json array java example

How to create correct JSONArray in Java using JSONObject

stackoverflow.com › questions › 18983185 › how-to-create-correct-jsonarray-in-java-using-jsonobject

Here is some code using java 6 to get you started:

JSONObject jo = new JSONObject();
jo.put("firstName", "John");
jo.put("lastName", "Doe");

JSONArray ja = new JSONArray();
ja.put(jo);

JSONObject mainObj = new JSONObject();
mainObj.put("employees", ja);

Edit: Since there has been a lot of confusion about put vs add here I will attempt to explain the difference. In java 6 org.json.JSONArray contains the put method and in java 7 javax.json contains the add method.

An example of this using the builder pattern in java 7 looks something like this:

JsonObject jo = Json.createObjectBuilder()
  .add("employees", Json.createArrayBuilder()
    .add(Json.createObjectBuilder()
      .add("firstName", "John")
      .add("lastName", "Doe")))
  .build();

Answer from Grammin on Stack Overflow

Stack Overflow

stackoverflow.com › questions › 18983185 › how-to-create-correct-jsonarray-in-java-using-jsonobject

json - How to create correct JSONArray in Java using JSONObject - Stack Overflow

Top answer

1 of 4

282

Here is some code using java 6 to get you started:

JSONObject jo = new JSONObject();
jo.put("firstName", "John");
jo.put("lastName", "Doe");

JSONArray ja = new JSONArray();
ja.put(jo);

JSONObject mainObj = new JSONObject();
mainObj.put("employees", ja);

Edit: Since there has been a lot of confusion about put vs add here I will attempt to explain the difference. In java 6 org.json.JSONArray contains the put method and in java 7 javax.json contains the add method.

An example of this using the builder pattern in java 7 looks something like this:

JsonObject jo = Json.createObjectBuilder()
  .add("employees", Json.createArrayBuilder()
    .add(Json.createObjectBuilder()
      .add("firstName", "John")
      .add("lastName", "Doe")))
  .build();

2 of 4

18

I suppose you're getting this JSON from a server or a file, and you want to create a JSONArray object out of it.

String strJSON = ""; // your string goes here
JSONArray jArray = (JSONArray) new JSONTokener(strJSON).nextValue();
// once you get the array, you may check items like
JSONOBject jObject = jArray.getJSONObject(0);

Hope this helps :)

Oracle

docs.oracle.com › javaee › 7 › api › javax › json › JsonArray.html

JsonArray (Java(TM) EE 7 Specification APIs)

If the value at the specified position is JsonValue.TRUE this method returns true. If the value at the specified position is JsonValue.FALSE this method returns false. Otherwise this method returns the specified default value. ... Returns true if the value at the specified location in this array is JsonValue.NULL.

Discussions

How to turn json objects into an array of json objects using Java?

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r/javahelp

7

4

June 28, 2022

New to Java, wanted some help with reading .json object arrays.

it gives me an error What's the error? More on reddit.com

r/javahelp

11

1

January 16, 2024

using JSONArray, JSONObject etc. to parse JSON with Java

I'd highly advise you to use the ObjectMapper instead of JSONArray and JSONObject. Try to mimic the json objects structure with a class, create 0 field and all argument contrstructors, getters and setters and simply use new ObjectMapper().readValue(yourJsonString, YouMappedObject.class) More on reddit.com

r/javahelp

6

5

December 4, 2021

How to parse Json array with 2 or more different types using Jackson?

http://www.baeldung.com/jackson-inheritance

You'll need to have those types inherit from one base class though.

Also; that is really bad JSON.

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