一、添加依赖

 <!--spring security-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>

        <!--web-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!--test-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!-- mybatis-plus -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.5.1</version>
        </dependency>

        <!-- lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId> <optional>true</optional>
        </dependency>

        <!-- mysql-connector -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.32</version>
        </dependency>

二、创建文件结构+主方法扫描mapper

三、创建数据库及对应实体，并配置yml文件

t_user：用户表

t_anth：角色表

user_anth：用户、角色关系表

User：

@Data//生成get、set方法
public class Users {
    @JsonSerialize(using = ToStringSerializer.class)//防止json传过来导致精度缺失
    private Long id;
    private String userName;
    private String account;
    private String password;
    private List<String> anths;//用户权限
}

application.yml:

server:
  port: 8080
spring:
  #  数据源
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
//数据库地址
    url: jdbc:mysql://127.0.0.1:3306/2_27user?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC
    username: root//账号
    password: 123456//密码

mybatis:
//mybits文件（维护sql）语句
  mapper-locations: classpath:mapper/*.xml

logging:
  level:
    com.woniu.dao: debug
  pattern:
    console: '%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%n'

四、维护sql语句，在mapper添加方法

UserMapper.xml：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.security.mapper.UserMapper">

    <resultMap id="userMap" type="com.security.entity.Users">
        <id property="id" column="id"></id>
        <result property="userName" column="user_name"></result>
        <result property="account" column="account"></result>
        <result property="password" column="password"></result>
        <collection property="anths" ofType="java.lang.String">
            <result column="anth_code"></result>
        </collection>
    </resultMap>
    <select id="getUserInfoByAccount" resultMap="userMap">
        select
            us.id,
            us.user_name,
            us.account,
            us.password,
            ta.anth_code
        from
            t_user us
                left join user_anth ua on us.id=ua.user_id
                left join t_anth ta on ua.anth_id=ta.id
        where account =#{account}
    </select>
</mapper>

UserMapper：

@Repository
public interface UserMapper {
    /**
     * 根据账号查看用户信息及其权限
     * @param account
     * @return
     */
    Users getUserInfoByAccount(String account);
}

五、config层

SercurityConfig:

@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    @Autowired
    private SecurityService securityService;

    @Override
    public void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(securityService);
    }

    /**
     * 数据加密类
     * @return
     */
    @Bean
    public PasswordEncoder passwordEncoder(){
        return new BCryptPasswordEncoder();
    }
}

六、Service层

SecurityService：

@Service
public class SecurityService implements UserDetailsService {
    @Autowired
    private PasswordEncoder passwordEncoder;
    @Autowired
    private UserMapper userMapper;

    /**
     * username：页面传过来的username
     * @param username
     * @return
     * @throws UsernameNotFoundException
     */
    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {

        Users users=userMapper.getUserInfoByAccount(username);
        if(users!=null) {
            String anths=String.join(",",users.getAnths());
            //username 数据库产查用户信息
            return new User(users.getUserName(), passwordEncoder.encode(users.getPassword()),
                    AuthorityUtils.commaSeparatedStringToAuthorityList(anths));
        }
        else {
            throw new UsernameNotFoundException("该用户不存在");
        }
    }
}