Selenium Webdriver getting a cookie value

Question

I am trying to get a cookie value but keep getting an error of

I am calling

Answer 1

    Set cook =  driver.manage().getCookies();
    for(Cookie cooks : cook) 
    {

    System.out.println(cooks.getName());
    }

    Cookie t = driver.manage().getCookieNamed("_gid");
    if(t!=null){
    String s1 = t.getValue();
    System.out.println("The Cookie value is : " + s1);
               }