No active FlowSession to access; this FlowExecution has ended

单点登录，即使登录成功，验证通过还是会报如下错误，为什么，那位大仙知道？

[0729 15:55:58 270 DEBUG] [[ACTIVE] ExecuteThread: '1' for queue: 'weblogic.kernel.Default (self-tuning)'] TerminateWebSessionListener.sessionStarted_aroundBody0(64) | Error getting service from flow state.

java.lang.IllegalStateException: No active FlowSession to access; this FlowExecution has ended

at org.springframework.webflow.engine.impl.FlowExecutionImpl.getActiveSession(FlowExecutionImpl.java:191)

at org.springframework.webflow.engine.impl.RequestControlContextImpl.getFlowScope(RequestControlContextImpl.java:134)

at org.jasig.cas.web.support.WebUtils.getService_aroundBody8(WebUtils.java:87)

at org.jasig.cas.web.support.WebUtils.getService_aroundBody9$advice(WebUtils.java:57)

at org.jasig.cas.web.support.WebUtils.getService(WebUtils.java:1)

at org.jasig.cas.web.flow.TerminateWebSessionListener.sessionStarted_aroundBody0(TerminateWebSessionListener.java:62)

at org.jasig.cas.web.flow.TerminateWebSessionListener.sessionStarted_aroundBody1$advice(TerminateWebSessionListener.java:57)

at org.jasig.cas.web.flow.TerminateWebSessionListener.sessionStarted(TerminateWebSessionListener.java:1)

at org.springframework.webflow.engine.impl.FlowExecutionListeners.fireSessionStarted(FlowExecutionListeners.java:126)

at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:368)

at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:225)

at org.springframework.webflow.executor.FlowExecutorImpl.launchExecution(FlowExecutorImpl.java:141)

at org.springframework.webflow.mvc.servlet.FlowHandlerAdapter.handle(FlowHandlerAdapter.java:193)

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)

at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:779)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:821)

at org.jasig.cas.web.init.SafeDispatcherServlet.service_aroundBody2(SafeDispatcherServlet.java:128)

at org.jasig.cas.web.init.SafeDispatcherServlet.service_aroundBody3$advice(SafeDispatcherServlet.java:57)

at org.jasig.cas.web.init.SafeDispatcherServlet.service(SafeDispatcherServlet.java:1)

at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)

at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:125)

at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:301)

at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:27)

at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:57)

at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:89)

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)

at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:347)

at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:260)

at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:57)

at com.github.inspektr.common.web.ClientInfoThreadLocalFilter.doFilter(ClientInfoThreadLocalFilter.java:63)

at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:57)

at weblogic.servlet.internal.RequestEventsFilter.doFilter(RequestEventsFilter.java:27)

at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:57)

at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3730)

at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3696)

at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)

at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120)

at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2273)

at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2179)

at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1490)

at weblogic.work.ExecuteThread.execute(ExecuteThread.java:256)

at weblogic.work.ExecuteThread.run(ExecuteThread.java:221)