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Why Volley response is received as "[" and not JSON

I am learning about Volley and I don't know why the response from GET method is coming as a single char -> [.
I am using this method to get the JSON response:
public void getJsonMethod() {
// Instantiate the RequestQueue.
RequestQueue queue = Volley.newRequestQueue(context);
// String url = "https://www.w3schools.com/js/myTutorials.txt";
String url = "http://www.google.com"; // with this url I am getting response
// Request a string response from the provided URL.
final StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
System.out.println("Response is: " + response);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
System.out.println("Response is not good" + error.getMessage());
}
});
// Add the request to the RequestQueue.
queue.add(stringRequest);
}
When I am using this link I do get a response but when I try to use some link that contains nothing but JSON like this one my response it "[".
I am calling this method from Activity like this:
GetJsonClass getJson = new GetJsonClass(this);
getJson.getJsonMethod();
Any ideas on what am I doing wrong here?
Answer + code
If anyone will start using Volley maybe this can help him :
as David Lacroix said in his answer, I called stringRequest and notJsonArrayRequest.
Here is how it should have been:
public void getJsonMethod() {
// Instantiate the RequestQueue.
RequestQueue queue = Volley.newRequestQueue(context);
String url = "your url";
JsonArrayRequest jsonObjectRequest = new JsonArrayRequest(url, new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
System.out.println("this is response good" + response);
}
}, new ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
System.out.println("this is response bad" + error);
}
});
queue.add(jsonObjectRequest);
}

See https://developer.android.com/training/volley/request
StringRequest. Specify a URL and receive a raw string in response. See Setting Up a Request Queue for an example.
JsonObjectRequest and JsonArrayRequest (both subclasses of JsonRequest). Specify a URL and get a JSON object or array (respectively) in response.
You should be using a JsonArrayRequest

myTutorials.txt is being served with status code 304 (no proper suffix and MIME type either):
304 Not Modified. If the client has performed a conditional GET request and access is allowed, but the document has not been modified, the server SHOULD respond with this status code. The 304 response MUST NOT contain a message-body, and thus is always terminated by the first empty line after the header fields.
In other terms, what the browser may display is not neccessarily the same what the server has sent. eg. GSON would accept that JSON only with option lenient enabled, because the array has no name.
see RFC 2616.

Parse url with curly brackets in Android App

How can i Parse url with curly brackets like
http://example.com/api/login/{username}/{password} in an android application.
Normal volley post request returns html.But i need JSON.
Integrating Login API in Android App

If I get you right, what you want to do is send a GET request for login.
The following code can help you (it is not recommended to use GET for login, use POST instead. I'm giving a GET ex because that's what your'e asking for):
final TextView mTextView = (TextView) findViewById(R.id.text);
// ...
// Instantiate the RequestQueue.
RequestQueue queue = Volley.newRequestQueue(this);
String url ="http://example.com/api/login/your_username/your_password";
// Request a string response from the provided URL.
StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
// Display the first 500 characters of the response string.
mTextView.setText("Response is: "+ response.substring(0,500));
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
mTextView.setText("That didn't work!");
}
});

Android Json parsing string cannot be converted to json object error

I want to send parameters such as username and password.
I got an error like String cannot be converted to jsonobject.
I dont know what this happening.Anyone pls help me my code is:
JSONObject obj=new JSONObject();
try{
obj.put("username","test");
obj.put("password","test");
} catch (JSONException e) {
}
JsonObjectRequest jsonObjReq = new JsonObjectRequest(Request.Method.POST,
urlJsonObj, obj, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
} catch (JSONException e) {
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
// Adding request to request queue
AppController.getInstance().addToRequestQueue(jsonObjReq,json_obj_req);
}

There is nothing wrong with the way you are creating JSONObject and putting values in it. Make sure the response received is Json, because your onResponse method accepts JSONObject. You could be receiving String value as response, which could not be converted to JSONObject.

It looks like your response is actually a string and not a json object i.e. {"object":"value"} but rather "object:value". You need to sniff your response via either Stetho, Fiddler or reenact your request via Postman (or Fiddler)
======================
This doesn't answer your question, but this will help you tremendously and make your life easier.
Highly recommend using Gson and Retrofit to make HTTP requests and parse Gson objects easily.
https://github.com/google/gson
http://square.github.io/retrofit/

Android Volley JsonObjectRequest returns same response every time on mobile data

I am using Volley JsonObjectRequest to get data from server.
code snippet:
JsonObjectRequest jsObjRequest = new JsonObjectRequest
(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
System.out.println("Response: " + response.toString());
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
// TODO Auto-generated method stub
}
});
But I am getting same JSONObject response every time on mobile data connection.
Note: It's work perfectly on WiFi connection.
Is anyone facing this issue ? any solution ?

#BNK request.setShouldCache(false); worked for me. It's issue of volley cache management.
I assume that, when a request is sent:
It would hit the cache first and send that to onResponse
then when the results come through from the remote server it would provide it to the onResponse
If you use any of the default Request classes implemented in volley(e.g. StringRequest, JsonRequest, etc.), then call setShouldCache(false) right before adding the request object to the volley RequestQueue
request.setShouldCache(false);
myQueue.add(request);
You can also set expiration policy for cache.
See this answer for more details

Android Volley access caching response data

I'm using Volley library to access my server data.Volley has inbuilt caching function.I tried to use that as follows.this out put "CACHED RESPONSE". but i don't know how to access the cached data.
void initHttpCall(){
RequestQueue queue = Volley.newRequestQueue(mcontext);
UOBRequest<RateData> myReq = new UOBRequest<RateData>(Method.GET,
Constants.GET_RATES,
RateData.class,
mlistner,
createMyReqErrorListener()){
#Override
public Map<String, String> getHeaders(){
HashMap<String, String> headers = new HashMap<String, String>();
headers.put("Authorization", getToken());
headers.put("Accept","application/json" );
return headers;
}
};
myReq.setShouldCache(true);
if(queue.getCache().get(Constants.GET_RATES)!=null){
System.out.println("CACHED RESPONSE");
}else{
queue.add(myReq);
}
}
}
This is my response listner and want to get RateData object here.
new Response.Listener<RateData>() {
#Override
public void onResponse(RateData rateData) {
setupCurrencyPager(rateData);
setLastUpdatedTime();
}
});

You misunderstood how Volley's caching system works. The beauty of it is that as a user of Volley, you are unaware of where the response is coming from.
When you add a new request to the RequestQueue, Volley checks if that request already has a cached response. If it does, and that response has not expired yet, it is returned immediately. Otherwise, it goes outside to the network, retrieves the response, caches it and returns it to you.
You don't need that last if statement, simply add it to the queue and Volley will take care of the rest.

try the following code.it will help you sure.
please create a request which you want to pass to server.
JSONObject request = new JSONObject();
request.put("user","user2");
JsonObjectRequest jsObjRequest = new JsonObjectRequest(Request.Method.POST, url, request, new Response.Listener() {
#Override
public void onResponse(JSONObject response) {
// TODO Auto-generated method stub
Log.v("response:-"+response);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
queue.add(jsObjRequest);
}