### Question:
PaperDataServiceImpl implements PaperDataService { @Override public List<PaperFullData> getFullDataByIds(List<Long> paperIds, boolean isDeep) { if (paperIds.size() <= 0) { return null; } Map<Long, Paper> paperIdPaperMap = getPaperIdPaperMap(paperIds); Map<Long, List<Tag>> paperIdTagMap = getPaperIdTagMap(paperIds); Map<Long, Map<Integer, Long>> paperIdSerialProblemIdMap = getPaperIdSerialProblemIdMap(paperIds); Map<Long, List<ProblemFullData>> paperIdProblemFullDataMap = null; if (isDeep) { paperIdProblemFullDataMap = getPaperIdProblemFullDataMap(paperIdSerialProblemIdMap); } List<PaperFullData> paperFullDataList = new ArrayList<>(); for (Long paperId : paperIds) { PaperFullData paperFullData = new PaperFullData(); paperFullData.setDeep(isDeep); paperFullData.setTags(paperIdTagMap.get(paperId)); paperFullData.setPaper(paperIdPaperMap.get(paperId)); paperFullData.setSerialProblemIdMap(paperIdSerialProblemIdMap.get(paperId)); if (isDeep) { paperFullData.setProblems(paperIdProblemFullDataMap.get(paperId)); } paperFullDataList.add(paperFullData); } return paperFullDataList; }  @Override List<PaperFullData> getFullDataByIds(List<Long> paperIds, boolean isDeep); Map<Long, Paper> getPaperIdPaperMap(List<Long> paperIds); Map<Long, List<Tag>> getPaperIdTagMap(List<Long> paperIds); Map<Long, Map<Integer, Long>> getPaperIdSerialProblemIdMap(List<Long> paperIds); Map<Long, List<ProblemFullData>> getPaperIdProblemFullDataMap(Map<Long, Map<Integer, Long>> paperIdSerialProblemIdMap);  }### Answer:
@Test public void test() { ArrayList<Long> longs = new ArrayList<>(); longs.add(100L); List<PaperFullData> fullDataByIds = paperDataServiceImpl.getFullDataByIds(longs, true); System.out.println("--------------------------------------"); System.out.println(fullDataByIds); System.out.println("--------------------------------------"); }