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Update Json value in json Array in Java

{
"page": {
"size": 2,
"number": 2
},
"places": [
{
"eventName": "XYZ",
"createdByUser": "xyz#xyz.com",
"modifiedDateTime": "2021-03-31T09:59:48.616Z",
"modifiedByUser": "xyz#xyz.com"
}
]}
I am trying to update the "eventName" field with new String. I tried with the following code, It updates the field but returns only four fields in the json array.
public String modifyJson() throws Exception{
String jsonString = PiplineJson.payload(PiplineJson.filePath());
System.out.println(jsonString);
JSONObject jobject = new JSONObject(jsonString);
String uu = jobject.getJSONArray("places")
.getJSONObject(0)
.put("eventName", randomString())
.toString();
System.out.println(uu);
return uu;
}
This is what the above code does.
{
"eventName": "ABCD",
"createdByUser": "xyz#xyz.com",
"modifiedDateTime": "2021-03-31T09:59:48.616Z",
"modifiedByUser": "xyz#xyz.com"
}
I am trying to get the complete json once it updates the eventName filed.
{
"page": {
"size": 2,
"number": 2
},
"places": [
{
"eventName": "ABCD",
"createdByUser": "xyz#xyz.com",
"modifiedDateTime": "2021-03-31T09:59:48.616Z",
"modifiedByUser": "xyz#xyz.com"
}
]}

The problem is the way that you are chaining the operations together. The problem is that you are calling toString() on the result of the put call. The put calls returns the inner JSONObject that it was called on. So you end up serializing the wrong object.
Changing this:
String uu = jobject.getJSONArray("places")
.getJSONObject(0)
.put("eventName", randomString())
.toString();
to
jobject.getJSONArray("places")
.getJSONObject(0)
.put("eventName", randomString());
String uu = jobject.toString();
should work.

That's because you are returning the first element you extracted from "places" array. You should return "jobject.toString()" instead.

Deserialize complex json body, validate one element in it, then through that, map to another element (JAVA) is it possible?

I have a json array to work with, like so:
[
{
"id": "12345",
"eauthId": "123451234512345123451234512345",
"firstName": "Jane",
"middieInitial": "M",
"lastName": "Doe",
"email": "janedoe#usda.gov",
"roles": [
{
"id": "CTIS_ROLE_ID",
"name": "A test role for CTIS",
"treatmentName": "Fumigation"
}
]
},
{
"id": "67890",
"eauthId": "678906789067890678906789067890",
"firstName": "John",
"middieInitial": "Q",
"lastName": "Admin",
"email": "johnadmin#usda.gov",
"roles": [
{
"id": "CTIS_ADMIN",
"name": "An admin role for CTIS",
"treatmentName": "System Administration"
}
]
}
]
My task is to find out the user's "roles" --> "name", once match, get that user's email address and sign in using that email address. It seems like a simple task, but it has been really kicking my bottom, since digging into API is new to me. I've tried different libraries (Jackson, RestAssured, Json Simple) and finally GSon. I don't have time to sit and study everything from the scratch. I just needed a quick solution. But it definitely hasn't been quick. Is anyone kind enough to help me out with this. I'd really appreciate it.
closeableHttpResponse = restClient.get(ConfigurationReader.get("base_url") + ConfigurationReader.get("user_endpoint"));
//Status code
int statusCode = closeableHttpResponse.getStatusLine().getStatusCode();
System.out.println("statusCode = " + statusCode);
String responseString = EntityUtils.toString(closeableHttpResponse.getEntity(), "UTF-8");
Type userListType = new TypeToken<List<Users>>(){}.getType();
List<Users> users = (List<Users>) new Gson().fromJson(responseString, userListType);
Roles roles = new Gson().fromJson(responseString, Roles.class);
it gives me this error
com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at line 1 column 2 path $
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:226)
at com.google.gson.Gson.fromJson(Gson.java:932)

The problem with your code is
Type userListType = new TypeToken<List>(){}.getType();
List users = (List) new Gson().fromJson(responseString, userListType);
You are not receiving just a list, you are actually deserializing an array of lists.
So try this:
List[] users = (List[]) new Gson().fromJson(responseString, List[].class);

Why do I always get JSON Exception?

This Is my first time with parsing JSON data. I am using the Google knowledge graph api. I got the api working and I can get the JSON result. This is Google 's sample return data for a sample query which I'm using now for testing.
{
"#context": {
"#vocab": "http://schema.org/",
"goog": "http://schema.googleapis.com/",
"resultScore": "goog:resultScore",
"detailedDescription": "goog:detailedDescription",
"EntitySearchResult": "goog:EntitySearchResult",
"kg": "http://g.co/kg"
},
"#type": "ItemList",
"itemListElement": [
{
"#type": "EntitySearchResult",
"result": {
"#id": "kg:/m/0dl567",
"name": "Taylor Swift",
"#type": [
"Thing",
"Person"
],
"description": "Singer-songwriter",
"image": {
"contentUrl": "https://t1.gstatic.com/images?q=tbn:ANd9GcQmVDAhjhWnN2OWys2ZMO3PGAhupp5tN2LwF_BJmiHgi19hf8Ku",
"url": "https://en.wikipedia.org/wiki/Taylor_Swift",
"license": "http://creativecommons.org/licenses/by-sa/2.0"
},
"detailedDescription": {
"articleBody": "Taylor Alison Swift is an American singer-songwriter and actress. Raised in Wyomissing, Pennsylvania, she moved to Nashville, Tennessee, at the age of 14 to pursue a career in country music. ",
"url": "http://en.wikipedia.org/wiki/Taylor_Swift",
"license": "https://en.wikipedia.org/wiki/Wikipedia:Text_of_Creative_Commons_Attribution-ShareAlike_3.0_Unported_License"
},
"url": "http://taylorswift.com/"
},
"resultScore": 896.576599
}
]
}
So I want to parse it so that I can get the name, description, detailed description. This is my code but I always seem to get the exception. Any ideas why?
try {
JSONObject object=new JSONObject(gggg);
JSONArray itemListElement = object.getJSONArray("itemListElement");
for(int i=0; i < itemListElement.length();i++){
JSONObject c = itemListElement.getJSONObject(i);
JSONObject results = c.getJSONObject("result");
String name = results.getString("name").toString();
String description = results.getString("description").toString();
String detailedDescription = results.getString("articleBody").toString();
gggg = "Name: "+name+"\n Description: "+description+"\n "+detailedDescription;
}
responseView.append(gggg);
} catch (JSONException e) {
Toast.makeText(MainActivity.this,gggg,Toast.LENGTH_LONG).show();
}
Also the string gggg contains the JSON data. I don't know why but I am always getting the exception. Please tell me what is the error in my code and how to repair it.
Thanks.

"Name: Taylor Swift Description: Singer-songwriter Taylor Alison
Swift is an American singer-songwriter and actress. Raised in
Wyomissing, Pennsylvania, she moved to Nashville, Tennessee, at the
age of 14 to pursue a career in country music. "
The problem is your String detailedDescription line.
You need to get the detailedDescription object before you retrieve the articleBody.
for(int i=0; i < itemListElement.length();i++){
JSONObject c = itemListElement.getJSONObject(i);
JSONObject results = c.getJSONObject("result");
String name = results.getString("name");
String description = results.getString("description");
JSONObject detailedDescription = results.getJSONObject("detailedDescription");
String articleBody = detailedDescription.getString("articleBody");
String x = "Name: "+name+"\n Description: "+description+"\n "+articleBody;
}
Also your .toString() method calls are redundant as you are calling .getString() on the JSON object.

With in the android json library it has a method called has element, which returns true or false. After successfully checking then access the element. The expection be caused by tring to access an element that isn't there.
Might be worth printing out after each time you create a new object to ensure that the objects are being created. It will also piont to where the expection is happening.

Java - How to get object value in JSON array?

i have a JSON like example below and i'm trying to get some values, for example value of.
results.shipper.id
{
"results": [
{
"updated": false,
"notification": false,
"some_data": {
"id": 15989,
"pieces": 0,
},
"shipper": {
"updated": false,
"notification": false,
"id": 1587,
"parent": {
"updated": false
},
I'm trying to get value by this way:
String test = shipmentData.getJSONObject("shipper").getString("id");
But it always throws a exception. I think, that exception is caused because of the i am not accessing to the values via "results" array.
How can i easy access to the value what i need.
I tried find some helpers (Gson, fast-json, etc..) but it seems to be a quite complicated for using (i would like to work with JSON tree for direct access to values "on-the-fly" or access to values like to a object, it means.. Object.InnerObject.value ).
So question is how can i do it right?
Thanks for any advice.

JSON needs to be traversed in order to access id:
JSONArray results = shipmentData.getJSONArray("results");
JSONObject first = results.getJSONObject(0);
JSONObject shipper = first.getJSONObject("shipper");
Integer id = shipper.getInt("id");
Parse int to string:
String id = String.valueOf(shipper.getInt("id"));

Different JSON array response

I have problems parsing two different JSON responses.
1: This is the JSON response I get from a RESTful API:
{
"gear": [
{
"idGear": "1",
"name": "Nosilec za kolesa",
"year": "2005",
"price": "777.0"
}, {
"idGear": "2",
"name": "Stresni nosilci",
"year": "1983",
"price": "40.0"
}
]
}
2: This response I get from my testing client. I was added some values to the list and then I used gson.toJson for testing output.
[
{
"idGear": "1",
"name": "lala",
"year": 2000,
"price": 15.0
}, {
"idGear": "2",
"name": "lala2",
"year": 2000,
"price": 125.0
}
]
They are both valid, but the second one was successfully deserialize to object like this:
Type listType = new TypeToken<List<Gear>>() {}.getType();
List<Gear> gears= (List<Gear>) gson.fromJson(json, listType);
With the first one, I was trying to deserialize the same way but I get error.
EDIT
API Method:
#GET
#Produces(MediaType.APPLICATION_JSON)
public List<Gear> getGear() {
List<Gear> gears = gearDAO.getGears();
if (!gears.isEmpty()) {
return gears;
} else
throw new RuntimeException("No gears");
}
CLIENT serialization code:
List<Gear> list = new ArrayList<Gear>();
Gear o = new Gear();
o.setPrice(15);
o.setYear(2000);
o.setName("asds");
Type listTypes = new TypeToken<List<Gear>>() {}.getType();
gson.toJson(list, listTypes);

The JSON responses are different!
The first one is an object, surrounded by { }, which contains a field "gear" that is in turn a list of objects, surrounded by [ ].
The second one is directly a list of objects, because it's surrounded by [ ]. Namely, the whole 2nd response is equivalent to the field in the 1st response.
So, obviously they can't be parsed in the same way...
The 2nd one is being parsed correctly because you are using a List and it is a list. But for the 1st one you need another class that contains a field that contains in turn a list... That is, you just need to create a class structure that represents your JSON responses...
public class Response {
private List<Gear> gears;
//getters & setters
}
Now you can parse your 1st response with:
Gson gson = new Gson();
Response response = gson.fromJson(json, Response .class);
List<Gear> gears = response.getGears();
I suggest you to take a brief look at json.org in order to understand JSON syntax, which is pretty simple...
Basically these are the possible JSON elements:
object
{}
{ members }
members
pair
pair , members
pair
string : value
array
[]
[ elements ]
elements
value
value , elements
value
string
number
object
array
true
false
null