public void indexFromDocuments(final Consumer<Boolean> success, final Consumer<Throwable> error) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final long interval = fessConfig.getSuggestUpdateRequestIntervalAsInteger().longValue();
        final int docPerReq = fessConfig.getSuggestUpdateDocPerRequestAsInteger();
        final SystemHelper systemHelper = ComponentUtil.getSystemHelper();

     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     * @throws NumberFormatException When the property is not integer.
     */
    Integer getSuggestUpdateRequestIntervalAsInteger();

    /**
     * Get the value for the key 'suggest.update.doc.per.request'. <br>
     * The value is, e.g. 2 <br>