参考文章：(327条消息) Excel树状数据绘制导出_excel导出树形结构_Deja-vu xxl的博客-CSDN博客https://blog.csdn.net/weixin_45873182/article/details/120132409?spm=1001.2014.3001.5502

@Overridepublic void exportPlus(String yearMonth, HttpServletRequest request ,HttpServletResponse response) {try {String fileName = "周进度填报.xlsx";ServletOutputStream out = response.getOutputStream();HSSFWorkbook workbook = new HSSFWorkbook();response.setHeader("content-type", "text/plain");response.setHeader("content-type", "application/x-msdownload;");response.setContentType("text/plain; charset=utf-8");response.setHeader("Content-Disposition", "attachment;filename="  +  URLEncoder.encode(fileName, "UTF-8"));String projectId = tokenService.getProjectId(request);List<SysDept> deptIdsByProjectId = sysDeptMapper.getDeptIdsByPeojectId(Long.valueOf(projectId));List<SysDept> collect = deptIdsByProjectId.stream().filter(s -> s.getEmail() == null).collect(Collectors.toList());if(collect.size()>0){for (int i = 0; i <collect.size(); i++) {SysDept sysDept = collect.get(i);String email = sysDept.getEmail();if (email == null){exportPlusByProject(sysDept.getDeptId(),yearMonth,workbook, i, sysDept.getDeptName(), out);}}}//原理就是将所有的数据一起写入，然后再关闭输入流。out = response.getOutputStream();workbook.write(out);out.flush();out.close();} catch (IOException e) {e.printStackTrace();}}public void exportPlusByProject(Long zhgdDeptId,String yearMonth,HSSFWorkbook workbook, int sheetNum,String sheetTitle,String[] headers,List<List<JSONObject>> data,ServletOutputStream out) {try {//存放数据的二维集合，twoDimensional 中每个List是树状结构的一个分支的所有数据List<List<JSONObject>> twoDimensional = new ArrayList<>();//******************************查询正文数据******************************ZhgdWeeklyProgressReport zhgdWeeklyProgressReport = new ZhgdWeeklyProgressReport();zhgdWeeklyProgressReport.setZhgdDeptId(zhgdDeptId);zhgdWeeklyProgressReport.setCurrentDates(yearMonth);ZhgdWeeklyProgressReport zhgdWeeklyProgressReport1 = weeklyProgressReportService.getlastMonthData(zhgdWeeklyProgressReport);String fillingTime1 = zhgdWeeklyProgressReport1.getFillingTime();LambdaQueryWrapper<ZhgdWeeklyProgressReport> ZhgdWeeklyProgressReportWrapper = new LambdaQueryWrapper<>();ZhgdWeeklyProgressReportWrapper.eq(ZhgdWeeklyProgressReport::getZhgdDeptId,zhgdDeptId).eq(ZhgdWeeklyProgressReport::getCurrentDates,yearMonth).eq(ZhgdWeeklyProgressReport::getFillingTime,fillingTime1).eq(ZhgdWeeklyProgressReport::getIsExists,2).orderByAsc(ZhgdWeeklyProgressReport::)//------------------------------静态数据-----------------------------------HashMap<String, Object> stringObjectHashMap0 = new HashMap<>();stringObjectHashMap0.put("dictLabel","施工驻地，工地实验室");stringObjectHashMap0.put("key1","39");stringObjectHashMap0.put("key2","0.65%");stringObjectHashMap0.put("key3","767731.2");stringObjectHashMap0.put("key4","0.23%");HashMap<String, Object> stringObjectHashMap1 = new HashMap<>();stringObjectHashMap1.put("dictLabel","施工驻地，工地实验室");HashMap<String, Object> stringObjectHashMap2 = new HashMap<>();stringObjectHashMap2.put("dictLabel","临时工程与设施");ArrayList<JSONObject> list0 = new ArrayList<>();list0.add(new JSONObject(stringObjectHashMap0));list0.add(new JSONObject(stringObjectHashMap1));list0.add(new JSONObject(stringObjectHashMap2));//---------------------------第二组list----------------------------------HashMap<String, Object> stringObjectHashMap10 = new HashMap<>();stringObjectHashMap10.put("dictLabel","拌合站(处)");stringObjectHashMap10.put("key1","75");stringObjectHashMap10.put("key2","1.24%");stringObjectHashMap10.put("key3","444767731.2");stringObjectHashMap10.put("key4","1.33%");HashMap<String, Object> stringObjectHashMap11 = new HashMap<>();stringObjectHashMap11.put("dictLabel","拌合站(处)");HashMap<String, Object> stringObjectHashMap12 = new HashMap<>();stringObjectHashMap12.put("dictLabel","临时工程与设施");ArrayList<JSONObject> list1 = new ArrayList<>();list1.add(new JSONObject(stringObjectHashMap10));list1.add(new JSONObject(stringObjectHashMap11));list1.add(new JSONObject(stringObjectHashMap12));twoDimensional.add(list0);twoDimensional.add(list1);//------------------------------结束------------------------------------//------------------------------表头-----------------------------------//keys 是表头的字段List<String> keys = new ArrayList<>();//tier 是动态项目清单的总层级Integer tier = 3;//创建对象//创建工作表Sheet sheet = workbook.createSheet();workbook.setSheetName(sheetNum, sheetTitle);sheet.setDefaultColumnWidth(25);short s1  = 2 * 256 ;sheet.setDefaultRowHeight(s1);CellStyle styleTltles = workbook.createCellStyle();styleTltles.setFillForegroundColor(IndexedColors.GREEN.getIndex());styleTltles.setAlignment(HorizontalAlignment.CENTER);styleTltles.setVerticalAlignment(VerticalAlignment.CENTER);//下边框styleTltles.setBorderBottom(BorderStyle.THIN);//左边框styleTltles.setBorderLeft(BorderStyle.THIN);//上边框styleTltles.setBorderTop(BorderStyle.THIN);//右边框styleTltles.setBorderRight(BorderStyle.THIN);//自动换行styleTltles.setWrapText(true);//间隔行加背景setRowBackground(workbook);//columnMap 是一个对象，转换成Json//*****************************下面数据请求数据库***********************LambdaQueryWrapper<ZhgdWeeklyProgressReport> weeklyProgressReportLambdaQueryWrapper = new LambdaQueryWrapper<>();weeklyProgressReportLambdaQueryWrapper.eq(ZhgdWeeklyProgressReport::getCurrentDates,yearMonth).eq(ZhgdWeeklyProgressReport::getZhgdDeptId,zhgdDeptId).groupBy(ZhgdWeeklyProgressReport::getFillingTime).groupBy(ZhgdWeeklyProgressReport::getCreateDatetime).orderByAsc(ZhgdWeeklyProgressReport::getCreateDatetime).select(ZhgdWeeklyProgressReport::getFillingTime);List<ZhgdWeeklyProgressReport> weeklyProgressReportList = weeklyProgressReportService.list(weeklyProgressReportLambdaQueryWrapper);HashMap<String, Object> columnMap = new HashMap<>(5);columnMap.put("单价(元)","单价(元)");keys.add("单价(元)");columnMap.put("总量","总量");keys.add("总量");if (weeklyProgressReportList.size()>0){weeklyProgressReportList.stream().forEach(entity->{String fillingTime = entity.getFillingTime();String s = fillingTime + "日完成工程量";columnMap.put(s,s);keys.add(s);});}columnMap.put("完成工程量合计","完成工程量合计");keys.add("完成工程量合计");if (weeklyProgressReportList.size()>0){weeklyProgressReportList.stream().forEach(entity->{String fillingTime = entity.getFillingTime();String s = fillingTime + "日完成产值（万元）";columnMap.put(s,s);keys.add(s);});}columnMap.put("完成产值（万元）合计","完成产值（万元）合计");keys.add("完成产值（万元）合计");columnMap.put("截止上月累计完成工程量","截止上月累计完成工程量");keys.add("截止上月累计完成工程量");columnMap.put("截止上月累计完成产值","截止上月累计完成产值");keys.add("截止上月累计完成产值");columnMap.put("截止本月累计完成工程量","截止本月累计完成工程量");keys.add("截止本月累计完成工程量");columnMap.put("累计完成总量占比","累计完成总量占比");keys.add("累计完成总量占比");columnMap.put("截止本月累计完成产值（万元）","截止本月累计完成产值（万元）");keys.add("截止本月累计完成产值（万元）");//动态创建首行表头JSONObject topBean = new JSONObject();Row firstRow = sheet.createRow(0);JSONObject cm = new JSONObject(columnMap);for (int i = 0; i < tier+keys.size(); i++) {Cell cell = firstRow.createCell(i);if (i<tier){String s="一";switch (i){case 1 : s="二";break;case 2 : s="三";break;}cell.setCellValue(s+"级分类");}else {cell.setCellValue(cm.getString(keys.get(i - tier)));}}//动态绘制数据，tier是层级数，根据业务最多三级for (int i = 0; i < twoDimensional.size(); i++) {Row row = sheet.createRow(i+1);List<JSONObject> list = twoDimensional.get(i);for (int j = 0; j < keys.size()+tier; j++) {Cell cell = row.createCell(j);if (j<tier){//绘制层级标签if (j==0){JSONObject jsonObject = list.get(tier - 1);cell.setCellValue(jsonObject.getString("dictLabel"));continue;}if (j==1){Map map = list.get(tier - 2);cell.setCellValue((String)map.get("dictLabel"));continue;}if (j==2){Map map = list.get(tier - 3);cell.setCellValue((String)map.get("dictLabel"));continue;}}else {//绘制层级的数据JSONObject bean = new JSONObject(list.get(0));cell.setCellValue(bean.getString(keys.get(j - tier)));}}}//添加总合计行，并合并单元格Row totalRow = sheet.createRow(twoDimensional.size()+1);for (int j = 0; j < keys.size()+tier; j++) {Cell cell = totalRow.createCell(j);if (j<tier){cell.setCellValue("合计");}else {cell.setCellValue(topBean.getString(keys.get(j - tier)));}}if (tier != 1){sheet.addMergedRegion(new CellRangeAddress(twoDimensional.size()+1,twoDimensional.size()+1,0,tier-1));}//合并相同的单元格int lastRowNum = sheet.getLastRowNum();int index = 0;//根据业务只有标签这几列需要合并for (int i = 0; i < tier-1; i++) {//比较相邻cell的值是否相同，并记录for (int j = 0; j < lastRowNum; j++) {Row row = sheet.getRow(j);Cell cell = row.getCell(i);Cell cell2 = row.getCell(i+1);String stringCellValue = cell.getStringCellValue();String stringCellValueNextRow = cell2.getStringCellValue();if ("合计".equals(stringCellValue)){sheet.addMergedRegion(new CellRangeAddress(j,j,i,i+1));continue;}Row nextRow = sheet.getRow(j+1);Cell nextcell = nextRow.getCell(i);String nextStringCellValue = nextcell.getStringCellValue();if (stringCellValue.equals(nextStringCellValue)){if (j+1 == lastRowNum){if (index != 0){sheet.addMergedRegion(new CellRangeAddress(j-index,j+1,i,i));index = 0;}}else {index++;}}else {if (index != 0){sheet.addMergedRegion(new CellRangeAddress(j-index,j,i,i));index = 0;}}//横向合并// row-- 相邻的如果相同合并if (stringCellValueNextRow.equals(stringCellValue) && j != 0 ){sheet.addMergedRegionUnsafe(new CellRangeAddress(j,j,i,i+1));}}}}catch (Exception e){e.printStackTrace();}}

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