One possible reason why you are having problems in a @PostConstruct method is, that Rewrite by default does injection of parameters very early in request processing. Actually before the JSF lifecycle starts. So it is possible that your bean is created outside of the JSF lifecycle and therefore using a NavigationHandler won’t work. You can work around that by deferring the parameter injection (see “Path Parameters” in the migration guide).
In your ExceptionHandler you could use the standard Servlet API for your redirect instead. This is IMHO even simpler than using a NavigatonHandler.
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