How to send request Header is "Content-Type":"application/json" when GET on Volley

Question

I try to use GET on Volley , but i need send request to application/json .

I take a look for some answers , i try to use jsonBody , but it shows error:

null com.android.volley.ServerError

Here is my code:

public class MainActivity extends AppCompatActivity {

    String url = "http://114.35.246.42:2212/MobileApp/DEST_WebService.asmx/GetNews";
    JSONObject jsonBody;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        try {
            //I try to use this for send Header is application/json
            jsonBody = new JSONObject("{\"type\":\"example\"}");
        } catch (JSONException ex) {
            ex.printStackTrace();
        }

        RequestQueue mQueue = Volley.newRequestQueue(getApplicationContext());

        JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(url, jsonBody,
                new Response.Listener<JSONObject>() {


                    @Override
                    public void onResponse(JSONObject response) {
                        Log.d("TAG", response.toString());
                    }
                }, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {
                Log.e("TAG", error.getMessage(), error);
            }


        });


        mQueue.add(jsonObjectRequest);

    }


}

Is any one can teach me how to fix this , any help would be appreciated.

Here is my url: String url = "http://114.35.246.42:2212/MobileApp/DEST_WebService.asmx/GetNews";

`jsonBody` is the **body**, not a header. You are getting a ServerError, so there is a log message somewhere that you should read instead of the logcat — OneCricketeer, Apr 19 '17 at 04:09

score 17 · Accepted Answer · edited Mar 21 '18 at 10:59

17

@Override 
public Map<String, String> getHeaders() throws AuthFailureError { 
    Map<String, String> params = new HashMap<String, String>();                
    params.put("Content-Type", "application/json");
    return params; 
}

Implementation in your's

public class MainActivity extends AppCompatActivity {

    String url = "http://114.35.246.42:2212/MobileApp/DEST_WebService.asmx/GetNews";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        RequestQueue mQueue = Volley.newRequestQueue(getApplicationContext());

        JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(url, jsonBody,
            new Response.Listener<JSONObject>() {
                @Override
                public void onResponse(JSONObject response) {
                    Log.d("TAG", response.toString());
                }
            }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    Log.e("TAG", error.getMessage(), error);
                }
            }) { //no semicolon or coma
            @Override 
            public Map<String, String> getHeaders() throws AuthFailureError { 
                Map<String, String> params = new HashMap<String, String>();                
                params.put("Content-Type", "application/json");
                return params; 
            } 
        };
        mQueue.add(jsonObjectRequest);
    }
}

edited Mar 21 '18 at 10:59

Komal12

3,340
4
16
25

answered Apr 19 '17 at 04:06

Mukeshkumar S

785
1
14
30

Thanks for your responding , where should i put this code ? – Morton Apr 19 '17 at 04:29
i got it , thanks for your answer , but it show the result not like post man – Morton Apr 19 '17 at 04:41
@徐博俊 Your Response is XML Not JSON. – Mukeshkumar S Apr 19 '17 at 05:27
@徐博俊 Please Check the Image and Let me know – Mukeshkumar S Apr 19 '17 at 05:44
I check the web site , the image has been delete – Morton Apr 19 '17 at 05:56
Hey , i see your answer again and correct the code, i can get the json data now , but how do you post json and get without `d` – Morton Apr 19 '17 at 06:02
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/142039/discussion-between-maharith-aditya-s-s-and-). – Mukeshkumar S Apr 19 '17 at 06:05
@NarendraJi Please Refer this link - https://stackoverflow.com/questions/25994514/volley-timeout-error – Mukeshkumar S Feb 28 '18 at 09:47
Some backend frameworks expect a "Accept:application/json" header in their API endpoints. This was my case. After half an hour, adding that header to the code you provided made the trick . – Rodrigo Chiong Apr 28 '18 at 10:34

score 5 · Answer 2 · answered Apr 19 '17 at 04:04

5

In general for setting a custom header you need to override getHeaders and set the custom header manually. However, volley handles content type headers differently and getHeaders way does not always work.

So for your case you need to override getBodyContentType. So your code will look like

JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(url, jsonBody,new Response.Listener<JSONObject>() {

@Override
public void onResponse(JSONObject response) {
   Log.d("TAG", response.toString());
}, new Response.ErrorListener(){
        @Override
        public void onErrorResponse(VolleyError error) {
            Log.e("TAG", error.getMessage(), error);
        }


    }){
         @Override
         public String getBodyContentType(){
              return "application/json";
         }
    };

answered Apr 19 '17 at 04:04

ashkhn

1,642
1
13
18

Yeah I know. But seems it doesn't work for OP that's why I posted the manual way of doing it – ashkhn Apr 19 '17 at 04:10
Thanks for your responding man , i try to use `@Override public String getBodyContentType(){ return "application/json"; }` , it shows 'org.json.JSONException: Value – Morton Apr 19 '17 at 04:19
The body comes back as XML without the header. The server processes the header, so maybe the server's you've used don't read that correctly @akash93 – OneCricketeer Apr 19 '17 at 04:25
So i try to use application/json , let the data `{ "d": "{\"Msg\":\"Successful [0000]"....`handle easily – Morton Apr 19 '17 at 04:28

OneCricketeer · Answer 3 · 2017-04-19T04:28:34.333

4

I try to use GET on Volley

The docs for the method you are calling says this

Constructor which defaults to GET if jsonRequest is null, POST otherwise

You can't GET with an HTTP JSON body. Maybe that's the error.

//I try to use this for send Header is application/json
jsonBody = new JSONObject("{\"type\":\"example\"}");

That's not the header, so pass in null here to do GET

new JsonObjectRequest(url, null,

And towards the end of your request, override a method to request JSON

        ... 

        @Override
        public void onErrorResponse(VolleyError error) {
            Log.e("TAG", error.getMessage(), error);
        }


    }) { // Notice no semi-colon here
        @Override 
        public Map<String, String> getHeaders() throws AuthFailureError { 
            Map<String, String> params = new HashMap<String, String>();                
            params.put("Content-Type", "application/json");
            return params; 
        } 
    };

edited Apr 19 '17 at 04:28

answered Apr 19 '17 at 04:12

OneCricketeer

179,855
19
132
245

My data is not correct that is ` {"Msg":"Successful [0000]"....` , but if i use post man send GET by application/json , it will get `{ "d": "{\"Msg\":\"Successful [0000]"....` , So i ask this question. – Morton Apr 19 '17 at 04:16
Alright, maybe you will need to override `getHeaders()`, then – OneCricketeer Apr 19 '17 at 04:21
It' fine , thanks your answer about `new JsonObjectRequest(url, null,` – Morton Apr 19 '17 at 04:26
Seems like the real issue is that the json you receive is invalid since it contains the xml tag. Once you fix that your code should work fine without needing to override any methods since the content type header is set automatically by JsonRequest as @cricket_007 mentioned earler – ashkhn Apr 19 '17 at 04:44
@akash93 I tried the request myself. It returns JSON when the header is added – OneCricketeer Apr 19 '17 at 13:15

score 1 · Answer 4 · edited Apr 19 '17 at 04:06

Use String request instead of jsonrequest like this

            StringRequest loginMe = new StringRequest(Request.Method.GET, "http://114.35.246.42:2212/MobileApp/DEST_WebService.asmx/GetNews", new Response.Listener<String>() {

                @Override
                public void onResponse(String response) {

                    System.out.println("LoginActivity -- onResponse --> " + response);

                    if (progressDialog != null) {

                        progressDialog.dismiss();

                    }

                    try {

                        JSONObject jsonObject = new JSONObject(response);

                    } catch (Exception e) {

                        CommonUtility.somethingWentWrongDialog(activity,
                                "LoginActivity -- onResponse-- Exception --> ".concat(e.getMessage()));

                    }
                }
            }, new Response.ErrorListener() {

                @Override
                public void onErrorResponse(VolleyError error) {

                    if (progressDialog != null) {

                        progressDialog.dismiss();

                    }

                    CommonUtility.somethingWentWrongDialog(activity,
                            "LoginActivity -- onErrorResponse --> ".concat(error.getMessage()));

                }
            }) {

                @Override
                protected Map<String, String> getParams() {

                    Map<String, String> params = new HashMap<>();


                    System.out.println("LoginActivity -- LoginParams --> " + params.toString());

                    return params;

                }
            };

            loginMe.setRetryPolicy(new DefaultRetryPolicy(60000, DefaultRetryPolicy.DEFAULT_MAX_RETRIES,
                    DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));

            Volley.newRequestQueue(activity).add(loginMe);

Please **do not copy paste** sample code. Edit it to suit the question requirements. The above code contains random lines which have nothing to do with the question. — ashkhn, Apr 19 '17 at 04:06

How to send request Header is "Content-Type":"application/json" when GET on Volley

4 Answers4

Linked

Related