HttpURLConnection上传文件(图片)

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需求:用HttpURLConnection模拟上传图片并把图片的名称也要传递过去.

简单分析:写入流的时候依次写入 图片名称 + "|" 分隔符 +  图片流

然后服务器接收的再处理流.分别取出图片名和图片.


/** *//**
     * 上传方法
     * 返回上传完毕的文件名
     * *
     */
    public String upload(File f)
    {
        try
        {
            //服务器IP(这里是从属性文件中读取出来的)
            String hostip = FileSupport.getServerIP();
            URL url = new URL("http://"+ hostip +"/oxServer/ReceiveServlet");
           
            HttpURLConnection uc = (HttpURLConnection) url.openConnection();
            //上传图片的一些参数设置
            uc
                    .setRequestProperty(
                            "Accept",
                            "image/gif,   image/x-xbitmap,   image/jpeg,   image/pjpeg,   application/vnd.ms-excel,   application/vnd.ms-powerpoint,   application/msword,   application/x-shockwave-flash,   application/x-quickviewplus,   */*");
            uc.setRequestProperty("Accept-Language", "zh-cn");
            uc
                    .setRequestProperty("Content-type",
                            "multipart/form-data;   boundary=---------------------------7d318fd100112");
            uc.setRequestProperty("Accept-Encoding", "gzip,   deflate");
            uc
                    .setRequestProperty("User-Agent",
                            "Mozilla/4.0   (compatible;   MSIE   6.0;   Windows   NT   5.1)");
            uc.setRequestProperty("Connection", "Keep-Alive");
            uc.setDoOutput(true);
            uc.setUseCaches(true);
       
            //读取文件流
            int size = (int) f.length();
            byte[] data = new byte[size];
            FileInputStream fis = new FileInputStream(f);
            OutputStream out = uc.getOutputStream();
            fis.read(data, 0, size);
            //写入文件名
            out.write(f.getName().trim().getBytes());
            //写入分隔符
            out.write('|');
            //写入图片流
            out.write(data);
            out.flush();
            out.close();
            fis.close();
           
            //读取响应数据
            int code = uc.getResponseCode();
            String sCurrentLine = "";
            //存放响应结果
            String sTotalString = "";
            if (code == 200)
            {
                java.io.InputStream is = uc.getInputStream();
                BufferedReader reader = new BufferedReader(
                        new InputStreamReader(is));
                while ((sCurrentLine = reader.readLine()) != null)
                    if (sCurrentLine.length() > 0)
                        sTotalString = sTotalString + sCurrentLine.trim();
            }
            else
            {
                sTotalString = "远程服务器连接失败,错误代码:" + code;
            }
            return sTotalString;
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        return null;
    }

服务器Servlet:

public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException
    {
        ServletInputStream inStream = request.getInputStream(); // 取HTTP请求流
        int size = request.getContentLength(); // 取HTTP请求流长度

        byte[] buffer = new byte[size]; // 用于缓存每次读取的数据
        byte[] result = new byte[size]; // 用于存放结果的数组
        int count = 0;
        int rbyte = 0;
        // 循环读取
        while (count < size)
        {
            rbyte = inStream.read(buffer); // 每次实际读取长度存于rbyte中 sflj
            for (int i = 0; i < rbyte; i++)
            {
                result[count + i] = buffer[i];
            }
            count += rbyte;
        }

        // 先找到文件名和图片流的标志位'|'
        int index = 0;
        for (int i = 0; i < result.length; i++)
        {
            byte b = result[i];
            if (b == '|')
            {
                index = i;
                break;
            }
        }

        // 存放文件名
        byte name[] = new byte[index + 1];
        // 存放图片字节
        byte[] img = new byte[size - index];
        for (int i = 0; i < result.length; i++)
        {
            if (i < index)
            {
                name[i] = result[i];
            }
            if (i > index)
            {
                // 这时注意img数组的index要从0开始
                img[i - index - 1] = result[i];
            }
        }
        // 还原文件名
        String fileName = new String(name);

        inStream.close();

        String newFileName = renameFile(fileName);
        // 响应客户端
        response.setContentType("text/html");
        // 注意响应中文数据时要设置
        response.setCharacterEncoding("GBK");
        PrintWriter out = response.getWriter();
        //可能情况 0 数据库无相关记录 1 文件名不符合要求 其它情况为正常
        if(newFileName.equals("0"))
        {
            out.write("0|" + fileName);
        }
        else if(newFileName.equals("1"))
        {
            out.write("1|" + fileName);
        }
        else
        {
            out.write(fileName);
        }
        out.close();
        //上传错误中止后续操作
        if(newFileName.length()<= 1)
        {
            return;
        }
       
        File f = new File(ImageSupport.getOriginal() + "/" + newFileName);
        FileOutputStream fos = new FileOutputStream(f);
        fos.write(img);
        fos.flush();
        fos.close();
        // 改变图片大小后重新放置到新地点
        ImageSupport.changeImageSize(f, ImageSupport.getAfter() + "/"
                + newFileName, 300, 300);
    }

我写的是一个批量上传图片的程序,经测试通过.

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