public interface UserDetailsChecker
UserDetailsServiceto check the status of the loaded UserDetails object. Typically this will involve examining the various flags associated with the account and raising an exception if the information cannot be used (for example if the user account is locked or disabled), but a custom implementation could perform any checks it wished.
The intention is that this interface should only be used for checks on the persistent data associated with the user. It should not involved in making any authentication decisions based on a submitted authentication request.
void check(UserDetails toCheck)
toCheck- the UserDetails instance whose status should be checked.