Get Cookies from ServletRequest
I'm using ServletRequest开发者_StackOverflowListener
to attach to new requests, get a ServletRequest
object and extract cookies from it.
I've noticed that only HTTPServletRequest
has cookies but I haven't found a connection between those two objects.
Is it okay to use
HttpServletRequest request = ((HttpServletRequest) FacesContext.getCurrentInstance()
.getExternalContext().getRequest());
to retrieve the request while in a RequestInitialized
method? (I do want to run on every request)
FYI - This is all done in a JSF 1.2 Application
This is not correct. The FacesContext
isn't available in a ServletRequestListener
per se. The getCurrentInstance()
might return null
, leading to NPE's.
If you're running the webapp on a HTTP webserver (and thus not some Portlet webserver for example), you could just cast the ServletRequest
to HttpServletRequest
.
public void requestInitialized(ServletRequestEvent event) {
HttpServletRequest request = (HttpServletRequest) event.getServletRequest();
// ...
}
Note that a more common practice is to use a Filter
for this since you can map this on a fixed URL pattern like *.jsf
or even on specific servlets so that it runs only when the FacesServlet
runs. You might for example want to skip cookie checks on static resources like CSS/JS/images.
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) {
HttpServletRequest request = (HttpServletRequest) req;
// ...
chain.doFilter(req, res);
}
When you happens to be already inside the JSF context (in a managed bean, phaselistener or whatever), you could just use ExternalContext#getRequestCookieMap()
to get the cookies.
Map<String, Object> cookies = externalContext.getRequestCookieMap();
// ...
When running JSF on top of Servlet API, the map value is of type javax.servlet.http.Cookie
.
Cookie cookie = (Cookie) cookies.get("name");
Yes, you can do that. In Web scenarios, this will always be ok. If you want to be sure, you could do a check for the type first. (Good practice anyway):
if (FacesContext.getCurrentInstance().getExternalContext().getRequest() instanceof HttpServletRequest) {
...
By the way: Why do you have to use FacesContext
? From where are you calling this code?
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