Send POST request with JSON data using Volley

Question

I would like to send a new JsonObjectRequest request:

• I want to receive JSON data (response from server): OK

• I want to send JSON form

Answer 1

I know that this thread is quite old, but I had this problem and I came up with a cool solution which can be very useful to many because it corrects/extended the Volley library on many aspects.

I spotted some not supported-out-of-box Volley features:

• This JSONObjectRequest is not perfect: you have to expect a JSON at the end (see the Response.Listener<JSONObject>).
• What about Empty Responses (just with a 200 status)?
• What do I do if I want directly my POJO from the ResponseListener?

I more or less compiled a lot of solutions in a big generic class in order to have a solution for all the problem I quoted.

  /**
  * Created by laurentmeyer on 25/07/15.
  */
 public class GenericRequest<T> extends JsonRequest<T> {

     private final Gson gson = new Gson();
     private final Class<T> clazz;
     private final Map<String, String> headers;
     // Used for request which do not return anything from the server
     private boolean muteRequest = false;

     /**
      * Basically, this is the constructor which is called by the others.
      * It allows you to send an object of type A to the server and expect a JSON representing a object of type B.
      * The problem with the #JsonObjectRequest is that you expect a JSON at the end.
      * We can do better than that, we can directly receive our POJO.
      * That's what this class does.
      *
      * @param method:        HTTP Method
      * @param classtype:     Classtype to parse the JSON coming from the server
      * @param url:           url to be called
      * @param requestBody:   The body being sent
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      * @param headers:       Added headers
      */
     private GenericRequest(int method, Class<T> classtype, String url, String requestBody,
                           Response.Listener<T> listener, Response.ErrorListener errorListener, Map<String, String> headers) {
         super(method, url, requestBody, listener,
                 errorListener);
         clazz = classtype;
         this.headers = headers;
         configureRequest();
     }

     /**
      * Method to be called if you want to send some objects to your server via body in JSON of the request (with headers and not muted)
      *
      * @param method:        HTTP Method
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param toBeSent:      Object which will be transformed in JSON via Gson and sent to the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      * @param headers:       Added headers
      */
     public GenericRequest(int method, String url, Class<T> classtype, Object toBeSent,
                           Response.Listener<T> listener, Response.ErrorListener errorListener, Map<String, String> headers) {
         this(method, classtype, url, new Gson().toJson(toBeSent), listener,
                 errorListener, headers);
     }

     /**
      * Method to be called if you want to send some objects to your server via body in JSON of the request (without header and not muted)
      *
      * @param method:        HTTP Method
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param toBeSent:      Object which will be transformed in JSON via Gson and sent to the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      */
     public GenericRequest(int method, String url, Class<T> classtype, Object toBeSent,
                           Response.Listener<T> listener, Response.ErrorListener errorListener) {
         this(method, classtype, url, new Gson().toJson(toBeSent), listener,
                 errorListener, new HashMap<String, String>());
     }

     /**
      * Method to be called if you want to send something to the server but not with a JSON, just with a defined String (without header and not muted)
      *
      * @param method:        HTTP Method
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param requestBody:   String to be sent to the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      */
     public GenericRequest(int method, String url, Class<T> classtype, String requestBody,
                           Response.Listener<T> listener, Response.ErrorListener errorListener) {
         this(method, classtype, url, requestBody, listener,
                 errorListener, new HashMap<String, String>());
     }

     /**
      * Method to be called if you want to GET something from the server and receive the POJO directly after the call (no JSON). (Without header)
      *
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      */
     public GenericRequest(String url, Class<T> classtype, Response.Listener<T> listener, Response.ErrorListener errorListener) {
         this(Request.Method.GET, url, classtype, "", listener, errorListener);
     }

     /**
      * Method to be called if you want to GET something from the server and receive the POJO directly after the call (no JSON). (With headers)
      *
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      * @param headers:       Added headers
      */
     public GenericRequest(String url, Class<T> classtype, Response.Listener<T> listener, Response.ErrorListener errorListener, Map<String, String> headers) {
         this(Request.Method.GET, classtype, url, "", listener, errorListener, headers);
     }

     /**
      * Method to be called if you want to send some objects to your server via body in JSON of the request (with headers and muted)
      *
      * @param method:        HTTP Method
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param toBeSent:      Object which will be transformed in JSON via Gson and sent to the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      * @param headers:       Added headers
      * @param mute:          Muted (put it to true, to make sense)
      */
     public GenericRequest(int method, String url, Class<T> classtype, Object toBeSent,
                           Response.Listener<T> listener, Response.ErrorListener errorListener, Map<String, String> headers, boolean mute) {
         this(method, classtype, url, new Gson().toJson(toBeSent), listener,
                 errorListener, headers);
         this.muteRequest = mute;
     }

     /**
      * Method to be called if you want to send some objects to your server via body in JSON of the request (without header and muted)
      *
      * @param method:        HTTP Method
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param toBeSent:      Object which will be transformed in JSON via Gson and sent to the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      * @param mute:          Muted (put it to true, to make sense)
      */
     public GenericRequest(int method, String url, Class<T> classtype, Object toBeSent,
                           Response.Listener<T> listener, Response.ErrorListener errorListener, boolean mute) {
         this(method, classtype, url, new Gson().toJson(toBeSent), listener,
                 errorListener, new HashMap<String, String>());
         this.muteRequest = mute;

     }

     /**
      * Method to be called if you want to send something to the server but not with a JSON, just with a defined String (without header and not muted)
      *
      * @param method:        HTTP Method
      * @param url:           URL to be called
      * @param classtype:     Classtype to parse the JSON returned from the server
      * @param requestBody:   String to be sent to the server
      * @param listener:      Listener of the request
      * @param errorListener: Error handler of the request
      * @param mute:          Muted (put it to true, to make sense)
      */
     public GenericRequest(int method, String url, Class<T> classtype, String requestBody,
                           Response.Listener<T> listener, Response.ErrorListener errorListener, boolean mute) {
         this(method, classtype, url, requestBody, listener,
                 errorListener, new HashMap<String, String>());
         this.muteRequest = mute;

     }


     @Override
     protected Response<T> parseNetworkResponse(NetworkResponse response) {
         // The magic of the mute request happens here
         if (muteRequest) {
             if (response.statusCode >= 200 && response.statusCode <= 299) {
                 // If the status is correct, we return a success but with a null object, because the server didn't return anything
                 return Response.success(null, HttpHeaderParser.parseCacheHeaders(response));
             }
         } else {
             try {
                 // If it's not muted; we just need to create our POJO from the returned JSON and handle correctly the errors
                 String json = new String(response.data, HttpHeaderParser.parseCharset(response.headers));
                 T parsedObject = gson.fromJson(json, clazz);
                 return Response.success(parsedObject, HttpHeaderParser.parseCacheHeaders(response));
             } catch (UnsupportedEncodingException e) {
                 return Response.error(new ParseError(e));
             } catch (JsonSyntaxException e) {
                 return Response.error(new ParseError(e));
             }
         }
         return null;
     }

     @Override
     public Map<String, String> getHeaders() throws AuthFailureError {
         return headers != null ? headers : super.getHeaders();
     }

     private void configureRequest() {
         // Set retry policy
         // Add headers, for auth for example
         // ...
     }
 }

It could seem a bit overkill but it's pretty cool to have all these constructors because you have all the cases:

(The main constructor wasn't meant to be used directly although it's, of course, possible).

1. Request with response parsed to POJO / Headers manually set / POJO to Send
2. Request with response parsed to POJO / POJO to Send
3. Request with response parsed to POJO / String to Send
4. Request with response parsed to POJO (GET)
5. Request with response parsed to POJO (GET) / Headers manually set
6. Request with no response (200 - Empty Body) / Headers manually set / POJO to Send
7. Request with no response (200 - Empty Body) / POJO to Send
8. Request with no response (200 - Empty Body) / String to Send

Of course, in order that it works, you have to have Google's GSON Lib; just add:

compile 'com.google.code.gson:gson:x.y.z'

to your dependencies (current version is 2.3.1).

Answer 2

    final String url = "some/url";

instead of:

    final JSONObject jsonBody = "{\"type\":\"example\"}";

you can use:

  JSONObject jsonBody = new JSONObject();
    try {
        jsonBody.put("type", "my type");
    } catch (JSONException e) {
        e.printStackTrace();
    }
new JsonObjectRequest(url, jsonBody, new Response.Listener<JSONObject>() { ... });

Answer 3

You can also send data by overriding getBody() method of JsonObjectRequest class. As shown below.

    @Override
    public byte[] getBody()
    {

        JSONObject jsonObject = new JSONObject();
        String body = null;
        try
        {
            jsonObject.put("username", "user123");
            jsonObject.put("password", "Pass123");

            body = jsonObject.toString();
        } catch (JSONException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        try
        {
            return body.toString().getBytes("utf-8");
        } catch (UnsupportedEncodingException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return null;
    }

Answer 4

JsonObjectRequest actually accepts JSONObject as body.

From this blog article,

final String url = "some/url";
final JSONObject jsonBody = new JSONObject("{\"type\":\"example\"}");

new JsonObjectRequest(url, jsonBody, new Response.Listener<JSONObject>() { ... });

Here is the source code and JavaDoc (@param jsonRequest):

/**
 * Creates a new request.
 * @param method the HTTP method to use
 * @param url URL to fetch the JSON from
 * @param jsonRequest A {@link JSONObject} to post with the request. Null is allowed and
 *   indicates no parameters will be posted along with request.
 * @param listener Listener to receive the JSON response
 * @param errorListener Error listener, or null to ignore errors.
 */
public JsonObjectRequest(int method, String url, JSONObject jsonRequest,
        Listener<JSONObject> listener, ErrorListener errorListener) {
    super(method, url, (jsonRequest == null) ? null : jsonRequest.toString(), listener,
                errorListener);
}

Answer 5

• Create an object of RequestQueue class.

  RequestQueue queue = Volley.newRequestQueue(this);
  

• Create a StringRequest with response and error listener.

   StringRequest sr = new StringRequest(Request.Method.POST,"http://api.someservice.com/post/comment", new Response.Listener<String>() {
      @Override
      public void onResponse(String response) {
          mPostCommentResponse.requestCompleted();
      }
  }, new Response.ErrorListener() {
      @Override
      public void onErrorResponse(VolleyError error) {
          mPostCommentResponse.requestEndedWithError(error);
      }
  }){
      @Override
      protected Map<String,String> getParams(){
          Map<String,String> params = new HashMap<String, String>();
          params.put("user",userAccount.getUsername());
          params.put("pass",userAccount.getPassword());
          params.put("comment", Uri.encode(comment));
          params.put("comment_post_ID",String.valueOf(postId));
          params.put("blogId",String.valueOf(blogId));
  
          return params;
      }
  
      @Override
      public Map<String, String> getHeaders() throws AuthFailureError {
          Map<String,String> params = new HashMap<String, String>();
          params.put("Content-Type","application/x-www-form-urlencoded");
          return params;
      }
  };
  

• Add your request into the RequestQueue.

  queue.add(jsObjRequest);
  

• Create PostCommentResponseListener interface just so you can see it. It’s a simple delegate for the async request.

  public interface PostCommentResponseListener {
  public void requestStarted();
  public void requestCompleted();
  public void requestEndedWithError(VolleyError error);
  }
  

• Include INTERNET permission inside AndroidManifest.xml file.

  <uses-permission android:name="android.permission.INTERNET"/>
  

Answer 6

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

   JSONObject JObj = new JSONObject();

   try {
           JObj.put("Id","1");
           JObj.put("Name", "abc");

   } catch (Exception e) {
       e.printStackTrace();
   }

   params.put("params", JObj.toString());
   // Map.Entry<String,String>
   Log.d("Parameter", params.toString());
   return params;
}