Develop Reference

Getting a JSON Array from JSON Object (SOLVED)

First time having to work with JSON data on my own, even if very simple.
Here is the JSON data I'm working with:
{
"heart" : [92, 108],
"temperature" : [85.08, 85.66],
"conductance" : [4095, 4095]
}
What I'm attempting to do is extract one of the three arrays found within that JSON object, but I'm receiving a JSONException: Not a primitive array: class org.json.JSONArray. Here is a portion of the code that I'm using to extract the array of values associated with "heart":
JSONObject obj = new JSONObject(obtainJSONObject());
JSONArray arr = new JSONArray(obj.getJSONArray("heart")); // This is where the error is occuring
int low = arr.getInt(0);
int high = arr.getInt(1);
I've tried to follow what this solution answered, but can't really make much sense of it: How to Get JSON Array Within JSON Object?
I'm not sure if it has something to do with the way how the JSON data is being formatted? I did check online to see if it was any valid or not at https://jsonformatter.curiousconcept.com/. Any help or insights will be greatly appreciated!

how to know if a json object contains a json object

I am a novice in java and I am looking for a way to know if a json object contains another jsonObject by using json.org library (not json.org.simple).
For the moment I am using this :
JSONObject json= new JSONObject();
json.has("JsonFieldName");
but but I need to know if there is a way to not specify the Json field Name
If you have a better solution with Json.org, I will take.
Thanks

You can get an Iterator for all the keys in the object from keys, and loop through them seeing if any of the values for the keys is a JSONObject (as opposed to a JSONArray or primitive).
for (String key : json.keys()) {
if (json.get(key) instanceof JSONObject) {
// Yes, it contains at least one JSONObject, whose key is `key`
}
}

How to parse a jsonObject or Array in Java

I have an API request from my CRM that can either return a jsonObject if there is only one result, or a jsonArray if there are multiple results. Here are what they look like in JSON Viewer
JsonObject:
JsonArray:
Before you answer, this is not my design, it's my CRM's design, I don't have any control over it, and yes, I don't like how it is designed either. The only reason I am not storing the records in my own database and just parsing that, which would be MUCH easier, is because my account is having issues not running some workflows that would allow me to auto add the records. Is there any way to figure out if the result is an object or an array using java? This is for an android app by the way, I need it to display the records on the phone.

You should use OPT command instead of GET
JSONObject potentialObject=response.getJsonObject("resuslt")
.getJsonObject("Potentials");
// here use opt. if the object is null, it means its not the type you specified
JSONObject row=potentialObject.optJsonObject("row");
if(row==null){
// row is json array .
JSONArray rowArray=potentialObject.getJsonArray("row");
// do whatever you like with rowArray
} else {
// row is json object. do whatever you like with it
}

ONE
You can use instanceof keyword to check the instances as in
if(json instanceof JSONObject){
System.out.println("object");
}else
System.out.println("array");
TWO
BUT I think a better way to do this is choose to use only JSONArray so that the format of your results can be predicated and catered for. JSONArrays can contain JSONObjects. That is they can cover the scope of JSONObject.
For example when you get the response (either in a JSONObject or a JSONArray), you need to store that in an instance. What instance are you going to store it in? So to avoid issues use JSONArray to store the response and provide statements to handle that.
THREE
Also you can try method overloading in java or Generics

Simplest way is to use Moshi, so that you dont have to parse, even in the case of the Model changing later, you have to change your pojo and it will work.
Here is the snippet from readme
String json = ...;
Moshi moshi = new Moshi.Builder().build();
JsonAdapter<BlackjackHand> jsonAdapter = moshi.adapter(BlackjackHand.class);
BlackjackHand blackjackHand = jsonAdapter.fromJson(json);
System.out.println(blackjackHand);
https://github.com/square/moshi/blob/master/README.md

Detect type of JSON attribute

JSON:
{"attribute1":11, "attribute2":"string atribute"}
I want to detect what kind of type are attribute1 and attribute2:
attribute1 is integer
attribute2 is string
jsonObject.getAttributeType("attribute2"); // should output: string/integer/boolean.
It was very easy to achieve in PHP or OBJC. Suggestions?

(I'm assuming that the Android for the org.json package is that same as you can find on the json.org site ... here.)
The only method on a JSONObject that will give you the underlying value ... without coercing it ... is JSONObject.get(name). If name is known, the result is the object that represents the value internally. I haven't done a comprehensive trawl of the code, but I think it can only be one of the following types:
Boolean, Long, Double, String, JSONArray, JSONObject
You should be able to discriminate these using instanceof.
But should be asking yourself if this is the right thing to do. The normal way to deal with JSON object attributes via the JSONObject API is to use the methods that coerce them into the type that you expect. In most cases, it doesn't matter if a number is sent as 42 or 42.0 or "42" ... and it is best not to be picky if the intent is easy to determine.

Another solution you can use the jackson library to do this,
import com.fasterxml.jackson.databind.JsonNode;
import com.github.fge.jackson.JsonLoader;
//Defining the JSON object
JSON json = {"attribute1":11, "attribute2":"string atribute"};
//Get the needed attribute
String value = json.get("attribute1");
//Convert the attribute to JsonNode
JsonNode value = JsonLoader.fromString(value);
//Then you can check type as below
value.isObject();
value.isArray();
value.isDouble();
value.isTextual();
value.isInt()

JSON Parsing problem

Hey,
Im trying to parse the following JSON data:
{"chat":
{"link":
[{"#rel":"next","#ref":"http"}],
"events":
{"link2":
[{"#rel":"next","#ref":"http"}]}
}}
The code that reads the data is (where 'a' is the JSON as String):
JSONObject jsonObject1 = new JSONObject(a);
JSONObject jsonObject = jsonObject1.getJSONObject("chat");
So the structure (at least the way I intended) is:
<chat>
<link>
<events>
<link2>
</events>
</chat<
But, after getJsonObject("chat"), jsonObject equals to:
{"chat":{"events":{"link2":[{"#ref":"http","#rel":"next"}]},"link":[{"#ref":"http","#rel":"next"}]}}
What am I missing? Why does the data flips and the structure changes?

The properties in a JSON object are not sorted. From the JSON site:
An object is an unordered set of name/value pairs...
(My emphasis) Therefore the position of link and event are irrelevant for the parser. Bottom line, link and event are at the same level therefore they can be shifted and wherever order matters use arrays in JSON ... [].