Add 2 json objects according to keys in java

Question

I am working on Json Objects in java!. I have 2 json objects as follows:

{"a":{"num1":5},"b":{"num1":8}}

{"a":{"num2":7},"b":{"num2":9}}

I want to create a single json object as:

 {"a":{"num1":5,"num2":7},"b":{"num1":8,"num2":9}}

How should i merge the 2 objects to achieve the above result?

Answer 1

The easy way is to create list and loop over two Objects:

public static void main(String[] args) {
    String str1 = "{\"a\":{\"num1\":5},\"b\":{\"num1\":8}}";
    String str2 = "{\"a\":{\"num2\":7},\"b\":{\"num2\":9}}";

    try {
        JSONObject str1Json  = new JSONObject(str1);
        JSONObject str2Json  = new JSONObject(str2);

        List<JSONObject> list = Arrays.asList(str1Json, str2Json);

        JSONObject storage = new JSONObject();
        JSONObject storageA = new JSONObject();
        JSONObject storageB = new JSONObject();
        JSONObject a;
        JSONObject b; 
        JSONObject obj;

        for(int i=1; i<= list.size(); i++){

            obj  = list.get(i-1);

            a = obj.getJSONObject("a");
            b = obj.getJSONObject("b");

            storageA.put("num"+i, a.getInt("num"+i)); // we don't want build list               
            storageB.put("num"+i, b.getInt("num"+i));               
        }

        storage.put("a", storageA);
        storage.put("b", storageB);

        System.out.println(storage.toString());
    } catch (JSONException e1) {
    }
} 

Output:

 {"b":{"num2":9,"num1":8},"a":{"num2":7,"num1":5}}