final String[] toAddresses = form.notificationTo.split(",");
        final Map<String, Object> dataMap = new HashMap<>();
        dataMap.put("hostname", systemHelper.getHostname());

        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final Postbox postbox = ComponentUtil.getComponent(Postbox.class);
        try {

        shutdownHookList.add(hook);
    }

    /**
     * Gets the hostname of the local machine.
     *
     * @return The hostname.
     */
    public String getHostname() {
        final Map<String, String> env = getEnvMap();
        if (env.containsKey("COMPUTERNAME")) {
            return env.get("COMPUTERNAME");
        }
        if (env.containsKey("HOSTNAME")) {