MyExceptionMapper

public Response toResponse(WebApplicationException ex) {
        Response r = ex.getResponse();
        if (r.getStatus() == 403 && r.getEntity() == null) {
            return Response.fromResponse(r).entity(new Viewable("/error-pages/403", null)).build();
        }
        else if (r.getStatus() == 404 && r.getEntity() == null) {
            return Response.ok(new Viewable("/error-pages/404", null)).build();
//            return Response.fromResponse(r).entity(new Viewable("/error-pages/404", null)).build();
        }
        else return r;

    }