.setLoggerName("test.logger.sub")
                .setLevel(Level.ERROR)
                .setMessage(new SimpleMessage("test message 1"))
                .build();

        LogEvent event2 = Log4jLogEvent.newBuilder()
                .setLoggerName("another.logger.sub")
                .setLevel(Level.ERROR)
                .setMessage(new SimpleMessage("test message 2"))

    }

    private LogEvent createLogEvent(final Level level, final String loggerName, final String message) {
        return Log4jLogEvent.newBuilder() //
                .setLoggerName(loggerName) //
                .setLevel(level) //
                .setMessage(new SimpleMessage(message)) //
                .setTimeMillis(System.currentTimeMillis()) //
                .build();
    }

    @Test
    public void test_createAppender() {

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

    /**
     * Set the value of hostname, used in parameter comment. <br>

                        postcard.dryrun();
                    }
                    postcard.setHostname(systemHelper.getHostname());
                    postcard.setLevel(level);
                    postcard.setCount(String.valueOf(levelEvents.size()));
                    postcard.setInterval(String.valueOf(fessConfig.getLogNotificationIntervalAsInteger()));

   */
  public void testEmptyServiceManager() {
    Logger logger = Logger.getLogger(ServiceManager.class.getName());
    logger.setLevel(Level.FINEST);
    TestLogHandler logHandler = new TestLogHandler();
    logger.addHandler(logHandler);
    ServiceManager manager = new ServiceManager(Arrays.asList());

   */
  public void testEmptyServiceManager() {
    Logger logger = Logger.getLogger(ServiceManager.class.getName());
    logger.setLevel(Level.FINEST);
    TestLogHandler logHandler = new TestLogHandler();
    logger.addHandler(logHandler);
    ServiceManager manager = new ServiceManager(Arrays.asList());

    queue.addListener(listener, directExecutor());
    queue.enqueue(THROWING_EVENT, "custom-label");

    Logger logger = Logger.getLogger(ListenerCallQueue.class.getName());
    logger.setLevel(Level.SEVERE);
    TestLogHandler logHandler = new TestLogHandler();
    logger.addHandler(logHandler);
    try {
      queue.dispatch();
    } finally {
      logger.removeHandler(logHandler);
    }

    queue.addListener(listener, directExecutor());
    queue.enqueue(THROWING_EVENT, "custom-label");

    Logger logger = Logger.getLogger(ListenerCallQueue.class.getName());
    logger.setLevel(Level.SEVERE);
    TestLogHandler logHandler = new TestLogHandler();
    logger.addHandler(logHandler);
    try {
      queue.dispatch();
    } finally {
      logger.removeHandler(logHandler);
    }

        split(ComponentUtil.getFessConfig().getLoggingAppPackages(), ",")
                .of(stream -> stream.map(String::trim).filter(StringUtil::isNotEmpty).forEach(s -> Configurator.setLevel(s, logLevel)));
    }

    /**
     * Gets the current log level.
     *
     * @return The current log level.
     */
    public String getLogLevel() {

            for (final String excluded : EXCLUDED_LOGGERS) {
                if (loggerName.startsWith(excluded)) {
                    return;
                }
            }
        }

        if (!event.getLevel().isMoreSpecificThan(getEffectiveMinLevel())) {
            return;
        }

        try {
            if (!ComponentUtil.getFessConfig().isLogNotificationEnabled()) {
                return;
            }