Develop Reference

How can i get data from server?

after running the url i am getting data in the following form
[
{
"user_name": "riz",
"gems_available": "10",
"free_gems": "110"
},
{
"match_name": "ausvsind",
"Match_start_time": "2016-03-27 19:00:56",
"season_name": "Mid-Season"
}
]
now i want to get user_name and all the data but unable to do..i am getting this data in the result after running my app but unable to fetch.below i have my java code.please help me where i am wrong.
JSONObject jsonObj = new JSONObject();
jsonObj.put("user_id", "abc#hotmail.com");
jsonArray = new JSONArray();
jsonArray.put(jsonObj);
final HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(USER_URL);
String str = jsonArray.toString().replace("[", "");
String str1 = str.replace("]", "");
httppost.setEntity(new StringEntity(str1.toString()));
resp = httpclient.execute(httppost);
HttpEntity ent = resp.getEntity();
result = EntityUtils.toString(ent);
jsonArray1.put(result);
jsobj = new JSONObject(result);
us1 = jsobj.getString(TAG_USER_NAME);
us2 = jsobj.getString(TAG_GEMS_AVAILABLE);
us3 = jsobj.getString(TAG_GEMS_FREE);

Have a look at Retrofit : it helps you parse JSON into a java POJO automagically and will help you avoid non-differential boilerplate
https://github.com/square/retrofit

When I have to get data from a Json, I always you serialization.
Have a Look at GSON. With it, you have to create model Objects that match the json architecture. After it, you can access all your json attributes easily.

There is another, better way to do this.
Use modern libraries for API calls like Retrofit 2.0 with GSON.
Add Retrofit 2.0 to your project
Read: https://github.com/square/retrofit
Create POJO Object from your JSON
http://www.jsonschema2pojo.org/
select Source type > JSON
select Annotation style > GSON
Create API service interface
Step by step: http://square.github.io/retrofit/

Why are you removing the "[" and "]" characters? Those are part of the JSONArray? If you did not want them there, use a JSONObject instead.
I did not test this, so it will have some issues. Conceptually this should work for you:
JSONObject jsonObj = new JSONObject();
jsonObj.put("user_id", "abc#hotmail.com");
final HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(USER_URL);
httppost.setEntity(new StringEntity(jsonObj.toString()));
resp = httpclient.execute(httppost);
HttpEntity ent = resp.getEntity();
result = EntityUtils.toString(ent);
JSONArray jsonArr = new JSONArray(result);
for (int i = 0; i < jsonArr.length(); i++)
{
JSONObject jobj = jsonArr.getJSONObject(i);
if (jobj.has("user_name"))
{
us1 = jobj.getString("user_name");
}
if (jobj.has("gems_available"))
{
us2 = jobj.getString("gems_available");
}
if (jobj.has("free_gems"))
{
us3 = jobj.getString("free_gems");
}
}

How to parse a specific response of a RESTful WS using JSON

I am learning how to parse a response from a restful web service It is supposed to retreive a JSON string so I can parse it, I am using the apache libs in android. Following some questions here in StackOverflow I do the following:
HttpClient httpClient = new DefaultHttpClient();
HttpGet request = new HttpGet(URL);
ResponseHandler<String> handler = new BasicResponseHandler();
try{
result = httpClient.execute(request, handler); ...
with that I can retreive the result of the WS as this:
"[{\"CodigoRTA\":\"0\",\"MensajeRTA\":\"\",\"Respuesta\":\"[{\\"codigo\\":\\"05\\",\\"nombre\\":\\"ANTIOQUIA\\"},{\\"codigo\\":\\"76\\",\\"nombre\\":\\"VALLE DEL CAUCA\\"}]\"}]"
the thing is that I am trying to parse it with JSONObject and JSONArray without success; When I try to use the JSONObject the errorhandler says that it cannot convert the string into JSONObject, so I look up for an answer or a similar problem and found that if the result starts with [] square brackets represents starting of an JSONArray node and curly bracket {} represents JSONObject, so I try to use this code:
//JSONObject jsonObject = new JSONObject(result);
JSONArray jArray = new JSONArray(result);
for(int i=0; i<jArray.length(); i++) {
JSONObject json_data = jArray.getJSONObject(i);
codeDepartment[i] = json_data.getInt("codigo");
NameDepartment[i] = json_data.getString("nombre");
}
without success either, it now says that "it cannot convert String into JSONArray. So any idea of what can I use? any help would be really appreciated.

Well, it seems that the server response is similar to Json response, the thing is all of the \ that it contains. One thing you could do is to replace or remove 1 of the \ backslash and then try to asign the new value to the JSONArray. Something like this:
result = httpClient.execute(request, handler);
result = result.replace("here the info you want to replace", "here with new values to replace with ");
JSONArray jArray = new JSONArray(result);
hope it help you.

How to Parse from the JSON file? [duplicate]

This question already has answers here:
Sending and Parsing JSON Objects in Android [closed]
(11 answers)
Closed 9 years ago.
I have following objects in JSON file. I have to parse it and store it in a file. What will be the android code for doing this?
{
"result":"ok",
"numbers":
[
{
"First":"first",
"Second":"second",
"Third":"third",
"Fourth":"fourth",
"Fifth":"fifth"
}
]
}
Any one find me getting out of this? I would really appreciate your work.

{ -> json object
"result":"ok",
"numbers":[-> json array
{
Do like this
JSONObject jobject=new JSONObject(jsonString);
JSONArray jarray=Jobject.getJSONArray("numbers");
String result=jobject.getJSONObject("result");
for(int i=0;jarray.length();i++){
String first= jarray.getJSONObject(i).getString("First");
String Second= jarray.getJSONObject(i).getString("Second");
}

{ // json object node
"result":"ok",
"numbers":[// json array numbers
{
"First":"first",
To parse
JSONObject jb = new JSONObject("your json");
String result = (JSONArray)jb.getString("result");
JSONArray jr = (JSONArray)jb.getJSONArray("numbers");
JSONObject jb1= (JSONObject) jr.getJSONObject(0);
String first = jb1.getString("First");
// similarly for second third and fourth
Once you parse you can write the result to a file.
Edit:
Note: Network operation must be done in a background thread. Use Asynctask
try
{
HttpClient httpclient = new DefaultHttpClient();
httpclient.getParams().setParameter(CoreProtocolPNames.PROTOCOL_VERSION, HttpVersion.HTTP_1_1);
HttpGet request = new HttpGet("your json url ");
HttpResponse response = httpclient.execute(request);
HttpEntity resEntity = response.getEntity();
String _response=EntityUtils.toString(resEntity);
}catch(Exception e)
{
e.printStackTrace();
}
Now use _response JSONObject jb = new JSONObject("_response);. Rest all is the same

Try Using the following
import org.json.JSONArray;
import org.json.JSONObject;
JSONObject json = null;
JSONArray jsonArray = null;
String data = null;
json = new JSONObject(response);
data = json.getString("numbers");
jsonArray = new JSONArray(data);
for (int i = 0; i < jsonArray.length(); i++) {
String str =jsonArray.getJSONObject(i).toString();
}

always remember { means object and [ means array so you can proceed with following code in the give
JSONObject firstjobject=new JSONObject(jsonString);
JSONArray firstjarray=firstjobject.getJSONArray("numbers");
String result=firstjobject.getJSONObject("result");
for(int i=0;firstjarray.length();i++){
String first= firstjarray.getJSONObject(i).getString("First");
String Second= firstjarray.getJSONObject(i).getString("Second");
}
here numbers is an array and First,Second etc are the keys for relative data values

String cannot be converted to JSONArray Android

I am trying to extract the long url from Google URL api. Following is code snippet, I am trying to get on with:
` StringBuilder url = new StringBuilder(URL);
url.append(shortUrl);
HttpGet get = new HttpGet(url.toString());
HttpResponse r = client.execute(get);
int status = r.getStatusLine().getStatusCode();
if(status == 200){
HttpEntity e = r.getEntity();
String data = EntityUtils.toString(e);
JSONObject jsonObj = new JSONObject(data);
JSONArray ja = jsonObj.getJSONArray("longUrl");
JSONObject last = ja.getJSONObject(0);
return last;
The function containing code returns a JSON object. In logcat, I am seeing an error org.json.JSONException: Value http://www.google.com/ at longUrl of type java.lang.String cannot be converted to JSONArray
The code is receiving the full url (http://www.google.com) but I am doing something wrong with JSONArray.

Try jsonObj.getString("longUrl") instead of jsonObj.getJSONArray("longUrl"), because "longUrl" is a String not an Array and of course, assign the result in a String instead of a JSONArray.

android:json parsing to decode

I am making an app in which i am getting a string as response from server side. that response is encoded in json. Now my problem is How to do json parsing of the encoded response from server side to decode it..
I am geting the following response from server
["ekjyot#emobx.com","prince6179#gmail.com","facebook_514728069"]
It is in the form of an array.I want to decde it and display as textviws in my another activity.
I am using the following code:
HttpClient client = new DefaultHttpClient();
String getURL = "http://www.ondamove.it/English/mob/profile_friends.php?email="+Login.eMailId+"";
HttpGet get = new HttpGet(getURL);
HttpResponse responseGet = client.execute(get);
HttpEntity resEntityGet = responseGet.getEntity();
if (resEntityGet != null)
{
String s = EntityUtils.toString(resEntityGet);
System.out.println(s);
JSONArray ids = new JSONArray(s);
for(int i=0; i< ids.length(); i++){
System.out.println(ids[]); //print each of the string in json array.
}
but it is giving me the error :
The type of the expression must be an array type but it resolved to JSONArray
how to resolve this issue.
can anyone help me over this?
thanks

You can use JSONTokener to parse JSON documents for example:
String json = "{"
+ " \"query\": \"Pizza\", "
+ " \"locations\": [ 94043, 90210 ] "
+ "}";
JSONObject object = (JSONObject) new JSONTokener(json).nextValue();
String query = object.getString("query");
JSONArray locations = object.getJSONArray("locations");

get your response as string
String jsonResponseString = Sever.getResponse();
JSONArray ids = new JSONArray(jsonResponseString);
for(int i=0; i< ids.length(); i++){
Log.i(TAG, ids[i]); //print each of the string in json array.
}

GSON if you just want to keep it simple. Jackson streaming if you need raw speed.
Or you could always use the built in JSON tools -- but I'd recommend one of these other two.