    public Response all() {
        List<Hotel> hotels = new ArrayList<Hotel>();
        for (HotelProvider provider : providers) {
            hotels.addAll(provider.hotels());
        }
        if (app.isValid()) {
            return Render.view("hotel/all.xhtml", getClass())
                    .param("hotels", hotels)
                    .param("providers", providers)
                    .render();
        } else {
            return Render.view("hotel/none.xhtml", getClass())
                    .param("hotels", hotels)
                    .param("providers", providers).render();
        }
    }

    public Response all() {
        List<Hotel> hotels = new ArrayList<Hotel>();
        for (HotelProvider provider : providers) {
            hotels.addAll(provider.hotels());
        }
        if (app.isValid()) {
            return Render.view("hotel/all.xhtml", getClass())
                    .param("hotels", hotels)
                    .param("providers", providers)
                    .render();
        } else {
            return Render.view("hotel/none.xhtml", getClass())
                    .param("hotels", hotels)
                    .param("providers", providers)
                    .render();
        }
    }
