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I'm exporting some data in java using JSON then I'm reading that data and trying to get elements from an array inside the JSON object but I'm having issues.

I have tried a lot of things like 

jsonObject.get("InGameCord").get("x")
Object Testo = jsonObject.get("InGameCord");
Testo.x

Things like that along with more that did not work so deleted the code.

This is the exported JSON file and im trying to access the InGameCord array X or Y. 

{"BaseID":1,"BaseName":"Bandar-e-Jask Airbase","InGameCord":[{"x":463,"y":451}]}

Here is my file reader code

FileReader reader = new FileReader(filename);
JSONParser jsonParser = new JSONParser();
JSONObject jsonObject = (JSONObject) jsonParser.parse(reader);
System.out.println(jsonObject);
System.out.println("BaseName: "+jsonObject.get("BaseName"));
System.out.println("BaseID: "+jsonObject.get("BaseID"));
System.out.println("InGameCord: "+jsonObject.get("InGameCord"));

All of this works and exports the correct info.

So I'm trying to get let us say the X value of InGameCord.

int X = 463;
Paramjit Singh Rana
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A Hamburgler
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  • Where are you getting **JSON**Object and **JSON**Parser from? I ask because the Java EE 8 specification uses different case for the interface names: `javax.json.JsonObject` and `javax.json.stream.JsonParser`. – skomisa Mar 28 '19 at 05:44
  • ```import org.json.simple.JSONArray; import org.json.simple.JSONObject; import org.json.simple.parser.JSONParser;``` – A Hamburgler Mar 28 '19 at 14:26

1 Answers1

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Given your JSON data {"BaseID":1,"BaseName":"Bandar-e-Jask Airbase","InGameCord":[{"x":463,"y":451}]}:

  • "InGameCord" is the name of an array which can be instantiated as a JSONArray.
  • That array contains only one element: {"x":463,"y":451}.

  • That array element can be instantiated as a JSONObject. It contains two name/value pairs:

    • "x" with the value 463.
    • "y" with the value 451.

So based on the code you provided, to instantiate the JSONArray:

JSONArray numbers = (JSONArray) jsonObject.get("InGameCord");

To retrieve the first (and only) element of the array into a JSONObject:

JSONObject jObj = (JSONObject) numbers.get(0);

To get the value for "x" into an int variable cast the Object returned by get() to a Number, and then get its intValue():

int value = ((Number) jObj.get("x")).intValue();

You can even do the whole thing in one line, but it's ugly:

int y = ((Number) ((JSONObject) numbers.get(0)).get("y")).intValue();

skomisa
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