poi导出百万数据到excel

poi框架在excel导入导出在java项目中经常会用到，但是之前用 HSSF和XSSF是POI导出都会有数据的瓶颈，大概在导出数据达到3万条以上时间上就很慢，再多的数据基本就无法导出。因此POI 3.8版本开始，提供了一种基于XSSF的低内存占用的API—-SXSSF 。测试导出100万数据组装以及生成excel大概要10分钟左右。效率还是非常高的。话不多少直接上代码。。。。

 /**     * 导出Excel     *      * @param sheetName sheet名称     * @param titleArrary 标题     * @param dataList 数据列表     * @param filePath 文件路径     *  @param fileName 文件名     * @throws Exception     *     */    public static void exportSXSSFExcel(String sheetName, String[] titleArrary, List<String[]> dataList, String filePath,HttpServletResponse response,String fileName) throws Exception {        // 内存中缓存记录数 建议10000 不然会导致内存溢出        SXSSFWorkbook workbook = new SXSSFWorkbook(10000);        Sheet sheet = workbook.createSheet(sheetName);        Font titleFont = workbook.createFont();        titleFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);        CellStyle titleCellStyle = workbook.createCellStyle();        titleCellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);        titleCellStyle.setFont(titleFont);        int rowIndex = 0;        Row row = sheet.createRow(rowIndex++);        // 标题        int cellSize = titleArrary.length;        for (int i = 0; i < cellSize; i++) {            Cell cell = row.createCell(i);            cell.setCellStyle(titleCellStyle);            cell.setCellValue(titleArrary[i]);            if (titleArrary[i] != null) {                sheet.setColumnWidth(i, titleArrary[i].getBytes().length * 2 * 140);            }        }        // 数据        CellStyle dataCellStyle = workbook.createCellStyle();        dataCellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);        for (String[] data : dataList) {            row = sheet.createRow(rowIndex);            // 遍历列            for (int i = 0; i < data.length; i++) {                Cell cell = row.createCell(i);                cell.setCellStyle(dataCellStyle);                cell.setCellValue(data[i]);            }            rowIndex++;        }        if (!fileName.endsWith(".xlsx")) {            fileName += ".xlsx";        }        if(StringUtil.isNotEmpty(filePath)){        File saveFile = new File(filePath);        if (!saveFile.exists()) {            saveFile.getParentFile().mkdirs();            saveFile.createNewFile();        }        OutputStream outputStream = new FileOutputStream(saveFile);        workbook.write(outputStream);        outputStream.close();        }        if(response!=null){            response.setContentType("application/vnd.ms-excel;charset=utf-8");            fileName = response.encodeURL(new String(fileName.getBytes("utf-8"), "iso8859-1"));            response.addHeader("Content-Disposition", "attachment;filename=" + fileName);            OutputStream outputStream =response.getOutputStream();            workbook.write(outputStream);            outputStream.close();        }    }