public class FileAction extends DispatchAction {

    private JDBConnection connection =new JDBConnection();
//以下方法实现文件的上传    public ActionForward upLoadFile(ActionMapping mapping, ActionForm form,
                                    HttpServletRequest request,
                                    HttpServletResponse response) throws
            Exception {
        Date date = new Date();
        FileActionForm fileActionForm = (FileActionForm) form;
        FormFile file = fileActionForm.getFile(); //获取当前的文件        String dir = servlet.getServletContext().getRealPath("/image");
        String path = upload(dir, file); //实现文件的上传的功能,并且返回上传服务器的路径        path="image/"+path;
        String fileName = Chinese.toChinese(fileActionForm.getFileName()); //获取文件的名称        String fileSize = String.valueOf(file.getFileSize());
        String fileDate = DateFormat.getDateInstance().format(date);
        String sql = "insert into tb_file values('" + fileName + "','" +
                     fileSize + "','" + fileDate + "','" + path + "')";
        connection.executeUpdate(sql);
        connection.closeConnection();
        return mapping.findForward("upLoadFileResult");
    }

    public String upload(String dir, FormFile formFile) throws Exception {
         Date date = new Date();
        //取欲上传的文件的名字和长度        String fname = formFile.getFileName();
        //将上传时间加入文件名        int i = fname.indexOf(".");
        String name = String.valueOf(date.getTime());
        String type = fname.substring(i + 1);
        fname = name + "." + type;
        InputStream streamIn = formFile.getInputStream();    //创建读取用户上传文件的对象        File uploadFile = new File(dir);   //创建把上传数据写到目标文件的对象        if (!uploadFile.exists() || uploadFile == null) {  //判断指定路径是否存在，不存在则创建路径            uploadFile.mkdirs();
        }
        String path = uploadFile.getPath() + "/" + fname;
        OutputStream streamOut = new FileOutputStream(path);
        int bytesRead = 0;
        byte[] buffer = new byte[8192];
        while ((bytesRead = streamIn.read(buffer, 0, 8192)) != -1) {
            streamOut.write(buffer, 0, bytesRead);
        }
        streamOut.close();
        streamIn.close();
        formFile.destroy();
        return fname;
    }


    //实现文件的下载    public ActionForward downFile(ActionMapping mapping, ActionForm form,
                                  HttpServletRequest request,
                                  HttpServletResponse response) throws
            Exception {
        String path = request.getParameter("path");
        BufferedInputStream bis = null;
        BufferedOutputStream bos = null;
        OutputStream fos = null;
        InputStream fis = null;
        String filepath = servlet.getServletContext().getRealPath("/" + path);
        File uploadFile = new File(filepath);
        fis = new FileInputStream(uploadFile);
        bis = new BufferedInputStream(fis);
        fos = response.getOutputStream();
        bos = new BufferedOutputStream(fos);
        response.setHeader("Content-disposition",
                           "attachment;filename=" +
                           URLEncoder.encode(path, "utf-8"));
        int bytesRead = 0;
        byte[] buffer = new byte[8192];
        while ((bytesRead = bis.read(buffer, 0, 8192)) != -1) {
            bos.write(buffer, 0, bytesRead);
        }
        bos.flush();
        fis.close();
        bis.close();
        fos.close();
        bos.close();

        return null;
    }

}