Android – create nested JSON objects

I tried to create a complex nested object as follows:

{
   "user":{
      "type":"facebook",
      "first_name":"harsha",
      "last_name":"mv",
      "gender":"male"
   },
   "friends":[
      {
         "id":"23",
         "name":"Vachana"
      },
      {
         "id":"23",
         "name":"Jyosna"
      },
      {
         "id":"23",
         "name":"Avinash"
      }
   ]
}

Android java code:

    JSONObject user = new JSONObject();
    try {
        user.put("first_name", "harsha");
        user.put("last_name", "mv");
        user.put("gender", "mail");

        System.out.println(user);
    } catch (JSONException e1) {
        e1.printStackTrace();
    }

I want to nest other objects, as shown above. Can someone tell me how to do it? What features or formats do I need to use?

resolvent:

'friends' is a jsonarray, and each item is a jsonobject. Just use put with jsonobject or jsonarray as the value. For an array, you must also specify an index