### Question:
LoggerUtils { public static List<String> getAppIds(String log, Logger logger) { List<String> appIds = new ArrayList<>(); Matcher matcher = APPLICATION_REGEX.matcher(log); while (matcher.find()) { String appId = matcher.group(); if (!appIds.contains(appId)) { logger.info("find app id: {}", appId); appIds.add(appId); } } return appIds; } private  LoggerUtils(); static String buildTaskId(String affix,
                                     int processDefId,
                                     int processInstId,
                                     int taskId); static List<String> getAppIds(String log, Logger logger); static void logError(Optional<Logger> optionalLogger
            , String error); static void logError(Optional<Logger> optionalLogger
            , Throwable e); static void logError(Optional<Logger> optionalLogger
            , String error, Throwable e); static void logInfo(Optional<Logger> optionalLogger
            , String info); static final String TASK_LOGGER_INFO_PREFIX; static final String TASK_LOGGER_THREAD_NAME; static final String TASK_APPID_LOG_FORMAT; }### Answer:
@Test public void getAppIds() { List<String> appIdList = LoggerUtils.getAppIds("Running job: application_1_1",logger); Assert.assertEquals("application_1_1", appIdList.get(0)); }