CODEWITHSUNDEEP
javaandroidjson
Johan
Johan

Reputation: 35223

get json from HttpResponse

HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://my.server:8080/android/service.php");


List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
nameValuePairs.add(new BasicNameValuePair("action", "getjson"));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

HttpResponse response = httpclient.execute(httppost);

service.php generates a json string. How would i fetch it from my response? Btw; I've icluded the GSON library, can i make use of any methods in it perhaps?

Solutions similar to this one looks pretty ugly, imo: best way to handle json from httpresponse android

There much be better ways, right?

Any help is appreciated, thanks

Update:

String json = EntityUtils.toString(response.getEntity());

seems to do the trick. There is just one small issue: The string is wrapped with brackets []. Should i remove them manually? They are generated by php:s json_encode()

Upvotes: 33

Views: 112063

Answers (4)

MikeN
MikeN

Reputation: 46387

I think the problem you are running into is one similar to my own I just ran into. If you run:

String json_string = EntityUtils.toString(response.getEntity());
JSONObject temp1 = new JSONObject(json_string);

The above code will throw an exception and it looks like the JSON array brackets are to blame. But it's fine to have a JSON array as the top level element! You just need to use JSONArray() instead of JSONObject:

String json_string = EntityUtils.toString(response.getEntity());
JSONArray temp1 = new JSONArray(json_string);

So you have to know if you are getting a JSONArray or a single dictionary that is a JSONObject in your JSON code.

If you are used to the iOS/Objective-C JSON parsing libraries they use the same top level element to deal with json dictionaries and json array's, so moving to the JAVA / Android world confused me about having two types for handling JSON depending on the top level returned.

Upvotes: 27

Johan
Johan

Reputation: 35223

The problem was in my php file. Removing the container array from the json encoded object made my java code work.

Upvotes: 1

user742030
user742030

Reputation:

With this class, you can get the JSON data from either from a server or from your assets folder. It can be easily changed to only one or the other. If you need a Adapter use the one jgilfelt created here on getHub.

@Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

        Bundle getArgs = this.getArguments();
        String URI = getArgs.getString(KEY_URI);//OR YOU CAN HARD CODE THIS OR GET THE STRING ANYWAY YOU LIKE.

        new GetJSONTask().execute(URI);
    }

    class GetJSONTask extends AsyncTask<String, Integer, String> {

        protected String doInBackground(String... arg0) {

            String uri = arg0[0];

            InputStream is = null;

            if (uri.contains("http") == true) {// Get JSON from URL
                try {
                    DefaultHttpClient httpClient = new DefaultHttpClient();
                    HttpPost httpPost = new HttpPost(uri);
                    HttpResponse httpResponse = httpClient.execute(httpPost);
                    HttpEntity httpEntity = httpResponse.getEntity();
                    is = httpEntity.getContent();

                    BufferedReader rd = new BufferedReader(new InputStreamReader(is, "UTF-8"));
                    while ((line = rd.readLine()) != null) {
                        json += line;
                    }
                    rd.close();
                    return json;
                } catch (Exception e) {
                    e.printStackTrace();
                    return null;
                }
            } else {// Get JSON from Assets

                Writer writer = new StringWriter();
                char[] buffer = new char[1024];

                try {
                    InputStream jsonFile = getActivity().getAssets().open(uri);
                    Reader reader = new BufferedReader(new InputStreamReader(jsonFile, "UTF-8"));
                    int n;
                    while ((n = reader.read(buffer)) != -1) {
                        writer.write(buffer, 0, n);
                    }
                    jsonFile.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                json = writer.toString();
                // return JSON String
                return json;
            }
        }

        @Override
        protected void onPostExecute(String result) {
            try {
                showData(result);
            } catch (JSONException e) {
                e.printStackTrace();
                Toast.makeText(getActivity(), "something went wrong", Toast.LENGTH_SHORT).show();
            }
        }
    }

    private void showData(String json) throws JSONException {
        JSONObject o = new JSONObject(json);
        JSONArray data = o.getJSONArray("results");
    }
}

Upvotes: 2

John J Smith
John J Smith

Reputation: 11941

If I'm returning a JSON string from my web service, I usually want to get it back to a JSON object like so:

String response = client.getResponse();

    if (responseCode == 200)
    {                   
         JSONObject obj = new JSONObject(response);                                                             
    }

Upvotes: 1

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