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Error when connecting to online database

I am trying to connect to an external database on my server via AsyncTask but Eclipse is showing me an error in the log-
See the error image.
Here is the code I am using-
MainActivity.java:
package com.deltware.newco;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity {
TextView res;
Button btn1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.res = (TextView) this.findViewById(R.id.textView1);
this.btn1 = (Button) this.findViewById(R.id.button1);
this.btn1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
new getAllUsersTask().execute(new Connector());
}
});
}
public void setTextToView(JSONArray json){
String s= "";
for(int i = 0; i<json.length(); i++){
JSONObject jo = null;
try{
jo = json.getJSONObject(i);
s += "Name: " + jo.getString("name") +
"Email: " + jo.getString("email");
}catch(JSONException e){
e.printStackTrace();
}
}
this.res.setText(s);
}
private class getAllUsersTask extends AsyncTask<Connector, Long,JSONArray>{
#Override
protected JSONArray doInBackground(Connector... param) {
return param[0].getAllUsers();
}
#Override
protected void onPostExecute(JSONArray result) {
setTextToView(result);
}
}
}
Connector.java:
package com.deltware.newco;
import java.io.IOException;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.DefaultClientConnection;
import org.apache.http.protocol.DefaultedHttpContext;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import android.util.Log;
public class Connector {
public JSONArray getAllUsers(){
String url = "url to the location of my php file";
HttpEntity httpEntity = null;
try{
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpget = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpget);
httpEntity = httpResponse.getEntity();
}catch(ClientProtocolException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}
JSONArray json = null;
if(httpEntity == null){
try{
String entityResponse = EntityUtils.toString(httpEntity);
Log.e("Entity Response:",entityResponse);
json = new JSONArray(entityResponse);
}catch(JSONException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}
}
return json;
}
}
PHP file:
$query = mysqli_query($db, "SELECT name, email, gender FROM users");
while($row = mysqli_fetch_assoc($query)){
$ouput[] = $row;
}
echo json_encode($ouput);
I am using Eclipse and Android 4.4 KitKat.

How to make a "raw" string out of JSON in Java

I am coding an android app for school atm. i am stock and want to ask you guy to help me.
So far i understand how to use PHP to print data from a MySQL database ready to be parset in Java. Then my code(taken from here: http://www.helloandroid.com/tutorials/connecting-mysql-database)takes the data and converts it into strings i believe.
So my question is: how do i for eksample make and if statement to check if the userdata is correct? i just dont get it!
Here is all my code for the activity(login form) i use:
package com.example.fungi;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ActionBar;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends Activity {
//Intent i = new Intent(getBaseContext(), MainPageActivity.class);
//startActivity(i);
Button login;
EditText username;
EditText password;
TextView lol;
JSONArray jArray;
String result = null;
InputStream is = null;
StringBuilder sb=null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//ActionBar actionBar = getActionBar();
//actionBar.hide();
lol = (TextView) findViewById(R.id.textView1);
login = (Button) findViewById(R.id.loginbutton);
username = (EditText) findViewById(R.id.usernametext);
password = (EditText) findViewById(R.id.passwordtext);
login.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
String usernameget = username.getText().toString();
String passwordget = password.getText().toString();
if(usernameget.contentEquals("")){
username.setText("usernam required");
}else {
if(passwordget.contentEquals("")){
username.setText("password required");
}else {
String userid = username.getText().toString();
Intent intent = new Intent(getBaseContext(), Side.class);
intent.putExtra("sessionid", userid);
startActivity(intent);
}
}
}
});
String result = "";
//the year data to send
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair(result, result));
//http post
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://http://fungi.webatu.com/Index.php");
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
InputStream is = entity.getContent();
}catch(Exception e11){
Log.e("log_tag", "Fejl i HTTP connection "+e11.toString());
}
//convert response to string
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();
result=sb.toString();
}catch(Exception e){
Log.e("log_tag", "Fejl i resultat konvertering "+e.toString());
}
//parse json data
try{
JSONArray jArray = new JSONArray(result);
for(int i=0;i<jArray.length();i++){
JSONObject json_data = jArray.getJSONObject(i);
Log.i("log_tag","id: "+json_data.getInt("id")+
", username: "+json_data.getString("username")+
", password: "+json_data.getString("password")+
", alder: "+json_data.getInt("alder"));
//maybe if statement here?
;
}
}
catch(JSONException e1){
Log.e("log_tag", "Error parsing data "+e1.toString());
}
}
}
thanks in advance!!

I'm not sure about your issue, but I think you want to get some JSON data from a webservice.
Developing to Android, you cannot use network resources on the main thread. So you will need to start a new thread. To reach that, you can use AsyncTask or use the Thread class.
public static JSONArray getJSONArrayFromURL(String url) {
// initialize
InputStream is = null;
String result = "";
JSONArray jArray = null;
Log.d("URL_SEARCH", url);
// http post
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
} catch (Exception e) {
Log.e("log_tag", "Error in http connection " + e.toString());
}
// convert response to string
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "utf-8"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result = sb.toString();
} catch (Exception e) {
Log.e("log_tag", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jArray = new JSONArray(result);
Log.d("URL_SEARCH", "JSON: " + jArray.length());
} catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
}
return jArray;
}

Unable to get the response from JSON

I am new to android. Well what I am trying to do in the following code is making an http request sending to a php file from where json gets the response. In the php file I am trying to show the city names starting from A. Whenever I am running the code I am getting this error: "org.json.jsonexception value doctype of type java.lang.string cannot be converted to jsonarray". All The related Threads are of no help or i am not able to understand the solution given there.
Here is my Java Code
MainActivity.java
package com.list;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.net.ParseException;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity {
JSONArray jArray;
String result = null;
InputStream is = null;
StringBuilder sb=null;
int ct_id;
String ct_name;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView textview1 = (TextView)findViewById(R.id.textView1);
textview1.setText("Erqem");
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
//http post
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://10.0.2.2/city.php");
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection"+e.toString());
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"UTF-8"),8);
sb = new StringBuilder();
sb.append(reader.readLine() + "\n");
String line="0";
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
//paring data
try{
jArray = new JSONArray(result);
JSONObject json_data = new JSONObject();
json_data=null;
for(int i=0;i<jArray.length();i++){
json_data = jArray.getJSONObject(i);
ct_id=json_data.getInt("CITY_ID");
ct_name=json_data.getString("CITY_NAME");
textview1.setText(ct_name);
}
}
catch(JSONException e1){
Toast.makeText(getBaseContext(), "No City Found"+e1.toString() ,Toast.LENGTH_LONG).show();
Log.e("log_tag", "Error converting result "+e1.getMessage() );
} catch (ParseException e1) {
e1.printStackTrace();
}
}
}
php file
<?php
header('Content-type=application/json; charset=utf-8');
mysql_connect("","root","");
mysql_select_db("Deal");
$sql=mysql_query("select * from CITY where CITY_NAME like 'A%'");
while($row=mysql_fetch_assoc($sql))
$output[]=$row;
print(json_encode($output));
mysql_close();
?>
Any Help would be appreciated.Thanks.

maybe you are using incorrect address, please try 10.0.2.2:8080/city.php

Android php+mysql+json error implementing AsyncTask

Im new to Android and I need a little help. I have a class witch values from one table located on remote mysql and its working fine on 2.3 but on 4.x Im getting errors when I start it. I have read somewhere its because I`m not using AsyncTask. I tried to implement it on existing working code but there is one error, so please help because I tried everything to get this to work but no success.
Here is the existing code that works on 2.3
package com.stole.fetchtest;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.net.ParseException;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.Toast;
public class FetchData extends ListActivity {
#SuppressWarnings("unchecked")
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String result = null;
InputStream is = null;
StringBuilder sb = null;
ArrayList<?> nameValuePairs = new ArrayList<Object>();
List<String> r = new ArrayList<String>();
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(
"http://www.url.com/fetch.php");
httppost.setEntity(new UrlEncodedFormEntity(
(List<? extends NameValuePair>) nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.toString(), Toast.LENGTH_LONG)
.show();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "UTF-8"));
sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result = sb.toString();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.toString(), Toast.LENGTH_LONG)
.show();
}
try {
JSONArray jArray = new JSONArray(result);
JSONObject json_data = null;
for (int i = 0; i < jArray.length(); i++) {
json_data = jArray.getJSONObject(i);
r.add(json_data.getString("names"));
}
setListAdapter(new ArrayAdapter<String>(this, R.layout.names_row, r));
} catch (JSONException e1) {
Toast.makeText(getBaseContext(), e1.toString(), Toast.LENGTH_LONG)
.show();
} catch (ParseException e1) {
Toast.makeText(getBaseContext(), e1.toString(), Toast.LENGTH_LONG)
.show();
}
}}
And then I tried to add AsyncTask, according to some tutorials found online, and it`s looking like this:
package com.stole.fetchtest;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.net.ParseException;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.Toast;
public class FetchData extends ListActivity {
String result = null;
InputStream is = null;
StringBuilder sb = null;
ArrayList<?> nameValuePairs = new ArrayList<Object>();
List<String> r = new ArrayList<String>();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
new task().execute();
}
public class task extends AsyncTask<String, String, Void> {
#SuppressWarnings("unchecked")
#Override
protected Void doInBackground(String... params) {
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://www.url.com/fetch.php");
httppost.setEntity(new UrlEncodedFormEntity(
(List<? extends NameValuePair>) nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.toString(),
Toast.LENGTH_LONG).show();
}
try {
BufferedReader reader = new BufferedReader(
new InputStreamReader(is, "iso-8859-1"));
sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result = sb.toString();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.toString(),
Toast.LENGTH_LONG).show();
}
return null;
}
protected void onPostExecute(Void v) {
try {
JSONArray jArray = new JSONArray(result);
JSONObject json_data = null;
for (int i = 0; i < jArray.length(); i++) {
json_data = jArray.getJSONObject(i);
r.add(json_data.getString("naziv"));
}
setListAdapter(new ArrayAdapter(this, R.layout.names_row, r));
} catch (JSONException e1) {
Toast.makeText(getBaseContext(), e1.toString(),
Toast.LENGTH_LONG).show();
} catch (ParseException e1) {
Toast.makeText(getBaseContext(), e1.toString(),
Toast.LENGTH_LONG).show();
}
}
}
}
The error I`m getting is at
setListAdapter(new ArrayAdapter(this, R.layout.names_row, r));
and it says "The constructor ArrayAdapter(FetchData.task, int, List) is undefined"
Thanks!

it should use the activity context not the task context..
setListAdapter(new ArrayAdapter(FetchData.this, R.layout.names_row, r));

Create json object in servlet

I want to send retrieved data from sever to my Android client... I used a json object to do that. Here is my servlet code.
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
public class AvailabilityResponse extends HttpServlet {
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("application/json");
PrintWriter out=response.getWriter();
String br_id;
br_id=request.getParameter("branchname");
try{
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con=DriverManager.getConnection("jdbc:mysql://localhost:8888/atmlivedetails","root","root");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select atmbrno, atmbrname from location_stat where act_brname='"+br_id+"'");
while(rs.next()){
String s = rs.getString("atmbrno");
String t = rs.getString("atmbrname");
JSONObject arrayObj = new JSONObject();
arrayObj.put("atmbrno",s);
arrayObj.put("atmbrname",t);
out.print(arrayObj);
}
rs.close ();
st.close ();
}
catch(Exception e){
out.print(e);
}
}
}
And This is my android side code..
import java.util.ArrayList;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.ClientProtocolException;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.content.Intent;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import android.os.Bundle;
public class CheckAvailability extends Activity{
Button but1,but2;
EditText brName;
TextView txt1;
String text;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.availability);
brName =(EditText)findViewById(R.id.editText1);
but1 = (Button)findViewById(R.id.button5);
but2 = (Button)findViewById(R.id.button6);
txt1 = (TextView)findViewById(R.id.textView3);
but1.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
String result = null;
InputStream is = null;
StringBuilder sb=null;
ArrayList<NameValuePair> postParameters = new ArrayList<NameValuePair>();
postParameters.add(new BasicNameValuePair("branchname", brName.getText().toString()));
//http post
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://10.0.2.2:8080/hello/AvailabilityResponse");
httppost.setEntity(new UrlEncodedFormEntity(postParameters));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection"+e.toString());
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
sb = new StringBuilder();
sb.append(reader.readLine() + "\n");
String line="0";
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
//paring data
String atm_id;
String atm_name;
try{
JSONArray jArray = new JSONArray(result);
JSONObject json_data=null;
for(int i=0;i<jArray.length();i++){
json_data = jArray.getJSONObject(i);
atm_id=json_data.getString("atmbrno");
atm_name=json_data.getString("atmbrname");
//txt1.setText(atm_name);
}
}catch(JSONException e1){
Toast.makeText(getBaseContext(), "No DATA Found", Toast.LENGTH_LONG).show();
}catch (ParseException e1){
e1.printStackTrace();
}
}
});
}
}
but when i run it it always gives me "No DATA Found" Exception...can any one help me???

Your servlet returns only N number of JSON objects. But your giving that response to JSON array it may be the mistake try this code in your servlet
try{
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con=DriverManager.getConnection("jdbc:mysql://localhost:8888/atmlivedetails","root","root");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select atmbrno, atmbrname from location_stat where act_brname='"+br_id+"'");
int i=0;
JSONArray jArray = new JSONArray();
while(rs.next()){
String s = rs.getString("atmbrno");
String t = rs.getString("atmbrname");
JSONObject arrayObj = new JSONObject();
arrayObj.put("atmbrno",s);
arrayObj.put("atmbrname",t);
jArray.add(i,arrayObj);
i++;
}
rs.close ();
st.close ();
out.print(jArray);
}

print the response from server, before processing json string(converting to json object) so that you can track actual reason. U are getting json exception actually.

After writing to the outputstream, you need to close the Printwriter obejct like this.
out.close()

You need to add json-lib-2.4-jdk15.jar file to your project class-path and use following code to create JSON object.
JSONObject jsonData = new JSONObject();
jsonData.put("key1", "value1");
jsonData.put("key2", "value2");
jsonData.put("key3", "value3");
System.out.println("JSON data: "+jsonData.toString());
Console you will get output: JSON data: {"key1":"value1","key2":"value2","key3":"value3"}