spring security 封装userdetail配置

@Service
public class UserDetailsServiceImpl implements UserDetailsService {
    @Resource
    UserService userService;


    /**
     * @Classname UserDetailsServiceImpl
     * @Description 自定义一个UserDetailsService接口实现类进行用户认证信息封装
     * @Date 2021-12-11
     * @Created by samLi
     */
    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
        //1.查找用户
        User user = userService.findUserByUsername(username);
        //2.查找用户对应的权限
        List<Authority> authorities = userService.getUserAuthority(username);
        //3.封装到SimpleGrantedAuthority中
        //流式语法
        List<SimpleGrantedAuthority> simpleGrantedAuthorities = authorities.stream().map(authority -> new
                SimpleGrantedAuthority(authority.getAuthority())).collect(Collectors.toList());
        if (user != null) {
            UserDetails userDetails = new org.springframework.security.core.userdetails.User(user.getUsername(), user.getPassword(), simpleGrantedAuthorities);
            return userDetails;
        } else {
            // 如果查询的用户不存在（用户名不存在），必须抛出此异常
            throw new UsernameNotFoundException("当前用户不存在！");
        }

    }
}