title: User Authentication using Windows logged in username in Java web application
body: <p>I want to authenticate user based on his username with which he is logged in in Windows.
  Actually I am building a web application for my organisation , so I don't want login page if the login user is already registered with us.
  The web application should automatically get username and match it with database and allow access.
  System.getproperty("user.name") gives server username.
  And there is no JavaScript code to get client machine username because of security reasons.</p>