public interface UserDetailsPasswordService {
   UserDetails updatePassword(UserDetails user, String newPassword);
}

public class UserService1 implements UserDetailsService {
	@Resource
	private UsersMapper usersMapper;
	@Override
	public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
		Optional<Users> optionalUsers = Optional.ofNullable(usersMapper.loadUserByUsername(username));
		return optionalUsers.orElseThrow(() -> new UsernameNotFoundException("找不到用戶名"));
	}
}

@Bean
public UserService1 userService1() throws Exception {
    return new UserService1();
}

@Bean
public PasswordEncoder passwordEncoder() {
    return PasswordEncoderFactories.createDelegatingPasswordEncoder();
}

public static PasswordEncoder createDelegatingPasswordEncoder() {
    // 省略了一堆代碼
   String encodingId = "bcrypt";
   Map<String, PasswordEncoder> encoders = new HashMap<>();
   encoders.put(encodingId, new BCryptPasswordEncoder());
   encoders.put("MD5", new org.springframework.security.crypto.password.MessageDigestPasswordEncoder("MD5"));
   encoders.put("noop", org.springframework.security.crypto.password.NoOpPasswordEncoder.getInstance());
   return new DelegatingPasswordEncoder(encodingId, encoders);
}

String encodingId = "bcrypt";
encoders.put(encodingId, new BCryptPasswordEncoder());
return new DelegatingPasswordEncoder(encodingId, encoders);

public DelegatingPasswordEncoder(String idForEncode, Map<String, PasswordEncoder> idToPasswordEncoder,
      String idPrefix, String idSuffix) {
    // 省略一堆代碼
   this.idForEncode = idForEncode;
   this.passwordEncoderForEncode = idToPasswordEncoder.get(idForEncode);
   this.idToPasswordEncoder = new HashMap<>(idToPasswordEncoder);
   this.idPrefix = idPrefix;
   this.idSuffix = idSuffix;
}

this.idForEncode = idForEncode;
this.passwordEncoderForEncode = idToPasswordEncoder.get(idForEncode);

this.idForEncode = "bcrypt";
this.passwordEncoderForEncode = new BCryptPasswordEncoder();

@Override
public String encode(CharSequence rawPassword) {
   return this.idPrefix + this.idForEncode + this.idSuffix + this.passwordEncoderForEncode.encode(rawPassword);
}

public static PasswordEncoder createDelegatingPasswordEncoder() {
   String encodingId = "無敵加密";
   Map<String, PasswordEncoder> encoders = new HashMap<>();
   encoders.put(encodingId, new 無敵加密PasswordEncoder());
    // 省略一堆代碼
   return new DelegatingPasswordEncoder(encodingId, encoders);
}

public class UserService implements UserDetailsService, UserDetailsPasswordService {
   @Resource
   private UsersMapper usersMapper;
   /**
    * 升級(jí)用戶密碼為當(dāng)前加密方式
    *
    * @param user        要修改的用戶, 這個(gè)用戶必須有 id
    * @param newPassword 新的密碼, 該密碼已經(jīng)被 passwordEncoder 加密
    * @return
    */
   @Override
   public UserDetails updatePassword(UserDetails user, String newPassword) {
      if (user instanceof Users users) {
         users.setPassword(newPassword);
         usersMapper.updateByPrimaryKeySelective(users);
      }
      return user;
   }
   @Override
   public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
      Optional<Users> optionalUsers = Optional.ofNullable(usersMapper.loadUserByUsername(username));
      return optionalUsers.orElseThrow(() -> new UsernameNotFoundException("找不到用戶"));
   }
}

@Bean
public AuthenticationManager authenticationManager(HttpSecurity http) throws Exception {
   AuthenticationManagerBuilder authenticationManagerBuilder = http.getSharedObject(AuthenticationManagerBuilder.class);
   authenticationManagerBuilder.authenticationProvider(/* 你的認(rèn)證七 */)
         .userDetailsService(/* 加載用戶方式 */)
         .passwordEncoder(/* 密碼加密方式 */)
         .userDetailsPasswordManager(/* 第三種更新加密的方式 */);
   return authenticationManagerBuilder.build();
}