Parsing JSON respone

if we have a JSON web service response like this:

"persons"
[
{
"person"{
"firstName": "John",
 "lastName": "Smith",
 "age": 25
}
}
{
"person"{
"firstName": "Catherine",
 "lastName": "Jones",
 "age": 35
}
}
]

this response is a JSON Array with the name "persons", this array consists of "person" JSON Objects.
to parse such a reponse:

public ArrayList<Person> getMessage(String response){
 JSONObject jsonResponse;
 ArrayList<Person> arrPersons=new ArrayList<Person>;
 try {
 // obtain the reponse
 jsonResponse = new JSONObject(response);
 // get the array
 JSONArray persons=jsonResponse.optJSONArray("persons");
 // iterate over the array and retrieve single person instances
 for(int i=0;i<persons.length();i++){
 // get person object
 JSONObject person=persons.getJSONObject(i);
 // get first name
 String firstname=person.optString("firstname");
 // get last name
 String lastname=person.optString("lastname");
 // get the age
 int age=person.optInt("age");

 // construct the object and add it to the arraylist
 Person p=new Person();
 p.firstName=firstname;
 p.lastName=lastname;
 p.age=age;
 arrPersons.add(p);
 }

 } catch (JSONException e) {

 e.printStackTrace();
 }

 return arrPersons;
 }

notice that we used the methods optJSONArray,optString,optInt instead of using getString,getInt because the opt methods return empty strings or zero integers if no elements are found. while the get methods throw an exception if the element is not found.

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