Selenium WebDriver

How to Close three different Browser Instances using 'driver.quit()' ?

 Below code will open three browsers (IE,Firefox and Chrome) and will open URL and finally it closes all the three opened browsers by 'driver.quit()' function.

 import java.util.ArrayList;  
 import java.util.List;  
 import org.openqa.selenium.WebDriver;  
 import org.openqa.selenium.chrome.ChromeDriver;  
 import org.openqa.selenium.firefox.FirefoxDriver;  
 import org.openqa.selenium.ie.InternetExplorerDriver;  
 public class Test   
 {  
   private List<WebDriver> drivers;  
     public Test( )  
      {  
          this.drivers = new ArrayList<WebDriver>();  
      }  
 public void CloseAll()  
      {  
     for(WebDriver d : drivers)  
       {  
       d.quit();  
       }  
      }  
 public static void main(String[] args)  
      {  
   Test1 sc = new Test1();  
   sc.IE("http://google.com");  
   sc.Firefox("http://google.com");  
   sc.Chrome("http://google.com");  
   sc.CloseAll();  
      }  
 //Internet Explorer driver  
 public void IE(String URL)  
     {  
   //Set you IEDriver path as per your System Path  
   System.setProperty("webdriver.ie.driver","S:\\IE Driver\\IEDriverServer.exe");  
   WebDriver driver = new InternetExplorerDriver();  
   driver.get(URL);  
   this.drivers.add(driver);  
      }  
 //Firefox driver  
 public void Firefox(String URL)  
     {  
   WebDriver driver = new FirefoxDriver();  
   driver.get(URL);  
   this.drivers.add(driver);  
     }  
 //Chrome driver  
 public void Chrome(String URL)  
     {  
   //Set you ChromeDriver path as per your System Path  
   System.setProperty("webdriver.chrome.driver","S://Chrome Driver//chromedriver.exe");  
   WebDriver driver = new ChromeDriver();  
   driver.get(URL);  
   this.drivers.add(driver);  
    }  
 }  

}