private static int order(Method method) {
        final Order order = AnnotationUtil.findFirst(method, Order.class);
        return order != null ? order.value() : 0;
    }
Returns the value of the order of the {@link Method}. The order could be retrieved from {@link Order}
annotation. 0 would be returned if there is no specified {@link Order} annotation.
core/src/main/java/com/linecorp/armeria/internal/server/annotation/AnnotatedServiceFactory.java