Checking JSON Output

Question

i currently wrote a php script that is linked to my android application however i have a question : MY php script have 2 outputs:

["Success"]
null

When output is null i want in my android application:

if (json.equals(null)) {
    goodrating.setVisibility(View.GONE);
    badrating.setVisibility(View.GONE);

if output is ["Success"] i want my android app to do :

    } else {
 goodrating.setVisibility(View.VISIBLE);
 badrating.setVisibility(View.VISIBLE);

        }

PROBLEM IS NOT SOLVED YET

UPDATE HERE'S MY FULL CODES THROUGH ASYNCTASK:

protected String doInBackground(String... params) {
if (fb.isSessionValid()) {
                    String resulta;
                    JSONObject obj = null;
                    String jsonUser = fb.request("me");
                    obj = Util.parseJson(jsonUser);
                    String email = obj.optString("email");

                    String phonename = prefs.getString("esmlphone", "value");
                    InputStream isr = null;
                    HttpClient httpclient = new DefaultHttpClient();
                    String tablename = prefs.getString("hazahuwakeylurl",
                            "walashi");
                    HttpPost httpost = new HttpPost(
                            "secret");
                    HttpResponse resposne = httpclient.execute(httpost);
                    HttpEntity entity = resposne.getEntity();
                    isr = entity.getContent();
                    BufferedReader reader = new BufferedReader(
                            new InputStreamReader(isr, "UTF-8"), 8);
                    StringBuilder sb = new StringBuilder();
                    String line = null;
                    while ((line = reader.readLine()) != null) {
                        sb.append(line + "\n");
                    }
                    isr.close();
                    resulta = sb.toString();
                    final JSONArray jArray = new JSONArray(resulta);
                    try {
                        for (int i = 0; i < jArray.length(); i++) {
                            JSONObject json = jArray.getJSONObject(0);
                            if (json.isNull("response")) {
                                goodrating.setVisibility(View.GONE);
                                badrating.setVisibility(View.GONE);
                            } else {
                                goodrating.setVisibility(View.VISIBLE);
                                badrating.setVisibility(View.VISIBLE);
                            }
                        }

                    } catch (Exception e) {
                        Log.d("visibility", e.toString());
                    }
                }

            return null;

        }

score 1 · Answer 1 · answered Jul 16 '13 at 02:41

Problems

"null" is not valid JSON, however, [null] is. Check http://jsonlint.com/
According to your exception, you're converting a string to a JSON object. So I'm guessing jArray is simply an array of your response. You should be converting your response to a JSON array or object first.
Once you have #2 all settled, http://developer.android.com/reference/org/json/JSONArray.html#isNull(int) is the proper way of checking whether a JSONObject in a JSONArray is null.

bodecker · Answer 2 · 2013-07-15T23:14:16.197

~~Try if (json == null). That's usually how you check for null objects in Java.~~

edit: This is because most 'Objects' in Java are actually just references to the data structures themselves. You use == null check if the reference is null, and use .equals() to determine if an object is logically equivalent to another object.

One more try - it looks like there's a JsonValue.NULL constant in the JsonObject class. Try if (json == JsonValue.NULL)

score 0 · Answer 3 · answered Jul 15 '13 at 23:11

0

So what you'll want to do is this:

if(json.isNull("response"))
    goodrating.setVisibility(View.GONE);
    badrating.setVisibility(View.GONE);
} else if(json.getString("response").equals("Success")){
    goodrating.setVisibility(View.VISIBLE);
    badrating.setVisibility(View.VISIBLE);
}

answered Jul 15 '13 at 23:11

Anubhaw Arya

145
6

Awesome, glad I could help! Do us all a favor though and mark this as an accepted answer if it solves your problem so everyone knows this question has been answered. – Anubhaw Arya Jul 16 '13 at 15:16
So then what exactly is the issue? I see the code update, but you're not saying anything else as to what is wrong... – Anubhaw Arya Jul 16 '13 at 22:23

score 0 · Answer 4 · answered Jul 16 '13 at 22:25

So when you hit the website, is does it ONLY output ["Success"] or null? If that's the case, its not json what you're outputting. What you want to output is something like this:

{
    "response": "Success"
}

or

{
    "response": null
}

Only then will the JSON on the Android end will work properly

Checking JSON Output

4 Answers4