PHP $_POST is empty or null

PHP $_POST is empty or null - java

I'm desperately trying to solve an issue with my android app. I submit a List to my server with an enum set as a 'tag'. The PHP pages should look at this tag and then proceed to perform the associated functions and return as a json array or object. This works fine with one version of the app but a cloned version fails to fetch data. The PHP just jumps straight over tag checking at the isset tag and tag is not empty conditions so it must be flat out seeing an empty POST or the object I submit doesn't meet some requirement I'm unaware of.
I've looked through so many posts and searched and searched but haven't found a solution. Why would it work for one version of the app but not for the upgraded version, that hasn't made any changes to the methods used for sending data??
So here's what I'm dealing with. To begin with, an AsyncTask takes the objects and passes to a class that handles communication:
private class UpdateJobList extends AsyncTask<User, Void, Boolean> {
private List<Message> messages;
public UpdateJobList() {
super();
messages = new ArrayList<Message>();
}
#Override
protected Boolean doInBackground(User... params){
try {
CloudConnect cConn = new CloudConnect(sAddress);
this.messages = cConn.getAll(params[0]);
return true;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return false;
}
#Override
protected void onPostExecute(Boolean result) {
if (true)
{
handleMessageList(messages);
}
}
}
Using the CloudConnect class to get single Json objects or an array of Objects:
public class CloudConnect {
private String site;
private InputStream is;
private Gson gson;
public CloudConnect(String site) throws MalformedURLException {
this.site = site;
this.gson = new GsonBuilder().setDateFormat("yyyy-MM-dd").create();
is = null;
}
public synchronized Message get(Message m) throws IOException {
Message msg = null;
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(this.site);
post.setEntity(new UrlEncodedFormEntity(validateMessage(m)));
HttpResponse response = client.execute(post);
StatusLine status = response.getStatusLine();
if ( status.getStatusCode() == 200) {
HttpEntity entity = response.getEntity();
is = entity.getContent();
try {
Reader read = new InputStreamReader(is);
String str = (String) gson.fromJson(read, Object.class);
JsonParser parser = new JsonParser();
JsonElement jElem = parser.parse(str);
JsonObject jObject = (JsonObject) jElem;
msg = gson.fromJson(jObject, Message.class);
is.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return msg;
}
public synchronized List<Message> getAll(Message m) throws IOException {
List<Message> mList = new ArrayList<Message>();
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(this.site);
post.setEntity(new UrlEncodedFormEntity(validateMessage(m)));
HttpResponse response = client.execute(post);
StatusLine status = response.getStatusLine();
if ( status.getStatusCode() == 200) {
HttpEntity entity = response.getEntity();
is = entity.getContent();
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
JsonArray jArray = null;
JsonReader jReader = new JsonReader(reader);
jReader.setLenient(true);
JsonParser parser = new JsonParser();
if (parser.parse(jReader).isJsonArray()){
jArray = parser.parse(jReader).getAsJsonArray();
if ( m instanceof User ){
for (JsonElement je : jArray) {
mList.add(gson.fromJson(je, Job.class));
Log.d("json", je.toString());
}
} else if ( m instanceof Job ) {
for (JsonElement je : jArray) {
mList.add(gson.fromJson(je, Update.class));
Log.d("json", je.toString());
}
}
} else {
JsonElement jElem = parser.parse(jReader);
JsonObject jObject = (JsonObject) jElem;
Error msg = null;
msg = gson.fromJson(jObject, Error.class);
mList.add(msg);
}
is.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return mList;
}
And the PHP code that checks for the tag:
if ( isset($_POST['messageType']) && $_POST['messageType'] != "") {
$tag = $_POST['messageType'];
//
//various functions depending on messageType tag here. Such as getUser($email).
//functions appear to work fine if the PHP doesn't find the initial conditions
//false and skips them all.
} else {
$response["success"] = 0;
$response["error"]["errorMsg"] = "Tags are null";
$response["error"]["messageType"] = $tag;
$response["error"]["varDump"] = var_dump($_POST);
echo json_encode($response);
}

Ok, now I get it. You do not have a problem on your Android code but in PHP (I came here because of the TAG Android). I am not an expert in PHP, but remember that isset ($ _POST ['messageType']) returns true only if the payload of your POST request contains something like: messageType=some_value. So you need to check if the value that you passsed to post.setEntity(value) is something in this format.
You can use tools like Fiddler to see the payload of your request and debug properly.

Related

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();
}
}

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);

How to download JSON data in android

I am developing an android application in which first I am sending request to Web service and getting the response status in 0 or 1 format if I get the response as 1 then complete JSON file is loaded.
My question is I want to make an offline app for which I want to download the JSON data from one activity and read that data in different activity with listview displaying title of every downloaded JSON file. After clicking the listview item, JSON data is displayed. And some of the JSON data items contains URL of images I also want to download them and display them in another activity.
I also want to encrypt the downloaded JSON data. Please Help me.
For reference I have attached the JSON file format.
{"test_time":7200,"time_taken":"0","time_left":"7200","score":null,"easy_score":null,"medium_score":null,"hard_score":null,"status":"n","sections":[{"section_id":"196498","section_name":"Reasoning Aptitude","section_no":1,"total_questions":"40","total_minutes":"24","questions":[{"question_id":"61562","question":{"1":{"text":"In a certain code GRANT is written as UOBSH and PRIDE is written as FEJSQ. How is SOLD written in that code?","image":"","imgHeight":"","imgWidth":""}},"correct_ans":{"1":{"text":"EMPT","image":"","imgHeight":"","imgWidth":""}},"rightOption":[],"rightOptionID":"246408","rightOptionNo":"2","anwer_explaination":{"1":{"text":"","image":"http://abc.com/testengine/images/questions/bankpower/image1.Jpeg","imgHeight":304,"imgWidth":212},"2":{"text":" ","image":"","imgHeight":"","imgWidth":""}},"question_time_taken":"10","marked":"0","skipped":"0","answer_id":"1395795","option_choose":"246407","question_status":1,"options":[{"OptionId":"246406","OptionDesc":{"1":{"text":"EPMT","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246407","OptionDesc":{"1":{"text":"TPME","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246408","OptionDesc":{"1":{"text":"EMPT","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246409","OptionDesc":{"1":{"text":"CKNR","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246410","OptionDesc":{"1":{"text":"ETPM","image":"","imgHeight":"","imgWidth":""}}}]},{"question_id":"61563","question":{"1":{"text":"Four of the following five are alike in a certain way and so form a group. Which is the one that does not belong to that group?","image":"","imgHeight":"","imgWidth":""}},"correct_ans":{"1":{"text":"27","image":"","imgHeight":"","imgWidth":""}},"rightOption":[],"rightOptionID":"246414","rightOptionNo":"3","anwer_explaination":{"1":{"text":"Mouse is odd rest are use for storage.","image":"","imgHeight":"","imgWidth":""}},"question_time_taken":"0","marked":"0","skipped":"1","answer_id":"","option_choose":"","question_status":3,"options":[{"OptionId":"246411","OptionDesc":{"1":{"text":"19","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246412","OptionDesc":{"1":{"text":"17","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246413","OptionDesc":{"1":{"text":"13","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246414","OptionDesc":{"1":{"text":"27","image":"","imgHeight":"","imgWidth":""}}},{"OptionId":"246415","OptionDesc":{"1":{"text":"37","image":"","imgHeight":"","imgWidth":""}}}]}

parse all the data using the parser detailed in that link
http://www.androidhive.info/2012/01/android-json-parsing-tutorial/
then Write all the data into a file using the method below , this way ur data is downloaded and saved as a file
public void appendData(String text)
{
File myFile = new File("sdcard/myfile.file");
if (!myFile.exists())
{
try
{
myFile.createNewFile();
}
catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
try
{
//BufferedWriter for performance, true to set append to file flag
BufferedWriter buf = new BufferedWriter(new FileWriter(myFile, true));
buf.append(text);
buf.newLine();
buf.close();
}
catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}

You need to do something like this:
private class PrepareMapTask extends AsyncTask<String, Integer, Boolean>
{
// Initialize with invalid value
private int mPrepareResult = -1;
private String mJsonString = null;
protected Boolean doInBackground(String... urls)
{
mJsonString = downloadFileFromInternet(urls[0]);
if(mJsonString == null /*|| mJsonString.isEmpty()*/)
return false;
JSONObject jObject = null;
try {
jObject = new JSONObject(mJsonString);
JSONArray jsonImageArray = jObject.getJSONArray("imageTarget");
JSONArray jsonUrlArray = jObject.getJSONArray("videoUrls");
JSONArray jsonVideoOrUrlArray = jObject.getJSONArray("videoOrUrl");
if (jsonImageArray == null || jsonUrlArray == null)
return false;
for (int i = 0; i<jsonImageArray.length(); i++){
mapTargetUrl.put(jsonImageArray.get(i).toString(), jsonUrlArray.get(i).toString());
mVideoOrUrl.add(jsonVideoOrUrlArray.get(i).toString());
}
} catch (JSONException e) {
e.printStackTrace();
return false;
}
return true;
}
protected void onPostExecute(Boolean result)
{
}
private String downloadFileFromInternet(String url)
{
if(url == null /*|| url.isEmpty() == true*/)
new IllegalArgumentException("url is empty/null");
StringBuilder sb = new StringBuilder();
InputStream inStream = null;
try
{
url = urlEncode(url);
URL link = new URL(url);
inStream = link.openStream();
int i;
int total = 0;
byte[] buffer = new byte[8 * 1024];
while((i=inStream.read(buffer)) != -1)
{
if(total >= (1024 * 1024))
{
return "";
}
total += i;
sb.append(new String(buffer,0,i));
}
}catch(Exception e )
{
e.printStackTrace();
return null;
}catch(OutOfMemoryError e)
{
e.printStackTrace();
return null;
}
return sb.toString();
}
private String urlEncode(String url)
{
if(url == null /*|| url.isEmpty() == true*/)
return null;
url = url.replace("[","");
url = url.replace("]","");
url = url.replaceAll(" ","%20");
return url;
}
}
Take the data structures as per your json and modify the code.

try {
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpPost httpPostRequest = new HttpPost(URL);
// Set HTTP parameters
/*StringEntity se;
se = new StringEntity(jsonObjSend.toString());*/
jsonObjSend.length();
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(jsonObjSend.length());
nameValuePairs.add(new BasicNameValuePair("data", jsonObjSend.toString()));
// Log.i("jsonObjSend.toString()","jsonObjSend.toString()"+jsonObjSend.toString());
Log.i("HTTPPOST","URL: "+URL);
Log.i("HTTPPOST","Request: "+jsonObjSend.toString());
UrlEncodedFormEntity en=new UrlEncodedFormEntity(nameValuePairs);
en.getContent();
httpPostRequest.getParams().setParameter("http.socket.timeout", new Integer(600000));
httpPostRequest.setEntity(en);
long t = System.currentTimeMillis();
HttpResponse response = (HttpResponse) httpclient.execute(httpPostRequest);
Log.i(TAG, "HTTPResponse received in [" + (System.currentTimeMillis()-t) + "ms]");
Log.i(TAG, httpPostRequest.getRequestLine().getProtocolVersion().toString());
responses = convertEntityToString(response.getEntity(), "UTF-8");
Log.i("HTTPPOST","Responce: "+responses);
Log.i("HTTPPOST","******************");
//Log.i("Encoding",response.getEntity().getContentEncoding().getName());
if (response.equalsIgnoreCase("")) {
webresponse = 1;
} else {
webresponse = 0;
}
} catch (IOException e) {
h.post(new Runnable() {
#Override
public void run() {
pd.dismiss();
AlertNullWebserviceResponce();
}
});
e.printStackTrace();
}

android use asynctask to parse json

I am working on android application and I need to parse my json object with data. How you can see I create JSONParser class and try to use asynctask but there is something wrong and I can't understand where is the problem. Every time I use it resultJSON is null. Hope that you can give me an advice!
public class JSONParser {
private String resultJSON;
public JSONArray getJSON(String url) throws JSONException {
Parser parser = new Parser();
parser.execute(url);
return json;
}
private class Parser extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... urls) {
for (String url : urls) {
StringBuilder builder = new StringBuilder();
HttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
try {
HttpResponse response = client.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) {
HttpEntity entity = response.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(
new InputStreamReader(content));
String line;
while ((line = reader.readLine()) != null) {
builder.append(line);
}
resultJSON = builder.toString();
} else {
Log.e(JSONParser.class.toString(), "Failed to download file");
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
return resultJSON;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
try {
json = new JSONArray(result);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}

Why don't you JSONArray json = new JSONArray(resultJSON); do this on post execute method of async task .
And i will not suggest varevarao way , as it will create extra burden of one thread .

You should use the get() method of the AsyncTask class to retrieve the result of the task. It waits for the task to complete and gets the result (which means it'd be best if you enclose it within a separate thread with a progress dialog or just a background thread).
public JSONArray getJSON(String url) throws JSONException {
Parser parser = new Parser();
parser.execute(url);
resultJSON = parser.get(); // Probably put this in a Thread to avoid spending too much time waiting for a result on the main thread
JSONArray json = new JSONArray(resultJSON);
return json;
}

The problem is fixed. It's an awful workaround but it works. Add this line
while(json==null) {}
after calling the execute method.

Making a POST call to Google Translate with Jersey returns HTTP 404

I'm trying to write a POST call to Google Translate with Jersey 1.5. This is my code:
package main;
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.WebResource;
import com.sun.jersey.core.util.MultivaluedMapImpl;
import javax.ws.rs.core.MultivaluedMap;
public class Main {
private static String GOOGLE_TRANSLATE_URL = "https://www.googleapis.com/language/translate/v2";
private static String translateString(String sourceString, String sourceLanguage, String targetLanguage) {
String response;
Client c = Client.create();
WebResource wr = c.resource(GOOGLE_TRANSLATE_URL);
MultivaluedMap<String, String> params = new MultivaluedMapImpl();
params.add("q", sourceString);
params.add("source", sourceLanguage);
params.add("target", targetLanguage);
params.add("key", "xxxx");
wr.header("X-HTTP-Method-Override", "GET");
response = wr.post(String.class, params);
return response;
}
public static void main(String[] args) {
System.out.println(translateString("Hello", "en", "sv"));
}
}
When I run this, all I get back is this: com.sun.jersey.api.client.UniformInterfaceException: POST https://www.googleapis.com/language/translate/v2 returned a response status of 404.
I've managed to accomplish this with a simple cURL command like so:
curl --header "X-HTTP-Method-Override: GET" -d key=xxxx -d q=Hello -d source=en -d target=sv https://www.googleapis.com/language/translate/v2
Thanks in advance!

I suspect that POST with zero Content-Length is not something a normal HTTP server will accept. The RFC does not define this case, but the main assumption of POST is that you're sending a message body.
Looking at the Google API, they mention the following
You can also use POST to invoke the API if you want to send more data in a single request. The q parameter in the POST body must be less than 5K characters. To use POST, you must use the X-HTTP-Method-Override header to tell the Translate API to treat the request as a GET (use X-HTTP-Method-Override: GET).
This means that instead of adding q, source and target parameters in the URL, you need to do so in the POST body. I'm not familiar with the Jersey API, from a brief look you just need to add params as an explicit second parameter to the .post call, remove the queryParams() call, and set the Content-Length properly.

I think the best and correct way is this
private static final String gurl = "www.googleapis.com";
private static final String gpath = "/language/translate/v2/detect";
public String detectLangGooglePost(String text) throws SystemException {
List<NameValuePair> qparams = new ArrayList<NameValuePair>();
qparams.add(new BasicNameValuePair("key", key));
URI uri;
try {
uri = URIUtils.createURI("https", gurl, -1, gpath, URLEncodedUtils.format(qparams, "UTF-8"), null);
} catch (URISyntaxException e) {
throw new SystemException("Possibly invalid URI parameters", e);
}
HttpResponse response = getPostResponse(uri, text);
StringBuilder builder = getBuilder(response);
String language = getLanguage(builder);
return language;
}
private HttpResponse getPostResponse(URI uri, String text) throws SystemException {
List<NameValuePair> qparams = new ArrayList<NameValuePair>();
qparams.add(new BasicNameValuePair("q", text));
HttpResponse response;
HttpClient httpclient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(uri);
httpPost.addHeader("X-HTTP-Method-Override", "GET");
try {
httpPost.setEntity(new UrlEncodedFormEntity(qparams));
response = httpclient.execute(httpPost);
} catch (Exception e) {
throw new SystemException("Problem when executing Google get request", e);
}
int sc = response.getStatusLine().getStatusCode();
if (sc != HttpStatus.SC_OK)
throw new SystemException("google status code : " + sc);
return response;
}
private StringBuilder getBuilder(HttpResponse response) throws SystemException {
HttpEntity entity = response.getEntity();
if (entity == null)
throw new SystemException("response entity null");
StringBuilder builder = new StringBuilder();
BufferedReader in = null;
String str;
try {
in = new BufferedReader(new InputStreamReader(entity.getContent()));
while ((str = in.readLine()) != null)
builder.append(str);
} catch (IOException e) {
throw new SystemException("Reading input stream of http google response entity problem", e);
} finally {
IOUtils.closeQuietly(in);
}
if (builder.length() == 0)
throw new SystemException("content stream of response entity empty has zero length");
return builder;
}
private String getLanguage(StringBuilder builder) throws SystemException {
JSONObject data = null;
JSONArray detections = null;
String language = null;
JSONObject object = (JSONObject) JSONValue.parse(builder.toString());
if (object == null)
throw new SystemException("JSON parsing builder object returned null");
if (object.containsKey("data") == false)
throw new SystemException("JSONObject doesn't contain data key");
data = (JSONObject) object.get("data");
detections = (JSONArray) data.get("detections");
if (detections == null)
throw new SystemException("JSON detections is null");
JSONObject body = (JSONObject) ((JSONArray) detections.get(0)).get(0);
if (body == null)
throw new SystemException("detections body is null");
if (body.containsKey("language") == false)
throw new SystemException("language key is null");
language = (String) body.get("language");
if (language == null || language.equals(unknown))
throw new SystemException("Google lang detection - resulting language : " + language);
return language;
}

I was able to send very long text like this!
Client:
MultivaluedMap<String,String> formData = new MultivaluedMapImpl();
formData.add("text", text);
WebResource resource = Client.create().resource(getBaseURI()).path("text2rdf");
return resource.type("application/x-www-form-urlencoded").post(String.class, formData);
Server:
#POST
#Produces("text/whatever")
public String textToRdf (
#FormParam("text") String text) {...

I switched to Apache HttpClient 4.x and solved it like this instead:
public class Main {
private static String GOOGLE_TRANSLATE_URL = "https://www.googleapis.com/language/translate/v2";
private static String GOOGLE_API_KEY = "xxxx";
private static String translateString(String sourceString, String sourceLanguage, String targetLanguage) {
String response = null;
// prepare call
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(GOOGLE_TRANSLATE_URL+"?q="+sourceString+"&source="+sourceLanguage+"&target="+targetLanguage+"&key="+GOOGLE_API_KEY);
post.setHeader("X-HTTP-Method-Override", "GET");
try {
// make the call
ResponseHandler<String> responseHandler = new BasicResponseHandler();
response = client.execute(post, responseHandler);
} catch (IOException e) {
// todo: proper error handling
}
return response;
}
public static void main(String[] args) {
System.out.println(translateString("hello", "en", "sv"));
}
}
Don't really know why this works better than Jersey, but it works. Thanks for trying to help!

We Keep Coding

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PHP $_POST is empty or null - java

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