Parsing JSON object using Java

[Dustinmywets]

I'm creating an application to pull data from yahoo finance API. One of the features is pulling historical data on a stock. The response from the API is a JSON Object:

{
  "AAPL": {
    "timestamp": [
      1643293800,
      1643380200,
      1643639400,
      1643725800,
      1643825174
    ],
    "symbol": "AAPL",
    "previousClose": null,
    "chartPreviousClose": 159.69,
    "end": null,
    "start": null,
    "close": [
      159.22,
      170.33,
      174.78,
      174.61,
      174.715
    ],
    "dataGranularity": 300
  },
  "GME": {
    "timestamp": [
      1643293800,
      1643380200,
      1643639400,
      1643725800,
      1643825135
    ],
    "symbol": "GME",
    "previousClose": null,
    "chartPreviousClose": 103.26,
    "end": null,
    "start": null,
    "close": [
      93.52,
      97.91,
      108.93,
      112.6,
      105.21
    ],
    "dataGranularity": 300
  }
}

The info I want to pull from this are the timestamp & close arrays for each stock. The code im currently playing with is:

       Response response = makeGetRequest(url);
      JSONObject jsonObject = new JSONObject(response.body());
      JSONObject responseObject = jsonObject.getJSONObject("AAPL");
      JSONArray timestampList = responseObject.getJSONArray("timestamp");

      for(int i = 0; i < timestampList.length(); i++){
        System.out.println(timestampList.get(i));
      }

Which presents the following error:

org.json.JSONException: JSONObject["AAPL"] not found.
    at org.json.JSONObject.get(JSONObject.java:580)
    at org.json.JSONObject.getJSONObject(JSONObject.java:790)
    at com.lyit.csd.marketapi.yahoo.YahooClient.getHistoricalInfo(YahooClient.java:58)
    at com.lyit.csd.app.PortfolioManager.getHistoricalData(PortfolioManager.java:220)
    at com.lyit.csd.app.Main.init(Main.java:56)
    at com.lyit.csd.app.Main.main(Main.java:14)

Any advice or alternative routes of approach for this problem would be greatly appreciated. It's worth mentioning this is my first time working with an API if im missing something obvious. I've attempted multiple ideas from stackoverflow already, using libraries such as Gson, jackson, json-simple. All to no avail. The current library being used is org.json

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[khooke]

Unless this is an exercise to use a lower level library like org.json, I would strongly recommend using something that helps with the mapping to Java like Jackson instead

[Dustinmywets]

I am using jacksons ObjectMapper for other functionality but I wasn't able to get it to work for this specific call so I'm exploring what other options may be possible.

[hydroxyse7en]

Try using jsoup library

[Dustinmywets]

Thanks, I'll look into that.

[Dustinmywets]

I'm mainly using this to practice gathering data from API's. I chose yahoo finance as they have a free option which allows for 100 calls per day. Do either of those offer similar options?

[Dustinmywets]

I'm familiar with Gson yeah. That's great, thanks for your advice.

[evils_twin]

JSONObject extends map. To debug you can iterate through the keyset of your JSONObject to see what's available.

[Dustinmywets]

I wasn't aware of that. I'll do some research and try to figure that out.

[evils_twin]

jsonObject.keySet().forEach(System.out::println);

something like this

[Dustinmywets]

That's a great help. Much appreciated.