图片下载JAVA

// 页面form
        OptActListNewForm actListForm = (OptActListNewForm)form;
        // 转换为Flex转换数据类型
        List<OptActListNew> optList = optActMonitorService.getDownLoadData(actListForm, user);
        OptActListNew optAct = (OptActListNew)optList.get(0);
        List listData = this.buildExcelData(optList);
        response.setHeader("Content-Type", "application/force-download");
        response.setHeader("Content-Type", "application/vnd.ms-excel");
        String fileName = new String("xxx_xx".getBytes("GBK"),
                "ISO-8859-1");
        response.setHeader("Content-Disposition", "attachment;filename="
                + fileName + ".xls");
        ServletOutputStream out = response.getOutputStream();
        //创建excel工作薄
        WritableWorkbook wwb = Workbook.createWorkbook(out);
        //创建excel工作表
        WritableSheet ws = wwb.createSheet("xxxx", 0);
        //给出标题
        WritableFont titleWF = new WritableFont(WritableFont.ARIAL, 20,
                WritableFont.BOLD, false, UnderlineStyle.NO_UNDERLINE,
                Colour.BLACK);
        WritableCellFormat titleWCF = new WritableCellFormat(titleWF);
        Label tileLab = new Label(5, 0, "xxxx", titleWCF);//加入标题
        ws.addCell(tileLab);
        //添加图片对象
        ByteArrayOutputStream bos = null;
        BufferedImage chart = null;
        try
        {
            bos = new ByteArrayOutputStream();
            chart = ImageIO.read(request.getInputStream());
            ImageIO.write(chart, "jpeg", bos);
            WritableImage img = new WritableImage(0, ws.getRows() + 1, 15, 26,
                    bos.toByteArray());
            ws.addImage(img);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        finally
        {
            bos.close();
        }
        wwb.write();
        wwb.close();