如何在Android中使用多个数据创建JSON

I've to create in android like this,

"draft":
 [
  { "firstName": "Glen", "lastName": "McGrath" },
  { "firstName": "Steve", "lastName": "Vaugh" }
 ]

How can I create this type of JSON? I've been through some links but not getting correct output.

So far, I've tried this code,

JSONObject newObj = null ;              
                for(int h=0; h<3; h++)
                {
                    newObj = new JSONObject();
                    newObj.put("firstName", "" + h);
                    newObj.put("lastName", "" + h);
                }

                JSONArray postjson = new JSONArray();
                postjson.put(newObj);

But, not getting any output while decoding this json in php file.

Below is my .php file to decode json,

$json = $_SERVER['HTTP_JSON'];
$json = json_decode($json, true);
mysql_connect("localhost", "root", "") or die(mysql_error()) ; 
mysql_select_db("retail_menu") or die(mysql_error()) ; 
    foreach($json as $value)
    {

        foreach($value as $value1)
        {
            echo $data1 = $value1['firstName'];
            echo $data2 = $value1['lastName'];

            $query = "INSERT INTO `rr_friendid` (friend_id, friend_name) VALUES ('$data1','$data2')";
        var_dump($query);
        mysql_query($query);
    }

}

But, I can't see any values store in database. I don't know where I'm wrong, in creating json or while decoding it. How can I create json as the above I mentioned?

The following json you require is not valid:

"draft":
 [
  { "firstName": "Glen", "lastName": "McGrath" },
  { "firstName": "Steve", "lastName": "Vaugh" }
 ]

It should have an enclosing braze.

{
    "draft": [
        {
            "firstName": "Glen",
            "lastName": "McGrath"
        },
        {
            "firstName": "Steve",
            "lastName": "Vaugh"
        }
    ]
}

To check valid json format, see onlineJsonEditor.