In Spring how do you get the current user whose credentials are not part of the current http request?

Is there a "getCurrentUser" method in Spring to access the user that is currently part of a request - even i开发者_运维百科f that user's name is not being passed around as part of a web request?

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Since you have tagged your question with spring-security I assume your question is in same context. With spring-security you can retrieve current user as :

Object principal = SecurityContextHolder.getContext().getAuthentication().getPrincipal();
UserDetails userDetails = null;
if (principal instanceof UserDetails) {
  userDetails = (UserDetails) principal;
}
String userName = userDetails.getUsername();