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Android Json parsing with sqlite

I am new in android JSON parsing android.
Below I mentioned my JSON value, please give the solution to how to parse the JSON value, thanks in advance my JSON Data:
Here I have category, categorybook, subcategory inside have subbook. I want to parse all the value and store it into sqlite with separate.
Like category book and sucategory book are stored seperate column in android sqlite table:
[
"category": {
"id": "1",
"name": "Education",
"categorybooks": [],
"subcategory": [
{
"id": "1",
"name": "tamil",
"subcategorybooks": []
},
{
"id": "2",
"name": "english",
"subcategorybooks": []
},
{
"id": "5",
"name": "maths",
"subcategorybooks": []
},
{
"id": "6",
"name": "science,
"subcategorybooks": []
},
{
"id": "7",
"name": "social",
"subcategorybooks": []
}
}
]
Here i have category 2 and its sub category books:
[
"category": {
"id": "2",
"name": "sports",
"categorybooks": [
{
"id": "4",
"name": "football",
},
{
"id": "5",
"name": "cricket",
}
],
"subcategory": []
}
]

First of all, you will need the VolleyLibrary. Then, you will need the GSON library. When creating GSON Request, you put the Object you want to get deserialized automatically from JSON, so you wont have to parse it manualy.
Second thing, you would want to create a db class that extends SQLiteHelper. When you create database, add the methods for adding, update and removing a row for every table that you create.
Below are the links that you need.
http://www.androidhive.info/2014/05/android-working-with-volley-library-1/
https://medium.com/android-news/android-networking-i-okhttp-volley-and-gson-72004efff196#.wp5lstsfv
http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/

I will assume you already have the content of your json, if not you can use any Http Connection to get the content.
You can use Gson to parse your json content, first of all, you need to create your models based on your Json:
//note: Gson identify the attributes name as the same of from your
//json, if not you have to put an annotation above each attribute of
//your class:
public class Category(){
int id;
String name;
List<CategoryBook> categoryBooks;
}
public class CategoryBook(){
int id;
String name;
}
public class SubCategory(){
//Based on your json I will assume the attribute of this class
// is a model that have a list of an object that have an id and a name
//and a list of subcategorybooks
}
public class SubCategoryBooks(){
//class attributes that you not mentioned in your json
}
Then you just need to parse your object from content using gson,
if you have some doubts about how to parse using Gson follow this tutorial
For insert into database separate, you already have your objects with getters and setters, for example
you can get the List<CategoryBook> from your CategoryModel, then your can insert this list
inside a separate table of your database.

Hope It's Help you
JSONObject jsonObject = new JSONObject();
jsonObject.put("category",loaddata());
public JSONObject loaddata(){
JSONObject jsonObject = new JSONObject();
jsonObject.put("id","1");
jsonObject.put("name","Education");
jsonObject.put("categorybooks",addcategorybooks());
jsonObject.put("subcategory","addsubcategory()");
return jsonObject;
}
public JSONArray addcategorybooks(){
JSONArray JsonArray = new JSONArray();
JSONObject jObj = new JSONObject();
jObj.put("id", "1");
jObj.put("name", "Foot Ball");
JsonArray.put(jObj);
return JsonArray;
}
public JSONArray addsubcategory(){
JSONArray JsonArray = new JSONArray();
JSONObject jObj = new JSONObject();
jObj.put("id", "1");
jObj.put("name", "Foot Ball");
jObj.put("subcategorybooks", addsubcategorybooks());
JsonArray.put(jObj);
return JsonArray;
}
public JSONArray addsubcategorybooks(){
JSONArray JsonArray = new JSONArray();
JSONObject jObj = new JSONObject();
jObj.put("id", "1");
jObj.put("name", "Foot Ball");
JsonArray.put(jObj);
return JsonArray;
}

If i understood you correctly, the main problem is to get java model object from json.
There are several ways to do it. The most common are:
Using built-in tools to operate with Json. In this case you get org.json.JSONObject and get values using it's methods. See details f.e. here
Using gson library. In this case you create model class and you can fill the object with one code line. smth like Category category = gson.fromJson(yourJsonString, Category.class); See details in official tutorial

Nested Json parsing using Gson

I have tried to parse this JSON using gson but I couldn’t.
Can anyone help me to parse this JSON using gson?
JSON:
{
"status": "ok",
"results": {
"favourites": [
{
"id": "UB3172",
"name": "Masdar Headquarters"
},
{
"id": "UB1438",
"name": "Guggenheim Abu Dhabi on Saadiyat Island"
},
{
"id": "UB4838",
"name": "Watani Residential Development in Abu Dhabi - 600 Villas and 48 Buildings"
},
{
"id": "UB4795",
"name": "Two Mosques in Mohammed Bin Zayed City"
},
{
"id": "UB1274",
"name": "2 Workers Residential City at Al Ain Industrial City"
}
]
}
}
I tried this one for JSON parser class:
public class ProjectList {
public String status;
public String results;
public class Favourites{
public String id;
public String name;
}
}
In MainActivit
Reader reader = new InputStreamReader(result);
Gson gson=new Gson();
List<ProjectList.Favourites> fav=new ArrayList<ProjectList.Favourites>();
fav=Arrays.asList(gson.fromJson(reader, ProjectList.Favourites.class));

Create a POJO class as follows
class MyResponse {
public String status;
public Result results;
public static class Favourites {
public String id;
public String name;
}
public static class Result {
public List<Favourites> favourites;
}
}
and pass it to gson as
MyResponse response = new Gson().fromJson(yourResponse, MyResponse.class);
idea is that maintain the hierarchy of key-value pairs with appropriate POJO's

You can generate your pojos here : http://www.jsonschema2pojo.org/
Sometimes gson cannot convert your objects from json. In this case you have to write your own deserializer and use it with gson builder.
Edit: If you use proguard before release your project (if you set proguard to change your pojos variable names) gson cannot match class variable names, json names so it cannot convert your objects. You have to add #SerializedName("your_variable_name") annotaion.

Try this way,hope this will help you to solve your problem.
String jsonRespone = "{\"status\":\"ok\",\"results\":{\"favourites\":[{\"id\":\"UB3172\",\"name\":\"Masdar Headquarters\"},{\"id\":\"UB1438\",\"name\":\"Guggenheim Abu Dhabi on Saadiyat Island\"},{\"id\":\"UB4838\",\"name\":\"Watani Residential Development in Abu Dhabi - 600 Villas and 48 Buildings\"},{\"id\":\"UB4795\",\"name\":\"Two Mosques in Mohammed Bin Zayed City\"},{\"id\":\"UB1274\",\"name\":\"2 Workers Residential City at Al Ain Industrial City\"}]}}";
String status;
ArrayList<HashMap<String,String>> favouritesList = new ArrayList<HashMap<String, String>>();
try{
JSONObject responseJson = new JSONObject(jsonRespone);
status = responseJson.getString("status");
JSONArray favouriteJsonArray = responseJson.getJSONObject("results").getJSONArray("favourites");
for (int i=0;i<favouriteJsonArray.length();i++){
HashMap<String,String> favourite = new HashMap<String, String>();
favourite.put("id",favouriteJsonArray.getJSONObject(i).getString("id"));
favourite.put("name",favouriteJsonArray.getJSONObject(i).getString("name"));
favouritesList.add(favourite);
}
System.out.print("status : "+status);
for (HashMap<String, String> favourite : favouritesList) {
System.out.print("id : "+favourite.get("id"));
System.out.print("name : "+favourite.get("name"));
}
}catch (Throwable e){
e.printStackTrace();
}

Parsing JSON file with different number of keys

My JSON file contains strings with the same keys but some of them doens't appear for some strings. For example:
{
"city": "CB1 2BH Cambridge",
"addr": "Devonshire Road 1",
"title": "Devonshire Arms",
"phone": "+44 1223 6610"
},
{
"city": "E8 1JH London",
"addr": "Amhurst Road 90",
"title": "Pembury Tavern",
"web": "http://www.individualpubs.co.uk/pembury/"
},
{
"web": "http://bandholmhotel.dk/",
"title": "Bandholm Hotel",
},
{
"city": "00100 Helsinki",
"addr": "Pohjoinen Rautatiekatu 23",
"title": "Helkan Baari",
"country": "FI"
},
How to correctly parse it in android?

Considering this is your JSONArray,
Try to do as following,
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jObj = (JSONObject) jsonProductArray.getJSONObject(i);
String city = jObj.optString("city", "cityDefaultValue");
String addr = jObj.optString("addr", "addDefaultValue");
String title = jObj.optString("title", "titleDefaultValue");
String phone = jObj.optString("phone", "phoneDefaultValue");
}

One possible solution can be to have a modal class and use Gson library to parse the Json.
You can set some default values in your modal class, for keys whose value is not found in Json

Create an model class with the key of the json and parse it to the model class using gson.
A a = gson.fromJson(jsonRes.toString(),A.class);
here A is your model class and a is the instance of A

You can use Gson library.
Create something like that
class SomeObjects {
#SerializedName("city")
private String mCity;
#SerializedName("addr")
private String mAddres;
...
}
and in then
SomeObject obj = new Gson.fromJson(jsonString, SomeObject.class);
You also can sirialize right into array

Parsing JSON file in Android Application

How would I parse the following string in Android?
{
"C1": {
"name": "first name",
"address": "first address",
"lat": 36.072111,
"lng": 34.732112
},
"C2": {
"name": "second name",
"address": "second address",
"lat": 32.02132,
"lng": 34.000002
},
"C3": {
"name": "third name",
"address": "third address",
"lat": 37.05435,
"lng": 34.75703
}
}
I can't understand. Is it an objects inside of an object structure? How would this be parsed? How do I find how many objects I have?

Well, got it. the solution is to first get the names of the inner-objects:
JONObject json = new JSONObject(jsonString);
JSONArray namesArray = json.names();
which will give you an JSONArray of the existing objects inside.
Then run on it's objects to get each one of them:
for (int i = 0 ; i < namesArray.length() ; i ++)
{
currentObject = json.getJSONObject(namesArray.get(i).toString());
Log.d("TAG", "currentObject : "+currentObject.toString());
addCurrentObjectShopToObjectsListUsingGson(currentObject,objectsList);
}

You can use JSONObject to extract the contents of the structure.
An example can be shown below:
You can retrieve a JSONArray from your string with
JSONObject json = new JSONObject(jsonString);
JSONArray myArray = json.getJSONArray(ARRAY_NAME_HERE);
After doing so, you can extract the name of a person with
JSONObject person = myArray.getJSONObject(0); // retrieve the first person
String name = person.getString("name"); // get the person's name
Reference:
http://developer.android.com/reference/org/json/JSONObject.html

The string you've shown contains an outer object with 3 inner objects. Suppose you want to get C1.name. You would do this:
JSONObject root = new JSONObject(yourString);
JSONObject c1 = root.getJSONObject("C1");
String name = c1.getString("name");
However, I should point out one other thing, which is that the original string you are using is odd because it suggests that what you really want is an array. The code to parse would be different, of course, and involve JSONArray, but I think a better representation would look like this:
[
{"name":"first name","address":"...","lat":"...","lng":"..."},
{"name":"second name"...},
{"name":"third name"...}
]
So in this case, the outermost container is a JSONArray, not an object.

You need a "model" object that looks like this: (provided the hash is static).
public class TheCs extends BaseModel {
public OneC c1;
public OneC c2;
public OneC c3;
}
public class OneC extends BaseModel {
public String name;
public String address;
public float lat, lng;
}
public class BaseModel implements Serializable {
private static final long serialVersionUID = 1L;//use a random number here
}
Now when parsing with Gson, pass TheCs.class as the type.
If the Hash is not static you could (and Gson will do the right thing as far as I can remember), do something like:
public class TheCs extends BaseModel {
public List<OneC> someHash;
}

Android code For Following JSON Pattern

Want Android Code For Following JSON Format...Bit Confused How to fetch value of array For Following Pattern..
{
"params": [
{
"answer_data_all": [
{
"id": "5",
"question_id": "14"
}
],
"form_data_all": [
{
"id": "1",
"name": "form 1"
}
]
}
]
}

You just have some nested JSONArray and JSONObject. Assuming you have this response in string format all you have to do is create JSONObject from that string and then extract what you need. As someone mentioned [ ] encloses JSONArray while { } encloses JSONObject
JSONObject mainObject = new JSONObject(stringResponse);
JSONArray params = mainObject.getJSONArray("params"); //title of what you want
JSONObject paramsObject = params.getJSONObject(0);
JSONArray answerData = paramsObject.getJSONArray("answer_data_all");
JSONArray formData = paramsObject.getJSONArray("form_data_all");
String id = formData.getJSONObject(0).getString("id");
You should be able to extract all the values doing something like this. Although I will say I think the formatting is odd. You're using single member arrays that just contain other objects. It would make much more sense to either use one array to hold all the object or just separate JSONObject. It makes it much easier to read and easier to parse.

Parsing a JSON is fairly simple. You could use GSON library by Google for example. Below is an example I wrote for your object/model:
class MyObject{
ArrayList<Params> params;
class Params {
ArrayList<AnswerData> answer_data_all;
ArrayList<FormData> form_data_all;
class AnswerData {
String id;
String question_id;
}
class FormData {
String id;
String name;
}
}
}
And then get an instance of your object with:
MyObject myObject = (MyObject) (new Gson()).toJson("..json..", MyObject.class);

JSONArray feed = feedObject.getJSONArray("params");
for(int i = 0; i<feed.length(); i++){
JSONArray tf = feed.getJSONArray(i);
for (int j = 0; j < tf.length(); j++) {
JSONObject hy = tf.getJSONObject(j);
String idt = hy.getString("id");
String name = hy.getString("name");
}
}
**NOTE: the 'feedObject' variable is the JSONObject you are working with..Although this your type of JSON feed is kinda mixed in terms of string names and all but this should do for now..