Tracking previous page in JSF

I want to find out the previous page from where the current page is called. Based on the previous page I want to enable or disable a particular component. Can anybody h开发者_StackOverflow社区elp me in this regard.

Depends on the concrete functional requirement which isn't entirely clear from your question. You could pass an unique request parameter. E.g. when it concerns a GET link:

<h:link value="Next" outcome="next">
    <f:param name="foo" value="bar" />
</h:link>

or a POST link:

<h:form>
    <h:commandLink value="Next" action="next">
        <f:param name="foo" value="bar" />
    </h:commandLink>
</h:form>

with in next.xhtml

<h:someComponent rendered="#{param.foo == 'bar'}">
    ...
</h:someComponent>

or if you don't care about the param's value:

<h:someComponent rendered="#{not empty param.foo}">
    ...
</h:someComponent>

An alternative which can be much better if you don't want to allow the enduser being able to manipulate the request is to set a bean property during a POST action and then return to the next view:

<h:form>
    <h:commandLink value="Next" action="#{bean.next}" />
</h:form>

with e.g.

public String next() {
    foo = "bar";
    return "next";
}

and in next.xhtml

<h:someComponent rendered="#{bean.foo == 'bar'}">
    ...
</h:someComponent>