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put not working on android Volley org.json.JSONException: End of input at character 0 of

I sent request with postman its working, but volley doesn't work. I always get error! I searched stackoverflow volley returns error when response is empty but i added CustomJsonObjectRequest still the issue remains.
Error message
Volley org.json.JSONException: End of input at character 0 of
CustomJsonObjectRequest
public class CustomJsonObjectRequest extends JsonObjectRequest {
public CustomJsonObjectRequest(int method, String url, JSONObject jsonRequest, Response.Listener<JSONObject> listener, Response.ErrorListener errorListener) {
super(method, url, jsonRequest, listener, errorListener);
}
#Override
protected Response<JSONObject> parseNetworkResponse(NetworkResponse response) {
try {
if (response.data.length == 0) {
byte[] responseData = "{}".getBytes("UTF8");
response = new NetworkResponse(response.statusCode, responseData, response.headers, response.notModified);
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return super.parseNetworkResponse(response);
}
}
Volley request
EcoElement ecoElement = ecoElementArrayList.get(position);
Map<String, String> params = new HashMap<String, String>();
params.put("Id", ecoElement.getId().toString());
params.put("Checked", ecoElement.getChecked().toString());
JSONObject ObjParams = new JSONObject(params);
try {
CustomJsonObjectRequest getRequest = new CustomJsonObjectRequest(Request.Method.PUT, "https://ourwebsite.sslbeta.de/api/gardenapi/updateecoelements", ObjParams,
response -> {
Toast.makeText(getContext(), ""+response, Toast.LENGTH_SHORT).show();
progressBar.setVisibility(View.GONE);
},
error -> {
Toast.makeText(getContext(), ""+error.toString(), Toast.LENGTH_SHORT).show();
progressBar.setVisibility(View.GONE);
}
);
RequestQueueSingleton.getInstance(getContext()).addToRequestQueue(getRequest);
} catch (Exception e) {
Toast.makeText(getContext(), e.toString(), Toast.LENGTH_LONG).show();
}

Finally i was able to fix the issues after hours of searching. There were two reasons to this, first is that api was returning null/empty so CustomJsonObjectRequest fixed that, and then another issue is that i forgot to add authentication headers. that was a silly mistake i know!
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
HashMap<String, String> headers = new HashMap<String, String>();
headers.put("Content-Type", "application/json");
headers.put("Authorization", "Bearer "+access_token);
return headers;
}
};

Here is the solution, just create this method and pass your value.
private void CustomJsonObjectRequest() {
String tag_string_req = "req__details";
StringRequest strReq = new StringRequest(Request.Method.POST, <API URL>, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
getPerspective().showErrorLogs(TAG, "Response Invest : " + response);
try {
// Parse your response here
} catch (Exception e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
params.put("Id", <ID VALUE HERE>);
params.put("Checked", <TRUE or FALSE>);
return params;
}
};
strReq.setRetryPolicy(new RetryPolicy() {
#Override
public void retry(VolleyError arg0) throws VolleyError {
}
#Override
public int getCurrentTimeout() {
return 0;
}
#Override
public int getCurrentRetryCount() {
return 0;
}
});
strReq.setShouldCache(false);
addToRequestQueue(strReq, tag_string_req);
}
Both ID and Checked must have String type.And create below methods in MainActivity:
private RequestQueue mRequestQueue;
public RequestQueue getRequestQueue() {
if (mRequestQueue == null) {
mRequestQueue = Volley.newRequestQueue(getApplicationContext());
}
return mRequestQueue;
}
public <T> void addToRequestQueue(Request<T> req, String tag) {
req.setTag(TextUtils.isEmpty(tag) ? TAG : tag);
getRequestQueue().add(req);
}
public <T> void addToRequestQueue(Request<T> req) {
req.setTag(TAG);
getRequestQueue().add(req);
}

What's this concept called?

We have this method to make a request using the Volley library:
public void requestWithSomeHttpHeaders() {
RequestQueue queue = Volley.newRequestQueue(this);
String url = "http://www.somewebsite.com";
StringRequest getRequest = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>()
{
#Override
public void onResponse(String response) {
// response
Log.d("Response", response);
}
},
new Response.ErrorListener()
{
#Override
public void onErrorResponse(VolleyError error) {
// TODO Auto-generated method stub
Log.d("ERROR","error => "+error.toString());
}
}
) {
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String, String> params = new HashMap<String, String>();
params.put("User-Agent", "Nintendo Gameboy");
params.put("Accept-Language", "fr");
return params;
}
};
queue.add(getRequest);
}
Notice the part:
{
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String, String> params = new HashMap<String, String>();
params.put("User-Agent", "Nintendo Gameboy");
params.put("Accept-Language", "fr");
return params;
}
};
It confuses me because there's no comma before it, so it's not a function argument. If you look at the method definition:
public StringRequest(
int method,
String url,
Listener<String> listener,
#Nullable ErrorListener errorListener) {
super(method, url, errorListener);
mListener = listener;
}
there's no clear code which explains support for this.
What's this concept called and how do you write code that supports this?

This snippet shows the creation of an instance of an anonymous class that extends StringRequest and overrides the getHeaders() method.

Calling an API with string parametrs in Android with Volley

I'am trying to call an API that adds data to a dynamoDB each time a user creates an account .
The url of the API is in the following format :
https://t3x9lg8utf.execute-api.us-east-2.amazonaws.com/prod? id=""&username=""&numero_passeport=""&decision=""
The problem is that when i call the API using volley i get this error :
06-03 14:32:23.599 13503-14515/com.amazonaws.youruserpools.CognitoYourUserPoolsDemo E/Volley: [14796] BasicNetwork.performRequest: Unexpected response code 400 for https://t3x9lg8utf.execute-api.us-east-2.amazonaws.com/prod
The code i used to call the API :
StringRequest sr = new StringRequest(Request.Method.GET, "https://t3x9lg8utf.execute-api.us-east-2.amazonaws.com/prod",
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
Log.e("HttpClient", "success! response: " + response.toString());
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.e("HttpClient", "error: " + error.toString());
}
})
{
#Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
params.put("id","\"\"");
params.put("username","\"zaeae\"");
params.put("numero_passeport","\"\"");
params.put("decision","\"\"");
return params;
}
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String,String> params = new HashMap<String, String>();
return params;
}
};
queue.add(sr);

try this
StringRequest sr = new StringRequest(Request.Method.GET, "https://t3x9lg8utf.execute-api.us-east-2.amazonaws.com/prod?id="+Uri.encode(id)+"&username="+Uri.encode(username)+"&numero_passeport="+Uri.encode(numero_passeport)+"&decision="+Uri.encode(decision),
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
Log.e("HttpClient", "success! response: " + response.toString());
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.e("HttpClient", "error: " + error.toString());
}
})
{
#Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
params.put("id","\"\"");
params.put("username","\"zaeae\"");
params.put("numero_passeport","\"\"");
params.put("decision","\"\"");
return params;
}
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String,String> params = new HashMap<String, String>();
return params;
}
};
queue.add(sr);
also pass values for id, username, numero_passeport and decision

? id=""&
These are URL parameters, which cannot be passed via getParams()
You need to append them to the string after Request.Method.GET

Volley returns null on first call from method

I am trying to retrieve data from server using volley, but when I call this method the first time, I get the response from server, but null is returned by the method. If I call it the second time I get the last response.
public String retrieveDataFromServer(String url, String param, final String token){
StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try{
data = new JSONObject(response).toString();
}catch (Exception e){}
//Toast.makeText(getApplicationContext(), "wow" + data, Toast.LENGTH_SHORT).show();
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
try{
data = new JSONObject(error.toString()).toString();
}catch (Exception e){}
//Toast.makeText(getApplicationContext(), "" +data, Toast.LENGTH_SHORT).show();
}
}) {
/**
* Passing some request headers
*/
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
String bearer = "Bearer ".concat(token);
Map<String, String> headersSys = super.getHeaders();
HashMap<String, String> headers = new HashMap<String, String>();
headers.put("Content-Type", "application/json; charset=utf-8");
//headers.put("token", token);
headersSys.remove("Authorization");
headers.put("Authorization", bearer);
headers.putAll(headersSys);
return headers;
}
};
// Adding request to request queue
addToRequestQueue(stringRequest);
//Toast.makeText(getApplicationContext(), "wow" + data, Toast.LENGTH_SHORT).show();
return data;
}
How do I get the response on first call of method?

You can use call back to return Volley response:
public void retrieveDataFromServer(final VolleyCallback callback) {
StringRequest strReq = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
callback.onSuccess(response);
}
}
}}
Create interface:
public interface VolleyCallback{
void onSuccess(String response);
}
And get result from activity:
String yourString = "";
#override
public void onResume() {
super.onResume();
retrieveDataFromServer(new VolleyCallback(){
#Override
public void onSuccess(String response){
//Get result from here
yourString = response;
}
});
}

Send a JSONArray POST request with android volley library

I would like to send and receive a Json Array with volley.
Now I can receive an array and it's ok but I don't know how to send a request (For example: with post method).
JsonArrayRequest arrayReq = new JsonArrayRequest(URL,
new Listener<JSONArray>() {
}

List<Map<String,String>> listMap = new ArrayList<Map<String, String>>();
Map<String,String> map = new HashMap<String,String>();
try {
map.put("email", customer.getEmail());
map.put("password",customer.getPassword());
} catch (Exception e) {
e.printStackTrace();
}
listMap.add(map);
String url = PersonalConstants.BASE_URL+"/url";
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(
Request.Method.POST, url, String.valueOf(new JSONArray(listMap)),
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject jsonObject) {
Log.d(App.TAG, jsonObject.toString());
}
}, new Response.ErrorListener (){
#Override
public void onErrorResponse(VolleyError volleyError) {
Log.d(App.TAG,volleyError.toString());
}
}
);
App.getInstance().getmRequestQueue().add(jsonObjectRequest);

Here is an example:
// Define the web service URL
final String URL = "http://www.someurl.com";
// POST params to be sent to the server
HashMap<String, String> params = new HashMap<String, String>();
params.put("name", "raha tamjid");
// Define the POST request
JsonObjectRequest req = new JsonObjectRequest(URL, new JSONObject(params),
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
VolleyLog.v("Response:%n %s", response.toString(4));
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
VolleyLog.e("Error: ", error.getMessage());
}
});
// Add the request object to the queue to be executed
ApplicationController.getInstance().addToRequestQueue(req);
How the POST request differs is that it takes a JSONObject as parameter.
EDIT 1:
If you have Volley installed as a library project in your IDE, then just define a new constructor
public JsonArrayRequest(int method, String url, JSONObject jsonRequest,
Listener<JSONArray> listener, ErrorListener errorListener) {
super(method, url, (jsonRequest == null) ? null : jsonRequest.toString(), listener, errorListener);
}
inside the class JsonArrayRequest which is present in the Volley library code. Now you can use this to create JsonArrayRequest objects and add them to the RequestQueue.
EDIT 2:
1. Get the Volley library project from here. Download the project and set it up in your IDE.
2. Make the modification to the JsonRequest class (found in com.android.volley.toolbox namespace) as discussed in EDIT 1.
3. Delete the volley.jar from the libs folder of your APPLICATION PROJECT.
4. Now go to Project Properties -> Android -> Library and click on Add. From here select the Volley project. Clean & Rebuild.
5. Now in your APPLICATION PROJECT you can make a POST JsonArrayRequest just like how we make a POST JsonObjectRequest and get a JSONArray in the Response.

Create a class and extend JsonArrayRequest then override
#Override
protected Map<String, String> getParams() throws AuthFailureError {
HashMap<String, String> params = new HashMap<String, String>();
params.put("name", "value");
return params;
}
and add a new constructor and in it call
super(Method.POST, url, null, listener, errorListener);
or use this class
public class PostJsonArrayRequest extends JsonRequest<JSONArray> {
/**
* Creates a new request.
* #param url URL to fetch the JSON from
* #param listener Listener to receive the JSON response
* #param errorListener Error listener, or null to ignore errors.
*/
public PostJsonArrayRequest(String url, Response.Listener<JSONArray> listener, Response.ErrorListener errorListener) {
super(Method.POST, url, null, listener, errorListener);
}
#Override
protected Map<String, String> getParams() throws AuthFailureError {
HashMap<String, String> params = new HashMap<String, String>();
params.put("name", "value");
return params;
}
#Override
protected Response<JSONArray> parseNetworkResponse(NetworkResponse response) {
try {
String jsonString =
new String(response.data, HttpHeaderParser.parseCharset(response.headers));
return Response.success(new JSONArray(jsonString),
HttpHeaderParser.parseCacheHeaders(response));
} catch (UnsupportedEncodingException e) {
return Response.error(new ParseError(e));
} catch (JSONException je) {
return Response.error(new ParseError(je));
}
}
}

Create a new java class named JsonArrayPostRequest now you can use it like the previous request, just replace JSONArrayRequest with JsonArrayPostRequest and pass the correct parameters
public class JsonArrayPostRequest extends Request<JSONArray>{
private Map<String,String> mParam;
private Listener<JSONArray> mListener;
public JsonArrayPostRequest(String url,Listener<JSONArray> listener, ErrorListener errorListener,Map param) {
super(Request.Method.POST, url, errorListener);
mListener=listener;
mParam=param;
}
#Override
protected Map<String, String> getParams() throws AuthFailureError {
return mParam;
}
#Override
protected Response<JSONArray> parseNetworkResponse(NetworkResponse response) {
try {
String jsonString =
new String(response.data, HttpHeaderParser.parseCharset(response.headers));
return Response.success(new JSONArray(jsonString),
HttpHeaderParser.parseCacheHeaders(response));
} catch (UnsupportedEncodingException e) {
return Response.error(new ParseError(e));
} catch (JSONException je) {
return Response.error(new ParseError(je));
}
}
#Override
protected void deliverResponse(JSONArray response) {
mListener.onResponse(response);
}
}
USE:
JsonArrayPostRequest request = new JsonArrayPostRequest(URL,new Response.Listener<JSONArray>(),
new Response.ErrorListener() ,params);