Back Navigation and Browser Buttons

Question

What is the best way to implement back navigation in JSF, such that the application also behaves as expected when the user sometimes uses the browser's back button?
Say, we have a page "index.jsp" and a page "results.jsp". From both pages it should be possible to navigate to the page "help.jsp" (which contains a back button). From "help.jsp" it might be possible to further navigate to, say, "about.jsp" (which also contains a back button and is, for example, also accessible directely from "index.jsp").
After the sequence "index->help->about", the user expects to be at "index" again after clicking back on about.jsp and then clicking back on help.jsp. If the same sequence starts at "results.jsp", the user would expect to be at "results.jsp" after clicking the two back buttons, etc.
What is the best way to achieve this behaviour? I guess I best store the entire navigation history in a session bean (something like a stack or so). Is that a good idea? I wonder how I best treat the case when the user hits the browser's back button (for example to navigate back from about.jsp to help.jsp). Any ideas? I could imagine that I could send a unique id (e.g. an increasing counter, or a long random variable) for every button click (using a hidden input, maybe?), such that I can always find the right point again in my navigation stack. But how would I nicely integrate something like this in JSF?
Thanks for any hints!
Michael

Answer 1

This one is nice. But it doesn't redirect to a GET-formed URL.
I just had taken 20 mins to refine it:
test.jsp<h:form>
    <h:inputText id="paramname1" value="#{myBean.paramname1}" />
    <h:inputText id="paramname2" value="#{myBean.paramname2}" />
    <h:commandButton value="submit" action="#{myBean.action}" />
</h:form>MyBeanpublic class MyBean {
    private String paramname1;
    private String paramname2;
    // + getters + setters
    public void action() {
        System.out.println("meep");
}faces-config.xml<lifecycle>
    <phase-listener>mypackage.PostRedirectGetListener</phase-listener>
</lifecycle>
<managed-bean>
    <managed-bean-name>myBean</managed-bean-name>
    <managed-bean-class>mypackage.MyBean</managed-bean-class>
    <managed-bean-scope>request</managed-bean-scope>
    <managed-property>
        <property-name>paramname1</property-name>
        <value>#{param.paramname1}</value>
    </managed-property>
    <managed-property>
        <property-name>paramname2</property-name>
        <value>#{param.paramname2}</value>
    </managed-property>
</managed-bean>PostRedirectGetListenerpublic void beforePhase(PhaseEvent event) {
    if (event.getPhaseId() == PhaseId.RENDER_RESPONSE) {
        FacesContext facesContext = event.getFacesContext();
        HttpServletRequest request = (HttpServletRequest) facesContext.getExternalContext().getRequest();
        if ("POST".equals(request.getMethod())) {
            Set paramKeys = facesContext.getExternalContext().getRequestParameterMap().keySet();
            List params = new ArrayList();
            for (Iterator it = paramKeys.iterator(); it.hasNext();) {
                String componentId = (String) it.next();
                UIComponent component = facesContext.getViewRoot().findComponent(componentId);
                if (component instanceof UIInput) {
                    String paramname = componentId.substring(componentId.lastIndexOf(':') + 1);
                    Object value = ((UIInput) component).getValue();
                    String paramvalue = value != null ? value.toString() : "";
                    params.add(paramname + "=" + paramvalue);
            String url = facesContext.getApplication().getViewHandler().getActionURL(
                facesContext, facesContext.getViewRoot().getViewId());
            for (int i = 0; i < params.size(); i++) {
                switch (i) {
                    case 0: url += "?" + params.get(i); break;
                    default: url += "&" + params.get(i); break;
            try {
                System.out.println("PRG to " + url);
                event.getFacesContext().getExternalContext().redirect(url);
            } catch (IOException e) {
                e.printStackTrace();
public void afterPhase(PhaseEvent event) {
    // Do nothing.
public PhaseId getPhaseId() {
    return PhaseId.ANY_PHASE;
}For restoring facesmessages, just add the relevant code of the PRG thingy you have found.