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Send data(Client_id=1,Staff_id=2) from android application to tomcat server

i want to send data from android application to tomcat java server.
Data is just one is client_id which is 1 and second is staff_id which is 2.
after authenticate the client id and staff id from tomcat show me a toast of success....please help...
Code is here
public class MyAsyncTasks extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
// display a progress dialog for good user experiance
}
#Override
protected String doInBackground(String... params) {
// implement API in background and store the response in current variable
String current = "";
try {
URL url;
HttpURLConnection urlConnection = null;
try {
url = new URL("http://192.168.1.13:8080/digitaldisplay/s/m/data");
urlConnection = (HttpURLConnection) url
.openConnection();
InputStream in = urlConnection.getInputStream();
InputStreamReader isw = new InputStreamReader(in);
int data = isw.read();
while (data != -1) {
current += (char) data;
data = isw.read();
System.out.print(current);
}
// return the data to onPostExecute method
return current;
} catch (Exception e) {
e.printStackTrace();
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
}
} catch (Exception e) {
e.printStackTrace();
return "Exception: " + e.getMessage();
}
return current;
}
#Override
protected void onPostExecute(String s) {
Toast.makeText(Register.this, "success", Toast.LENGTH_SHORT).show();
Log.d("data", s.toString());
// dismiss the progress dialog after receiving data from API
try {
// JSON Parsing of data
JSONArray jsonArray = new JSONArray(s);
JSONObject oneObject = jsonArray.getJSONObject(0);
// Pulling items from the array
client = Integer.parseInt(oneObject.getString("client"));
staff = Integer.parseInt(oneObject.getString("staff"));
} catch (JSONException e) {
e.printStackTrace();
}
} }}

The logic in your code looks off to me. This is the pattern I usually follow when making a REST call from an activity using HttpURLConnection:
try {
String endpoint = "http://192.168.1.13:8080/digitaldisplay/s/m/data";
URL obj = new URL(endpoint);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setRequestMethod("POST"); // but maybe you want GET here...
con.setConnectTimeout(10000);
con.setDoInput(true);
con.setDoOutput(true);
JSONObject inputJSON = new JSONObject();
inputJSON.put("Client_id", 1);
inputJSON.put("Staff_id", 2);
con.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
OutputStream os = con.getOutputStream();
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(os, "UTF-8"));
writer.write(inputJSON.toString());
writer.flush();
writer.close();
os.close();
int responseCode = con.getResponseCode();
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
System.out.println(response);
} catch (SocketTimeoutException se) {
// handle timeout exception
responseCode = -1;
} catch (Exception e) {
// handle general exception
responseCode = 0;
}
The only major change in adapting the above code for GET would be that you wouldn't write your input data to the connection. Instead, you would just append query parameters to the URL. I am possibly guessing that you need POST here, since your URL doesn't have any query parameters in it.

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.

Run code in AsyncTask stucking UI

I'm trying a copule of days to figure it out, without success,
Target: get use country by IP using asyncTask without stucking UI, and save it into string parm.
Problem: The UI doen't move until the asyncTask finish it job :/
MainActivity ,onCreate method:
.......
JSONObject jsonObject;
try {
jsonObject = new getJSONObjectFromURL(LoginActivity.this).execute("http://ip-api.com/json").get();
if (jsonObject != null) {
if (!jsonObject.getString("status").equals("success"))
throw new InterruptedException();
Log.d(TAG, "onCreate: jsonObject.tostring:" + jsonObject.toString());
countryLocation = jsonObject.getString("country");
Log.d(TAG, "onCreate: countryByIP " + countryLocation);
}
if (!isNetworkAvailable()/* || countryLocation == null*/)
Toast.makeText(MainActivity.this, "Please enable data.", Toast.LENGTH_SHORT).show();
//in button click redo all that code for no internet connection,.
} catch (InterruptedException | ExecutionException | JSONException e) {
e.printStackTrace();
}
asyncTask:
public class getJSONObjectFromURL extends AsyncTask<Object, Object, JSONObject> {
private Context context;
public getJSONObjectFromURL(Context context) {
this.context = context;
}
#Override
protected JSONObject doInBackground(Object... params) {
HttpURLConnection urlConnection = null;
URL url = null;
try {
url = new URL((String) params[0]);
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setReadTimeout(10000 /* milliseconds */);
urlConnection.setConnectTimeout(15000 /* milliseconds */);
urlConnection.setDoOutput(true);
urlConnection.connect();
BufferedReader br = new BufferedReader(new InputStreamReader(url.openStream()));
String jsonString;
StringBuilder sb = new StringBuilder();
String line;
while ((line = br.readLine()) != null) {
sb.append(line + "\n");
}
br.close();
jsonString = sb.toString();
return new JSONObject(jsonString);
} catch (JSONException | IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(JSONObject result) {
//Update the String..
}
}
Everything works perfect, i get the Json, able to read the Country from it, but MainActivity waiting for the onPostExecute to continue.

You are running your AsyncTask in a synchrounous state.
jsonObject = new getJSONObjectFromURL(LoginActivity.this).execute("http://ip-api.com/json").get();
By calling get() you are waiting until the Task has finished it's job. Do not use get() if you want to have a truly asynchronous process. You can use a callback to get notified.

Perform AsyncTask on Android / Posting JSON

I am working on an android app, and am running into some troubles with registering users. I want to post a JSON object to my server and receive one back. I can successfully create a JSON object with the right information but when I go to post it I get a NetworkOnMainThreadException or my HttpClient class returns null when it should be returning a JSONObject and I am very confident that my web server works correctly. I understand that you cannot connect to the network on the main thread and have created an HttpClient class that uses AsnycTask (although probably not correctly). I have been working on this for quite a while and would appreciate any guidance in the right direction.
//Main activity
#Override
public void onClick(View arg0) {
if(!(isEmpty(name) || isEmpty(username) || isEmpty(password) || isEmpty(email))) {
user = new JSONObject();
try {
user.put("username", username.getText().toString());
user.put("name", name.getText().toString());
user.put("email", email.getText().toString());
user.put("password", password.getText().toString());
} catch (JSONException e) {
e.printStackTrace();
}
jRegister = new JSONObject();
try {
jRegister.put("apiToken", Utilities.apiToken);
jRegister.put("user", user);
Log.i("MainActivity", jRegister.toString(2));
} catch (JSONException e) {
e.printStackTrace();
}
//
HttpClient client = new HttpClient(url, jRegister);
result = client.getJSONFromUrl();
try {
if(result != null)
tv.setText(result.toString(2));
else
tv.setText("null");
} catch (JSONException e) {
e.printStackTrace();
}
}else {
tv.setText("");
}
}
HttpClient Class
public class HttpClient extends AsyncTask<Void, Void, JSONObject>{
private final String TAG = "HttpClient";
private String URL;
private JSONObject jsonObjSend;
private JSONObject result = null;
public HttpClient(String URL, JSONObject jsonObjSend) {
this.URL = URL;
this.jsonObjSend = jsonObjSend;
}
public JSONObject getJSONFromUrl() {
this.execute();
return result;
}
#Override
protected JSONObject doInBackground(Void... params) {
try {
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpPost httpPostRequest = new HttpPost(URL);
StringEntity se;
se = new StringEntity(jsonObjSend.toString());
// Set HTTP parameters
httpPostRequest.setEntity(se);
httpPostRequest.setHeader("Accept", "application/json");
httpPostRequest.setHeader("Content-type", "application/json");
long t = System.currentTimeMillis();
HttpResponse response = (HttpResponse) httpclient.execute(httpPostRequest);
Log.i(TAG, "HTTPResponse received in [" + (System.currentTimeMillis()-t) + "ms]");
HttpEntity entity = response.getEntity();
if (entity != null) {
// Read the content stream
InputStream instream = entity.getContent();
// convert content stream to a String
String resultString= convertStreamToString(instream);
instream.close();
resultString = resultString.substring(1,resultString.length()-1); // remove wrapping "[" and "]"
JSONObject jsonObjRecv = new JSONObject(resultString);
// Raw DEBUG output of our received JSON object:
Log.i(TAG,"<JSONObject>\n"+jsonObjRecv.toString()+"\n</JSONObject>");
return jsonObjRecv;
}
}
catch (Exception e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(JSONObject jObject) {
result = jObject;
}
private static String convertStreamToString(InputStream is) {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line = null;
try {
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return sb.toString();
}
}

I understand that you cannot connect to the network on the main thread
and have created an HttpClient class that uses AsnycTask (although
probably not correctly).
You are right you have not implemented it the right way.
In your onClick events (still on Main thread) you performed a network activity causing the error:
HttpClient client = new HttpClient(url, jRegister);
result = client.getJSONFromUrl();
Instead you should run the network operation inside of the AsnycTask
public class GetJsonTask extends AsyncTask<Void, Void, JSONObject >{
private String URL;
private JSONObject jsonObjSend;
public GetJsonTask(String URL, JSONObject jsonObjSend) {
this.URL = URL;
this.jsonObjSend = jsonObjSend;
}
#Override
protected JSONObject doInBackground(Void... params) {
JSONObject jsonObjRecv;
try {
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpPost httpPostRequest = new HttpPost(URL);
StringEntity se;
se = new StringEntity(jsonObjSend.toString());
// Set HTTP parameters
httpPostRequest.setEntity(se);
httpPostRequest.setHeader("Accept", "application/json");
httpPostRequest.setHeader("Content-type", "application/json");
long t = System.currentTimeMillis();
HttpResponse response = (HttpResponse) httpclient.execute(httpPostRequest);
Log.i(TAG, "HTTPResponse received in [" + (System.currentTimeMillis()-t) + "ms]");
HttpEntity entity = response.getEntity();
if (entity != null) {
// Read the content stream
InputStream instream = entity.getContent();
// convert content stream to a String
String resultString= convertStreamToString(instream);
instream.close();
resultString = resultString.substring(1,resultString.length()-1); // remove wrapping "[" and "]"
jsonObjRecv = new JSONObject(resultString);
// Raw DEBUG output of our received JSON object:
Log.i(TAG,"<JSONObject>\n"+jsonObjRecv.toString()+"\n</JSONObject>");
}
}
catch (Exception e) {
e.printStackTrace();
}
return jsonObjRecv;
}
protected void onPostExecute(JSONObject result) {
try {
if(result != null)
tv.setText(result.toString(2));
else
tv.setText("null");
} catch (JSONException e) {
e.printStackTrace();
}
}else {
tv.setText("");
}
}
}
Then you call your async in onclik method like this:
public void onClick(View arg0) {
//.......
GetJsonTask client = new GetJsonTask(url, jRegister);
client.execute();
}

One problem in your code is that your expectations of AsyncTask aren't quite right. In particular this function:
public JSONObject getJSONFromUrl() {
this.execute();
return result;
}
AsyncTask runs the code in the doInBackground() function in a separate thread. This means that once you call execute() you have two parallel lines of execution. You end up with what's called a Race Condition. When you reach the return result line, a couple of things can be happening:
doInBackground() hasn't run and therefore result is still has the default value. In this case null.
doInBackground() can be in the middle of the code. In your particular case because it doesn't modify result then this doesn't affect you much. But it could be on any line (or middle of a line sometimes if operations aren't atomic) when that return happens.
doInBackground() could've finished, but since onPostExecute() runs on the UI thread it has to wait until your onClick handler is finished. By the time onPostExecute() has a chance to run onClick already tried to update tv with whatever it was that getJSONFromUrl returned, most likely null.
The way to set up tasks with AsyncTask is to give it the information it needs to do it's work, start it up with execute, and since you can't know how long it will take to complete, let it handle the finishing steps of the task.
This means that after calling execute you don't wait around for it's result to update views (like in your case), but rather rely on the AsyncTask's onPostExecute or related methods to take over the next steps.
For your case this would mean that your onPostExecute should look something like:
protected void onPostExecute(JSONObject result) {
try {
if(result != null)
tv.setText(result.toString(2));
else
tv.setText("null");
} catch (JSONException e) {
e.printStackTrace();
}
}

reading JSON data from URL

I am trying to parse some JSON data, but my app doesn't do anything because i can't seem to get any response from URL, i tried to open URL connection in few different ways, but it's still the same. for Example :
urlMy=new URL(string);
URLConnection tc = urlMy.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
tc.getInputStream()));
String line=in.readLine();
doesn't return anything, it even dismisses everything in my function written below that code.
Or
urlMy=new URL(examp);
InputStream inputStream = urlMy.openConnection().getInputStream();
InputStreamReader reader = new InputStreamReader(inputStream);
BufferedReader bR = new BufferedReader(reader);
the same thing. This function is called and like it never happend, every function after this one executes, so it's not in the endless loop, but every bit of code in this function after this example code is ignored. if i remove this code for reading url, everthing else works.

Try to use AsyncTask,try something like:
class MyAsyncTask extends AsyncTask<String, String, Void> {
private ProgressDialog progressDialog = new ProgressDialog(MainActivity.this);
InputStream inputStream = null;
String result = "";
protected void onPreExecute() {
progressDialog.setMessage("Downloading your data...");
progressDialog.show();
progressDialog.setOnCancelListener(new OnCancelListener() {
public void onCancel(DialogInterface arg0) {
MyAsyncTask.this.cancel(true);
}
});
}
#Override
protected Void doInBackground(String... params) {
String url_select = "http://yoururlhere.com"
ArrayList<NameValuePair> param = new ArrayList<NameValuePair>();
try {
// Set up HTTP post
// HttpClient is more then less deprecated. Need to change to URLConnection
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url_select);
httpPost.setEntity(new UrlEncodedFormEntity(param));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
// Read content & Log
inputStream = httpEntity.getContent();
} catch (UnsupportedEncodingException e1) {
Log.e("UnsupportedEncodingException", e1.toString());
e1.printStackTrace();
} catch (ClientProtocolException e2) {
Log.e("ClientProtocolException", e2.toString());
e2.printStackTrace();
} catch (IllegalStateException e3) {
Log.e("IllegalStateException", e3.toString());
e3.printStackTrace();
} catch (IOException e4) {
Log.e("IOException", e4.toString());
e4.printStackTrace();
}
// Convert response to string using String Builder
try {
BufferedReader bReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"), 8);
StringBuilder sBuilder = new StringBuilder();
String line = null;
while ((line = bReader.readLine()) != null) {
sBuilder.append(line + "\n");
}
inputStream.close();
result = sBuilder.toString();
} catch (Exception e) {
Log.e("StringBuilding & BufferedReader", "Error converting result " + e.toString());
}
} // protected Void doInBackground(String... params)
protected void onPostExecute(Void v) {
//parse JSON data
try{
JSONArray jArray = new JSONArray(result);
for(i=0; i < jArray.length(); i++) {
JSONObject jObject = jArray.getJSONObject(i);
String name = jObject.getString("name");
String tab1_text = jObject.getString("tab1_text");
int active = jObject.getInt("active");
} // End Loop
this.progressDialog.dismiss();
} catch (JSONException e) {
Log.e("JSONException", "Error: " + e.toString());
} // catch (JSONException e)
} // protected void onPostExecute(Void v)
} //class MyAsyncTask extends AsyncTask<String, String, Void>

In the last Google I/O, Google released a new library called Volley. It's fast for HTTP requests, very easy to use and you can set it up to return JSONObjects ready for parsing. https://developers.google.com/events/io/sessions/325304728