Develop Reference

Exctracting more than one field at time from a JSon file

I was developing a simple application that exctracts some fields of a JSon that tells me in real time what weather is in that exact moment, and I have exctracted only one filed, and I was asking myself: Is it possible to extract more than on field at time?
Here is the the link from where i parse the Json:
https://fcc-weather-api.glitch.me/api/current?lat=35&lon=139
And here's my code:
public class MainActivity extends AppCompatActivity {
Button btnHit;
TextView txtJson;
ProgressDialog pd;
ArrayMap<Integer, String> arrayMap = new ArrayMap<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnHit = (Button) findViewById(R.id.btnHit);
txtJson = (TextView) findViewById(R.id.tvJsonItem);
btnHit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
new JsonTask().execute("https://fcc-weather-api.glitch.me/api/current?lat=35&lon=139");
}
});
}
public class JsonTask extends AsyncTask<String, String, String> {
protected void onPreExecute() {
super.onPreExecute();
pd = new ProgressDialog(MainActivity.this);
pd.setMessage("Please wait");
pd.setCancelable(false);
pd.show();
}
protected String doInBackground(String... params) {
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line + "\n");
Log.d("Response: ", "> " + line);
}
return buffer.toString();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
if (pd.isShowing()) {
pd.dismiss();
}
try {
JSONObject Object = new JSONObject(result);
JSONArray arr = new JSONArray(Object.getString("weather"));
for (int i = 0; i < arr.length(); i++) {
JSONObject jsonPart = arr.getJSONObject(i);
//txtJson.append("main: " + jsonPart.getString("main") + '\n');
arrayMap.put(i, jsonPart.getString("main"));
txtJson.append("main: " + arrayMap.get(i) + '\n');
}
} catch (JSONException e) {
e.printStackTrace();
//txtJson.setText(result);
}
//txtJson.setText(result);
}
}
}

If I understand correctly you want to extract other object alongwith main from the array weather
"weather": [
{
"id": 701,
"main": "Mist",
"description": "mist",
"icon": "https://cdn.glitch.com/6e8889e5-7a72-48f0-a061-863548450de5%2F50n.png?1499366021876"
}
If that is the requirement then you can use the same process like you have done just change the name of the object.
arrayMap.put(i, jsonPart.getString("description"));
or
you can use gson and convert the object in pojo class in one go. Then use the object of the pojo and access the data.
Hope it helps.

Json parsing error: Value <?xml of type java.lang.String cannot be converted to JSONArray [duplicate]

This question already has an answer here:
JSON error "Value at result of type java.lang.String cannot be converted to JSONArray" in android
(1 answer)
Closed 5 years ago.
I am new to programming and I have small problem i am trying to make an app that will use json to read flickr api but i am getting the error mention in the description i was looking around but none of the solutions worked so i came here to ask
public class JSONPareser {
final String TAG = "JSONParser";
public String makeServiceCall(String reqUrl) {
String response = null;
try {
URL url = new URL(reqUrl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
// read the response
InputStream in = new BufferedInputStream(conn.getInputStream());
response = convertStreamToString(in);
} catch (MalformedURLException e) {
Log.e(TAG, "MalformedURLException: " + e.getMessage());
} catch (ProtocolException e) {
Log.e(TAG, "ProtocolException: " + e.getMessage());
} catch (IOException e) {
Log.e(TAG, "IOException: " + e.getMessage());
} catch (Exception e) {
Log.e(TAG, "Exception: " + e.getMessage());
}
return response;
}
private String convertStreamToString(InputStream is) throws UnsupportedEncodingException {
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"UTF-8"),8);
StringBuilder sb = new StringBuilder();
String line;
try {
while ((line = reader.readLine()) != null) {
sb.append(line).append('\n');
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return sb.toString();
}
}
that is my parser class and here is when i am calling json object
public class getData extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
dialog = new ProgressDialog(MainActivity.this);
dialog.setMessage("Please wait");
dialog.setCancelable(false);
dialog.show();
}
#Override
protected Void doInBackground(Void... params) {
String url = "https://api.flickr.com/services/feeds/photos_public.gne";
JSONPareser pareser = new JSONPareser();
String jsonStr = pareser.makeServiceCall(url);
if (jsonStr != null) {
try {
JSONArray jsonArray = new JSONArray(jsonStr);
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject obj = jsonArray.getJSONObject(i);
FlickrModel model = new FlickrModel();
model.setLink(obj.getString("link"));
model.setDescription(obj.getString("description"));
model.setTitle(obj.getString("title"));
model.setAuthor(obj.getString("author"));
model.setTags(obj.getString("tags"));
flickrList.add(model);
}
} catch (final JSONException e) {
Log.e(TAG, "Json parsing error: " + e.getMessage());
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),
"Json parsing error: " + e.getMessage(),
Toast.LENGTH_LONG)
.show();
}
});
}
} else {
Log.e(TAG, "Couldn't get json from server.");
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),
"Couldn't get json from server. Check LogCat for possible errors!",
Toast.LENGTH_LONG)
.show();
}
});
}
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (dialog.isShowing()) {
dialog.dismiss();
}
thank you so much

Your service seens to be returning a XML instead of JSON, see the header

Json object parsing error using http request

I am having an issue when http request is attempted the code that does the parsing works well...i tried to put a sample json string into the variable result and commented out all the code related to http request...i found the code works fine.But when i do a http request it is not working.Thank you in advance.The following is my code
`
public class MainActivity extends AppCompatActivity {
String result = "";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
onclick();
}
public void onclick(){
Asynctaskrunner run = new Asynctaskrunner();
run.execute("http://headers.jsontest.com/");
TextView text = (TextView) findViewById(R.id.textView);
TextView text1 = (TextView) findViewById(R.id.textView2);
final TextView text2= (TextView) findViewById(R.id.textView5);
final TextView text3 = (TextView) findViewById(R.id.textView6);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
JSONObject json = new JSONObject(result);
String name = json.getString("Accept-Language");
String salary = json.getString("Host");
text2.setText(name);
text3.setText(salary);
}catch (Exception e){
e.printStackTrace();
}
}
}
);
}
//-----------------------------------
private class Asynctaskrunner extends AsyncTask<String,Void,Void>{
private String response;
#Override
protected Void doInBackground(String... params) {
try {
URL url = new URL(params[0]);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
InputStream in = new BufferedInputStream(conn.getInputStream());
response=convertStreamToString(in);
} catch (MalformedURLException e) {
Log.e(TAG, "MalformedURLException: " + e.getMessage());
} catch (ProtocolException e) {
Log.e(TAG, "ProtocolException: " + e.getMessage());
} catch (IOException e) {
Log.e(TAG, "IOException: " + e.getMessage());
} catch (Exception e) {
Log.e(TAG, "Exception: " + e.getMessage());
}
result=response;
TextView textView = (TextView) findViewById(R.id.textView4);
return null;
}
private String convertStreamToString(InputStream is) {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line;
try {
while ((line = reader.readLine()) != null) {
sb.append(line).append('\n');
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return sb.toString();
}
}
}`

String name = json.getString("Accept-Language");
the problem is here! JSON response is not returning any value for the Accept-Language key.
This is the response.
{
"X-Cloud-Trace-Context": "8bc66db5c468f43daff9c6a69fa7d0be/11367517399452323805",
"Host": "headers.jsontest.com",
"User-Agent": "Dalvik/2.1.0 (Linux; U; Android 6.0.1; D6503 Build/23.5.A.0.570)"
}
Change it with other key!
String trace = json.getString("X-Cloud-Trace-Context");
String host = json.getString("Host");
String agent = json.getString("User-Agent");

Error Parsing JSON data on executing PHP script

this is my php script
<?php
try{
$con = new PDO('mysql:host=localhost;dbname=pfe'/*info db*/,'root'/*login*/, ''/*mdp*/);
}
catch (Exception $e)
{
die('Erreur : '.$e->getMessage());
}
$msg = $_GET['msg'];
$mail = $_GET['mail'];
$result = $con->prepare("INSERT INTO message ( `msg`, `mail`)
VALUES ('{$msg}', '{$mail}')");
$result->execute();
if($result == true) {
echo '{"query_result":"SUCCESS"}';
}
else{
echo '{"query_result":"FAILURE"}';
}
my script i think is good cause i tried it with my browser it works but with android does not insert the data
and this is java class,
EditText msg,mail;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
msg = (EditText) findViewById(R.id.editText);
mail = (EditText) findViewById(R.id.editText2);
}
public void signup(View v) {
String message = msg.getText().toString();
String email = mail.getText().toString();
Toast.makeText(this, "wait...", Toast.LENGTH_SHORT).show();
new Insertinto(this).execute(message, email);
}
public class Insertinto extends AsyncTask<String, Void, String> {
private Context context;
public Insertinto(Context context) {
this.context = context;
}
protected void onPreExecute() {
}
#Override
protected String doInBackground(String... arg0) {
String msg = arg0[0];
String mail = arg0[1];
String link;
String data;
BufferedReader bufferedReader;
String result;
try {
data = "?msg=" + URLEncoder.encode(msg, "UTF-8");
data += "&mail=" + URLEncoder.encode(mail, "UTF-8");
link = "http://192.168.43.93/dysfonction.php" + data;
URL url = new URL(link);
HttpURLConnection con = (HttpURLConnection) url.openConnection();
bufferedReader = new BufferedReader(new InputStreamReader(con.getInputStream()));
result = bufferedReader.readLine();
return result;
} catch (Exception e) {
return new String("Exception: " + e.getMessage());
}
}
this is json
protected void onPostExecute(String result) {
String jsonStr = result;
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
String query_result = jsonObj.getString("query_result");
if (query_result.equals("SUCCESS")) {
Toast.makeText(context, "Data inserted successfully", Toast.LENGTH_SHORT).show();
} else if (query_result.equals("FAILURE")) {
Toast.makeText(context, "Data could not be inserted", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(context, "Couldn't connect to database.", Toast.LENGTH_SHORT).show();
}
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(context, "Error parsing JSON data.", Toast.LENGTH_SHORT).show();
}
} else {
Toast.makeText(context, "Couldn't get any JSON data.", Toast.LENGTH_SHORT).show();
}
}
}
}
when i execute it show me "Error parsing JSON data" i didn't find where is the pbm.

debug and check the result received in the postExecute(); and from next time paste the logcat as well..

Try to change this to
if($result == true) {
echo '{"query_result":"SUCCESS"}';
}else{
echo '{"query_result":"FAILURE"}';
}
this
if($result == true) {
$data = array(
'query_result' => 'SUCCESS'
);
}else{
$data = array(
'query_result' => 'FAILURE'
);
}
echo json_encode($data);
It seems to be your java code is so clear. So sent response from php code like above may be works.

in the place of
result = bufferedReader.readLine();
use
result = bufferedReader.readLine().toString();

Starting new Activity causes app to crash

I am attempting to start a new Intent inside onPostExecute() method after an AsyncTask. The app always crashes however and there are no error logs. The System.out.println() calls return the expected output.
#Override
protected JSONObject doInBackground(Void... params) {
// TODO: attempt authentication against a network service.
try {
// Use the email address minus the '#' prefix as temp username.
String[] uList = (mEmail.split("#"));
String mUsername = uList[0];
Serverrequest request = new Serverrequest();
JSONObject userObj = request.getJSON(
"http://10.0.2.2:3700/api/login", mUsername, mPassword);
if (userObj != null) {
// Account exists, return user
return userObj;
} else {
System.out.println("Null response");
}
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
// TODO: register the new account here.
JSONObject newUser = new JSONObject();
try {
newUser.put("username", "Charlie");
} catch (JSONException e) {
}
return newUser;
}
#Override
protected void onPostExecute(final JSONObject user) {
try {
mAuthTask = null;
showProgress(false);
System.out.println(user);
String username = user.getString("username");
System.out.println(username);
SharedPreferences prefs = getSharedPreferences("wordsmith", MODE_PRIVATE);
prefs.edit().putString("username", username).apply();
} catch (JSONException e) {
e.printStackTrace();
}
Intent intent = new Intent(LoginActivity.this, StartScreenActivity.class);
intent.putExtra("user", user.toString());
LoginActivity.this.finish();
startActivity(intent);