仅在Android中使用Wi-Fi时才发生FileNotFoundException

Question

我的http POST请求在模拟器和真实设备上都能正常工作。在我的几个朋友中，http请求仅适用于移动数据。这个朋友有一个“华为荣誉X6”。他很远，所以我不能在android studio中用他的手机调试。

我得到的唯一信息是，在WIFI上，该请求引发了IOException：

• e.getLocalizedMessage（）：http://134.256.74.200/FactFolder/sendFact.php

• e.fillInStackTrace（）：java.io.FileNotFoundException：http://134.256.74.200/FactFolder/sendFact.php

我真的不明白为什么在移动数据上一切正常，但在WIFI上却无法正常工作。 是因为手机型号吗？

清单：

<?xml version="1.0" encoding="utf-8"?>

<!-- Include required permissions for Google Mobile Ads to run. -->
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

<application
    android:allowBackup="true"
    android:icon="@drawable/logo_blue"
    android:label="@string/app_name"
    android:roundIcon="@drawable/logo_blue_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme"> <!-- This meta-data tag is required to use Google Play Services. -->
    <meta-data
        android:name="com.google.android.gms.version"
        android:value="@integer/google_play_services_version" />

    <activity
        android:name=".MainActivity"
        android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity> <!-- Include the AdActivity configChanges and theme. -->
    <activity
        android:name="com.google.android.gms.ads.AdActivity"
        android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"
        android:theme="@android:style/Theme.Translucent" />

    <activity android:name=".InfoActivity"
        android:screenOrientation="portrait" />
    <activity android:name=".SendFactActivity"
        android:windowSoftInputMode="adjustPan"
        android:screenOrientation="portrait" />

    <receiver android:name=".FactWidget">
        <intent-filter>
            <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
        </intent-filter>

        <meta-data
            android:name="android.appwidget.provider"
            android:resource="@xml/fact_widget_info" />
    </receiver>

    <activity android:name=".FactWidgetConfigureActivity">
        <intent-filter>
            <action android:name="android.appwidget.action.APPWIDGET_CONFIGURE" />
        </intent-filter>
    </activity>


    <service android:name=".RebootService"/>

    <receiver
        android:enabled="true"
        android:exported="true"
        android:name=".StartServiceOnStartup"
        android:permission="android.permission.RECEIVE_BOOT_COMPLETED">

        <intent-filter>
            <action android:name="android.intent.action.BOOT_COMPLETED" />
            <action android:name="android.intent.action.QUICKBOOT_POWERON" />
            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>

    </receiver>


</application>

请求：

private class SendFact extends AsyncTask<String, Integer, String> {

    @Override
    protected String doInBackground(String... params) {

        String login_url = "http://" + IP_ADDRESS + "/FactFolder/sendFact.php";
        try {

            String fact = params[0];
            String owner = params[1];
            String socialMediaType = params[2];
            String socialMediaName = params[3];

            URL url = new URL(login_url);
            HttpURLConnection con = (HttpURLConnection) url.openConnection();
            con.setRequestMethod("POST");
            con.setDoOutput(true);
            con.setDoInput(true);


            OutputStream outputStream = con.getOutputStream();
            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
            String post_data = URLEncoder.encode("fact", "UTF-8")+"="+ URLEncoder.encode(fact, "UTF-8")+"&"+
                    URLEncoder.encode("owner", "UTF-8")+"="+ URLEncoder.encode(owner, "UTF-8")+"&"+
                    URLEncoder.encode("socialmediatype", "UTF-8")+"="+ URLEncoder.encode(socialMediaType, "UTF-8")+"&"+
                    URLEncoder.encode("socialmedianame", "UTF-8")+"="+ URLEncoder.encode(socialMediaName, "UTF-8");
            writer.write(post_data);
            writer.flush();
            writer.close();
            outputStream.close();


            InputStream inputStream = con.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1")); //iso-8859-1
            String result = "";
            result += reader.readLine();
            reader.close();
            inputStream.close();
            con.disconnect();
            return result;
        } catch (MalformedURLException e) {
            return e.getMessage();
        } catch (IOException e) {
            return e.getMessage();
        }
    }

    @Override
    protected void onPostExecute(String result) {
        sendFact_finish(result);
    }

    @Override
    protected void onPreExecute() {}
}