Send rerquest to server (with optional json data to post), and Listen for ServerResponse using Interface. Uses okhttp3 (Android)

NetworkCall.java

import android.os.AsyncTask;
import android.util.Log;

import org.json.JSONException;

import java.io.IOException;

import okhttp3.MediaType;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;

/**
 * Created by ASWIN on 5/3/2017.
 */

public class NetworkCall extends AsyncTask<String, String, String> {

    String TAG="NETWORK_CALL";
    ServerResponseListner mListener;
    String type,URL,REQ_JSON;

    public NetworkCall(String type) {
        this.type = type;
    }

    public void setListener(ServerResponseListner listener){
        mListener = listener;
    }

    protected void onPreExecute() {
        super.onPreExecute();

    }

    @Override
    protected String doInBackground(String... params) {

        String json = params[0];
        String url=params[1];
        this.URL=url;
        this.REQ_JSON=json;
        String jsonResponse=null;

        final MediaType JSON = MediaType.parse("application/json; charset=utf-8");

        OkHttpClient client = new OkHttpClient();

            RequestBody body = RequestBody.create(JSON, json);
            Request request = new Request.Builder()
                    .url(url)
                    .post(body)
                    .build();
        Response response = null;
        try {
            response = client.newCall(request).execute();
            jsonResponse= response.body().string();
        } catch (IOException e) {
            e.printStackTrace();
            mListener.onNetworkException(e);
        }
        return  jsonResponse;
    }


    @Override
    protected void onPostExecute(String s) {
        try {
            s = s.trim();
            Log.d(TAG, "\n\t*****************************************" +
                    "\n\t REQUEST TYPE : "+ type
                    +"\n\t URL : "+URL
                    +"\n\t REQUEST DATA : "+REQ_JSON
                    +"\n\t SERVER RESPONSE : "+s+"\n" +
                    "\t*************************************************" +
                    "\n " );
            String[] response=new String[]{type,s};
            try {
                mListener.onResponse(response);
            } catch (JSONException e) {
                e.printStackTrace();
            }
        }catch (Exception e){
            e.printStackTrace();
        }

    }
}

ServerResponseListner.java

import org.json.JSONException;

/**
 * Created by ASWIN on 5/6/2017.
 */

public interface ServerResponseListner {
    void onResponse(String[] response) throws JSONException;
    void onNetworkException(Exception e);
}

UsageExample.java

/**
 * Created by ASWIN on 5/6/2017.
 */

public class UsageExample extends AppCompatActivity implements ServerResponseListner{
  
  private static final String TAG="RECIEVING_DATA";
  private static final String MY_NETWORK_CALL_1="myFirstNetworkCall";
  private static final String MY_NETWORK_CALL_2="mySecondNetworkCall";

  @Override
  protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_edit_student);
  
    
    //*************************FIRST NETWORK CALL******************************** 
    NetworkCall networkCall=new NetworkCall(MY_NETWORK_CALL_1);
        networkCall.setListener(UsageExample.this);
        networkCall.execute(CreatePOST_JSON,"https://posttestserver.com/post.php");
   //**************************************************************************** 
    
    
    
    //*************************SECOND NETWORK CALL******************************** 
    NetworkCall networkCall2=new NetworkCall(MY_NETWORK_CALL_2);
        networkCall2.setListener(UsageExample.this);
        //networkcall without any json data to post
        networkCall2.execute("","https://posttestserver.com/post.php");    
    //****************************************************************************
    }
  
   @Override
    public void onResponse(String[] response) throws JSONException {
        
      if(response[0].equals(MY_NETWORK_CALL_1)){
          //This is the response of the first NetworkCall
            Log.d(TAG,response[1]);
        }else
          if(response[0].equals(MY_NETWORK_CALL_2)){
          //This is the response of the second NetworkCall
            Log.d(TAG,response[1]);
          }
    }

    @Override
    public void onNetworkException(Exception e) {
        Snackbar snackbar=Snackbar.make(layout,"Please check your Internet connection",Snackbar.LENGTH_LONG);
        snackbar.show();
    }
  
   private String CreatePOST_JSON() throws JSONException {
        JSONObject object=new JSONObject();
        object.put("POST_DATA","This is the data to be sent to the server");
        return  object.toString();
    }

}