问如何在Java中创建嵌套的Json对象？

EN

{ 
 "command": "login",
 "uid": "123123123",
 "params":
  {
   "username": "sup",
   "password": "bros"
  }
}

loginInformation = new ArrayList<NameValuePair>(); 

JSONObject parentData = new JSONObject();
JSONObject childData = new JSONObject();

try {

    parentData.put("command", "login");
    parentData.put("uid", UID.getDeviceId());

    childData.put("username", username.getText().toString());
    childData.put("password", password.getText().toString());
    parentData.put("params", childData);

} catch (JSONException e) {
    e.printStackTrace();
}

loginInformation.add(new BasicNameValuePair("content", parentData.toString()));