Cannot forward a response that is already committed exeption after Log out

Question

Hello,
I am using Jdeveloper 11.1.1.3.0, ADF DC, ADF Faces, ADF security.
I have a logout button in my template, and I want the user to go back to login page (login.html; which was generated automaticlly when you use ADF security) after successful Log out.
here is my logout method
    public String doLogOut() throws IOException {
        // Add event code here...
        ExternalContext ectx =
            FacesContext.getCurrentInstance().getExternalContext();
        HttpServletResponse response = (HttpServletResponse)ectx.getResponse();
        HttpSession session = (HttpSession)ectx.getSession(false);
        session.invalidate();
        response.sendRedirect("login.html");
        return null;      
    }when I click the log out button, every thing seems ok, and the user redirected to login.html page. However, I see the following Exception in Jdeveloper Log window.
<Jan 4, 2012 12:16:31 PM EET> <Error> <HTTP> <BEA-101020> <[ServletContext@19059163[app:CTP-New module:CTP-New-ViewController-context-root path:/CTP-New-ViewController-context-root spec-version:2.5 version:V2.0]] Servlet failed with Exception
java.lang.IllegalStateException: Cannot forward a response that is already committed
     at weblogic.servlet.internal.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:122)
     at com.sun.faces.context.ExternalContextImpl.dispatch(ExternalContextImpl.java:410)
     at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:44)
     at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:44)
     at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:44)
     Truncated. see log file for complete stacktrace
>
<Jan 4, 2012 12:16:31 PM EET> <Notice> <Diagnostics> <BEA-320068> <Watch 'UncheckedException' with severity 'Notice' on server 'DefaultServer' has triggered at Jan 4, 2012 12:16:31 PM EET. Notification details:
WatchRuleType: Log
WatchRule: (SEVERITY = 'Error') AND ((MSGID = 'BEA-101020') OR (MSGID = 'BEA-101017') OR (MSGID = 'BEA-000802'))
WatchData: DATE = Jan 4, 2012 12:16:31 PM EET SERVER = DefaultServer MESSAGE = [ServletContext@19059163[app:CTP-New module:CTP-New-ViewController-context-root path:/CTP-New-ViewController-context-root spec-version:2.5 version:V2.0]] Servlet failed with Exception
java.lang.IllegalStateException: Cannot forward a response that is already committed
     at weblogic.servlet.internal.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:122)
     at com.sun.faces.context.ExternalContextImpl.dispatch(ExternalContextImpl.java:410)
     at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:44)
     at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:44)
     at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:44)
     at org.apache.myfaces.trinidad.context.ExternalContextDecorator.dispatch(ExternalContextDecorator.java:44)
     at org.apache.myfaces.trinidadinternal.context.FacesContextFactoryImpl$OverrideDispatch.dispatch(FacesContextFactoryImpl.java:267)
     at com.sun.faces.application.ViewHandlerImpl.executePageToBuildView(ViewHandlerImpl.java:473)
     at com.sun.faces.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:141)
     at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:189)
     at org.apache.myfaces.trinidadinternal.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:193)
     at oracle.adfinternal.view.faces.lifecycle.LifecycleImpl._renderResponse(LifecycleImpl.java:710)
     at oracle.adfinternal.view.faces.lifecycle.LifecycleImpl._executePhase(LifecycleImpl.java:273)
     at oracle.adfinternal.view.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:205)
     at javax.faces.webapp.FacesServlet.service(FacesServlet.java:266)
     at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)
     at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:125)
     at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:300)
     at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:26)
     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
     at oracle.adf.model.servlet.ADFBindingFilter.doFilter(ADFBindingFilter.java:191)
     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
     at oracle.adfinternal.view.faces.webapp.rich.RegistrationFilter.doFilter(RegistrationFilter.java:97)
     at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl$FilterListChain.doFilter(TrinidadFilterImpl.java:420)
     at oracle.adfinternal.view.faces.activedata.AdsFilter.doFilter(AdsFilter.java:60)
     at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl$FilterListChain.doFilter(TrinidadFilterImpl.java:420)
     at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl._doFilterImpl(TrinidadFilterImpl.java:247)
     at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl.doFilter(TrinidadFilterImpl.java:157)
     at org.apache.myfaces.trinidad.webapp.TrinidadFilter.doFilter(TrinidadFilter.java:92)
     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
     at oracle.security.jps.ee.http.JpsAbsFilter$1.run(JpsAbsFilter.java:94)
     at java.security.AccessController.doPrivileged(Native Method)
     at oracle.security.jps.util.JpsSubject.doAsPrivileged(JpsSubject.java:313)
     at oracle.security.jps.ee.util.JpsPlatformUtil.runJaasMode(JpsPlatformUtil.java:414)
     at oracle.security.jps.ee.http.JpsAbsFilter.doFilter(JpsAbsFilter.java:138)
     at oracle.security.jps.ee.http.JpsFilter.doFilter(JpsFilter.java:71)
     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
     at oracle.dms.wls.DMSServletFilter.doFilter(DMSServletFilter.java:330)
     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
     at weblogic.servlet.internal.RequestEventsFilter.doFilter(RequestEventsFilter.java:27)
     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
     at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.doIt(WebAppServletContext.java:3684)
     at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3650)
     at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
     at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:121)
     at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2268)
     at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2174)
     at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1446)
     at weblogic.work.ExecuteThread.execute(ExecuteThread.java:201)
     at weblogic.work.ExecuteThread.run(ExecuteThread.java:173)
SUBSYSTEM = HTTP USERID = <WLS Kernel> SEVERITY = Error THREAD = [ACTIVE] ExecuteThread: '11' for queue: 'weblogic.kernel.Default (self-tuning)' MSGID = BEA-101020 MACHINE = Mjabr-PC TXID =  CONTEXTID = 4b079561b4c220a0:10458ad0:134a7995c3f:-8000-0000000000000241 TIMESTAMP = 1325672191307 
WatchAlarmType: AutomaticReset
WatchAlarmResetPeriod: 30000
>Further more when I try to login again, I get this message in the browser
Error 403--Forbidden
From RFC 2068 Hypertext Transfer Protocol -- HTTP/1.1:
10.4.4 403 Forbidden
The server understood the request, but is refusing to fulfill it. Authorization will not help and the request SHOULD NOT be repeated. If the request method was not HEAD and the server wishes to make public why the request has not been fulfilled, it SHOULD describe the reason for the refusal in the entity. This status code is commonly used when the server does not wish to reveal exactly why the request has been refused, or when no other response is applicable.Any help is highly appreciated.

Answer 1

Thank you ADF7,
I used this method
    public String doLogOut() throws IOException {
        // Add event code here...
        FacesContext ctx = FacesContext.getCurrentInstance();
        HttpServletRequest request =
            (HttpServletRequest)ctx.getExternalContext().getRequest();
        ExternalContext ectx =
            FacesContext.getCurrentInstance().getExternalContext();
        try {
            ectx.redirect(request.getContextPath() +
                          "/login.html");
        } catch (Exception exp) {
            exp.printStackTrace();
        return null;
    }but when I re login again I get the same error in the browser
Error 403--Forbidden
From RFC 2068 Hypertext Transfer Protocol -- HTTP/1.1:
10.4.4 403 Forbidden
The server understood the request, but is refusing to fulfill it. Authorization will not help and the request SHOULD NOT be repeated. If the request method was not HEAD and the server wishes to make public why the request has not been fulfilled, it SHOULD describe the reason for the refusal in the entity. This status code is commonly used when the server does not wish to reveal exactly why the request has been refused, or when no other response is applicable.