创建UserDetailsService实现类

package com.security.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.security.domain.LoginUser;
import com.security.domain.User;
import com.security.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Component;
import java.util.Objects;

@Component
public class UserDetailsServiceImpl implements UserDetailsService {

    @Autowired
    private UserMapper userMapper;

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

        //查询用户信息
        LambdaQueryWrapper<User> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(User::getUserName,userName);
        User user = userMapper.selectOne(queryWrapper);
        //没有查询到用户抛出异常
        if(Objects.isNull(user)){
            //异常会被ExceptionTranslationFilter捕获到
           throw new RuntimeException("用户名或者密码错误");
        }

        //todo 查询对应的权限信息

        //把数据封装成UserDetails返回
        return new LoginUser(user);
    }
}

@Data
@NoArgsConstructor
@AllArgsConstructor
public class LoginUser implements UserDetails {

    private User user;


    @Override
    public Collection<? extends GrantedAuthority> getAuthorities() {
        return null;
    }

    @Override
    public String getPassword() {
        return user.getPassword();
    }

    @Override
    public String getUsername() {
        return user.getUserName();
    }

    @Override
    public boolean isAccountNonExpired() {
        return true;
    }

    @Override
    public boolean isAccountNonLocked() {
        return true;
    }

    @Override
    public boolean isCredentialsNonExpired() {
        return true;
    }

    @Override
    public boolean isEnabled() {
        return true;
    }
}