A LoginContext is a Java class that is used to set up the login process, actually login, and get the Subject if the login is successful. It has four main methods, as follows:

• LoginContext("JAASExample", newUsernamePasswoerdCallbackHandler()) is the constructor. It takes the string used in the login.config file as its first parameter, and a callback handler, which does the real work, as its second parameter. (We'll discuss callback handlers next.)
  
  
• login() actually attempts the login, subject to the rules specified in the login.config file.
  
  
• getSubject() returns the authenticated Subject if the login was an overall success.
  
  
• logout() logs the Subject off of the LoginContext.