*/
public UserDetails loadUserByUsername(String username){
log.debug("loggin with username: {"+username+"}");
log.debug("loggin with user dao instance: {"+this.accountDao+"}");
//filter username.
final HTMLInputFilter filter = new HTMLInputFilter(true);
username = filter.filter(username);
final UserAccount user = this.accountDao.getUserByUsername(username);
log.debug("fetch username filtered: {"+user+"}");
if (user == null) {
log.error("user not found :{"+username);
throw new UsernameNotFoundException("user not found");