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

    /**
     * Get the value for the key 'online.help.base.link'. <br>
     * The value is, e.g. https://fess.codelibs.org/{lang}/{version}/admin/ <br>
     * comment: Base link for online help.