如何用vfp以form-data格式上传图片文件到微信服务器

    /**
     * 上传图文消息内的图片获取URL
     * http请求方式: POST，https协议  以表单形式提交
     * https://api.weixin.*/
    @Test
    public void test6(){
        String redisToken = wxService.getRedisToken();
        String urlStr = "https://api.weixin./cgi-bin/media/uploadimg?access_token=ACCESS_TOKEN";
        String replaceUrl = urlStr.replace("ACCESS_TOKEN", redisToken);
        File file = new File("/Users/LiuShihao/IdeaProjects/wxthepublic/FtA17e_zIAqlFyfOZ-tpkbhPmZFQ-EIKGef4NwwPfNaPqGARTs4eX7yrX8gAV5Mv.jpg");
        StringBuilder resp = new StringBuilder();
        String result=null;
        try {
            URL urlObj = new URL(replaceUrl);
            HttpsURLConnection conn = (HttpsURLConnection) urlObj.openConnection();
            conn.setRequestMethod("POST");//以POST方式提交表单
            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.setUseCaches(false);
            conn.setRequestProperty("Connection","Keep-Alive");
            conn.setRequestProperty("Charset","UTF-8");
            //数据边界
            String boundary = "----------"+System.currentTimeMillis();
            conn.setRequestProperty("Content-Type","multipart/form-data; boundary="+boundary);
            //获取输出流
            OutputStream out = conn.getOutputStream();
            //创建文件输入流
            FileInputStream fis = new FileInputStream(file);
            StringBuilder sb = new StringBuilder();
            sb.append("--");
            sb.append(boundary);
            sb.append("\r\n");
            sb.append("Content-Disposition: form-data;name=\"media\"; filename=\""+file.getName()+"\"\r\n");
            sb.append("Content-Type: applicatin/octet-stream\r\n\r\n");
            out.write(sb.toString().getBytes());

            byte[] bytes = new byte[1024];
            int len;
            while((len = fis.read(bytes)) != -1){
                out.write(bytes,0,len);
            }
            String foot = "\r\n--"+boundary+"--\r\n";
            out.write(foot.getBytes());
            out.flush();
            out.close();
            //读取数据
            if(HttpsURLConnection.HTTP_OK==conn.getResponseCode()){

                StringBuffer strbuffer=null;
                BufferedReader reader=null;
                try {
                    strbuffer=new StringBuffer();
                    reader=new BufferedReader(new InputStreamReader(conn.getInputStream()));
                    String lineString=null;
                    while((lineString=reader.readLine())!=null){
                        strbuffer.append(lineString);
                    }
                    result=strbuffer.toString();
                } catch (IOException e) {
                    System.out.println("发送POST请求出现异常！"+e);
                    e.printStackTrace();
                }finally{
                    if(reader!=null){
                        reader.close();
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        System.out.println(result);
        //resp:{"url":"http:\/\/mmbiz.\/mmbiz_jpg\/OsaJQib8ibD8ActRfkHSkvZsntjEjmicVGibcWic0Kbkq8pgnf4BJgytEOUBxmlIM1IBCPsWLOXUW0dUwAZziaiajwNfw\/0"}
        //http://mmbiz./mmbiz_jpg/OsaJQib8ibD8ActRfkHSkvZsntjEjmicVGibcWic0Kbkq8pgnf4BJgytEOUBxmlIM1IBCPsWLOXUW0dUwAZziaiajwNfw/0
    }