How to check JSON is empty in Android?

Question

I am developing an Android Application which Fetch data from PHP Json.

I fetch the data of json successfully From JSON but my problem is when JSON is Empty it stops the application.

So I need to Know is How to know if the JSON is NULL or Return Nothing in ANDROID.

My empty JSON is:

[[]]

How to check that with Coding.

Please send me your suggestions.

My Full Code is On This Link:

Thanks Alot

How are you parsing it? any third party libray or default parser? — amalBit, Apr 05 '14 at 05:51
At which part is it stopping your application..? while parsing or after that? — amalBit, Apr 05 '14 at 05:55
jsonObj = jsonArray.getJSONObject(0); stops And error is JsonObj can not converted in JSONARRAY — Nirav Dabhi, Apr 05 '14 at 06:00
Use catch (JSONException e) .. if till u are facing same prob than Please post your code here .. — Subhalaxmi, Apr 05 '14 at 08:35
http://stackoverflow.com/questions/22808148/what-is-the-meaning-of-org-json-jsonexception-in-android My Code is here in my prev que. please check it out — Nirav Dabhi, Apr 05 '14 at 08:53

Abhinav · Answer 1 · 2014-04-05T05:55:35.493

2

JSONObject myJsonObject = 
    new JSONObject("{\"null_object_1\":[],\"null_object_2\":[null]}");

if (myJsonObject.getJSONArray("null_object_1").length() == 0) {
    ... 
}

edited Apr 05 '14 at 05:55

answered Apr 05 '14 at 05:53

Abhinav

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M getting null array in json as a output [[]]] then How it can be checked if no data found – Nirav Dabhi Apr 05 '14 at 05:59

score 2 · Answer 2 · answered Apr 05 '14 at 06:06

2

firstly you get key set of json.

 Iterator<Object> keys = json.keys();

then check if any key exist then your json contain some value.

if(keys.hasNext()){ // json has some value

} else { // json is empty. }

answered Apr 05 '14 at 06:06

Yogendra

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what is json? JSONObject or JSONArray? I cant Pass keys to JSONObject – Nirav Dabhi Apr 05 '14 at 06:08
I cant pass keys to JSONObject. Error is Cannot make a static reference to the non-static method keys() from the type JSONObject – Nirav Dabhi Apr 05 '14 at 06:12
read this link it will help http://stackoverflow.com/questions/10154090/android-get-json-key-value – Yogendra Apr 05 '14 at 06:15

score 1 · Answer 3 · edited Apr 05 '14 at 06:23

1

try like this,

if (<Your JSONobj>!= null ){
    // do your parsing 
}else{

}

edited Apr 05 '14 at 06:23

Balder

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answered Apr 05 '14 at 05:53

Aerrow

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I m parsing the data from JSON to listview so if I check this condition first i initialise jsonobj=null; then how it works – Nirav Dabhi Apr 05 '14 at 05:58

score 1 · Answer 4 · edited Apr 05 '14 at 06:02

1

after getting json from url first check for null by simply execute the code:-

if(yourjsonobject!=null){

//write your code here

}else{e
enter code here
//json is null
}

edited Apr 05 '14 at 06:02

Abhinav

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answered Apr 05 '14 at 05:56

user3436202

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2

vijay_t · Answer 5 · 2014-04-05T07:52:16.303

1

1) json string "[[]]" means not empty jsonAarray it means your Outer JsonArray contains one element as JsonArray and your inner JsonArray is empty.

2) The reason your application is crashing/stopping is that JsonObject and JsonArray are incomptible types. You can not cast JsonArray to JsonObject. See JsonArray and JsonObject

3) You can always check the length of your JsonArray by JsonArray#length() method. also check JsonArray#isNull if want to check wheter a JsonObject is NULL.

try {
    JSONArray object = new JSONArray("[[]]");
    if (object.length() > 0) {
        JSONArray inner = object.getJSONArray(0);
        if (inner.length() > 0) {
        // do something         
        }
    }           
} catch (JSONException e) {
    e.printStackTrace();
}

edited Apr 05 '14 at 07:52

answered Apr 05 '14 at 07:23

vijay_t

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Got The error cannot convert from JSONArray to JSONObject – Nirav Dabhi Apr 05 '14 at 08:42
Please see the link in my question I had already posted the code in my prev question – Nirav Dabhi Apr 05 '14 at 09:15

How to check JSON is empty in Android?

My empty JSON is:

5 Answers5