Getting JSONObject from JSONArray [duplicate]

This question already has answers here: 开发者_JS百科 Accessing members of items in a JSONArray with Java (6 answers) Closed 6 years ago.

I am in a bit of a fix regarding the JSONObject that I am getting as a response from the server.

jsonObj = new JSONObject(resultString);
            JSONObject sync_reponse = jsonObj.getJSONObject("syncresponse");
            String synckey_string = sync_reponse.getString("synckey");
            JSONArray createdtrs_array = sync_reponse.getJSONArray("createdtrs");
            JSONArray modtrs_array = sync_reponse.getJSONArray("modtrs");
            JSONArray deletedtrs_array = sync_reponse.getJSONArray("deletedtrs");
            String deleted_string = deletedtrs_array.toString();

{"syncresponse":{"synckey":"2011-09-30 14:52:00","createdtrs":[],"modtrs":[],"deletedtrs":[{"companyid":"UTB17","username":"DA","date":"2011-09-26","reportid":"31341"}]

as you can see in the response that I am getting I am parsing the JSONObject and creating syncresponse, synckey as a JSON object createdtrs, modtrs, deletedtrs as a JSONArray. I want to access the JSONObject from deletedtrs, so that I can split them apart and use the values. i.e I want to extract companyid, username, date etc.

How can I go about this ?

Thanks for your input.

---

JSONArray objects have a function getJSONObject(int index), you can loop through all of the JSONObjects by writing a simple for-loop:

JSONArray array;
for(int n = 0; n < array.length(); n++)
{
    JSONObject object = array.getJSONObject(n);
    // do some stuff....
}

---

Here is your json:

{
    "syncresponse": {
       "synckey": "2011-09-30 14:52:00",
        "createdtrs": [

        ],
        "modtrs": [

        ],
        "deletedtrs": [
          {
           "companyid": "UTB17",
           "username": "DA",
           "date": "2011-09-26",
           "reportid": "31341"
      }
       ]
   }
}

and it's parsing:

JSONObject object = new JSONObject(result);
String syncresponse = object.getString("syncresponse");
JSONObject object2 = new JSONObject(syncresponse);
String synckey = object2.getString("synckey");
JSONArray jArray1 = object2.getJSONArray("createdtrs");
JSONArray jArray2 = object2.getJSONArray("modtrs");
JSONArray jArray3 = object2.getJSONArray("deletedtrs");
for(int i = 0; i < jArray3 .length(); i++)
{
   JSONObject object3 = jArray3.getJSONObject(i);
   String comp_id = object3.getString("companyid");
   String username = object3.getString("username");
   String date = object3.getString("date");
   String report_id = object3.getString("reportid");
}

---

JSONArray deletedtrs_array = sync_reponse.getJSONArray("deletedtrs");

for(int i = 0; deletedtrs_array.length(); i++){

            JSONObject myObj = deletedtrs_array.getJSONObject(i);
}

---

{"syncresponse":{"synckey":"2011-09-30 14:52:00","createdtrs":[],"modtrs":[],"deletedtrs":[{"companyid":"UTB17","username":"DA","date":"2011-09-26","reportid":"31341"}]

The get companyid, username, date;

jsonObj.syncresponse.deletedtrs[0].companyid
jsonObj.syncresponse.deletedtrs[0].username
jsonObj.syncresponse.deletedtrs[0].date

---

start from

JSONArray deletedtrs_array = sync_reponse.getJSONArray("deletedtrs");

you can iterate through JSONArray and use values directly or create Objects of your own type
which will handle data fields inside of each deletedtrs_array member

Iterating

for(int i = 0; i < deletedtrs_array.length(); i++){
    JSONObject obj = deletedtrs_array.getJSONObject(i);
    Log.d("Item no."+i, obj.toString());

    // create object of type DeletedTrsWrapper like this
    DeletedTrsWrapper dtw = new DeletedTrsWrapper(obj);

    // String company_id = obj.getString("companyid");
    // String username = obj.getString("username");
    // String date = obj.getString("date");
    // int report_id = obj.getInt("reportid");
}

Own object type

class DeletedTrsWrapper {

    public String company_id;
    public String username;
    public String date;
    public int report_id;

    public DeletedTrsWrapper(JSONObject obj){
        company_id = obj.getString("companyid");
        username = obj.getString("username");
        date = obj.getString("date");
        report_id = obj.getInt("reportid");
    }
}

---

When using google gson library.

var getRowData =
[{
    "dayOfWeek": "Sun",
    "date": "11-Mar-2012",
    "los": "1",
    "specialEvent": "",
    "lrv": "0"
},
{
    "dayOfWeek": "Mon",
    "date": "",
    "los": "2",
    "specialEvent": "",
    "lrv": "0.16"
}];

    JsonElement root = new JsonParser().parse(request.getParameter("getRowData"));
     JsonArray  jsonArray = root.getAsJsonArray();
     JsonObject  jsonObject1 = jsonArray.get(0).getAsJsonObject();
     String dayOfWeek = jsonObject1.get("dayOfWeek").toString();

// when using jackson library

    JsonFactory f = new JsonFactory();
              ObjectMapper mapper = new ObjectMapper();
          JsonParser jp = f.createJsonParser(getRowData);
          // advance stream to START_ARRAY first:
          jp.nextToken();
          // and then each time, advance to opening START_OBJECT
         while (jp.nextToken() == JsonToken.START_OBJECT) {
            Map<String,Object> userData = mapper.readValue(jp, Map.class);
            userData.get("dayOfWeek");
            // process
           // after binding, stream points to closing END_OBJECT
        }

---

Make use of Android Volly library as much as possible. It maps your JSON reponse in respective class objects. You can add getter setter for that response model objects. And then you can access these JSON values/parameter using .operator like normal JAVA Object. It makes response handling very simple.