httpResponse.addHeader(ACCESS_CONTROL_ALLOW_HEADERS, fessConfig.getApiCorsAllowHeaders());
        httpResponse.addHeader(ACCESS_CONTROL_MAX_AGE, fessConfig.getApiCorsMaxAge());
        httpResponse.addHeader(ACCESS_CONTROL_ALLOW_CREDENTIALS, fessConfig.getApiCorsAllowCredentials());
    }

     * The value is, e.g. 3600 <br>
     * comment: Max age for CORS preflight requests.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getApiCorsMaxAge();

    /**
     * Get the value for the key 'api.cors.max.age' as {@link Integer}. <br>
     * The value is, e.g. 3600 <br>
     * comment: Max age for CORS preflight requests.