1、新建一个module,创建一个maven web项目

2、在WEB-INF下新建一个web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
         http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
    <filter>
        <filter-name>shiroFilter</filter-name>
        <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>shiroFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:spring/spring.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <servlet>
        <servlet-name>DispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring/springmvc.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
        <async-supported>true</async-supported>
    </servlet>

    <servlet-mapping>
        <servlet-name>DispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <!-- 注册spring提供的针对POST请求的中文乱码问题 -->
    <filter>
        <filter-name>CharacterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>CharacterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>

3、在resource下新建一个Spring文件夹，在Spring文件夹下新建spring.xml和springmvc.xml

Spring.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       https://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/mvc
       http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <bean id="shiroFilter" class="org.apache.shiro.spring.web.ShiroFilterFactoryBean">
        <property name="securityManager" ref="securityManager"></property>
        <property name="loginUrl" value="login.html"></property>
        <property name="unauthorizedUrl" value="403.html"></property>
        <property name="filterChainDefinitions">
            <value>
                /login.html = anon
                /subLogin = anon
                /* = authc
            </value>
        </property>
    </bean>

    <!--创建SecurityManager对象-->
    <bean id="securityManager" class="org.apache.shiro.web.mgt.DefaultWebSecurityManager">
        <property name="realm" ref="realm"></property>
    </bean>

    <bean id="realm" class="com.zjc.shiro.realm.CustomRealm">
        <property name="credentialsMatcher" ref="credentialsMatcher" />
    </bean>

    <bean class="org.apache.shiro.authc.credential.HashedCredentialsMatcher" id="credentialsMatcher">
        <property name="hashAlgorithmName" value="md5"/>
        <property name="hashIterations" value="1"/>
    </bean>
</beans>

springmvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       https://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/mvc
       http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:component-scan base-package="com.zjc.controller"/>

    <mvc:annotation-driven />
    
    <mvc:resources mapping="/*" location="/" />
</beans>

4、新建自定义Realm

package com.zjc.shiro.realm;

import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationInfo;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.authc.SimpleAuthenticationInfo;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.authz.SimpleAuthorizationInfo;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.subject.PrincipalCollection;
import org.apache.shiro.util.ByteSource;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

public class CustomRealm extends AuthorizingRealm {

    Map<String, String> userMap = new HashMap<>();

    {
        userMap.put("zjc", "bfe76993b7209d38fe91de3021fa2b36");
        super.setName("customRealm");
    }

    /**
     * 自定义授权过程
     *
     * @param principals
     * @return
     */
    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
        String userName = (String) principals.getPrimaryPrincipal();

        //从数据或者缓存中获取角色数据
        Set<String> roles = getRolesByUserName(userName);

        //从数据或者缓存中获取权限数据
        Set<String> permissions = getPermissionsByUserName(userName);


        SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();

        simpleAuthorizationInfo.setStringPermissions(permissions);
        simpleAuthorizationInfo.setRoles(roles);
        return simpleAuthorizationInfo;


    }

    private Set<String> getPermissionsByUserName(String userName) {
        Set<String> sets = new HashSet<>();
        sets.add("user:delete");
        sets.add("user:add");
        return sets;

    }

    private Set<String> getRolesByUserName(String userName) {
        Set<String> sets = new HashSet<>();
        sets.add("admin");
        sets.add("user");
        return sets;

    }

    /**
     * 自定义认证的过程
     *
     * @param token
     * @return
     * @throws AuthenticationException
     */
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token) throws AuthenticationException {

        //1、从主体传过来的认证信息中，获得用户名
        String userName = (String) token.getPrincipal();

        //2、通过用户名到数据库中获取凭证
        String password = getPasswordByUserName(userName);

        if (password == null) {
            return null;
        }

        SimpleAuthenticationInfo authenticationInfo = new SimpleAuthenticationInfo("zjc", password, "customRealm");

        //设置盐
        authenticationInfo.setCredentialsSalt(ByteSource.Util.bytes("zjc"));
        return authenticationInfo;
    }

    /**
     * 模拟数据库查询凭证
     *
     * @param userName
     * @return
     */
    private String getPasswordByUserName(String userName) {
        return userMap.get(userName);
    }


}

5、新建login.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>登陆</title>
</head>
<body>
 <form action="subLogin" method="post">
     用户名：<input type="text" name="username" /><br>
     密码：<input type="password" name="password" /><br>
     <input type="submit" value="登陆">
 </form>
</body>
</html>

6、创建UserController

package com.zjc.controller;

import com.zjc.entity.User;
import org.apache.shiro.SecurityUtils;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.UsernamePasswordToken;
import org.apache.shiro.subject.Subject;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;


@Controller
public class UserController {

    @RequestMapping(value = "/subLogin",method = RequestMethod.POST,
            produces = "application/json;charset=utf-8")
    @ResponseBody
    public String subLogin(User user){
        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken(user.getUsername(),user.getPassword());

        try {
            subject.login(token);
        } catch (AuthenticationException e) {
           return e.getMessage();
        }
        return "登陆成功";
    }
}

7、创建User实体类

package com.zjc.entity;

public class User {

    private String username;

    private String password;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}