Http协议之content

private static JSONObject connUpload(String baseUrl, Map<String, String> params, String content) throws IOException, JSONException {
        
        String end = "\r\n";
        String hyphens = "--";
        String boundary = UUID.randomUUID().toString().replace("-", "");
        
        //将需求连接转换成实际链接  如加上手机的基本信息等。
        String realUrl = HttpUtil.buildUrl(baseUrl);
        LogUtil.i("realurl:" + realUrl);
        
        URL url = new URL(realUrl);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setConnectTimeout(TIMEOUT);
        
        //Post 请求不能使用缓存
        conn.setUseCaches(false);
        conn.setDoOutput(true);
        StringBuilder sb = new StringBuilder();
//        sb.append("&userDto.chatMessage.receiver=" + msg.getReceiver());
//        sb.append("&userDto.chatMessage.type=" + msg.getType());
        
        conn.setRequestProperty("Connection", "Keep-Alive");
        conn.setRequestProperty("Charset", "UTF-8");
        conn.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
        conn.setRequestProperty("enctype", "multipart/form-data;");
        
        DataOutputStream writer = new DataOutputStream(conn.getOutputStream());
        
        writer.writeBytes("Content-Type: multipart/form-data;boundary=" + boundary + end);
        writer.writeBytes(hyphens + boundary + end);
        
        if(params != null && params.size() > 0) {
            for(String key : params.keySet()) {
                sb.append("Content-Disposition: form-data; name=\"").append(key).append("\"").append(end).append(end).append(params.get(key)).append(end + hyphens).append(boundary).append(end);  
            }
        }
        
        writer.writeBytes(sb.toString());
        
        // 构造DataOutputStream流 
        writer.writeBytes("Content-Disposition: form-data; " + "name=\"file\";filename=\"" + content + "\"" + end);
        writer.writeBytes("Content-Type: multipart/form-data;" + end);
        writer.writeBytes(end);
        
        /* 取得文件的FileInputStream */
        FileInputStream fStream = new FileInputStream(content);
        /* 设定每次写入1024bytes */
        byte[] buffer = new byte[Constant.NET_BUFF_SIZE];
        int length = -1;
        /* 从文件读取数据到缓冲区 */
        while ((length = fStream.read(buffer)) != -1) {
            /* 将数据写入DataOutputStream中 */
            LogUtil.i("stream: "+length);
            writer.write(buffer, 0, length);
        }
        writer.writeBytes(end);
        fStream.close();
        
        writer.writeBytes(hyphens + boundary + hyphens + end);
        writer.flush();
        writer.close();
        
        //, Constant.CHARSET
        BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
        
        sb = new StringBuilder();
        char[] buff = new char[Constant.NET_BUFF_SIZE];
        int flag = 0;
        while((flag = reader.read(buff)) != -1) {
            sb.append(buff, 0, flag);
        }
        
        reader.close();
        conn.disconnect();
        
        LogUtil.i("response:" + sb);
        
        return new JSONObject(sb.toString());
    }