java - 技术人员快进来帮帮忙啊，七牛直传报400！

七牛直传，报400，下面是我的方法：

 private static final String LINE_END = "\r\n";

public String postFileWithParameters(String urlStr, Map fileMap,
                                         Map paraMap) throws Exception {
        // creates a unique boundary based on time stamp
        String boundary = "<" + System.currentTimeMillis() + ">";

        URL url = new URL(urlStr);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setRequestMethod("POST");
        connection.setConnectTimeout(TIMEOUT_MILLIS);
        connection.setReadTimeout(TIMEOUT_MILLIS);
        connection.setDoOutput(true);
        connection.setDoInput(true);
        connection.setRequestProperty("Content-Type",
                "multipart/form-data; boundary=" + boundary);
        OutputStream outputStream = connection.getOutputStream();
        PrintWriter writer = new PrintWriter(new OutputStreamWriter(outputStream, CHARSET),
                true);

        if (fileMap != null) {
            Iterator> iter = fileMap.entrySet().iterator();
            while (iter.hasNext()) {
                Map.Entry entry = iter.next();
                String inputName = entry.getKey();
                String inputValue = entry.getValue();
                if (inputValue == null) {
                    continue;
                }
                File file = new File(inputValue);
                String fileName = file.getName();

                writer.append("--" + boundary).append(LINE_END);
                writer.append(
                        "Content-Disposition: form-data; name=\"" + inputName

1. bytesRead = -1;

2. ((bytesRead = inputStream.read(buffer)) != -1) {

                     outputStream.write(buffer, 0, bytesRead);
                 }
                 outputStream.flush();
                 inputStream.close();
   
                 writer.append(LINE_END);
                 writer.flush();
   
             }
         }

1. (paraMap != null) {

              Iterator> iter = paraMap.entrySet().iterator();
              while (iter.hasNext()) {
                  Map.Entry entry = iter.next();
                  String paraKey = entry.getKey();
                  String paraValue = entry.getValue();
                  writer.append("--" + boundary).append(LINE_END);
                  writer.append("Content-Disposition: form-data; name=\"" + paraKey + "\"")
                          .append(LINE_END);
                  writer.append("Content-Type: text/plain; charset=" + CHARSET).append(
                          LINE_END);
                  writer.append(paraValue).append(LINE_END);
                  writer.flush();
              }
          }
   
          writer.append("--" + boundary + "--").append(LINE_END).flush();
          writer.close();
   
          LogX.d(urlStr, connection.getResponseCode() + "");

2. (connection.getResponseCode()) {

              case HttpURLConnection.HTTP_OK:
              case HttpURLConnection.HTTP_CREATED:
                  StringBuilder sb = new StringBuilder();
                  BufferedReader br = new BufferedReader(
                          new InputStreamReader(connection.getInputStream(), "utf-8"));
                  String line = null;
                  while ((line = br.readLine()) != null) {
                      sb.append(line + "\n");
                  }
   
                  br.close();
                  LogX.d("返回", sb.toString());
                  connection.disconnect();
                  return sb.toString();
   
              case HttpURLConnection.HTTP_UNAUTHORIZED:
                  connection.disconnect();
                  throw new IllegalArgumentException(connection.getResponseMessage());
   
              case HttpURLConnection.HTTP_NOT_FOUND:
                  connection.disconnect();
                  throw new Exception(connection.getResponseMessage());
   
              case HttpURLConnection.HTTP_BAD_REQUEST:
                  connection.disconnect();
                  throw new IllegalArgumentException(connection.getResponseMessage());
   
              case HttpURLConnection.HTTP_FORBIDDEN:
                  connection.disconnect();
                  JsonObject jo = new JsonObject();
                  jo.addProperty(JSON_KEY_ERROR, ERROR_FORBIDDEN);
                  return jo.toString();
              default:
                  connection.disconnect();
                  throw new Exception(connection.getResponseMessage());
          }
      }
      

   下面是我的传值：

   urlStr = "http://upload.qiniu.com";
   
   HashMap fileMap = new HashMap<>();
   fileMap.put("file", mPhotoPath);
   
   HashMap paraMap = new HashMap<>();
   paraMap.put("token", token);
   paraMap.put("key",key);