[Solved] Converting JSONObject to JSONArray

I’m currently learning some android programming with JAVA. My teacher shared this piece of code which will consume an API, get its JSON file, and convert it to a JSONArray file. Then he will Iterate through that JSONArray and put them into an ArrayList before displaying them onto an activity.

The problem is that the API that I’m consuming returns a JSONObject file instead, and I do not know how to properly convert this to JSONArray.

import android.util.Log;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;

public class JSONParser {

String charset = "UTF-8";
HttpURLConnection conn;
DataOutputStream wr;
StringBuilder result;
URL urlObj;
JSONArray jObj = null;
StringBuilder sbParams;
String paramsString;

public JSONArray makeHttpRequest(String url, String method) {

    sbParams = new StringBuilder();

   if(method.equals("GET")){
        // request method is GET

        if (sbParams.length() != 0) {
            url += "?" + sbParams.toString();
        }

        try {
            urlObj = new URL(url);

            conn = (HttpURLConnection) urlObj.openConnection();

            conn.setDoOutput(false);

            conn.setRequestMethod("GET");


            conn.setRequestProperty("AccountKey", "pVU56+0hI26DNLeTzlU/Dw==");
            conn.setRequestProperty("UniqueUserId", "33c07f2f-b4c0-4151-acd3-e0829b303d2c");
            conn.setRequestProperty("accept", "application/json");

            conn.setConnectTimeout(15000);

            conn.connect();

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

    }

    try {
        //Receive the response from the server
        InputStream in = new BufferedInputStream(conn.getInputStream());
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));
        result = new StringBuilder();
        String line;
        while ((line = reader.readLine()) != null) {
            result.append(line);
        }

        Log.d("JSON Parser", "result: " + result.toString());

    } catch (IOException e) {
        // e.printStackTrace();
    }

    conn.disconnect();

    // try parse the string to a JSON object
    try {

        jObj = new JSONArray(result.toString());
    } catch (JSONException e) {
        Log.e("JSON Parser", "Error parsing data " + e.toString());
    }

    // return JSON Object
    return jObj;
}

}

API URL and its custom headers:

URL: http://datamall2.mytransport.sg/ltaodataservice/TaxiAvailability

headers-

AccountKey: pVU56+0hI26DNLeTzlU/Dw==
UniqueUserId: 33c07f2f-b4c0-4151-acd3-e0829b303d2c
accept: application/json

EDIT2: I use this to get my raw data with custom headers.
http://requestmaker.com/

EDIT: This is the JSON that I get.

{
  "odata.metadata": "http://datamall2.mytransport.sg/ltaodataservice/$metadata#TaxiAvailability",
  "value": [
    {
      "Longitude": 103.84009,
      "Latitude": 1.35989
    },
    {
      "Longitude": 103.84679,
      "Latitude": 1.35544
    },
    {
      "Longitude": 103.76928,
      "Latitude": 1.4419
    }
    ....
    ]
    }
Enquirer: Kei

||

Solution #1:

Add this in place of jObj = new JSONArray(result.toString());

JSONObject obj = new JSONObject(result.toString());
JSONArray arr = obj.getJSONArray("value");

Now you can use JSONArray arr the way you want.

Respondent: Kei

Solution #2:

JSONObject Jobj = new JSONObject(result.toString());
JSONArray Jarray = obj.getJSONArray("value");

What you need is Jarray.

And then iterate Jarray to get the objects and values Longitude,Latitude in the objects.

Respondent: Rohit5k2

The answers/resolutions are collected from stackoverflow, are licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0 .

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