HttpURLConnection PUT到Google云端存储,提供错误403

我尝试使用XML API将文件上传到Google云端存储.我为每次上传生成了正确的GoogleAccessId,到期日期和签名.奇怪的是我可以使用Postman(Chrome应用程序)PUT文件,所以我确定网址没问题.我只是不能使用我的Android Java程序(它返回给我403错误).执行上传的源代码在此处(基于以下内容:https://cloud.google.com/storage/docs/access-control#Signing-Strings):

    URL url;
    HttpURLConnection connection;

    try {
        url = new URL("http://google-testbucket.storage.googleapis.com/testdata.txt?GoogleAccessId=1234567890123@developer.gserviceaccount.com&Expires=1331155464&Signature=BClz9e4UA2MRRDX62TPd8sNpUCxVsqUDG3YGPWvPcwN%2BmWBPqwgUYcOSszCPlgWREeF7oPGowkeKk7J4WApzkzxERdOQmAdrvshKSzUHg8Jqp1lw9tbiJfE2ExdOOIoJVmGLoDeAGnfzCd4fTsWcLbal9sFpqXsQI8IQi1493mw%3D");
        connection = (HttpURLConnection) url.openConnection();
        connection.setDoOutput(true);
        connection.setRequestMethod("PUT");

        OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream());
        out.write("Test");
        out.close();

        Log.i("TAG", "PUT Response code: " + connection.getResponseCode());

    } catch (MalformedURLException e) {
        e.printStackTrace();
        Log.e("TAG", "MalformedURLException");
    } catch (ProtocolException e) {
        e.printStackTrace();
        Log.e("TAG", "ProtocolException");
    } catch (IOException e) {
        e.printStackTrace();
        Log.e("TAG", "IOException");
    }

PUT对象的文档:https://cloud.google.com/storage/docs/xml-api/put-object-upload

任何人都可以调查这个问题,并告诉我这个问题可能出现什么问题？

我只是想通过自己HttpURLConnection添加Content-Type标头值application/x-www-form-urlencoded.我在我的android模拟器上使用HTTP嗅探器完成了它.

此自动添加的标头导致签名不匹配.在我更改服务器端的代码以允许与Content-Type: application/x-www-form-urlencoded它的请求生成正确的签名后,它工作正常.

谢谢@ morpheus05的承诺.