public String getAuthcScheme() {
        return authcScheme;
    }
Returns the HTTP <b><code>WWW-Authenticate</code></b> header scheme that this filter will use when sending
the HTTP Basic challenge response.  The default value is <code>BASIC</code>.

@return the HTTP <code>WWW-Authenticate</code> header scheme that this filter will use when sending the HTTP
Basic challenge response.
@see #sendChallenge
web/src/main/java/org/apache/shiro/web/filter/authc/HttpAuthenticationFilter.java