* Even if empty string, treated as empty plainly. So "IF pmb != null" is false if empty.
     * @param details The parameter value of details. (NotNull)
     */
    public void setDetails(String details) {
        registerVariable("details", details);
    }

                    postcard.setCount(String.valueOf(levelEvents.size()));
                    postcard.setInterval(String.valueOf(fessConfig.getLogNotificationIntervalAsInteger()));
                    postcard.setDetails(details);
                });
            } catch (final Exception e) {
                logger.warn("Failed to send log notification.", e);
            } finally {