给一个springboot项目中使用shiro的例子

当然可以，以下是一个使用 Shiro 的 Spring Boot 项目的示例：

首先，您需要在 pom.xml 文件中添加以下依赖项：

<dependency>
    <groupId>org.apache.shiro</groupId>
    <artifactId>shiro-spring-boot-web-starter</artifactId>
    <version>1.4.2</version>
</dependency>

接下来，您需要在 application.properties 文件中配置 Shiro：

# Shiro 配置
shiro:
  # 登录 URL
  loginUrl: /login
  # 登录成功后跳转的 URL
  successUrl: /index
  # 未授权 URL
  unauthorizedUrl: /unauthorized
  # Shiro 过滤器链配置
  filterChainDefinitions: /static/**=anon\n/login=anon\n/logout=logout\n/**=authc

然后，您需要创建一个 Shiro 配置类：

@Configuration
public class ShiroConfig {

    /**
     * 创建 Shiro 过滤器工厂
     */
    @Bean
    public ShiroFilterFactoryBean shiroFilterFactoryBean(SecurityManager securityManager) {
        ShiroFilterFactoryBean shiroFilterFactoryBean = new ShiroFilterFactoryBean();
        shiroFilterFactoryBean.setSecurityManager(securityManager);
        shiroFilterFactoryBean.setLoginUrl("/login");
        shiroFilterFactoryBean.setSuccessUrl("/index");
        shiroFilterFactoryBean.setUnauthorizedUrl("/unauthorized");

        Map<String, String> filterChainDefinitionMap = new LinkedHashMap<>();
        filterChainDefinitionMap.put("/static/**", "anon");
        filterChainDefinitionMap.put("/login", "anon");
        filterChainDefinitionMap.put("/logout", "logout");
        filterChainDefinitionMap.put("/**", "authc");

        shiroFilterFactoryBean.setFilterChainDefinitionMap(filterChainDefinitionMap);
        return shiroFilterFactoryBean;
    }

    /**
     * 创建 SecurityManager
     */
    @Bean
    public SecurityManager securityManager() {
        DefaultWebSecurityManager securityManager = new DefaultWebSecurityManager();
        securityManager.setRealm(realm());
        return securityManager;
    }

    /**
     * 创建 Realm
     */
    @Bean
    public Realm realm() {
        return new MyRealm();
    }

    /**
     * 开启 Shiro 注解支持
     */
    @Bean
    public AuthorizationAttributeSourceAdvisor authorizationAttributeSourceAdvisor(SecurityManager securityManager) {
        AuthorizationAttributeSourceAdvisor advisor = new AuthorizationAttributeSourceAdvisor();
        advisor.setSecurityManager(securityManager);
        return advisor;
    }

    /**
     * 开启 Shiro AOP 支持
     */
    @Bean
    public DefaultAdvisorAutoProxyCreator defaultAdvisorAutoProxyCreator() {
        DefaultAdvisorAutoProxyCreator creator = new DefaultAdvisorAutoProxyCreator();
        creator.setProxyTargetClass(true);
        return creator;
    }
}

最后，您需要创建一个 Realm 类来处理身份验证和授权：

public class MyRealm extends AuthorizingRealm {

    /**
     * 处理授权
     */
    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
        SimpleAuthorizationInfo authorizationInfo = new SimpleAuthorizationInfo();
        authorizationInfo.addRole("admin");
        authorizationInfo.addStringPermission("user:list");
        return authorizationInfo;
    }

    /**
     * 处理身份验证
     */
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token) throws AuthenticationException {
        String username = (String) token.getPrincipal();
        String password = new String((char[]) token.getCredentials());

        if (!"admin".equals(username)) {
            throw new UnknownAccountException("用户名或密码错误");
        }

        if (!"123456".equals(password)) {
            throw new IncorrectCredentialsException("用户名或密码错误");
        }

        return new SimpleAuthenticationInfo(username, password, getName());
    }
}

这就是一个简单的使用 Shiro 的 Spring Boot 项目的示例。