ServiceHandler - JSONObject

Olá…boa noite!
Queria saber se alguém poderia me ajudar com o problema que estou tendo conforme abaixo:

Estou tentando popular minha “response” porém ela sempre está saindo null.

Segue meu código.

package br.com.tapanovisual.tvisual;

import org.json.JSONArray;

import org.json.JSONException;

import org.json.JSONObject;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import java.util.ArrayList;

import java.util.List;

/**Created by thiago.c.melo on 15/03/2016.*/
public class ServiceHandler {

public String response;
public final static List<String> lista = null;
public final static int GET = 1;
public final static int POST = 2;

public ServiceHandler(){

}

public String ServiceCall(String url, int method){
    return this.ServiceCall(url, method, null);
}

private String ServiceCall(String url, int method, Object o) {

try {
        URL url2 = new URL("http://tapanovisual.esy.es/selectUltimasReservas.php");
        HttpURLConnection conn = (HttpURLConnection) url2.openConnection();
        conn.connect();

//Testando metodo enviado
        if (method == POST){

}else if(method == GET){

InputStream stream = conn.getInputStream();
            BufferedReader buffer = new BufferedReader(new InputStreamReader(stream));
            StringBuffer sb = new StringBuffer();

String line = "";
            while ((line = buffer.readLine()) != null){
                sb.append(line);
            }

String finalJson = sb.toString();
            JSONObject parentObject = new JSONObject(finalJson);

response = parentObject.getString("nome");

}

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

return response;
}

}

Abaixo segue meu Json.

{“estabelecimentos”:[{“id”:“1”,“nome”:“Raphas Fashion Hair”},{“id”:“2”,“nome”:“Estacao Beleza”},{“id”:“3”,“nome”:“Beleza Natural”}],“sucesso”:1}

Obrigado!