How to handle Authentication PopUp using Selenium?

Sometime we have to automate websites which shows authentication Pop Up like mentioned below:

In order to automate this PopUp, we will pass UserId and Password via URL:

http://username:password@anytestwebsite.com

Java Script:

String URL = "http://" + username + ":" + password + "@" + anytestwebsite.com;
driver.get(URL);
Alert alert = driver.switchTo().alert();
alert.accept();