title: java.lang.NullPointerException at com.sun.faces.context.flash.ELFlash.loggingGetPhaseMapForReading
body: <p>I am running my application in apache-tomcat-7.0.16 using JSF-2.1.2. After adding navigation rules in faces-config.xml, I am getting the NullPointerException. This bug was filed in JSF forum. Is there any compatible version between JSF and the tomcat app server or any solution for this? Error stack trace is given below:</p>
  
  <pre><code>java.lang.NullPointerException
      at com.sun.faces.context.flash.ELFlash.loggingGetPhaseMapForReading(ELFlash.java:793)
      at com.sun.faces.context.flash.ELFlash.getPhaseMapForReading(ELFlash.java:826)
      at com.sun.faces.context.flash.ELFlash.isEmpty(ELFlash.java:484)
      at com.sun.faces.facelets.util.DevTools.writeVariables(DevTools.java:325)
      at com.sun.faces.facelets.util.DevTools.writeVariables(DevTools.java:215)
      at com.sun.faces.facelets.util.DevTools.debugHtml(DevTools.java:130)
      at com.sun.faces.renderkit.RenderKitUtils.renderHtmlErrorPage(RenderKitUtils.java:1159)
      at com.sun.faces.context.ExceptionHandlerImpl.throwIt(ExceptionHandlerImpl.java:269)
      at com.sun.faces.context.ExceptionHandlerImpl.handle(ExceptionHandlerImpl.java:141)
      at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:119)
      at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
      at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
      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 com.sun.faces.context.ExternalContextImpl.dispatch(ExternalContextImpl.java:546)
      at com.sun.faces.application.view.JspViewHandlingStrategy.executePageToBuildView(JspViewHandlingStrategy.java:364)
      at com.sun.faces.application.view.JspViewHandlingStrategy.buildView(JspViewHandlingStrategy.java:154)
      at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:100)
      at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
      at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
      at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
      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: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:662)
  </code></pre>