/*
  * (non-Javadoc)
  *
  * @see
  * org.springframework.security.core.userdetails.UserDetailsService#loadUserByUsername
  * (java.lang.String)
  */
 public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
   User user = roleResourcesService.getUserByUsername(username);
   if (user == null) {
     throw new UsernameNotFoundException("Could not find user " + username);
   }
   Set<UserRole> roles = roleResourcesService.findUserRoles(user.getId());
   user.setRoles(roles);
   // 用户权限
   Collection<GrantedAuthority> grantedAuths = obtionGrantedAuthorities(user);
   return new CustomUserDetails(user, grantedAuths);
 }