* Checks if a permission string is a user permission.
     *
     * @param permission The permission string.
     * @return true if it is a user permission, false otherwise.
     */
    public boolean isUserPermission(final String permission) {
        if (StringUtil.isNotBlank(permission)) {
            return permission.startsWith(ComponentUtil.getFessConfig().getRoleSearchUserPrefix());
        }
        return false;
    }