CODEWITHSUNDEEP
javajson
AppleBud
AppleBud

Reputation: 1541

How can i sort my JSON object based on Key?

I am creating a JSON object in which i am adding a key and a value which is an array. The value for both key and value comes from a TreeSet which has data in sorted form. However, when I insert data in my json object, it is stored randomly without any order. This is my json object currently:

{
    "SPAIN":["SPAIN","this"],
    "TAIWAN":["TAIWAN","this"],
    "NORWAY":["NORWAY","this"],
    "LATIN_AMERICA":["LATIN_AMERICA","this"]
}

and my code is:

 Iterator<String> it= MyTreeSet.iterator();

        while (it.hasNext()) {
            String country = it.next();
            System.out.println("----country"+country);
            JSONArray jsonArray = new JSONArray();
            jsonArray.put(country);
            jsonArray.put("this);

            jsonObj.put(country, jsonArray);
        }

Is there any way I can store the data into my json object inside the while loop itself?

Upvotes: 5

Views: 33244

Answers (3)

Christian
Christian

Reputation: 4641

Even if this post is quite old, I thought it is worth posting an alternative without GSON:

First store your keys in an ArrayList, then sort it and loop through the ArrayList of keys:

Iterator<String> it= MyTreeSet.iterator();
ArrayList<String>keys = new ArrayList();

while (it.hasNext()) {
    keys.add(it.next());
}
Collections.sort(keys);
for (int i = 0; i < keys.size(); i++) {
    String country = keys.get(i);
    System.out.println("----country"+country);
    JSONArray jsonArray = new JSONArray();
    jsonArray.put(country);
    jsonArray.put("this");

    jsonObj.put(country, jsonArray);
}

Upvotes: 10

deepSleep
deepSleep

Reputation: 47

Below are what the doc says from http://www.json.org/java/index.html.

"A JSONObject is an unordered collection of name/value pairs."

"A JSONArray is an ordered sequence of values. "

In order to get an sorted Json Object, you can use Gson which is already provided a good answer by @user748316.

Upvotes: 1

user748316
user748316

Reputation: 348

It works with Google Gson API. Try it out. 

    try{

        TreeSet<String> MyTreeSet = new TreeSet<String>();
        MyTreeSet.add("SPAIN");
        MyTreeSet.add("TAIWNA");
        MyTreeSet.add("INDIA");
        MyTreeSet.add("JAPAN");

        System.out.println(MyTreeSet);
        Iterator<String> it= MyTreeSet.iterator();
        JsonObject gsonObj = new JsonObject();
        JSONObject jsonObj = new JSONObject();
        while (it.hasNext()) {
            String country = it.next();
            System.out.println("----country"+country);
            JSONArray jsonArray = new JSONArray();
            jsonArray.put(country);
            jsonArray.put("this");

            jsonObj.put(country, jsonArray);

            JsonArray gsonArray = new JsonArray();

            gsonArray.add(new JsonPrimitive("country"));
            gsonArray.add(new JsonPrimitive("this"));
            gsonObj.add(country, gsonArray);
        }
        System.out.println(gsonObj.toString());
        System.out.println(jsonObj.toString());




    } catch (JSONException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

Upvotes: 2

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