### Question:
CommMentionParser extends PlainTextDataFileParser<List<CommMention>> { public static CommMentionParser getDefault() { return INSTANCE; } private  CommMentionParser(); static CommMentionParser getDefault();  }### Answer:
@Test public void test() throws IOException { final String basePath = System.getenv("DATA_DIR"); if (isNullOrEmpty(basePath)) { LOGGER.warn("To run this test, you need to set a system variable named DATA_DIR to the dir contains the data files."); return; } final Optional<Path> dataFile = Files .list(Paths.get(basePath)) .filter(path -> COMM_MENTIONS_TSV.equals(path.getFileName().toString())) .findFirst(); if (!dataFile.isPresent()) { LOGGER.warn("No {} found under {}, skipping ...", COMM_MENTIONS_TSV, basePath); return; } ReportDetails<List<CommMention>> commMentionsReport = CommMentionParser.getDefault().parse(dataFile.get()); assertNotNull(commMentionsReport); assertTrue(commMentionsReport.getError(), commMentionsReport.isOk()); final List<CommMention> mentions = commMentionsReport.getData(); assertNotNull(mentions); assertFalse(mentions.isEmpty()); LOGGER.info(JsonUtil.toPrettyJson(mentions)); }