Spring Digest身份验证错误筛选器错误

Question

addFilter(getDigestAuthFilter())引发错误，说使getDigestAuthFilter函数返回javax.servlet.Filter而不是DigestAuthenticationFilter。救命！！！

private DigestAuthenticationFilter getDigestAuthFilter() throws Exception {
    DigestAuthenticationFilter digestFilter = new DigestAuthenticationFilter();

    digestFilter.setUserDetailsService(userDetailsServiceBean());


    digestFilter.setAuthenticationEntryPoint(getDigestEntryPoint());
    return digestFilter;
}



@Override
protected void configure(HttpSecurity http) throws Exception {

    http.antMatcher("/hello/**").  // this filter chain is matching this pattern of request;
            addFilter(getDigestAuthFilter()). // add this new filter to the existing chain of filters;
            exceptionHandling().authenticationEntryPoint(getDigestEntryPoint()) // when exception occurs auto route to this entrypoint which will give out headers;
            .and().authorizeRequests().antMatchers("/hello/**").hasAnyRole("ADMIN","USER");
}