public Collection<? extends GrantedAuthority> getAuthorities() {
		if (principal == null) {
			return Collections.emptyList();
		}
		return Collections.unmodifiableCollection(principal.getAuthorities());
	}
public Collection < ? extends GrantedAuthority > getAuthorities ( ) { if ( principal == null ) { return Collections . emptyList ( ) ; } return Collections . unmodifiableCollection ( principal . getAuthorities ( ) ) ; }
A list of roles for the authenticated user.
@return a list of roles