String url = DocumentUtil.getValue(document, fessConfig.getIndexFieldUrl(), String.class);

        if (StringUtil.isBlank(url)) {
            return "#not-found-" + DocumentUtil.getValue(document, fessConfig.getIndexFieldDocId(), String.class);
        }

        final boolean isSmbUrl = url.startsWith("smb:") || url.startsWith("smb1:");
        final boolean isFtpUrl = url.startsWith("ftp:");

     * Get the value for the key 'index.field.doc_id'. <br>
     * The value is, e.g. doc_id <br>
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getIndexFieldDocId();

    /**
     * Get the value for the key 'index.field.id'. <br>
     * The value is, e.g. _id <br>
     * @return The value of found property. (NotNull: if not found, exception but basically no way)