convert foursquare http response to JSON for java

Question

Having received the following response from Foursquare, when I try to parse it, I get the error below:

Response:

{"meta":{"code":200},"response":{"venues":[{"id":"4b1c3ce9f964a520d60424e3","name":"Folsom Lake Bowl","contact":{},"location":{"address":"511 East Bidwell","lat":38.67291745,"lng":-121.165447,"distance":39,"postalCode":"95630","city":"Folsom","state":"CA"},"categories":[{"id":"4bf58dd8d48988d1e4931735","name":"Bowling Alley","pluralName":"Bowling Alleys","shortName":"Bowling Alley","icon":{"prefix":"https://foursquare.com/img/categories/arts_entertainment/bowling_","sizes":[32,44,64,88,256],"name":".png"},"primary":true}],"verified":false,"stats":{"checkinsCount":592,"usersCount":284,"tipCount":2},"hereNow":{"count":0}}]}}

Error:

Exception in thread "main" org.codehaus.jettison.json.JSONException: JSONObject["groups"] not found.
at org.codehaus.jettison.json.JSONObject.get(JSONObject.java:360)
at org.codehaus.jettison.json.JSONObject.getJSONArray(JSONObject.java:436)
at playaround.FoursquareAPI.get(FoursquareAPI.java:56)
at playaround.FoursquareAPI.main(FoursquareAPI.java:31)

Code:

StringBuilder sb = new StringBuilder();
        BufferedReader reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
        for (String line; null != (line = reader.readLine());) {
            sb.append(line);
        }
        String output = sb.toString();
        JSONObject json = new JSONObject(output);
        JSONArray venues = json.getJSONObject("response").getJSONArray("groups").getJSONObject(0).getJSONArray("items");
        System.out.println(venues.length());

All I want is to read the response from Foursquare as JSONObject in Java. Any help?

Answer 1

Reading that stack trace, the JSON is being parsed just fine.

The problem is that you are trying to read a property that doesn't exist -- "groups"

Answer 2

From my experience, if you get the JSON object - such as the problem I had ;parsing a returned LOCATION field. I started with the following code:

JSONObject jsonObjLoc = new JSONObject(myLocation);

If you can get the Object, then simply refer to "has" parameter like:

if(jsonObjLoc.has("myAddress")) { // name of field to look for 

           myTextAddress = jsonObjLoc.getString("address");
}

I use has to protect against the empty or null field not being returned.