上传时限制文件类型和文件大小。。。。。。。。

Question

我用servlet来做上传，代码如下：
   public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {        response.setContentType("text/html;charset=gb2312");
        HttpSession session = request.getSession();
        PrintWriter out = response.getWriter();
        String tempfilename = (String) session.getId(); // 会话ID
        String path = request.getRealPath("/") + "Accessory/"; // 取物理路经
        File f1 = new File(path, tempfilename);  //File对象
        
        int n;
        try {
            InputStream in = request.getInputStream(); // 取得请求输入流            
            BufferedInputStream my_in = new BufferedInputStream(in);
            FileOutputStream fout = new FileOutputStream(f1);
            BufferedOutputStream my_out = new BufferedOutputStream(fout);
            byte[] b = new byte[10000];
            while ((n = my_in.read(b)) != -1) {
                my_out.write(b, 0, n);
            }
            my_out.flush();
            my_out.close();
            fout.close();
            my_in.close();
            in.close();
            //读取临时文件f1,从中获取上传文件的名字和上传文件的内容。
            RandomAccessFile random1 = new RandomAccessFile(f1, "r");
            random1.readLine();
            String filename = random1.readLine();
            byte[] b2 = filename.getBytes("ISO-8859-1");
            filename = new String(b2);
            int pointer = filename.lastIndexOf('\\');
            filename = filename.substring(pointer + 1, filename.length() - 1);
            File f2 = new File(path, filename);
            RandomAccessFile random2 = new RandomAccessFile(f2, "rw");
            random1.seek(0);
            for (int i = 1; i <= 4; i++) {
                String tempstr = random1.readLine();
            }
            long startPoint = random1.getFilePointer();
            random1.seek(random1.length());
            long  = random1.getFilePointer();
            int j = 0;
            long endPoint = 0;
            while (( >= 0) && (j <= 5)) {
                --;
                random1.seek();
                n = random1.readByte();
                if (n == '\n') {
                    j++;
                    endPoint = random1.getFilePointer();
                }
            }
            long length = endPoint - startPoint + 1;
            int order = (int) (length / 10000);
            int left = (int) (length % 10000);
            byte[] c = new byte[10000];
            random1.seek(startPoint);
            for (int i = 0; i < order; i++) {
                random1.read(c);
                random2.write(c);
            }
            random1.read(c, 0, left);
            random2.write(c, 0, left);
            random1.close();
            random2.close();
            f1.delete();
            
            out.print("<script language='javascript'>");
            out.print("alert('文件上传成功!');");
            out.print("window.location='FileUpLoad.jsp';");
            out.print("</script>");
            
        } catch (IOException e) {
            
            e.printStackTrace();
            out.print("<script language='javascript'>");
            out.print("alert('文件上传失败!');");
            out.print("window.location='FileUpLoad.jsp';");
            out.print("</script>");
        }
    }    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        this.doGet(request, response);
    }
要怎么限制文件的类型和大小啊？？

Answer 1

File f1 = new File(path, tempfilename);  //File对象f1.length()不是可以得到文件的大小吗？
与你规定的大小对比啊，大于规定的，就抛出异常吧。

Answer 2

filename = new String(b2);
            int pointer = filename.lastIndexOf('\\');
            filename = filename.substring(pointer + 1, filename.length() - 1);filename你不也得到了吗，判断一下后缀不就可以限制你要上传的类型了。