Delete operation on cookie in selenium

Deleting all cookie at a time
Syntax
 driver.manage().deleteAllCookies();
 get firefox driver manger and call deleteAllCookies method

Code
   public class MyCookie_01 {
      public WebDriver driver;
      private String baseUrl;
   
   public static void main(String[] args) {
        MyCookie_01 mc = new MyCookie_01();
        mc.launch_browser();
    }

   public void launch_browser(){
        try{
         driver = new FirefoxDriver();
         baseUrl = "http://linkedin.com";
         driver.get(baseUrl);
         driver.manage().window().maximize();
       
         Cookie one = new Cookie.Builder("key1", "value").build();
         Cookie two = new Cookie.Builder("key2", "value").build();

         driver.manage().addCookie(one);
         driver.manage().addCookie(two);
       
         driver.manage().deleteAllCookies();
       
         Set<Cookie> cookies = driver.manage().getCookies();
         int countBefore = cookies.size(); //will give 0, since all cookies are deleted
      }
   }