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Read a specific value from JSON in Java

I am making an app in android studio using an API that returns the following:
[{"domains": ["upes.ac.in"], "country": "India", "state-province": "Dehradun", "web_pages": ["https://www.upes.ac.in/"], "name": "University of Petroleum and Energy Studies", "alpha_two_code": "IN"}]
I run it as follows:
public void onResponse(String response) {
listaUniversidades = new ArrayList<>();
JSONArray jsonArray = new JSONArray(response);
String nombreUni, pais, url;
for (int i = 0; i < jsonArray.length(); i++) {
nombreUni = jsonArray.getJSONObject(i).getString("name");
pais = jsonArray.getJSONObject(i).getString("country");
url = jsonArray.getJSONObject(i).getString("web_pages"));
texto.setText(url);
listaUniversidades.add(new Universidad(nombreUni, pais, url));
}}
The thing is that the web_pages returns the following: ["http://.www.upes.ac.in/"]
How could I make it return the correct url? Since that way I can not access the university website.
Thank you!

I will assume that you aways want to get the first "web_page" inside the "web_pages" array.
You can try to convert the "web_pages" attribute to an array before trying to get the first element, like this:
url = jsonArray
.getJSONObject(i)
.getJSONArray("web_pages"))
.getJSONObject(0)
.toString();

Have you verified that the API returns the expected value for web_pages? You can set a breakpoint on the line
String nombreUni, pais, url;
And then inspect the variable jsonArray. I think the incorrect value that you got is most likely because the API returns that value.

The problem is that "web_pages": ["https://www.upes.ac.in/"] is a JSON Array, so you need to convert it to the array and then access the appropriate item in it(presumably first one?)
It can be done the way Aleph proposed above.

Trouble with getting strings into JSON

My servlet recieves/loads multiple parameters from/for an article (price, id, count, name).
While they are saved in the session for other purposes I want to display them in a Shopping cart.
So my idea was to get all values into a json like this
{"id":1, "prductName":"article1"}
but my json always ends up empty.
I had two approaches:
String prname = request.getParameter("name");
String anz = String.valueOf(session.getAttribute("Anzahl"));
String prid = request.getParameter("id");
String price = request.getParameter("price");
These are my parameters:
First try:
class ToJson{
String prname1 = String.valueOf(session.getAttribute("prname"));
String anz1 = String.valueOf(session.getAttribute("Anzahl"));
String prid1 = String.valueOf(session.getAttribute("id"));
String price1 = String.valueOf(session.getAttribute("price"));
}
ToJson obj = new ToJson();
Jsonb jsonb = JsonbBuilder.create();
String jsn1 = jsonb.toJson(obj);
Ends up with: {}
Second try:
ArrayList<String> ar = new ArrayList<String>();
ar.add(prname);
ar.add(price);
ar.add(prid);
ar.add(anz);
ToJson obj = new ToJson();
Jsonb jsonb = JsonbBuilder.create();
String jsn = jsonb.toJson(ar);
Ends up with: ["P1neu","25","1","145"]
It isn't in a format I wanted and I also don't know how to access the seperate values here, I tried jsn[1] but it didnt work.
Could you help me, please?

To your first question, why JSON object is printing empty:
You are missing getters & setters in the ToJSON class for JSON Builder/Parser to access the properties/fields, and that's why its printing as empty object.
To your second question, how do I access JSON properties:
JSON representation is a natively a string representation, and you can't read part of string as jsn[1].
For reading JSON object properties, you convert it into POJO using available any of preferred open source parser libraries like Jacksons, Gson etc. And then access POJO properties using standard java getter/setters.

Parsing JSON in Java Using org.json

I have a large file with many JSON objects similiar to the following. I need to parse everything to get the "bought_together" items as an array using the org.json library. I'm having trouble accessing anything nested in "related".
What is the required code to retrieve "bought_together" as a list?
{
"asin": "11158732",
"title": "Girls Ballet Tutu Zebra Hot Pink",
"price": 3.17,
"imUrl": "http://ecx.images-amazon.com/images/I/51fAmVkTbyL._SY300_.jpg",
"related":
{
"also_bought": ["L00JHONN1S", "B002BZX8Z6"],
"also_viewed": ["F002BZX8Z6", "B00JHONN1S", "B008F0SU0Y", "B00D23MC6W", "B00AFDOPDA"],
"bought_together": ["D202BZX8Z6"]
},
"salesRank": {"Toys & Games": 211836},
"brand": "Coxlures",
"categories": [["Sports & Outdoors", "Other Sports", "Dance"]]
}
Here is my attempt (Please note, this is within a MapReduce program so some lines may seem out of context.):
JSONObject object = new JSONObject(sampleText); //sampleText is json that has been split by line
JSONArray boughtTogether = new JSONArray(object.getJSONArray("bought_together"));

using the following code, I hope it's help you.
//this will be your json object that contains and convert your string to jsonobject
//if you have json object already skip this.
JSONObject yourJSON = new JSONObject(targetString);
//getting the "related" jsonObject
JSONObject related = yourJSON.getJSONObject("related");
//getting the "bought_together" as an jsonArray and do what you want with it.
//you can act with jsonarray like an array
JSONArray bought_together = related.getJSONArray("bought_together");
//now if you run blow code
System.out.print(bought_together.getString(0));
//output is : D202BZX8Z6
-------update according to update the question------
you should change your code like this:
JSONObject object = new JSONObject(sampleText); //sampleText is json that has been split by line
JSONObject related = object.getJSONObject("related");
JSONArray boughtTogether = related.getJSONArray("bought_together");
-------update-------
i think you need to this point (it's not technicality all of they difference)
every thing are in {} , they will be JSONObject and the relation
is key and value like :
{"name":"ali"}
this is a jsonobject and the value of key "name" is ali and we call it
like:
myJsonObject.getString("name");
every thing are in [] ,they will be JSONArray and the relation is
index and value like :
["ali"]
this is a JsonArray the value of index 0 is ali and we call it
like:
myJsonArray.getString(0);
so in your case:
your total object is a JSONObject
the value of "related" key is still a JSONObject
the value of "bought_together" key (which is inside the value of {jsonobject} "related" key) is a JSONArray

Jettison JSON/java , send list of string with json request

I am creating JSON object and send over the network , like
org.codehaus.jettison.json.JSONObject json = new org.codehaus.jettison.json.JSONObject();
json.put("id", "15");
json.put("code", "secret");
json.put("type", "new type");
Also I have links of photos what I want to put into this JSON
my links like http://box.com/images/photo.jpg,http://box.com/images/photo1.jpg
http://box.com/images/photo2.jpg, http://box.com/images/photo3.jpg
As I understand I must have some list/array and put like
json.put("images", links)
How to do it, put and parse... I need one key, and list of values.
Is JSON array is useful for this?
Thanks

Yes. JSONArray is what you need.
List <String> links = getLinks();
JSONArray array = new JSONArray();
for (String link : links)
array.put(link);
JSONObject obj = new JSONObject();
//put id, code, type...
obj.put("images", array);

Check out the JSONArray class.
http://jettison.codehaus.org/apidocs/org/codehaus/jettison/json/JSONArray.html
You'll create a JSONArray and use that in your put command.

JSONObject in JSONObject

I have an API Output like this:
{"user" : {"status" : {"stat1" : "54", "stats2" : "87"}}}
I create a simple JSONObject from this API with:
JSONObject json = getJSONfromURL(URL);
After this I can read the data for User like this:
String user = json.getString("user");
But how do I get the Data for stat1 and stat2?

JSONObject provides accessors for a number of different data types, including nested JSONObjects and JSONArrays, using JSONObject.getJSONObject(String), JSONObject.getJSONArray(String).
Given your JSON, you'd need to do something like this:
JSONObject json = getJSONfromURL(URL);
JSONObject user = json.getJSONObject("user");
JSONObject status = user.getJSONObject("status");
int stat1 = status.getInt("stat1");
Note the lack of error handling here: for instance the code assumes the existence of the nested members - you should check for null - and there's no Exception handling.

JSONObject mJsonObject = new JSONObject(response);
JSONObject userJObject = mJsonObject.getJSONObject("user");
JSONObject statusJObject = userJObject.getJSONObject("status");
String stat1 = statusJObject.getInt("stat1");
String stats2 = statusJObject.getInt("stats2");
from your response user and status is Object so for that use getJSONObject and stat1 and stats2 is status object key so for that use getInt() method for getting integer value and use getString() method for getting String value.

To access properties in an JSON you can parse the object using JSON.parse and then acceess the required property like:
var star1 = user.stat1;

Using Google Gson Library...
Google Gson is a simple Java-based library to serialize Java objects to JSON and vice versa. It is an open-source library developed by Google.
// Here I'm getting a status object inside a user object. Because We need two fields in user object itself.
JsonObject statusObject= tireJsonObject.getAsJsonObject("user").getAsJsonObject("status");
// Just checking whether status Object has stat1 or not And Also Handling NullPointerException.
String stat1= statusObject.has("stat1") && !statusObject.get("stat1").isJsonNull() ? statusObject.get("stat1").getAsString(): "";
//
String stat2= statusObject.has("stat2") && !statusObject.get("stat2").isJsonNull() ? statusObject.get("stat2").getAsString(): "";
If You have any doubts , Please let me know in comments ...