You can customize a little bit of code like it

public static void main(String[] args) throws ParseException {
        String data = "{\"data\":[\"str1\", \"str2\", \"str3\"]}";
        JSONObject json = new JSONObject(
                data);
         
        JSONArray jasonArray = json.getJSONArray("data");
        List list = new ArrayList();

        int size = jasonArray.length();
        int i = 0;
        while (i < size) {
            list.add(jasonArray.get(i));
            i++;
        }

        System.out.println(list);

    }

Let us assume that the class is Data with two objects name and dob which are both strings.

Initially, check if the list is empty. Then, add the objects from the list to a JSONArray

JSONArray allDataArray = new JSONArray();
List<Data> sList = new ArrayList<String>();

    //if List not empty
    if (!(sList.size() ==0)) {

        //Loop index size()
        for(int index = 0; index < sList.size(); index++) {
            JSONObject eachData = new JSONObject();
            try {
                eachData.put("name", sList.get(index).getName());
                eachData.put("dob", sList.get(index).getDob());
            } catch (JSONException e) {
                e.printStackTrace();
            }
            allDataArray.put(eachData);
        }
    } else {
        //Do something when sList is empty
    }
    

Finally, add the JSONArray to a JSONObject.

JSONObject root = new JSONObject();
    try {
        root.put("data", allDataArray);
    } catch (JSONException e) {
        e.printStackTrace();
    }

You can further get this data as a String too.

String jsonString = root.toString();

You can use JSONArray to get value from key 'name'. Like this:

JSONArray jSONArray = new JSONArray(yourJson);
List<String> list = new ArrayList<>();
for (int i = 0; i < jSONArray.length(); i++) {
  JSONObject object = (JSONObject) jSONArray.get(i);
  String value = object.getString("name");
  System.out.println(value);
  list.add(value);
}