1，新建springboot專案，引入spring security 包，springboot自動啟動springsecurity 配置

2，啟動專案並訪問會提示輸入使用者名稱和密碼

3，繼承UserDetailsService，重寫loaduserByUsername()方法，其中入參為登入傳入的使用者名稱，返回引數為

new User(ss,password,grantedAuthorityList) 返回使用者名稱，密碼，許可權資訊。

   @Component

public class SpringSecurityConfig implements UserDetailsService {

    private static final 
 
Logger LOGGER = LoggerFactory.getLogger(SpringSecurityConfig.class);

    @Autowired
private PasswordEncoder passwordEncoderDemo;

    @Autowired
private UserDetails userDetailsDemo;

    @Override
public UserDetails loadUserByUsername(String s) throws UsernameNotFoundException {

        LOGGER.info("
 
傳入的名稱是{}",s);

        String ss = passwordEncoderDemo.encode(s);

        String password = userDetailsDemo.getPassword();

        List<GrantedAuthority> grantedAuthorityList = (List<GrantedAuthority>) userDetailsDemo.getAuthorities();

        return new User(ss,password,grantedAuthorityList);
    }
}

4，