客户需求：点击附件后不打开附件，而是直接下载

实现思想：将附件读入InputStream，并写入OutputStream返回给Response

实现代码：

download.jsp:

<a href="<c:url value="/front/download.do?documentId=${document.id}"/>">${document.name}</a>

downloadController.java:

    @RequestMapping("/download.do")public void download(@RequestParam(value = "documentId",required = true)Long documentId,ModelMap modelMap,HttpServletRequest request ,HttpServletResponse response){//保存数据if(documentId > 0){//取得附件信息List<LmsResourceEntity> lmsResourceList = lmsResourceDao.findById(documentId);for(LmsResourceEntity lmsResource : lmsResourceList){//取得附件在服务器上的路径（D:/Tomcat7/webapp/...）String savePath = request.getSession().getServletContext().getRealPath("/") + lmsResource.getUrl();System.out.println("store path is :" + savePath);//Response编码设为UTF-8response.setContentType("text/html;charset=utf-8");try {request.setCharacterEncoding("UTF-8");} catch (UnsupportedEncodingException e) {throw new RuntimeException("设置错误",e);}BufferedInputStream bis = null;BufferedOutputStream bos = null;try {long fileLength = new File(savePath).length();response.setContentType("application/x-msdownload;");//注意！filename需要转码，否则中文名会显示不了response.setHeader("Content-disposition", "attachment; filename=" + new String( lmsResource.getName().getBytes("gb2312"), "ISO8859-1" ) );response.setHeader("Content-Length", String.valueOf(fileLength));//读取文件bis = new BufferedInputStream(new FileInputStream(savePath));//bos设置为Response的OutputStreambos = new BufferedOutputStream(response.getOutputStream());//将文件写入bosbyte[] buff = new byte[2048];int bytesRead;while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {bos.write(buff, 0, bytesRead);}} catch (Exception e) {e.printStackTrace();} finally {if (bis != null)try {bis.close();} catch (IOException e) {throw new RuntimeException("下载失败",e);}if (bos != null)try {bos.close();} catch (IOException e) {throw new RuntimeException("下载失败",e);}}}}else{System.out.println("文件下载无效documentId");}}