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Save json as string when in a URL

In this URL I have a JSON tree that I wish to retrieve as a String so I can use the library I implemented JSON by amirdew. This is the code I have to parse the JSON:
String simpleJsonString = url;
JSON json = new JSON(simpleJsonString);
String firstTag = json.key("extract").index(0).stringValue();
txtinfo.setText(firstTag);
I've tried using HttpsRequest but I couldn't make it:
HttpResponse httpResponse = null;
try {
httpResponse = httpClient.execute(httpPost);
} catch (IOException e) {
e.printStackTrace();
}
HttpEntity httpEntity = httpResponse.getEntity();
try {
is = httpEntity.getContent();
} 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");
System.out.println(line);
}
is.close();
json = sb.toString();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

You are getting an NetworkOnMainThreadException exception because you are trying to make an API call on the UI or Main thread. One shouldn't do any long running operations on UI thread as it is only intended for UI operations. You should either make an API call in AsyncTask or usesSome networking library like Volley or Retrofit.
Check this out for the detailed description of the exception you mentioned.
AsyncTask Implementation Of your code
private class DownloadFilesTask extends AsyncTask<URL, Integer, String> {
protected Long doInBackground(URL... urls) {
HttpResponse httpResponse = null;
try {
httpResponse = httpClient.execute(httpPost);
} catch (IOException e) {
e.printStackTrace();
}
HttpEntity httpEntity = httpResponse.getEntity();
try {
is = httpEntity.getContent();
} 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");
System.out.println(line);
}
is.close();
return sb.toString();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String result) {
showDialog("Downloaded ");
}
}
Hope it helps.

Try this code..
Best way to used retrofit for api calling ..
add below depedency into app level gradle file..
implementation 'com.squareup.okhttp3:logging-interceptor:3.4.1'
implementation 'com.squareup.retrofit2:retrofit:2.3.0'
implementation 'com.squareup.retrofit2:converter-gson:2.3.0'
after that make retrofit object like this way..
public class ApiClient {
private final static String BASE_URL = "https://en.wikipedia.org/w/";
public static ApiClient apiClient;
private Retrofit retrofit = null;
public static ApiClient getInstance() {
if (apiClient == null) {
apiClient = new ApiClient();
}
return apiClient;
}
//private static Retrofit storeRetrofit = null;
public Retrofit getClient() {
return getClient(null);
}
private Retrofit getClient(final Context context) {
HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient.Builder client = new OkHttpClient.Builder();
client.readTimeout(60, TimeUnit.SECONDS);
client.writeTimeout(60, TimeUnit.SECONDS);
client.connectTimeout(60, TimeUnit.SECONDS);
client.addInterceptor(interceptor);
client.addInterceptor(new Interceptor() {
#Override
public okhttp3.Response intercept(Chain chain) throws IOException {
Request request = chain.request();
return chain.proceed(request);
}
});
retrofit = new Retrofit.Builder()
.baseUrl(BASE_URL)
.client(client.build())
.addConverterFactory(GsonConverterFactory.create())
.build();
return retrofit;
}
}
after that define all api that you want to call..
public interface ApiInterface {
#GET("api.php?format=json&action=query&prop=extracts&exintro=&explaintext=&titles=Portugal")
Call<Response> getData();
}
after that in activity call..
ApiInterface apiInterface = ApiClient.getInstance().getClient().create(ApiInterface.class);
Call<Response> responseCall=apiInterface.getData();
responseCall.enqueue(new Callback<Response>() {
#Override
public void onResponse(Call<Response> call, Response<Response> response) {
if (response.isSuccessful() && response.body()!=null && response!=null){
Gson gson=new Gson();
String data=gson.toJson(response.body());
}
}
#Override
public void onFailure(Call<Response> call, Throwable t) {
}
});

no any response when use httpclient in AsyncTask

i want to get data from my server with AsyncTask and then extract some and send to another location and get more info from that
for first section I'm using from this code for run my AsyncTask method and Cancel AsyncTask after some time (for no response...)
new MySecendServer(link, param,mInstagramSession).execute();
final ProgressDialog pd2 = new ProgressDialog(testActivity.this);
pd2.show();
final Timer tm = new Timer();
tm.scheduleAtFixedRate(new TimerTask() {
public void run() {
runOnUiThread(new Runnable() {
public void run() {
count++;
if (count == 30) {
pd2.cancel();
tm.cancel();
new MySecendServer(.....) .cancel(true); }
}
});
}
}, 1, 1000);
then after get data from my server i try to get more info with this code but i don't get any response or exception i test this code in doInBackground And onPostExecute and no any diffrent and no any response
try {
String requestUrl = "https://api.instagram.com/v1/users/";
HttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(requestUrl);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
if (httpEntity == null) {
throw new Exception("Request returns empty result");
}
InputStream stream = httpEntity.getContent();
String response = StringUtil.streamToString(stream);
if (httpResponse.getStatusLine().getStatusCode() != 200) {
throw new Exception(httpResponse.getStatusLine().getReasonPhrase());
}
} catch (Exception ex) {}
now anyone can give me reason or any suggest for do this work ?
thanks
Update :
I found exception here :
HttpResponse httpResponse = httpClient.execute(httpGet);
and message is :
cause NetworkOnMainThreadException (id=831620140512)
Update 2 :
My first AsyncTask
public class MySecendServerClass extends AsyncTask {
private String link="";
private String [][]pparams;
private InstagramUser IG_User;
private InstagramSession IG_Session;
public MySecendServerClass(String link,String [][]params,InstagramSession user){
this.link=link;
this.pparams=params;
this.IG_Session = user;
}
#Override
protected String doInBackground(Object... arg0) {
String data="";
try{
if(pparams!=null){
for(int i=0;i<pparams.length;i++){
if(i!=0){
data+="&";
}
data+=URLEncoder.encode(pparams[i][0],"UTF8")+"="+URLEncoder.encode(pparams[i][1],"UTF8");
}
}
URL mylink=new URL(link);
URLConnection connect=mylink.openConnection();
connect.setDoOutput(true);
OutputStreamWriter wr=new OutputStreamWriter(connect.getOutputStream());
wr.write(data);
wr.flush();
BufferedReader reader=new BufferedReader(new InputStreamReader(connect.getInputStream()));
StringBuilder sb=new StringBuilder();
String line=null;
while((line=reader.readLine())!=null){
sb.append(line);
}
Log.d("sssss",sb.toString());
return sb.toString();
}
catch(Exception ex){
}
return null;
}
#Override
protected void onPostExecute(Object tr) {
super.onPostExecute(tr);
String result = (String)tr;
try{
JSONObject json = new JSONObject(result);
JSONArray jArray = json.getJSONArray("followlist");
JSONObject jObject = jArray.getJSONObject(0);
String client_id=jObject.getString("client_id");
GrtUserProfile(client_id);
}
catch(Exception ex){
}
}
}
Solve Problem With this Code :
public void GrtUserProfile(String Cid) {
String requestUrl= "https://api.instagram.com/v1/users/"+Cid+"/"+"&access_token="+mInstagramSession.getAccessToken();
new HTTPRequestClass().execute(requestUrl);
}
class HTTPRequestClass extends AsyncTask<String, Void, String> {
protected String doInBackground(String... urls) {
try {
String url = urls[0];
HttpGet httpRequest = new HttpGet(url);
HttpClient httpclient = new DefaultHttpClient();
HttpResponse httpResponse = httpclient.execute(httpRequest);
HttpEntity httpEntity = httpResponse.getEntity();
if (httpEntity == null) {
throw new Exception("Request returns empty result");
}
InputStream stream = httpEntity.getContent();
String response = StringUtil.streamToString(stream);
if (httpResponse.getStatusLine().getStatusCode() != 200) {
throw new Exception(httpResponse.getStatusLine().getReasonPhrase());
}
return response;
} catch (Exception e) {
return "";
}
}
protected void onPostExecute(String Response) {
Log.i("Response", Response);
}
}

Instead of using Timer to cancel async task you can set timeout for HttpURLConnection
private class DownloadFilesTask extends AsyncTask<URL, Integer, Boolean> {
protected Boolean doInBackground(URL... urls) {
try {
HttpURLConnection.setFollowRedirects(false);
HttpURLConnection con = (HttpURLConnection) new URL(url).openConnection();
con.setRequestMethod("HEAD");
con.setConnectTimeout(5000); //set timeout to 5 seconds
return (con.getResponseCode() == HttpURLConnection.HTTP_OK);
} catch (java.net.SocketTimeoutException e) {
return false;
} catch (java.io.IOException e) {
return false;
}
}
protected void onProgressUpdate(Integer... progress) {
setProgressPercent(progress[0]);
}
protected void onPostExecute(Boolean result) {
showDialog("Downloaded " + result );
}
}

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();
}
}

post data in json format to php script with java

I'm trying to POST data in JSON format to a script I have running PHP on my webserver. I have found this post: How to send data to a website using httpPost, app crashes.
Using the code he wrote (putting it on a separate thread first) I am able to post data to the PHP script, which accesses it by the $_POST variable. However, I wish to post my data in JSON format. I am guessing it would require me to post a raw stream of data to the server. What functions are available to achieve this? I would also need to post images as a stream of data to the PHP script so I think this solution will also help me in that area.
Additionally, what are the advantages of posting JSON to the server rather than using the method he used?
I am programming the client side in Java in conjunction with the Android SDK.
Any help would be appreciated.

I have a sample example for posting json data .
Have a look at this:
public class LoginActivity extends Activity {
private static final String TAG = "LoginActivity";
private Context mContext;
private Intent mIntent;
private ProgressDialog pdLoading;
private class LoginTask extends AsyncTask<Void, Void, String>
{
private ArrayList<NameValuePair> mParams = new ArrayList<NameValuePair>();
private JSONArray mJArray = new JSONArray();
private JSONObject mJobject = new JSONObject();
private String jsonString = new String();
#Override
protected void onPreExecute() {
super.onPreExecute();
pdLoading.show();
}
#Override
protected String doInBackground(Void... params) {
try {
mJobject.put("userName", "test");
mJobject.put("password", "test");
mJArray.put(mJobject);
mParams.add(new BasicNameValuePair("message", mJArray.toString()));
jsonString = WebAPIRequest.postJsonData("http://putyoururlhere.com/login.php?", mParams);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return null;
}
return jsonString;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
pdLoading.dismiss();
if(result!=null)
{
/* try {
mJobject = new JSONObject(jsonString);
if(mJobject.getString("Success").equals("True"))
{
mJArray = mJobject.getJSONArray("user");
JSONObject mUser = mJArray.getJSONObject(0);
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}*/
Log.e(TAG, jsonString);
}
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initialization();
new LoginTask().execute();
}
private void initialization() {
mContext = this;
mIntent = new Intent();
pdLoading = new ProgressDialog(mContext);
pdLoading.setMessage("loading...");
}
}
and
public class WebAPIRequest {
public static String convertStreamToString(InputStream is)
throws IOException {
if (is != null) {
StringBuilder sb = new StringBuilder();
String line;
try {
BufferedReader reader = new BufferedReader(
new InputStreamReader(is, "UTF-8"));
while ((line = reader.readLine()) != null) {
sb.append(line).append("\n");
}
} finally {
is.close();
}
return sb.toString();
} else {
return "";
}
}
public static String postJsonData(String url, List<NameValuePair> params) {
String response_string = new String();
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
httppost.addHeader("Content-Type", "application/x-www-form-urlencoded");
try {
httppost.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
String paramString = URLEncodedUtils.format(params, HTTP.UTF_8);
String sampleurl = url + "" + paramString;
Log.e("Request_Url", "" + sampleurl);
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
if (response != null) {
InputStream in = response.getEntity().getContent();
response_string = WebAPIRequest.convertStreamToString(in);
}
} catch (Exception e) {
e.printStackTrace();
}
return response_string;
}
}
EDIT :
try,
print_r(json_decode($_POST['message'], true);
or
$data = file_get_contents('php://input');
$json = json_decode($data,true);
I hope it will be helpful !!

What is the most efficient way on Android to call HTTP Web API calls that return a JSON response?

I'm the perfectionist type, I already got web API calls working fine with Google Places API (just as an example), but I feel it's sometimes slow or maybe I'm not doing it right. Some blogs are saying I should use AndroidHttpClient, but I'm not, should I ?
The web API calls i'm using return json and I don't run them on the UI thread, hence using AsyncTask (is AsyncTask the most efficient way to run on background thread or should I use something else ?)
Please see my code and tell me how could it be more efficient in anyway
public static class NearbySearchRequest extends AsyncTask<String, Void, JSONObject>
{
Exception mException = null;
#Override
protected void onPreExecute()
{
super.onPreExecute();
this.mException = null;
}
#Override
protected JSONObject doInBackground(String... params)
{
StringBuilder urlString = new StringBuilder();
urlString.append("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
urlString.append("key=").append(Constants.GOOGLE_SIMPLE_API_KEY);
urlString.append("&location=").append(params[0]);
urlString.append("&sensor=").append("true");
urlString.append("&language=").append("en-GB");
urlString.append("&name=").append(params[1]);
urlString.append("&rankby=").append("distance");
LogHelper.Log(urlString.toString());
HttpURLConnection urlConnection = null;
URL url = null;
JSONObject object = null;
try
{
url = new URL(urlString.toString());
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
InputStream inStream = null;
inStream = urlConnection.getInputStream();
BufferedReader bReader = new BufferedReader(new InputStreamReader(inStream));
String temp, response = "";
while ((temp = bReader.readLine()) != null)
response += temp;
bReader.close();
inStream.close();
urlConnection.disconnect();
object = (JSONObject) new JSONTokener(response).nextValue();
}
catch (Exception e)
{
this.mException = e;
}
return (object);
}
#Override
protected void onPostExecute(JSONObject result)
{
super.onPostExecute(result);
if (this.mException != null)
ErrorHelper.report(this.mException, "Error # NearbySearchRequest");
}
}

The Http engine you're using seems the best choice. Actually any other 3-rd party engines are based either on Apache, either on HttpUrlConnection. I prefer to use Spring for Android as that API provide an abstraction over Http Engine and you don't really need to care how about what API to use based on API level. Or you can use Volley - a very fashionable library.
I would touch however some of your code:
What if there is an exception while reading the stream? Then the stream remains open and also the connection. So I would suggest to have a finally block where the streams and connection is closed no matter if you get an exception or not:
HttpURLConnection urlConnection = null;
URL url = null;
JSONObject object = null;
InputStream inStream = null;
try {
url = new URL(urlString.toString());
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
inStream = urlConnection.getInputStream();
BufferedReader bReader = new BufferedReader(new InputStreamReader(inStream));
String temp, response = "";
while ((temp = bReader.readLine()) != null) {
response += temp;
}
object = (JSONObject) new JSONTokener(response).nextValue();
} catch (Exception e) {
this.mException = e;
} finally {
if (inStream != null) {
try {
// this will close the bReader as well
inStream.close();
} catch (IOException ignored) {
}
}
if (urlConnection != null) {
urlConnection.disconnect();
}
}
JSON parsing: you're using the Android standard way of parsing JSON, but that's not the fastest and easiest to work with. GSON and Jackson are better to use. To make a comparison when it comes for JSON parsers, I would go for Jackson. Here's another SO topic on this comparison.
Don't concatenate strings like that as concatenating strings will create each time another string. Use a StringBuilder instead.
Exception handling (this is anyway a long-debate subject in all programming forums). First of all you have to log it (Use Log class not System.out.printXXX). Then you need to either inform the user: either you toast a message, either you show a label or notification. The decision depends on the user case and how relevant is the call you're making.
These are the topics I see in you code.
EDIT I realize I didn't answer this: is AsyncTask the most efficient way to run on background thread or should I use something else?
The short answer I would give is: if you're supposed to perform a short time lived request, then AsyncTask is perfect. However, if you need to get some data and display it - but you don't want to worry about whether to download again if the screen is rotated and so on, I would strongly recommend using an AsyncTaskLoader and Loaders in general.
If you need to download some big data, then either you use an IntentService or, for heavy-weight operations, DownloadManager.
Enjoy coding!

------Create a Service Handler Class to your Project--------
public class ServiceHandler {
static String response = null;
public final static int GET = 1;
public final static int POST = 2;
public ServiceHandler() {
}
/*
* Making service call
* #url - url to make request
* #method - http request method
* */
public String makeServiceCall(String url, int method) {
return this.makeServiceCall(url, method, null);
}
/*
* Making service call
* #url - url to make request
* #method - http request method
* #params - http request params
* */
public String makeServiceCall(String url, int method,
List<NameValuePair> params) {
try {
// http client
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
// Checking http request method type
if (method == POST) {
Log.e("in POST","in POST");
HttpPost httpPost = new HttpPost(url);
// adding post params
if (params != null) {
Log.e("in POST params","in POST params");
httpPost.setEntity(new UrlEncodedFormEntity(params));
}
Log.e("url in post service",url);
httpResponse = httpClient.execute(httpPost);
} else if (method == GET) {
// appending params to url
Log.e("in GET","in GET");
if (params != null) {
Log.e("in GET params","in GET params");
String paramString = URLEncodedUtils
.format(params, "utf-8");
url += "?" + paramString;
}
Log.e("url in get service",url);
HttpGet httpGet = new HttpGet(url);
httpResponse = httpClient.execute(httpGet);
}
httpEntity = httpResponse.getEntity();
response = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
public String makeServiceCallIMAGE(String url, int method,
List<NameValuePair> params) {
try {
// http client
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
// Checking http request method type
if (method == POST) {
HttpPost httpPost = new HttpPost(url);
// adding post params
if (params != null) {
httpPost.setEntity(new UrlEncodedFormEntity(params));
}
httpResponse = httpClient.execute(httpPost);
} else if (method == GET) {
// appending params to url
if (params != null) {
String paramString = URLEncodedUtils
.format(params, "utf-8");
url += "?" + paramString;
}
HttpGet httpGet = new HttpGet(url);
httpResponse = httpClient.execute(httpGet);
}
httpEntity = httpResponse.getEntity();
response = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
}
--------------AsyncTask For Login------------------
public class Login_Activity extends ActionBarActivity {
//Internet Service
NetworkConnection nw;
ProgressDialog prgDialog;
Boolean netConnection = false;
//
//Login API
String loginURL ="url";
//
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
nw = new NetworkConnection(getApplicationContext());
prgDialog = new ProgressDialog(this);
// Set Cancelable as False
prgDialog.setCancelable(false);
new LoginOperation().execute();
}
private class LoginOperation extends AsyncTask<String, Void, Void> {
String status, message;
#Override
protected void onPreExecute() {
// Set Progress Dialog Text
prgDialog.setMessage("Logging...");
prgDialog.show();
}
#Override
protected Void doInBackground(String... urls) {
if(nw.isConnectingToInternet() == true)
{
try
{
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("method", "ClientesLogin"));
nameValuePairs.add(new BasicNameValuePair("Email", str_Email));
nameValuePairs.add(new BasicNameValuePair("Senha", str_Password));
ServiceHandler sh = new ServiceHandler();
String response = sh.makeServiceCall(loginURL, ServiceHandler.GET,
nameValuePairs);
Log.e("response", response);
JSONObject js = new JSONObject(response);
status = js.getString("status");
Log.e("status",status);
if(status.contains("Fail"))
{
message = js.getString("message");
}
/*else
{
JSONObject jslogin=js.getJSONObject("user_list");
for (int i = 0; i < jslogin.length(); i++) {
}
}*/
}catch(Exception ex){
}
netConnection = true;
}else
{
netConnection = false;
}
return null;
}
#Override
protected void onPostExecute(Void result) {
prgDialog.dismiss();
if(netConnection == false)
{
Toast toast = Toast.makeText(getApplicationContext(),"Internet is not available. Please turn on and try again.", Toast.LENGTH_LONG);
toast.setGravity(Gravity.CENTER, 0, 0);
toast.show();
}
else
{
if(status.contains("Success"))
{
Toast toast = Toast.makeText(getApplicationContext(), "Login Successful", Toast.LENGTH_SHORT);
toast.setGravity(Gravity.CENTER, 0, 0);
toast.show();
Intent i=new Intent(Login_Activity.this,home_page_activity.class);
startActivity(i);
}
else{
Toast toast = Toast.makeText(getApplicationContext(), message, Toast.LENGTH_SHORT);
toast.setGravity(Gravity.CENTER, 0, 0);
toast.show();
}
}
super.onPostExecute(result);
}
}
}
---------------Network Connection class---------------------
public class NetworkConnection {
Context context;
public NetworkConnection(Context context){
this.context = context;
}
public boolean isConnectingToInternet(){
ConnectivityManager connectivity = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity != null)
{
NetworkInfo[] info = connectivity.getAllNetworkInfo();
if (info != null)
for (int i = 0; i < info.length; i++)
if (info[i].getState() == NetworkInfo.State.CONNECTED)
{
return true;
}
}
return false;
}
}
JSONArray main1 = js.getJSONArray("Test 1");
for (int i = 0; i < main1.length(); i++) {
JSONObject jsonObject = main1.getJSONObject(i);