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Trouble with "inputstream" when creating mobile app that downloads weather information (with AsyncTask)

I'm trying to make a mobile app that downloads info from the openweathermap.org apis. For example, if you feed that app this link: http://api.openweathermap.org/data/2.5/weather?q=Boston,us&appid=fed33a8f8fd54814d7cbe8515a5c25d7 you will get the information about the weather in Boston, MA. My code seems to work up to the point where I have to convert the input stream to a string variable. When I do that, I get garbage. Is there a particular way to do this seemingly simple task in a proper way? Here is my code so far...
private class DownloadWebpageTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... urls) {
// params comes from the execute() call: params[0] is the url.
try {
return downloadUrl(urls[0]);
} catch (IOException e) {
return null;
}
}
// onPostExecute displays the results of the AsyncTask.
#Override
protected void onPostExecute(String result) {
TextView test = (TextView) findViewById(R.id.test);
if(result!=null) test.setText(result);
else{
Log.i(DEBUG_TAG, "returned result is null");}
}
}
private String downloadUrl(String myurl) throws IOException {
InputStream is = null;
try {
URL url = new URL(myurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(10000 /* milliseconds */);
conn.setConnectTimeout(15000 /* milliseconds */);
conn.setRequestMethod("GET");
conn.setDoInput(true);
// Starts the query
conn.connect();
int response = conn.getResponseCode();
Log.i(DEBUG_TAG, "The response is: " + response);
is = conn.getInputStream();
String text = getStringFromInputStream(is);
//JSONObject json = new JSONObject(text);
//try (Scanner scanner = new Scanner(is, StandardCharsets.UTF_8.name())) {
//text = scanner.useDelimiter("\\A").next();
//}
//Bitmap bitmap = BitmapFactory.decodeStream(is);
return text;
}catch(Exception e) {
Log.i(DEBUG_TAG, e.toString());
}finally {
if (is != null) {
is.close();
}
}
return null;
}
private static String getStringFromInputStream(InputStream is) {
BufferedReader br = null;
StringBuilder sb = new StringBuilder();
String line;
try {
br = new BufferedReader(new InputStreamReader(is));
while ((line = br.readLine()) != null) {
sb.append(line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (br != null) {
try {
br.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return sb.toString();
}

Check this library . Is An asynchronous callback-based Http client for Android built on top of Apache’s HttpClient libraries.

IOException error to connect to wamp server with eclipse?

I have a problem with connecting to WAMP server with my android program that I made with eclipse....
This is my class:
public class Webservice {
public static String readurl(String url)
{
try {
HttpClient client = new DefaultHttpClient();
HttpPost method = new HttpPost(url);
HttpResponse response = client.execute(method);
InputStream inputStream = response.getEntity().getContent();
String resault = ConvertInputStream(inputStream);
return resault;
}
catch (ClientProtocolException e) {
//e.printStackTrace();
Log.i("Log", "Protocol");
}
catch (IOException e) {
//e.printStackTrace();
Log.i("Log", "IOException");
}
return "read";
}
private static String ConvertInputStream(InputStream inputStream)
{
try
{
BufferedReader reader = new BufferedReader(new
InputStreamReader(inputStream));
StringBuilder builder = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null)
{
builder.append(line);
}
return builder.toString();
}
catch (IOException e)
{
e.printStackTrace();
}
return null;
}
}
And this is my activity code:
public class NotesActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
String resault = Webservice.readurl("http://localhost/note-server");
Log.i("Log", "Resault: " + resault);
When I run, it gives me "IOException" because of the "Log" in my class under the IOException, and at the end give me "Result: read"!!!!!
How can I fix that?

If you are running on an emulator then you should use 10.0.2.2 instead of localhost.
See this post.

Why can't read this json, but Browser can

I don't understand why can't I read this json link but Browser Chrome can read, I tried with different link and I read them.
this is the link for requesting json response:
My Code:
runOnUiThread(new Runnable() {
#Override
public void run() {
new sendToken().execute("http://admin:123#qlvb-snv.newsaigonsoft.com/push-notifications-portlet/api/secure/jsonws/pushnotificationsdevice/add-push-notifications-device?token=cNAXYNQSPHk:APA91bF86THzkPE_ol9euea1M40x6jVgN9RjUOISVtL-UEXDYpAP62aeRnUwkLrSt6z8C4saTJPKW5CJ57VSRmovZ5OBX4NsZg3U-zoDdXB64dWzAQGB7WllGvqGEO3Nt4_Fbg-vUyok&platform=android");
}
});
and My AsyncTask:
class sendToken extends AsyncTask<String, Integer, String> {
#Override
protected String doInBackground(String... params) {
return docNoiDung_Tu_URL(params[0]);
}
#Override
protected void onPostExecute(String s) {
Log.d("Respones: ", s + "");
}
}
and it does not respond with anything.

Two things may be the cause
either your method
docNoiDung_Tu_URL is not correct or correctly written
or, You have no permissions to access Internet.

change your doInBackground Like this
class sendToken extends AsyncTask<String, Integer, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected String doInBackground(String... params) {
try {
HttpClient httpclient = getNewHttpClient();
HttpGet httpget = new HttpGet(arg0[0]);
// Execute HTTP get Request
HttpResponse response = httpclient.execute(httpget);
HttpEntity entity = response.getEntity();
String responseString = EntityUtils.toString(entity, "UTF-8");
return responseString;
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String s) {
Log.d("Respones: ", s);
}
Also add the dependencies to build.gradle
compile('org.apache.httpcomponents:httpcore:4.4.1') {
exclude group: 'org.apache.httpcomponents', module: 'httpclient'
}
don't forget to add the internet permission to manifest
<uses-permission android:name="android.permission.INTERNET"/>

you have to make http call
HttpURLConnection urlConnection = null;
String My_URL = "YOUR URL";
BufferedReader reader = null;
URL url = null;
String Json;
InputStreamReader inputStream1 = null;
InputStream inputStream = null;
inside do in background
#Override
protected String doInBackground(Void... params) {
try {
url = new URL(My_URL);
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
if(urlConnection.getResponseCode() == 200)
{
inputStream = urlConnection.getInputStream();
Json = readData(inputStream);
}
else {
urlConnection.getResponseCode();
}
}catch (Exception e){
Json = e.toString();
}
finally {
if (urlConnection!=null)
urlConnection.disconnect();
try {
if (inputStream!=null)
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return Json;
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
// your work
}
public String readData(InputStream inputStream)
{
StringBuilder builder = new StringBuilder();
try {
if (inputStream != null) {
inputStream1 = new InputStreamReader(inputStream);
reader = new BufferedReader(inputStream1);
String line = reader.readLine();
while (line != null) {
builder.append(line);
line = reader.readLine();
}
} else {
Toast.makeText(MainActivity.this, "errorwa", Toast.LENGTH_SHORT).show();
}
}catch (Exception e){}
return builder.toString();
}

You can not directly read the response from the url.
Try out below code:
public JSONObject getJSONFromUrl(String url) {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
Add the below permission in manifest
<uses-permission android:name="android.permission.INTERNET"/>

android set data in external database

i would like to write data in an external mysql database with my android app.
this class works for that:
public class SendingData extends AppCompatActivity {
Intent intent = null;
private class LoadingDataURL extends AsyncTask<String, String, JSONArray> {
#Override
protected JSONArray doInBackground(String... params) {
URL url;
HttpURLConnection urlConnection = null;
JSONArray response = new JSONArray();
try {
url = new URL(params[0]);
urlConnection = (HttpURLConnection) url.openConnection();
int responseCode = urlConnection.getResponseCode();
String responseString = readStream(urlConnection.getInputStream());
intent = new Intent(SendingData.this, Overview.class);
startActivity(intent);
response = new JSONArray(responseString);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (urlConnection != null)
urlConnection.disconnect();
}
return response;
}
private String readStream(InputStream in) {
BufferedReader reader = null;
StringBuffer response = new StringBuffer();
try {
reader = new BufferedReader(new InputStreamReader(in, "UTF-8"));
String line = "";
while ((line = reader.readLine()) != null) {
response.append(line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return response.toString();
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.loading_data);
String firstname = "Max";
String secondname= "Mustermann";
LoadingDataURL client = new LoadingDataURL();
client.execute("https://domain.com/index.php?"+
"fristname="+fristname+
"&secondname="+secondname);
}
}
My Problem is, that if in my strings (fristname, secondname) is an & or ? or any special characters, the entry will not be save correctly.
any ideas? :)

Use the URLEncoder class.
Try this please
String fn = URLEncoder.encode(fristname, "utf-8");
String sn = URLEncoder.encode(secondname, "utf-8");
LoadingDataURL client = new LoadingDataURL();
client.execute("https://domain.com/index.php?"+
"fristname=" + fn + "&secondname=" + sn);
Note: Don't encode the full url, just the parameter values.

Getting text from internet

If you go to http://www.elven.ee/ip/ - you can see it gives ip. If you refresh, it gives different port.
How can I get that IP into android? I don't know how to make it also update after like every 5 seconds, but right now I want to know how can i get it into my phone. I want to display it as TextView :).

#mopsled solution did not work for me, so here is mine:
public class TestActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView tv = (TextView) findViewById(R.id.textView1);
String ip = "";
final DefaultHttpClient httpClient = new DefaultHttpClient();
final HttpGet httpGet = new HttpGet("http://www.elven.ee/ip/");
try {
final HttpResponse response = httpClient.execute(httpGet);
if (response.getStatusLine().getStatusCode() == 200) {
ip = getString(response);
}
} catch (final ClientProtocolException e) {
e.printStackTrace();
} catch (final IOException e) {
e.printStackTrace();
}
tv.setText(ip);
}
private static String getString(HttpResponse response) {
final HttpEntity retEntity = response.getEntity();
if (retEntity != null) {
InputStream instream = null;
try {
instream = retEntity.getContent();
} catch (final IllegalStateException ise) {
ise.printStackTrace();
} catch (final IOException ioe) {
ioe.printStackTrace();
}
final String result = convertStreamToString(instream);
return result;
} else {
return "";
}
}
private static String convertStreamToString(final InputStream is) {
final BufferedReader reader = new BufferedReader(new InputStreamReader(is));
final StringBuilder sb = new StringBuilder();
String line = null;
try {
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
} catch (final IOException ioe) {
ioe.printStackTrace();
} finally {
try {
is.close();
} catch (final IOException ioe) {
ioe.printStackTrace();
}
}
return sb.toString().trim();
}
}

EDIT: Fixed code
Try a HTTPURLConnection (a simplified version of an example found here):
StringBuilder content = new StringBuilder();
try {
URL url = new URL("http://www.elven.ee/ip/");
URLConnection urlConnection = url.openConnection();
BufferedReader bufferedReader =
new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
String line;
while ((line = bufferedReader.readLine()) != null) {
content.append(line + "\n");
}
bufferedReader.close();
} catch(Exception e) {
e.printStackTrace();
}
String myIp = content.toString();