设置输出文件的列宽，防止文件过于丑陋

Sheet sheet = workbook.createSheet(FileConstants.ERROR_FILE_SHEET_NAME);
sheet.setColumnWidth(0, 40 * 256);
sheet.setColumnWidth(1, 20 * 256);
sheet.setColumnWidth(2, 20 * 256);
sheet.setColumnWidth(3, 20 * 256);

实现标题行的第一个字符为红色，效果如图

//这边的0,1   就是设置第一个字符  

Font font = workbook.createFont(); font.setColor(IndexedColors.RED.getIndex());

RichTextString store = workbook.getCreationHelper().createRichTextString(FileConstants.UPDATE_TEMPLATE_NAMES.get(Constants.ZERO)); store.applyFont(0, 1, font);

titleRow.createCell(Constants.ONE_INT).setCellValue(store);

判断如果是第一列的话   设置字体为红色

if (Constants.ZERO.equals(columnIndex)) {

    cellStyle.setFont(font);
    cell.setCellStyle(cellStyle);
}

将文件上传oss保存，可以忽略

try (InputStream inputStream = new ByteArrayInputStream(out.toByteArray())) {
    aliyunOssUtil.uploadFile(ossFilePath, inputStream);
}

 完整代码如下：

    private void uploadErrorFile(List<BatchUpdateStatusFileDTO> list, String fileBatchId) {

        try (ByteArrayOutputStream out = new ByteArrayOutputStream();
             Workbook workbook = new XSSFWorkbook()) {
            Sheet sheet = workbook.createSheet(FileConstants.ERROR_FILE_SHEET_NAME);
            sheet.setColumnWidth(0, 40 * 256);
            sheet.setColumnWidth(1, 20 * 256);
            sheet.setColumnWidth(2, 20 * 256);
            sheet.setColumnWidth(3, 20 * 256);
            // 创建标题行
            Row titleRow = sheet.createRow(0);
            titleRow.createCell(Constants.ZERO).setCellValue(StringPool.EMPTY);
            Font font = workbook.createFont();
            font.setColor(IndexedColors.RED.getIndex());
            RichTextString store = workbook.getCreationHelper().createRichTextString(FileConstants.UPDATE_TEMPLATE_NAMES.get(Constants.ZERO));
            store.applyFont(0, 1, font);
            titleRow.createCell(Constants.ONE_INT).setCellValue(store);
            RichTextString number = workbook.getCreationHelper().createRichTextString(FileConstants.UPDATE_TEMPLATE_NAMES.get(Constants.ONE_INT));
            number.applyFont(0, 1, font);
            titleRow.createCell(Constants.TWO_INT).setCellValue(number);
            RichTextString status = workbook.getCreationHelper().createRichTextString(FileConstants.UPDATE_TEMPLATE_NAMES.get(Constants.TWO_INT));
            status.applyFont(0, 1, font);
            titleRow.createCell(Constants.THREE_INT).setCellValue(status);
            // 创建数据行
            for (int i = 0; i < theResList.size(); i++) {
                BatchUpdateStatusFileDTO data = theResList.get(i);
                Row row = sheet.createRow(i + 1);
                createCell(row, Constants.ZERO, data.getCheckResult(), workbook, font);
                createCell(row, Constants.ONE_INT, data.getSalesStore(), workbook, font);
                createCell(row, Constants.TWO_INT, data.getSalesOrder(), workbook, font);
                createCell(row, Constants.THREE_INT, data.getSalesStatus(), workbook, font);
            }
            String ossFilePath = String.format(FileConstants.BATCH_UPDATE_ERROR_FILE_PATH, fileBatchId);
            // 将Excel输出为InputStream
            workbook.write(out);
            try (InputStream inputStream = new ByteArrayInputStream(out.toByteArray())) {
                aliyunOssUtil.uploadFile(ossFilePath, inputStream);
            }
        } catch (Exception e) {
            log.error("---Modify the order status in batches, failed to upload an error file---", e);
        }
    }


    private void createCell(Row row, int columnIndex, Object value, Workbook workbook, Font font) {
        Cell cell = row.createCell(columnIndex);
        if (value instanceof String) {
            cell.setCellValue((String) value);
        } else if (value instanceof Integer) {
            cell.setCellValue((Integer) value);
        } else {
            cell.setCellValue(value.toString());
        }
        CellStyle cellStyle = workbook.createCellStyle();
        cellStyle.setWrapText(Boolean.TRUE);
        cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);
        cell.setCellStyle(cellStyle);
        if (Constants.ZERO.equals(columnIndex)) {

            cellStyle.setFont(font);
            cell.setCellStyle(cellStyle);
        }
    }