jsf-2 - RichFaces 中的 session 空指针-6ren

jsf-2 - RichFaces 中的 session 空指针

转载作者：行者123 更新时间：2023-12-05 00:00:40

全部，

我在尝试访问 session map 时遇到以下问题:

FacesContext.getCurrentInstance().getExternalContext() 
        .getSessionMap().put("userSession", session);

我在登录时看到此错误，然后等待几分钟，然后单击访问 bean 的任何按钮。这是在超时之前(我设置为 60 分钟)。有人可以帮忙吗？这对我来说是一个主要的节目阻止者......

java.lang.NullPointerException
      at com.sun.faces.context.SessionMap.put(ExternalContextImpl.java:970)
      at com.mounza.common.Util.logUser(Util.java:129)
      at com.mounza.common.Util.userStart(Util.java:159)
      at com.mounza.homepage.UserHomepageAction.<init>(UserHomepageAction.java:39)
      at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
      at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
      at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
      at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
      at java.lang.Class.newInstance0(Class.java:355)
      at java.lang.Class.newInstance(Class.java:308)
      at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:186)
      at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:106)
      at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:368)
      at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:230)
      at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:86)
      at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54)
      at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:72)
      at org.apache.el.parser.AstIdentifier.getValue(AstIdentifier.java:69)
      at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
      at com.sun.faces.application.ValueBindingValueExpressionAdapter.getValue(ValueBindingValueExpressionAdapter.java:113)
      at org.ajax4jsf.taglib.html.facelets.KeepAliveHandler.apply(KeepAliveHandler.java:76)
      at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
      at com.sun.facelets.tag.jsf.ComponentHandler.applyNextHandler(ComponentHandler.java:314)
      at com.sun.facelets.tag.jsf.ComponentHandler.apply(ComponentHandler.java:169)
      at com.sun.facelets.tag.jsf.core.ViewHandler.apply(ViewHandler.java:109)
      at com.sun.facelets.tag.ui.DefineHandler.applyDefinition(DefineHandler.java:64)
      at com.sun.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:131)
      at com.sun.facelets.impl.DefaultFaceletContext$TemplateManager.apply(DefaultFaceletContext.java:337)
      at com.sun.facelets.impl.DefaultFaceletContext.includeDefinition(DefaultFaceletContext.java:307)
      at com.sun.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:68)
      at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
      at com.sun.facelets.tag.jsf.core.ViewHandler.apply(ViewHandler.java:109)
      at com.sun.facelets.tag.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:47)
      at com.sun.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:119)
      at com.sun.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:49)
      at com.sun.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:25)
      at com.sun.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:248)
      at com.sun.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:294)
      at com.sun.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:273)
      at com.sun.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:140)
      at com.sun.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:113)
      at com.sun.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:49)
      at com.sun.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:25)
      at com.sun.facelets.impl.DefaultFacelet.apply(DefaultFacelet.java:95)
      at com.sun.facelets.FaceletViewHandler.buildView(FaceletViewHandler.java:524)
      at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:567)
      at org.ajax4jsf.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:100)
      at org.ajax4jsf.application.AjaxViewHandler.renderView(AjaxViewHandler.java:176)
      at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:110)
      at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:100)
      at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
      at javax.faces.webapp.FacesServlet.service(FacesServlet.java:266)
      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:349)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
      at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:206)
      at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:290)
      at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:388)
      at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:515)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:369)
      at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
      at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:100)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:187)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
      at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:168)
      at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
      at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
      at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
      at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
      at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
      at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
      at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
      at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
      at java.lang.Thread.run(Thread.java:680)

[编辑]
我有一种感觉，这可能与使用 Spring Web 安全进行登录/注销有关。有没有其他人在使用 spring 时看到过类似的东西？

[编辑 2]
我从头开始重建项目，我收到一个新错误，但同样的问题，如果有人知道:

SEVERE: java.lang.NullPointerException
javax.faces.el.EvaluationException: java.lang.NullPointerException
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102)
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
    at javax.faces.component.UICommand.broadcast(UICommand.java:387)
    at org.ajax4jsf.component.AjaxViewRoot.processEvents(AjaxViewRoot.java:329)
    at org.ajax4jsf.component.AjaxViewRoot.broadcastEventsForPhase(AjaxViewRoot.java:304)
    at org.ajax4jsf.component.AjaxViewRoot.processPhase(AjaxViewRoot.java:261)
    at org.ajax4jsf.component.AjaxViewRoot.processApplication(AjaxViewRoot.java:474)
    at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:82)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:100)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:265)
    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:349)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:206)
    at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:290)
    at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:388)
    at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:515)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:369)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:100)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:187)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:381)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:168)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
    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:293)
    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(Thread.java:680)
Caused by: java.lang.NullPointerException
    at org.apache.catalina.connector.Request.parseParameters(Request.java:2599)
    at org.apache.catalina.connector.Request.getParameter(Request.java:1106)
    at org.apache.catalina.connector.RequestFacade.getParameter(RequestFacade.java:355)
    at javax.servlet.ServletRequestWrapper.getParameter(ServletRequestWrapper.java:158)
    at javax.servlet.ServletRequestWrapper.getParameter(ServletRequestWrapper.java:158)
    at com.sun.faces.context.RequestParameterMap.get(ExternalContextImpl.java:1152)
    at com.sun.faces.context.RequestParameterMap.get(ExternalContextImpl.java:1140)
    at java.util.Collections$UnmodifiableMap.get(Collections.java:1282)
    at com.mounza.homepage.UserHomepageAction.update(UserHomepageAction.java:47)
    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:597)
    at org.apache.el.parser.AstValue.invoke(AstValue.java:191)
    at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276)
    at com.sun.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:68)
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
    ... 56 more

最佳答案

这是根本原因的相关部分:

Caused by: java.lang.NullPointerException
    at org.apache.catalina.connector.Request.parseParameters(Request.java:2599)
    at org.apache.catalina.connector.Request.getParameter(Request.java:1106)
    at org.apache.catalina.connector.RequestFacade.getParameter(RequestFacade.java:355)
    at javax.servlet.ServletRequestWrapper.getParameter(ServletRequestWrapper.java:158)
    at javax.servlet.ServletRequestWrapper.getParameter(ServletRequestWrapper.java:158)
    at com.sun.faces.context.RequestParameterMap.get(ExternalContextImpl.java:1152)
    at com.sun.faces.context.RequestParameterMap.get(ExternalContextImpl.java:1140)
    at java.util.Collections$UnmodifiableMap.get(Collections.java:1282)
    at com.mounza.homepage.UserHomepageAction.update(UserHomepageAction.java:47)
    ...

此异常表示 HTTP 请求已过期/回收。我在你的代码中没有看到任何东西，但是这个异常反过来表明你得到了一个 FacesContext 的实例。 , 或 ExternalContext ，或由 ExternalContext#getRequestParameterMap() 返回的 map 作为托管 bean 的类变量，它的范围比请求范围更广，如下所示:

@ManagedBean
@ViewScoped // Or @SessionScoped or @ApplicationScoped
public class UserHomepageAction {

    private Map<String, String> params;

    public UserHomepageAction() {
        params = FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap();
    }

    public void update() {
        String value = params.get(name); // Fail!!
        // ...
    }

}

您应该从不去做。 bean 的生命周期跨越多个 HTTP 请求。在与构建 bean 不同的 HTTP 请求期间调用 bean 的 action 方法。您应该改为在方法局部范围内获取线程/请求局部变量:

    public void update() {
        Map<String, String> params = FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap();
        String value = params.get(name); // OK!!
        // ...
    }

无关到具体问题:像那样摆弄请求参数映射是一种味道。你看了吗 <f:viewParam> ?另见 What can <f:metadata>, <f:viewParam> and <f:viewAction> be used for? .

关于jsf-2 - RichFaces 中的 session 空指针，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/9787578/

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jsf-2 - RichFaces 中的 session 空指针