.UIOutput.getValue(UIOutput.java:80)
at org.apache.myfaces.shared_impl.renderkit.RendererUtils.getStringValue(RendererUtils.java:223)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlTextRendererBase.renderInput(HtmlTextRendererBase.java:135)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlTextRendererBase.encodeEnd(HtmlTextRendererBase.java:53)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:539)
at org.apache.myfaces.shared_impl.renderkit.RendererUtils.renderChild(RendererUtils.java:419)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlGridRendererBase.renderChildren(HtmlGridRendererBase.java:229)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlGridRendererBase.encodeEnd(HtmlGridRendererBase.java:101)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:539)
at org.apache.myfaces.shared_impl.renderkit.RendererUtils.renderChild(RendererUtils.java:419)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlGridRendererBase.renderChildren(HtmlGridRendererBase.java:229)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlGridRendererBase.encodeEnd(HtmlGridRendererBase.java:101)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:539)
at org.apache.myfaces.shared_impl.renderkit.RendererUtils.renderChild(RendererUtils.java:419)
at org.apache.myfaces.shared_impl.renderkit.RendererUtils.renderChildren(RendererUtils.java:400)
at org.apache.myfaces.shared_impl.renderkit.html.HtmlGroupRendererBase.encodeEnd(HtmlGroupRendererBase.java:78)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:539)
at javax.faces.webapp.UIComponentTag.encodeEnd(UIComponentTag.java:498)
at javax.faces.webapp.UIComponentTag.doEndTag(UIComponentTag.java:366)
at org.apache.myfaces.shared_impl.taglib.UIComponentBodyTagBase.doEndTag(UIComponentBodyTagBase.java:57)
at org.apache.jsp.pages.login_jsp._jspx_meth_h_005fpanelGroup_005f0(login_jsp.java:254)
at org.apache.jsp.pages.login_jsp._jspx_meth_h_005fform_005f0(login_jsp.java:199)
at org.apache.jsp.pages.login_jsp._jspx_meth_f_005fview_005f0(login_jsp.java:165)
at org.apache.jsp.pages.login_jsp._jspService(login_jsp.java:129)
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:388)
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.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302)
at org.apache.myfaces.context.servlet.ServletExternalContextImpl.dispatch(ServletExternalContextImpl.java:419)
at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:43)
at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:43)
at org.apache.myfaces.trinidadinternal.context.FacesContextFactoryImpl$OverrideDispatch.dispatch(FacesContextFactoryImpl.java:260)
at org.apache.myfaces.application.jsp.JspViewHandlerImpl.renderView(JspViewHandlerImpl.java:211)
at org.apache.myfaces.trinidadinternal.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:182)
at org.apache.myfaces.lifecycle.RenderResponseExecutor.execute(RenderResponseExecutor.java:41)
at org.apache.myfaces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:132)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:140)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:147)
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.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302)
at org.apache.jasper.runtime.PageContextImpl.doForward(PageContextImpl.java:709)
at org.apache.jasper.runtime.PageContextImpl.forward(PageContextImpl.java:680)
at org.apache.jsp.index_jsp._jspService(index_jsp.java:60)
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:388)
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.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:291)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)

感谢您的耐心等待。请告诉我这可能是什么原因。我已经检查了 faces.config 和 beans 以及 jsp 页面等。每件事都绑定(bind)得很好。事实上，它工作得很好，突然生成的这个错误是奇怪和令人毛骨悚然的。

提前致谢。请在结束问题之前回答，或者因为我太天真而对我大喊大叫。

Answer 1

这是在 eclipse 和 tomcat 中部署应用程序的典型问题。 正如shazin所说，你可以做Project-Clean Maven clean等。

这应该足够了，但就我而言，有时这并不能解决问题。

如果它不起作用，请尝试转到“服务器”选项卡，右键单击 tomcat 服务器并执行“清理”。 Tomcat 将再次发布项目。