@Bean
    public Filter etagFilter() {
        return new ShallowEtagHeaderFilter();
    }

@Bean
public FilterRegistrationBean<ShallowEtagHeaderFilter> etagFilter() {
    FilterRegistrationBean<ShallowEtagHeaderFilter> registration = new FilterRegistrationBean<>(new ShallowEtagHeaderFilter());
    registration.setDispatcherTypes(EnumSet.of(DispatcherType.REQUEST, DispatcherType.ASYNC));
    return registration;
}