Develop Reference

How to use volley in android to extract specific json?

If my request returns a JSON object like this
{"autocomplete":["abc", "asd"]}
How can I get the array in the JSON and turn it into java ArrayList?
I find some methods like getString, getInt. But I don't find a method that could get the array.

val response = JSONObject(yourresponse)
val Jarray: JSONArray = response.getJSONArray("autocomplete")
for (i in 0 until Jarray.length()) {
val jsonobject: JSONObject = jsonarray.getJSONObject(i)
Log.e("TAG",jsonobject.toString())
}
In this way you can do

String response = new JSONObject(response);
JSONArray array= c.getJSONArray("autocomplete");
for (int i = 0; i < array.length(); i++){
JSONObject a = carteVisite.getJSONObject(j);
Log.d("TAG", a);
}

Getting attribute values from JSON String in Java

Hello I am building a Spring Boot app with Thymeleaf and I am receiving from an API a JSON that I have to put in the HTML page. This is the JSON:
{"mesaje":[{"data_creare":"202205191249","cif":"1111111111118","id_solicitare":"205804","detalii":"Erori de validare identificate la factura primita cu id_incarcare=205804","tip":"ERORI FACTURA","id":"9279339"}
This is what I have tried:
String raspuns = service.getListaMesaje(zile, select);
System.out.println("------------------------"+raspuns);
JsonParser parser = new JsonParser();
JsonObject obj = parser.parse(raspuns).getAsJsonObject();
//String eroare = obj.get("eroare").getAsString();
String mesaje = obj.get("mesaje").getAsString();
JSONObject responseObject = new JSONObject(raspuns);
JSONArray jsonArray = (JSONArray) responseObject.get("mesaje");
JSONObject jsonObject = (JSONObject) jsonArray.get(0);
String dataCreare = jsonObject.getString("data_creare");
model.addAttribute("data_creare", dataCreare);
In the console the JSON prints but I get this error also in the console:
java.lang.IllegalStateException: null
Can someone show me an example how to extract the values from mesaje parent in the JSON ?
Thank you

I suggest you to use gson library for that.
Then, after you added gson dependency in pom.xml, you can extract values from your JSON string with this few lines of code :
String raspuns = "{\"mesaje\":[{\"data_creare\":\"202205191249\",\"cif\":\"1111111111118\",\"id_solicitare\":\"205804\",\"detalii\":\"Erori de validare identificate la factura primita cu id_incarcare=205804\",\"tip\":\"ERORI FACTURA\",\"id\":\"9279339\"}]}";
JsonObject jsonObject = new JsonParser().parse(raspuns).getAsJsonObject();
JsonArray arr = jsonObject.getAsJsonArray("mesaje");
for (int i = 0; i < arr.size(); i++) {
String data_creare = arr.get(i).getAsJsonObject().get("data_creare").getAsString();
String cif = arr.get(i).getAsJsonObject().get("cif").getAsString();
String id_solicitare = arr.get(i).getAsJsonObject().get("id_solicitare").getAsString();
String detalii = arr.get(i).getAsJsonObject().get("detalii").getAsString();
String tip = arr.get(i).getAsJsonObject().get("tip").getAsString();
String id = arr.get(i).getAsJsonObject().get("id").getAsString();
System.out.println(data_creare);
System.out.println(cif);
System.out.println(tip);
System.out.println(id_solicitare);
System.out.println(detalii);
System.out.println(id);
}

Reading a JSON Array in JAVA

I'm having a problem reading JSON Array because inside my array, there's another array and I'm confused.Please see my code.
JSONObject jsonObject = JSONFactoryUtil.createJSONObject();
JSONObject obj = JSONFactoryUtil.createJSONObject();
JSONObject jsonObjectReturn = JSONFactoryUtil.createJSONObject();
//JSONOBJECT RETURN
JSONArray array = JSONFactoryUtil.createJSONArray();
for (int i = 0; i < jsonArray.length(); i++) {
obj = jsonArray.getJSONObject(i);
callableStatement = (CallableStatement) conn
.prepareCall("{call TaxpaymentSPv2(?,?,?,?,?,?,?,?)}");
callableStatement.setString(1, obj.getString("rdoCode"));
callableStatement.setString(2, obj.getString("rcoCode"));
callableStatement.setString(3, obj.getString("tpTin"));
callableStatement.setString(4, obj.getString("tpName"));
callableStatement.setString(5, obj.getString("tpAddress"));
callableStatement.setString(6, obj.getString("receiptType"));
callableStatement.registerOutParameter(7, Types.VARCHAR);
callableStatement.registerOutParameter(8, Types.VARCHAR);
callableStatement.executeUpdate();
String rNo = callableStatement.getString(7);
String date = callableStatement.getString(8);
//---->This is my second Array inside my JSON where im having an error <------
String checkArray = obj.getString("checkArray");
JSONArray jsonArrayCheck = JSONFactoryUtil.createJSONArray(stringArray);
JSONArray jsonArray2 = jsonObject.getJSONArray("checkArray");
System.out.println("..........." + jsonArray2);
jsonObjectReturn = JSONFactoryUtil.createJSONObject();
jsonObjectReturn.put("rNo", rNo);
jsonObjectReturn.put("date", date);
array.put(jsonObjectReturn);
}
return array;
Here's my JSON input:
{
"dataArray": [{
"rdoCode": "001",
"rcoCode": "002911",
"tpTin": "200746409",
"tpName": "JOHN DOE",
"tpAddress": "LA CALIFORNIA",
"receiptType":"ROR",
"receiptMode":"AUTO",
"manualReceiptNo":"",
"checkArray":[{
"ptchkNumber": 14546,
"ptchkDate": 2014-01-01,
"ptchkAmount": 5332,
"ptchkStatus": ""
}]
}]
}
I can't parse the "checkArray" object that gives me this error. com.liferay.portal.kernel.json.JSONException: org.json.JSONException: A JSONArray text must start with '[' at 1 [character 2 line 1]. Can someone tell me what to do? Thanks.

You need to change code:
String checkArray = obj.getString("checkArray");
to following code:
JSONArray checkArray = obj.getJSONArray("checkArray");
JSONObject checkObj = checkArray.getJSONObject(0);
int ptchkNumber = checkObj.getInt("ptchkNumber");
because key checkArray is array inside JSON, so you cannot using getString() but getJSONArray() instead.
Update:
To get each object inside array, you can iterate and access each object:
JSONArray checkArray = obj.getJSONArray("checkArray");
JSONObject checkObj;
for (int itemIndex=0, totalObject = checkArray.length(); itemIndex < totalObject; itemIndex++) {
checkObj = checkArray.getJSONObject(itemIndex);
int ptchkNumber = checkObj.getInt("ptchkNumber");
}

get data from Json array in Json array Android Java

Hello how to get data from Json Array in another Json array i have get data till attachments but attachment doesnt work, All code work till attachments how to get data from attachments I need to get "photo_75" from it
Json
"response":{
"count":3,
"items":[
{
"id":3,
"from_id":205110032,
"owner_id":-81865402,
"date":1417672154,
"post_type":"post",
"text":"jjjjASDFGHJKYTRDXCVB",
"attachments":[
{
"type":"photo",
"photo":{
"id":330414711,
"album_id":-7,
"owner_id":205110032,
"photo_75":"http:\/\/cs605116.vk.me\/v605116032\/6325\/3SwTo8j4lJ0.jpg",
"photo_130":"http:\/\/cs605116.vk.me\/v605116032\/6326\/_OZA86FO3Nw.jpg",
"photo_604":"http:\/\/cs605116.vk.me\/v605116032\/6327\/AUtB59708Nw.jpg",
"photo_807":"http:\/\/cs605116.vk.me\/v605116032\/6328\/59oAdfz9jgI.jpg",
"width":538,
"height":807,
"text":"",
"date":1399134687,
"access_key":"7297eb663de2e4e6b2"
}
}
],
"comments":{
"count":0
},
"likes":{
"count":0
},
"reposts":{
"count":0
}
},
Java
private void parseJsonFeed(JSONObject response) {
try {
JSONObject parent = response.getJSONObject("response");
JSONArray feedArray = parent.getJSONArray("items");
for (int i = 0; i < feedArray.length(); i++) {
JSONObject feedObj = (JSONObject) feedArray.get(i);
FeedItem item = new FeedItem();
item.setId(feedObj.getInt("id"));
item.setName(feedObj.getString("post_type"));
item.setTimeStamp(feedObj.getString("date"));
// Image might be null sometimes
String image = feedObj.isNull("photo") ? null : feedObj
.getString("photo");
item.setImge(image);
item.setStatus(feedObj.getString("text"));
All code work till there how to get data from attachments
***JSONObject response1 = response.getJSONObject("response");
feedArray = parent.getJSONArray("items");***
JSONArray feedArray1 = response1.getJSONArray("attachments");
for (int i1 = 0; i1 < feedArray1.length(); i1++) {
JSONObject feedObj1 = (JSONObject) feedArray1.get(i1);
FeedItem item1 = new FeedItem();
item.setProfilePic(feedObj1.getString("photo_75"));
}
// url might be null sometimes
String feedUrl = feedObj.isNull("url") ? null : feedObj
.getString("url");
item.setUrl(feedUrl);
feedItems.add(item);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
Thanks in advance

you are looking for attachments in wrong object. "attachmetnts" is property of item.
instead of
JSONArray feedArray1 = response1.getJSONArray("attachments");
use
JSONArray feedArray1 = feedObj.getJSONArray("attachments");
in your case feedObj contains item object.
to get photo :
Remove lines :
String image = feedObj.isNull("photo") ? null : feedObj
.getString("photo");
item.setImge(image);
and change it to :
for (int i1 = 0; i1 < feedArray1.length(); i1++) {
JSONObject attachment = (JSONObject) feedArray1.get(i1);
JSONObject photo = (JSONObject) attachment.getJSONObject("photo");
item.setImge(photo);
item.setProfilePic(photo.getString("photo_75"));
item.setStatus(photo.getString("text"));
}

You can try GSON, which would directly give you a java object from your json and you would not have to parse it manually.

JSON parse Android - object in object

How to parse this json? I want get data from title, field_place and brothers fields.
{
"events": [
{
"event": {
"title": "BITUMIX Martyna Jastrz\u0119bska",
"field_place": "Nowe Miejsce Al Jerozolimskie 51 lok.2",
"field_zdjecie": "http:\/\/wybierzkulture.waw.pl\/sites\/default\/files\/styles\/post\/public\/martyna_jastrzebska_bitumix_2.jpg?itok=nd2O5U5z"
}
},
{
"event": {
"title": "Wiecz\u00f3r Komedii Improwizowanej - D\u017cem Impro!",
"field_place": "",
"field_zdjecie": "http:\/\/wybierzkulture.waw.pl\/sites\/default\/files\/styles\/post\/public\/dzem_17_maja.jpg?itok=bfgDYxKq"
}
},
...
I tried:
JSONObject itemm = jArray.getJSONObject(i);
JSONObject oneObject = itemm.getJSONObject("event");
String title = oneObject.getString("title");
String field_place = oneObject.getString("field_place");
... but it doesn't work.

In a JSON string , there are two symbols that guide you through parsing :
{ - indicates a JSONObject
[ - indicates a JSONArray
When parsing a json string, you should go through this items iteratively. To understand how many JsonObjects and JsonArrays you have in your string , and from which you should start parsing, use a json-visualizer tool like this website. :
Example : As you see, the root object is a JSONObject which consists of an JSONArray with three jsonOnjects. To parse such a structure you can use :
JSONObject jsonobj = new JSONObject(jsonstring);
String result = jsonObject.getString("success");
String error_number = jsonObject.getString("error_number");
String error_message = jsonObject.getString("error_message");
JSON Array jsonarray = jsonobj.getJSONArray();
String[] names = new String[jsonArray.length()];
String[] formattedNames = new String[jsonArray.length()];
for(int i=0;i<jsonArray.length();i++)
{
JSONObject jsonObject = jsonArray.getJSONObject(i);
names [i] = jsonObject.getString("name");
formattedNames [i] = jsonObject.getString("formattedName");
}

try this
JSONArray element = jsonobj.getJSONArray("events");
for(int i=0;i < element.length();i++){
JSONObject e = element.getJSONObject(i);
Log.d("TESTTT22",e.getJSONObject("event").getString("title"));
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}