java - 为什么我得到 java.io.FileNotFoundException : http://10. 0.2.2 :4000/products/add when trying to send http request?

Question

我试图将 json 发送到我在 NodeJS 中编写的服务器，与服务器建立了连接，出于某种原因，我得到一个 FileNotFoundException，日志:

java.io.FileNotFoundException: http://10.0.2.2:4000/products/add
在 com.android.okhttp.internal.huc.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:255)
在 com.example.myfstrdbcontroller.SendProductJsonTask.doInBackground(SendProductJsonTask.java:39)
在 com.example.myfstrdbcontroller.SendProductJsonTask.doInBackground(SendProductJsonTask.java:21)

我的代码:

public class SendProductJsonTask extends AsyncTask<String, Void, String> {

@Override
protected String doInBackground(String... strings) {
    String data = "";

    HttpURLConnection httpURLConnection = null;
    try {
        httpURLConnection = (HttpURLConnection) new URL(strings[0]).openConnection();
        httpURLConnection.setRequestMethod("POST");

        httpURLConnection.setDoOutput(true);

        DataOutputStream wr = new DataOutputStream(httpURLConnection.getOutputStream());
        wr.writeBytes("PostData="+strings[1]);
        wr.flush();
        wr.close();

        InputStream in = httpURLConnection.getInputStream();
        InputStreamReader inputStreamReader = new InputStreamReader(in);

        int inputStreamData = inputStreamReader.read();

        while (inputStreamData != -1) {

            char current = (char) inputStreamData;

            inputStreamData = inputStreamReader.read();

            data += current;

        }

    } catch (Exception e) {
        Log.d("ccb", "doInBackground16: "+e.getCause());
        Log.d("ccb", "doInBackground17: "+e.getMessage());
        e.printStackTrace();
    } finally {
        if (httpURLConnection != null) {
            httpURLConnection.disconnect();
        }
    }
    return data;
}

@Override
protected void onPostExecute(String s) {
    super.onPostExecute(s);
    Log.d("ccb", "onPostExecute: "+s);
}

我调用http请求的代码:

try {
                productJson(nameOfProduct, serialOfProduct, priceOfProduct, getGenderRB(), uriList, getColorsCB(), getSizeCB(), new JSONMadeListener() {
                    @Override
                    public void onJSONMade(JSONObject object) {
                        try {
                            SSLContext.getInstance("TLSv1.2");
                        } catch (NoSuchAlgorithmException e) {
                            e.printStackTrace();
                        }
                        try {
                            ProviderInstaller.installIfNeeded(getApplicationContext());
                        } catch (GooglePlayServicesRepairableException e) {
                            e.printStackTrace();
                        } catch (GooglePlayServicesNotAvailableException e) {
                            e.printStackTrace();
                        }
                        new SendProductJsonTask().execute("http://10.0.2.2:4000/products/add",object.toString());
                    }
                });
            } catch (JSONException e) {
                e.printStackTrace();
            }

Answer 1

在你的情况下

httpURLConnection.getInputStream();

正在抛出 FileNotFoundException，这意味着您的服务器存在一些问题。

尝试使用 https://www.codepunker.com/tools/http-requests 检查 post 请求是否真的有效.