1、导入需要的包、依赖

2、创建application.yml配置文件，编写druid的配置，以及在application.properties里面配置mybatis

3、连接数据库mybatis，并补充完整项目的包目录

pojo、mapper、service

4、在pojo里面编写User类

5、mapper里面编写UserMapper接口，并写一个查询方法

6、在resources下面创建的mybatis\mapper里面编写UserMapper.xml实现UserMapper类里面的方法?

7、在service里面编写UserService接口和UserServiceImpl实现类?

8、在测试类先测试一下?

测试ok，代表底层代码没问题

9、底层测试完没问题之后，就去改造UserRealm类

因为是从UserRealm类这一步开始从数据库中拿数据，之前的是伪造的数据

10、效果

数据库中的数据

11、在整合mybatis和添加druid的步骤中，不需要对MyController和ShiroConfig两个类进行改变

12、主要代码

12.1、pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.4</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.zhou</groupId>
    <artifactId>shiro-springboot</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>shiro-springboot</name>
    <description>shiro-springboot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
<!--        Subject:用户
            SecurityManager：管理所有用户
            Realm： 连接数据
-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!-- druid -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.21</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <!-- mybatis-spring-boot-starter ：整合-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>



        <!--        shiro整合spring的包-->
        <!-- https://mvnrepository.com/artifact/org.apache.shiro/shiro-spring -->
        <dependency>
            <groupId>org.apache.shiro</groupId>
            <artifactId>shiro-spring</artifactId>
            <version>1.4.1</version>
        </dependency>
        <!--        thymeleaf模板-->
        <dependency>
            <groupId>org.thymeleaf</groupId>
            <artifactId>thymeleaf-spring5</artifactId>
        </dependency>
        <dependency>
            <groupId>org.thymeleaf.extras</groupId>
            <artifactId>thymeleaf-extras-java8time</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

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

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

12.2、application.yml

spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    # 假如时区报错了，就增加一个时区的配置就ok了 serverTimezone=UTC
    url: jdbc:mysql://localhost:3306/mybatis?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
    username: root
    password: 123456
    type: com.alibaba.druid.pool.DruidDataSource # 自定义源数据

    #Spring Boot 默认是不注入这些属性值的，需要自己绑定
    #druid 数据源专有配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true

    #配置监控统计拦截的filters，stat:监控统计、log4j：日志记录、wall：防御sql注入
    #如果允许时报错  java.lang.ClassNotFoundException: org.apache.log4j.Priority
    #则导入 log4j 依赖即可，Maven 地址：https://mvnrepository.com/artifact/log4j/log4j
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500

12.3、UserRealm

package com.zhou.config;

import com.zhou.pojo.User;
import com.zhou.service.UserService;
import org.apache.shiro.authc.*;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.subject.PrincipalCollection;
import org.springframework.beans.factory.annotation.Autowired;

// 自定义的UserRealm   extends AuthorizingRealm
public class UserRealm extends AuthorizingRealm {

    @Autowired
    UserService userService;

    // 授权
    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principalCollection) {
        System.out.println("执行了====>授权doGetAuthorizationInfo");
        return null;
    }

    // 认证
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token) throws AuthenticationException {
        System.out.println("执行了====>认证doGetAuthorizationInfo");

//        // 用户名，密码 数据库中取出
//        String username = "root";
//        String password = "123456";

        UsernamePasswordToken userToken = (UsernamePasswordToken) token;

//        // 用户名判断
//        if (!userToken.getUsername().equals(username)){
//            return null; // 抛出异常  UnknownAccountException
//        }

        // 连接真实的数据库
        User user = userService.queryUserByName(userToken.getUsername());
        if (user == null){ // 没有这个人
            return null; // 抛出异常  UnknownAccountException
        }

        // 可以加密： MD5  MD5盐值加密
        // 密码认证 shiro做, 密码加密了
//        return new SimpleAuthenticationInfo("",password,"");
        return new SimpleAuthenticationInfo("", user.getPwd(), "");
    }
}

12.4、MyController

package com.zhou.controller;

import org.apache.shiro.SecurityUtils;
import org.apache.shiro.authc.IncorrectCredentialsException;
import org.apache.shiro.authc.UnknownAccountException;
import org.apache.shiro.authc.UsernamePasswordToken;
import org.apache.shiro.subject.Subject;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class MyController {

    @RequestMapping({"/", "/index"})
    public String toIndex(Model model){
        model.addAttribute("msg", "hello,shiro");
        return "index";
    }

    @RequestMapping("/user/add")
    public String add(){
        return "user/add";
    }

    @RequestMapping("/user/update")
    public String update(){
        return "user/update";
    }

    @RequestMapping("/toLogin")
    public String toLogin(){
        return "login";
    }

    @RequestMapping("/login")
    public String login(String username, String password, Model model){
        // 获取当前的用户
        Subject subject = SecurityUtils.getSubject();
        // 封装用户的登录数据
        UsernamePasswordToken token = new UsernamePasswordToken(username, password);

        try{
            subject.login(token);  // 执行登录的方法，如果没有异常就ok
            return "index";
        }catch (UnknownAccountException e){ // 用户名不存在
            model.addAttribute("msg", "用户名错误");
            return "login";
        }catch (IncorrectCredentialsException e){ // 密码不存在
            model.addAttribute("msg", "密码错误");
            return "login";
        }

    }


}