记录使用Java Poi导出Excel表格，合并单元格，单元格背景颜色，单元格边框

预览的导出效果

实现代码

        Workbook wb = new XSSFWorkbook();
        String sheetName = "全过程咨询";
        List<ExcelTitle> excelTitles = new ArrayList<>();
        excelTitles.add(new ExcelTitle("序号" , null));
        excelTitles.add(new ExcelTitle("业务部/分公司" , null));
        excelTitles.add(new ExcelTitle("工程实施项目部" , null));
        List<String> columns = new ArrayList<String>(){{
            add("公司整体形象");
            add("合同履行情况及信誉度");
        }};
        excelTitles.add(new ExcelTitle("工程监理过程控制能力/招标项目服务水平能力/项目咨询造价控制能力" , columns));
        excelTitles.add(new ExcelTitle("阿达瓦达瓦萨达" , null));
        columns = new ArrayList<String>(){{
            add("项目服务质量、进度控制/咨询服务质量、进度控制");
            add("项目服务的造价控制/咨询业务能力");
            add("项目服务的安全控制/咨询服务的时间安排");
        }};
        excelTitles.add(new ExcelTitle("公司整体实力" , columns));
        excelTitles.add(new ExcelTitle("发干哈阿斯达斯的" , null));
        columns = new ArrayList<String>(){{
            add("项目服务质量、进度控制/咨询服务质量、进度控制");
            add("项目服务的造价控制/咨询业务能力");
            add("项目服务的安全控制/咨询服务的时间安排");
            add("项目服务的造价控制/咨询业务能力");
            add("项目服务的安全控制/咨询服务的时间安排");
        }};
        excelTitles.add(new ExcelTitle("4566666666546456564564" , columns));

        // 计算实际列数
        int countColNums = 0;
        for (ExcelTitle excelTitle : excelTitles) {
            if(excelTitle.getColumns() != null){
                // 如果有子项，那么不统计父项的数量 不然会多出列数
                countColNums += excelTitle.getColumns().size();
            }else{
                countColNums++;
            }
        }

        Sheet sheet = wb.createSheet(sheetName);

        int rowSize = 1;
        Row row = sheet.createRow(rowSize);
        row.setHeight((short) (50*20));

        // 第四步，创建单元格，并设置值表头 设置表头居中
        CellStyle style = wb.createCellStyle();
        //设置样式对齐方式：水平\垂直居中
        style.setAlignment(HorizontalAlignment.CENTER);
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        style.setFillForegroundColor(IndexedColors.GOLD.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        // 单元格边框
        style.setBorderBottom(BorderStyle.THIN);
        style.setBorderLeft(BorderStyle.THIN);
        style.setBorderRight(BorderStyle.THIN);
        style.setBorderTop(BorderStyle.THIN);
        // 文本自动换行
        style.setWrapText(true);

        int columnWidth = 150*20;

        // 记录父项开始的列数
        Map<String, Integer> titleStartColNumMap = new HashMap<>();

        // 创建标题
        int n = 0;
        for (int i = 0; i < countColNums; i++) {
            ExcelTitle excelTitle = excelTitles.get(n);
            // 合并开始列
            int startRangeSize = i;
            // 合并结束列
            int endRangeColSize = i;

            if(excelTitle.getColumns() != null){
                titleStartColNumMap.put(excelTitle.getName() , i);
                for (int k = 0; k < excelTitle.getColumns().size(); k++) {
                    Cell cell = row.createCell(i + k);
                    cell.setCellStyle(style);
                    cell.setCellValue(excelTitle.getName());
                    sheet.setColumnWidth((short) i + k , columnWidth);
                }

                i += excelTitle.getColumns().size() - 1;
                endRangeColSize = i;
            }else{
                Cell cell = row.createCell(i);
                cell.setCellStyle(style);
                cell.setCellValue(excelTitle.getName());
                sheet.setColumnWidth((short) i , columnWidth);
            }

            int rangeRowSize = excelTitle.getColumns() == null ? row.getRowNum() + 1 : row.getRowNum();
            // 合并单元格
            CellRangeAddress rangeAddress = new CellRangeAddress(row.getRowNum(), rangeRowSize, startRangeSize, endRangeColSize);
            sheet.addMergedRegion(rangeAddress);

            // 增加合并后的单元格边框
            RegionUtil.setBorderBottom(BorderStyle.THIN, rangeAddress, sheet); // 下边框
            RegionUtil.setBorderLeft(BorderStyle.THIN, rangeAddress, sheet); // 左边框
            RegionUtil.setBorderRight(BorderStyle.THIN, rangeAddress, sheet); // 有边框
            RegionUtil.setBorderTop(BorderStyle.THIN, rangeAddress, sheet); // 上边框

            n++;
        }

        row = sheet.getRow(++rowSize);
        row.setHeight((short) (50*20));
         // 将子项内容添加至父项下面的单元格
        for (int i = 0; i < excelTitles.size(); i++) {
            ExcelTitle excelTitle = excelTitles.get(i);
            if(excelTitle.getColumns() != null){
                for (int j = 0; j < excelTitle.getColumns().size(); j++) {
                    Cell cell = row.createCell(titleStartColNumMap.get(excelTitle.getName()) + j);
                    cell.setCellStyle(style);
                    cell.setCellValue(excelTitle.getColumns().get(j));
                    sheet.setColumnWidth((short) i , columnWidth);
                }
            }
        }

        row = sheet.createRow(0);
        row.setHeight((short) (30*20));

        style = wb.createCellStyle();
        //设置样式对齐方式：水平\垂直居中
        style.setAlignment(HorizontalAlignment.CENTER);
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        // 标题
        Cell cell = row.createCell(0);
        cell.setCellValue("2020年上半年（   ）分公司（部门）监理、咨询客户满意度调查情况明细");
        cell.setCellStyle(style);
        CellRangeAddress rangeAddress = new CellRangeAddress(0, 0, 0, countColNums - 1);
        sheet.addMergedRegion(rangeAddress);
        file.getParentFile().mkdirs();
        FileOutputStream os = new FileOutputStream(file);
        wb.write(os);
        os.flush();
        os.close();

        public static class ExcelTitle {
            private String name;

            private List<String> columns;

            public ExcelTitle() {
            }

            public ExcelTitle(String name, List<String> columns) {
                this.name = name;
                this.columns = columns;
            }

            public String getName() {
                return name;
            }

            public void setName(String name) {
                this.name = name;
            }

            public List<String> getColumns() {
                return columns;
            }

            public void setColumns(List<String> columns) {
                this.columns = columns;
            }
    }

      pom.xml 版本
      <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>4.1.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>4.1.0</version>
        </dependency>