SpringMVC生成Excel下载

SpringMVC controller里的方法:

@RequestMapping(value="/notify/download",produces = {"application/vnd.ms-excel;charset=UTF-8"})
    public String download(HttpSession session,HttpServletResponse response){
        try {
            User user= (User) session.getAttribute("user");
            String queryParam="";
            if (!user.getRole().getName().equals("超级管理员")){
                queryParam+=" and sbn.be_notified_user_id = "+user.getId();
            }
            List<Notify> notifyList=slDao.getNotifyList(queryParam,0,999999999);
            String fileName="纠错统计表";
            List<Map<String,Object>> list=createExcelRecord(notifyList);
            String columnNames[]={"发起纠错时间","纠错人","负责人","标准库名","纠错内容","纠错状态"};//列名
            String keys[]    =     {"time","notifyUser","beNotifiedUser","standardName","content","finish"};//map中的key
            ByteArrayOutputStream os = new ByteArrayOutputStream();
            try {
                ExcelUtil.createWorkBook(list,keys,columnNames).write(os);
            } catch (IOException e) {
                e.printStackTrace();
            }
            byte[] content = os.toByteArray();
            InputStream is = new ByteArrayInputStream(content);
            // 设置response参数，可以打开下载页面
            response.reset();
            response.setContentType("application/vnd.ms-excel;charset=utf-8");
            response.setHeader("Content-Disposition", "attachment;filename="+ new String((fileName + ".xls").getBytes(), "iso-8859-1"));
            ServletOutputStream out = response.getOutputStream();
            BufferedInputStream bis = null;
            BufferedOutputStream bos = null;
            try {
                bis = new BufferedInputStream(is);
                bos = new BufferedOutputStream(out);
                byte[] buff = new byte[2048];
                int bytesRead;
                // Simple read/write loop.
                while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
                    bos.write(buff, 0, bytesRead);
                }
            } catch (final IOException e) {
                throw e;
            } finally {
                if (bis != null)
                    bis.close();
                if (bos != null)
                    bos.close();
            }
        }catch (Exception e){

        }

        return null;
    }

所调用的createExcelRecord方法

private List<Map<String, Object>> createExcelRecord(List<Notify> notifyList) {
        List<Map<String, Object>> listmap = new ArrayList<Map<String, Object>>();
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("sheetName", "sheet1");
        listmap.add(map);
        for (int j = 0; j < notifyList.size(); j++) {
            Notify notify=notifyList.get(j);
            Map<String, Object> mapValue = new HashMap<String, Object>();
            mapValue.put("time", notify.getTime());
            mapValue.put("notifyUser",notify.getNotifyUserNickname());
            mapValue.put("beNotifiedUser",notify.getBeNotifiedUserNickname());
            mapValue.put("standardName",notify.getStandardName());
            mapValue.put("content",notify.getContent());
            String finish=notify.getFinishFlag()+"";
            if (finish.equals("0")) finish="已纠错";
            else finish="未纠错";
            mapValue.put("finish",finish);
            listmap.add(mapValue);
        }
        return listmap;
    }

所调用的ExcelUtil

public class ExcelUtil {
    /**
     * 创建excel文档，
     *  list 数据
     * @param keys list中map的key数组集合
     * @param columnNames excel的列名
     * */
    public static Workbook createWorkBook(List<Map<String, Object>> list, String []keys, String columnNames[]) {
        // 创建excel工作簿
        Workbook wb = new HSSFWorkbook();
        // 创建第一个sheet（页），并命名
        Sheet sheet = wb.createSheet(list.get(0).get("sheetName").toString());
        // 手动设置列宽。第一个参数表示要为第几列设；，第二个参数表示列的宽度，n为列高的像素数。
        for(int i=0;i<keys.length;i++){
            sheet.setColumnWidth((short) i, (short) (35.7 * 200));
        }

        // 创建第一行
        Row row = sheet.createRow((short) 0);

        // 创建两种单元格格式
        CellStyle cs = wb.createCellStyle();
        CellStyle cs2 = wb.createCellStyle();

        // 创建两种字体
        Font f = wb.createFont();
        Font f2 = wb.createFont();

        // 创建第一种字体样式（用于列名）
        f.setFontHeightInPoints((short) 10);
        f.setColor(IndexedColors.BLACK.getIndex());
        f.setBoldweight(Font.BOLDWEIGHT_BOLD);

        // 创建第二种字体样式（用于值）
        f2.setFontHeightInPoints((short) 10);
        f2.setColor(IndexedColors.BLACK.getIndex());

//        Font f3=wb.createFont();
//        f3.setFontHeightInPoints((short) 10);
//        f3.setColor(IndexedColors.RED.getIndex());

        // 设置第一种单元格的样式（用于列名）
        cs.setFont(f);
        cs.setBorderLeft(CellStyle.BORDER_THIN);
        cs.setBorderRight(CellStyle.BORDER_THIN);
        cs.setBorderTop(CellStyle.BORDER_THIN);
        cs.setBorderBottom(CellStyle.BORDER_THIN);
        cs.setAlignment(CellStyle.ALIGN_CENTER);

        // 设置第二种单元格的样式（用于值）
        cs2.setFont(f2);
        cs2.setBorderLeft(CellStyle.BORDER_THIN);
        cs2.setBorderRight(CellStyle.BORDER_THIN);
        cs2.setBorderTop(CellStyle.BORDER_THIN);
        cs2.setBorderBottom(CellStyle.BORDER_THIN);
        cs2.setAlignment(CellStyle.ALIGN_CENTER);
        //设置列名
        for(int i=0;i<columnNames.length;i++){
            Cell cell = row.createCell(i);
            cell.setCellValue(columnNames[i]);
            cell.setCellStyle(cs);
        }
        //设置每行每列的值
        for (short i = 1; i < list.size(); i++) {
            // Row 行,Cell 方格 , Row 和 Cell 都是从0开始计数的
            // 创建一行，在页sheet上
            Row row1 = sheet.createRow((short) i);
            // 在row行上创建一个方格
            for(short j=0;j<keys.length;j++){
                Cell cell = row1.createCell(j);
                cell.setCellValue(list.get(i).get(keys[j]) == null?" ": list.get(i).get(keys[j]).toString());
                cell.setCellStyle(cs2);
            }
        }
        return wb;
    }
}

所需要引用的maven包:

<!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>3.15</version>
        </dependency>