jsf 2 - Redirect before loading the page in JSF2 -

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• hit bean method , redirect on request 1 answer

i have requirement before page going load want check whether query string exists or not if query string exists want redirect page instead of current page how can handle type of requirement in jsf 2.

thanks in advance

when on jsf 2.2, can use <f:viewaction> this.

<f:metadata>     <f:viewparam name="paramname" value="#{bean.paramname}" />     <f:viewaction action="#{bean.check}" /> </f:metadata> 

(paramname name of query string parameter)

private string paramname; // +getter+setter  public string check() {     if (paramname == null) {         return "error.xhtml";     }      return null; } 

when not on jsf 2.2 yet (jsf 2.0/2.1), can use <f:event type="prerenderview"> this.

<f:metadata>     <f:viewparam name="paramname" value="#{bean.paramname}" />     <f:event type="prerenderview" listener="#{bean.check}" /> </f:metadata> 

private string paramname; // +getter+setter  public void check() throws ioexception {     if (paramname == null) {         facescontext.getcurrentinstance().getexternalcontext().redirect("error.xhtml");     } } 

see also:

• what can <f:metadata>, <f:viewparam> , <f:viewaction> used for?