How can i check my json mainobject has it's sub-objects or not in android?

Question

Here is my json file

{
    status: true,
    version: "2.0.3",
    status_code: 200,
    expires: "1458121027.0",
    Etag: "1458121027.0",
    cache_key: "match|icc_wc_t20_2016_g14|overs_summary",
    data: {
        batting_order: [
            [
                "a",
                "1"
            ]
        ],
        innings: { }
    }
}

In which i was tried to get innings object of data object parent. It means data.innings

I put the condition like below

if(!data.isNull("innings") && data.has("innings")) {
    innings = data.getJSONObject("innings");
    inn_arr=innings.names(); 

    if (inn_arr.length() != 0) {//I got error over here.
        try {
            for (int i = 0; i < inn_arr.length(); i++) {
                if (inning_name.equals(inn_arr.getString(i))) {
                    inn_obj = innings.getJSONObject(inn_arr.getString(i));
                    if (inn_obj.has("overs_summary") && !inn_obj.isNull("overs_summary")) {
                        JSONArray over_summary = inn_obj.getJSONArray("overs_summary");
                        for (int j = over_summary.length() - 1; j >= 0; j--) {
                            JSONObject over_obj = over_summary.getJSONObject(j);
                            over_arr.add(over_obj);
                        }
                    }
                }
            }
        } catch (NullPointerException ne) {
            ne.printStackTrace();
        }
    }

}

In above code my app is crashed because of it not having the length.

score 1 · Accepted Answer · edited Jun 20 '20 at 09:12

1

add if inn_arr is null

innings = data.getJSONObject("innings");
inn_arr = innings.names();
if (inn_arr != null && inn_arr.length() > 0) {
    //...
}

If you want to get key set from JSONObject then you can use two methods

innings.names() Returns an array containing the string names in this object. This method returns null if this object contains no mappings.

innings.keys() Returns an iterator of the String names in this object.

So you can use Iterator<String> iterator = innings.keys(); method and iterate over it to avoid NullPointerException.

Reference from this

edited Jun 20 '20 at 09:12

Community

1
1

answered Mar 16 '16 at 10:46

ELITE

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3
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when mainobject.has not having any kind of sub object then? – Milan Gajera Mar 16 '16 at 10:47
check it my post in which inning does not having any sub-object. – Milan Gajera Mar 16 '16 at 10:47
post your `LogCat` – ELITE Mar 16 '16 at 10:49

score 1 · Answer 2 · answered Mar 16 '16 at 10:49

1

Add a check(if (inn_arr != null)) whether inn_arr is null or not before if (inn_arr.length() != 0).

answered Mar 16 '16 at 10:49

Febi M Felix

2,799
1
10
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i got inn_arr as null therefor i got an exception like null pointer exception. – Milan Gajera Mar 16 '16 at 10:51
Exactly. Your innings object is null. – Febi M Felix Mar 16 '16 at 10:52

How can i check my json mainobject has it's sub-objects or not in android?

2 Answers2