failed to connect to http Android - android

when the connection is so low i get an exception " failed to connect to : http ......", this is my code, can any one please helps me to avoid the exception.
when the connection is so low i get an exception " failed to connect to : http ......", this is my code, can any one please helps me to avoid the exception
private void parseM3uUrlAndPrepare_new(final String url) {
AsyncTask<String, Integer, String> asyn = new AsyncTask<String, Integer, String>(){
URL the_url;
HttpURLConnection conn;
String filePath = "";
InputStream inputStream;
HttpGet getRequest;
#Override
protected void onPreExecute() {
super.onPreExecute();
try {
the_url = new URL(url);
conn = (HttpURLConnection) the_url.openConnection(Proxy.NO_PROXY);
getRequest = new HttpGet(url);
}
catch (MalformedURLException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
#Override
protected String doInBackground(String... params) {
if(conn != null) {
try {
inputStream = new BufferedInputStream(conn.getInputStream());
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = bufferedReader.readLine()) != null) {
if (line.startsWith("#")) {
}
else if (line.length() > 0) {
filePath = "";
if (line.startsWith("http://")) { // Assume it's a full URL
filePath = line;
}
else { // Assume it's relative
try{
filePath = getRequest.getURI().resolve(line).toString();
}
catch(IllegalArgumentException e){
e.printStackTrace();
}
catch(Exception e){
e.printStackTrace();
}
}
}
}
}
catch (Exception e) {
e.printStackTrace();
}
try {
inputStream.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
return filePath;
}
#Override
protected void onPostExecute(String filePath) {
try {
mediaPlayer.setDataSource(filePath);
DATA_SET = true;
mediaPlayer.prepareAsync(); //this will prepare file a.k.a buffering
}
catch (IllegalArgumentException e) {
e.printStackTrace();
}
catch (IllegalStateException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
};
asyn.execute("");
}

Maybe the problem is the BufferedInputStream. I wrote this code (a long time ago) if you want to try it.
Give an input stream to the fonction and let it work.
import java.io.InputStream;
import java.util.Scanner;
/**
* Created by badetitou.
*/
public class ReadIt {
public static String ReadIt(InputStream is){
return new Scanner(is,"UTF-8").useDelimiter("").next();
}
}

Related

Android java json url from dropbox

I have this piece of code on android that reads data from Assets folder, so I need from this code to read data from external like dropbox. Ho to change and read data from dropbox. thanks
#Override
protected RadioDatas doInBackground(Void... params) {
BufferedReader reader = null;
ArrayList<RadioData> radioDatas = new ArrayList<>();
RadioDatas datas = new RadioDatas();
try {
reader = new BufferedReader(
new InputStreamReader(context.getAssets().open("url.txt"), "Unicode"));
String mLine;
while ((mLine = reader.readLine()) != null) {
RadioData radioData = new RadioData();
String[] meta = mLine.split(";");
radioData.setUrl(meta[0]);
radioData.setTitle(meta[1]);
radioData.setGenres(meta[2]);
radioDatas.add(radioData);
}
} catch (IOException e) {
//log the exception
return null;
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
//log the exception
}
}
}
datas.setRadioDatas(radioDatas);
return datas;
}
This would work....
public class Execute extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... arg0) {
HttpHandler handler = new HttpHandler();
String jsonString = handler.makeServiceCall(json);
if (jsonString != null) {
try {
//parse jsonString
} catch (JSONException e) {
Log.i("Error with parsing", e.getMessage());
}
}
return null;
}
protected void onPostExecute(Void result) {
super.onPostExecute(result);
}
}
You will need a HTTPHandler class...
public class HttpHandler {
private static final String TAG = HttpHandler.class.getSimpleName();
public HttpHandler() {
}
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);
in.close();
} 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) {
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();
}
}
To run it.
new Execute().execute;

Sending Variables to a REST api to be saved on server

I am really struggling with this for some time now and I am really lost in terms of how this works.
I have written a REST service in netbeans and I have passed through Json data and tested that it works using Postman and it is successfully saving to the database.
Now, I want the variables in my mobile application to be sent to that REST api so that they can then be saved to the database.
I have looked at many answers on this but can get none which fully explain to me how to do this.. Ideally I am trying to POST or PUT data from my mobile app into my database.
Here is what I have tried so far:
submit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
details = editTextDetails.getText().toString();
getCurrentDateandTime();
String url = "http://localhost:8080/engAppApi/webservices/engineerTable/";
HttpClient client = new DefaultHttpClient();
HttpPost request = new HttpPost(url);
JSONObject params = new JSONObject();
try {
params.put("machinetype", machineType);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("workordernumber", workOrderNumber);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("employeename", employee);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("activity", activity);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("durationhours", durationHours);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("durationmins", durationMins);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("downtimehours", downTimeHours);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("downtimemins", downTimeMins);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("details", details);
} catch (JSONException e) {
e.printStackTrace();
}
try {
params.put("currentdateandtime", currentDateandTime);
} catch (JSONException e) {
e.printStackTrace();
}
StringEntity jsonEntity = null;
try {
jsonEntity = new StringEntity(params.toString());
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
request = new HttpPost(url);
request.addHeader("Content-Type", "application/json");
request.setEntity(jsonEntity);
try {
HttpResponse response = client.execute(request);
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
can someone please point me in the right direction
Thanks in advance!
just use retrofit 2 for connect to server.
see this link
You have an idea in how to do the post petition, but you have a couple of problems. The first and more important problem is that if you want to retrieve information from a server, you must put your code in an async task. You can't do it in UI Thread. So, i'm gonna share with you a class that implements all the logic you need and you just have to use it. First you need to use gson, look how to use it here
https://github.com/google/gson
and the code is here. It have two methods, one for GET and other for POST.
import android.os.AsyncTask;
import android.util.Log;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
/**
* Created by Administrador on 4/27/2017.
*/
public class JsonReaderFromUrl {
public static final int SUCCESS = 0;
public static final int FAILED = 1;
public static final int PROGRESS = 2;
public interface OnJesonInterface{
void OnJsonReceive(int status, JSONObject jsonObject, int key);
}
public JsonReaderFromUrl() {
}
public void getJsonFromUrlPost(final String url, final OnJesonInterface onJesonInterface, final String body, final int key){
new AsyncTask<Void, String, String>() {
#Override
protected void onPreExecute() {
super.onPreExecute();
onJesonInterface.OnJsonReceive(PROGRESS,null,0);
}
#Override
protected String doInBackground(Void... params) {
if(android.os.Debug.isDebuggerConnected())
android.os.Debug.waitForDebugger();
try {
URL urlJson = new URL(url);
HttpURLConnection connection = (HttpURLConnection) urlJson.openConnection();
connection.setDoInput(true);
connection.setRequestProperty("Content-Type","application/json");
connection.setRequestMethod("POST");
OutputStream outputStream = connection.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
writer.write(body);
writer.flush();
writer.close();
outputStream.close();
connection.connect();
StringBuilder stringBuilder = new StringBuilder();
int httpStatus = connection.getResponseCode();
if (httpStatus == HttpURLConnection.HTTP_CREATED){
BufferedReader br = new BufferedReader(
new InputStreamReader(connection.getInputStream(),"utf-8")
);
String line = "";
while ((line = br.readLine()) != null){
stringBuilder.append(line + "\n");
}
br.close();
return stringBuilder.toString();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
if (s != null){
try {
JSONObject jsonObject = new JSONObject(s);
onJesonInterface.OnJsonReceive(SUCCESS,jsonObject,key);
} catch (JSONException e) {
e.printStackTrace();
}
}
else {
onJesonInterface.OnJsonReceive(FAILED,null,0);
}
}
}.execute();
}
public void getJsonFromUrl(final String url, final OnJesonInterface onJesonInterface){
AsyncTask<Void,String,String> asyncTask = new AsyncTask<Void, String, String>() {
#Override
protected void onPreExecute() {
super.onPreExecute();
onJesonInterface.OnJsonReceive(PROGRESS,null,0);
}
#Override
protected String doInBackground(Void... params) {
try {
URL urlJson = new URL(url);
HttpURLConnection connection = (HttpURLConnection) urlJson.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
StringBuffer stringBuffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null){
stringBuffer.append(line + "\n");
Log.d("RESPONDE JSON: ",">" + line);
}
return stringBuffer.toString();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
if (s != null){
try {
JSONObject jsonObject = new JSONObject(s);
onJesonInterface.OnJsonReceive(SUCCESS,jsonObject,0);
} catch (JSONException e) {
e.printStackTrace();
}
}
else {
onJesonInterface.OnJsonReceive(FAILED,null,0);
}
}
}.execute();
}
}
import this class where you need and use it PD: The key value is an int that can be used to retrieve what response correspond to each petition, this in case you use this class with a lot of petitions.

A connection was leaked

I have a HTTP handler class that will handle the calls to a ASYNC method. Everything works fine, I am able to gather information from the json and display it inside of the application, however, I have noticed that I sometimes get the following in my log.
A connection to http://www.abc123.com/ was leaked. Did you forget to close a response body?
Is there any specific reason why I would be getting this. I am closing in within the try method in convertStreamToString.
public class HttpHandler {
private static final String TAG = HttpHandler.class.getSimpleName();
public HttpHandler() {
}
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) {
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();
}
}

doInBackground throws NullPointerException for no reason

In here the code with BufferedReaderand line = reader.readLine() works
public class WeatherService extends AsyncTask<TaskParams, Void, String> {
private WeatherServiceCallback callback;
private Exception exception;
public WeatherService(WeatherServiceCallback callback) {
this.callback = callback;
}
#Override
protected String doInBackground(TaskParams... params) {
try {
URL url = new URL("http://api.openweathermap.org/data/2.5/weather?lat=" +
params[0].getLat() + "&lon=" + params[0].getLon() +
"&units=" + TaskParams.getUnits() +
"&type=" + TaskParams.getAccuracy() + "&lang=" + TaskParams.getLanguage() +
"&appid=10660a09a9fb335d72f576f7aa1bbe5b");
URLConnection connection = url.openConnection();
InputStream inputStream = connection.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
StringBuilder builder = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
builder.append(line);
}
return builder.toString();
} catch (MalformedURLException e) {
exception = e;
} catch (IOException e) {
exception = e;
}
return null;
}
#Override
protected void onPostExecute(String s)
{
if (s == null && exception != null)
{
callback.serviceFailure(exception);
return;
}
try
{
JSONObject data = new JSONObject(s);
Parameters parameters = new Parameters();
parameters.poopulate(data);
callback.serviceSuccess(parameters);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
I copy-pasted code to other class since it has very similar functionality and now for no reason I'm getting NullPointerException in while ((line = reader.readLine()) != null) and I have no idea why since as I said it's copy-pasted (I only changed URL and object returned if serivce succeeds)
public class PollutionService extends AsyncTask<TaskParams, Void, String>
{
private PollutionServiceCallback callback;
private Exception exception;
private URLConnection connection;
private InputStream inputStream;
private InputStreamReader streamReader;
private BufferedReader reader;
public PollutionService(PollutionServiceCallback callback) {
this.callback = callback;
}
#Override
protected String doInBackground(TaskParams... params) {
try
{
URL url = new URL("http://api.openweathermap.org/pollution/v1/co/" + params[0].getLat() +
"," + params[0].getLon() + "/current.json?&appid=10660a09a9fb335d72f576f7aa1bbe5b");
try
{
connection = url.openConnection();
}
catch (IOException e)
{
exception = new Exception("Connection error");
}
try
{
inputStream = connection.getInputStream();
}
catch (IOException e)
{
exception = new Exception("Input stream error");
}
try
{
streamReader = new InputStreamReader(inputStream);
}
catch (NullPointerException e)
{
exception = new Exception("Input stream reader error");
}
try
{
reader = new BufferedReader(streamReader);
}
catch (NullPointerException e)
{
exception = new Exception("Buffered reader error");
}
StringBuilder builder = new StringBuilder();
String line;
try
{
while ((line = reader.readLine()) != null)
{
builder.append(line);
}
}
catch (IOException e)
{
exception = e;
}
return builder.toString();
}
catch (MalformedURLException e)
{
exception = e;
}
return null;
}
#Override
protected void onPostExecute(String s)
{
if (s == null && exception != null)
{
callback.pollutionServiceFailure(exception);
return;
}
try
{
JSONObject data = new JSONObject(s);
PollutionParameters parameters = new PollutionParameters();
parameters.poopulate(data);
callback.pollutionServiceSuccess(parameters);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
Any clue?
EDIT
This is rewritten code for PollutionActivity. Callback function serviceFailure prints now the URL address on my phone's screen
public class PollutionService extends AsyncTask<TaskParams, Void, String>
{
private PollutionServiceCallback callback;
private Exception exception;
public PollutionService(PollutionServiceCallback callback) {
this.callback = callback;
}
#Override
protected String doInBackground(TaskParams... params) {
try
{
URL url = new URL("http://api.openweathermap.org/pollution/v1/co/" + params[0].getLat() +
"," + params[0].getLon() + "/current.json?&appid=10660a09a9fb335d72f576f7aa1bbe5b");
URLConnection connection = url.openConnection();
InputStream inputStream = connection.getInputStream();
InputStreamReader streamReader = new InputStreamReader(inputStream);
BufferedReader reader = new BufferedReader(streamReader);
StringBuilder builder = new StringBuilder();
String line;
try
{
while ((line = reader.readLine()) != null)
{
builder.append(line);
}
}
catch (IOException e)
{
exception = e;
}
return builder.toString();
}
catch (MalformedURLException e)
{
exception = e;
}
catch (IOException e)
{
exception = e;
}
return null;
}
#Override
protected void onPostExecute(String s)
{
if (s == null && exception != null)
{
callback.pollutionServiceFailure(exception);
return;
}
try
{
JSONObject data = new JSONObject(s);
PollutionParameters parameters = new PollutionParameters();
parameters.poopulate(data);
callback.pollutionServiceSuccess(parameters);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
Debugging showed me that code jumps to exception after
InputStream inputStream = connection.getInputStream();
If you are getting NPE for reader then it means that reader is not getting initialized and going null.Your code is getting crash at line 23 and 89. So I believe that the problem is right at the start somewhere and not at the point itself, may be some object is going null like connection.Since line number is not displayed here.Check null pointer for every object like if (connection!=null). Since the initial data is coming null,maybe input stream or some other data,hence your reader object is not getting initialized.Also check if you are getting value for every object in debug.

Socket Connection Always Null When Connecting To Remote Server

Good day.Im trying to connect to server with socket.Here is my code on how i do it.
private class SocketConnection extends AsyncTask<String, String, String> {
PrintWriter out;
BufferedReader in;
#Override
protected String doInBackground(String... params) {
connect();
try {
out = new PrintWriter(clientSocket.getOutputStream());
in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
} catch (IOException ex) {
System.out.append("error").append("socketcoonection").println();
}
String msg = null;
try {
msg = in.readLine();
} catch (IOException e) {
e.printStackTrace();
}
while (run) {
System.out.append(msg).append("socketcoonection").println();
out.println();
out.flush();
/*try {
msg = in.readLine();
} catch (IOException ex) {
Logger.getLogger(MainActivity.class.getName()).log(Level.SEVERE, null, ex);
}*/
}
return null;
}
}
and here is the connect() method
public void connect() {
try {
clientSocket = new Socket("vaenterprises.org/test.php", 8080);
} catch (UnknownHostException ex) {
} catch (IOException ex) {
}
if (clientSocket != null) {
run = true;
}
}
and this is the server side php code of test.php
echo json_encode("socket working");
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
and the address link is vaenterprises.org/test/php so im trying to connect to it and read the input or output stream or the echo.Whatever i do,i get nullPointerException at System.out.append(msg).append("socketcoonection").println(); and during debug i figured out that its socket which is null...Please tell me what am i doing wrong?

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