CODEWITHSUNDEEP
javaandroidjson
ROJ
ROJ

Reputation: 57

Extract data from JSON string android

I'm trying to extract data from Github Sample Collection of Books but i am getting a blank screen. here is my JSON parsing code.

try {

        JSONObject bookObject = new JSONObject(SAMPLE);
        JSONArray booksArray = bookObject.getJSONArray("books");

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

           JSONObject currentBook = booksArray.getJSONObject(i);

           String title =  currentBook.getString("title");
           String author = currentBook.getString("author");
           String isbn = currentBook.getString("isbn");

           Book book = new Book(title,author,isbn);
           books.add(book);
        }

}catch (JSONException e){
        Log.e("QueryUtils", "Problem parsing the earthquake JSON results", e);
}

Upvotes: 2

Views: 2456

Answers (4)

andOrNot
andOrNot

Reputation: 47

Try this : 

    Gson gson = new Gson();

    JSONObject o = new JSONObject(jsonData.toString()); // pass your data here
    JSONArray arr = new JSONArray(o.get("books").toString());

    List<Book> books = new ArrayList<Book>();

    for (int i = 0; i < arr.length(); i++) {
        Book book = gson.fromJson(arr.get(i).toString(), Book.class);
        books.add(book);
    }

I have used Gson library here. There are other libraries as well. Refer this link for more details: http://tutorials.jenkov.com/java-json/gson-jsonparser.html

Upvotes: 2

Mohamed Niyaz
Mohamed Niyaz

Reputation: 228

you need to convert the response from the network service to string and then get the jsonArray it will work

Like this ::

@Override
public void onResponse(Call call, final okhttp3.Response response) throws IOException {
                    final String stringResponse = response.body().string();
                    //insted of sample pass the stringresponse it will work
                    JSONObject bookObject = new JSONObject(stringResponse);
                    JSONArray booksArray = bookObject.getJSONArray("books");

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

                JSONObject currentBook = booksArray.getJSONObject(i);

               String title =  currentBook.getString("title");
               String author = currentBook.getString("author");
               String isbn = currentBook.getString("isbn");

                Book book = new Book(title,author,isbn);
                books.add(book);
            }
            });

Upvotes: 1

Mayur Coceptioni
Mayur Coceptioni

Reputation: 443

Check your model class , in that you set the parameters.

Upvotes: 0

Tlaloc-ES
Tlaloc-ES

Reputation: 5282

I recommend to you use GSON, is very easy library

To Json

Gson gson = new Gson();

Staff obj = new Staff();

// 1. Java object to JSON file
gson.toJson(obj, new FileWriter("C:\\projects\\staff.json"));

// 2. Java object to JSON string
String jsonInString = gson.toJson(obj);

From Json

Gson gson = new Gson();

// 1. JSON file to Java object
Staff staff = gson.fromJson(new FileReader("C:\\projects\\staff.json"), Staff.class);

// 2. JSON string to Java object
String json = "{'name' : 'mkyong'}";
Staff staff = gson.fromJson(json, Staff.class);

// 3. JSON file to JsonElement, later String
JsonElement json = gson.fromJson(new FileReader("C:\\projects\\staff.json"), JsonElement.class);
String result = gson.toJson(json);

If you want to see more information about this you can check this link: https://www.mkyong.com/java/how-do-convert-java-object-to-from-json-format-gson-api/

Upvotes: 4

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