Spring Boot集成Shiro后退出失败的问题

Spring Boot集成Shiro后，用下面这种方法退出，回调退出地址的之后并没有到回调的地址，而是重新进入了首页，有时候还会在logout之前就进入首页，但是这个时候session已经清了，然后就报错了，搞不懂为什么会出现这种情况，后面我用了另一种方法，至少到现在没有出现这个问题。希望有大神知道原因的回复一下，万分感激。

@RequestMapping("/logout")
public String logout() {
    return "redirect:" + casConfigProperties.getLogoutUrl();
}

@Bean(name = "shiroFilter")
public ShiroFilterFactoryBean getShiroFilterFactoryBean(DefaultWebSecurityManager securityManager, CasFilter casFilter) {
    ShiroFilterFactoryBean shiroFilterFactoryBean = new ShiroFilterFactoryBean();
    shiroFilterFactoryBean.setSecurityManager(securityManager);
    shiroFilterFactoryBean.setLoginUrl("/login");
    shiroFilterFactoryBean.setSuccessUrl("/main");
    shiroFilterFactoryBean.setUnauthorizedUrl("/403");

    // 添加casFilter到shiroFilter中
    Map<String, Filter> filters = new HashMap<>();
    filters.put("casFilter", casFilter);
    filters.put("authc", new MyFormAuthenticationFilter());
    shiroFilterFactoryBean.setFilters(filters);

    loadShiroFilterChain(shiroFilterFactoryBean);
    return shiroFilterFactoryBean;
}

private void loadShiroFilterChain(ShiroFilterFactoryBean shiroFilterFactoryBean) {
    Map<String, String> filterChainDefinitionMap = new LinkedHashMap<>();

    // authc：该过滤器下的页面必须登录后才能访问，它是Shiro内置的一个拦截器org.apache.shiro.web.filter.authc.FormAuthenticationFilter
    // anon: 可以理解为不拦截
    // user: 登录了就不拦截
    // roles["admin"] 用户拥有admin角色
    // perms["permission1"] 用户拥有permission1权限
    // filter顺序按照定义顺序匹配，匹配到就验证，验证完毕结束。
    // url匹配通配符支持：? * **,分别表示匹配1个，匹配0-n个（不含子路径），匹配下级所有路径

    // 1.shiro集成cas后，首先添加该规则
    filterChainDefinitionMap.put("/", "casFilter");
    filterChainDefinitionMap.put("/global/**", "anon");
    filterChainDefinitionMap.put("/logout", "anon");
    filterChainDefinitionMap.put("/passwordResetView", "anon");
    filterChainDefinitionMap.put("/passwordReset", "anon");
    filterChainDefinitionMap.put("/sendPhoneAuthenticationCode", "anon");
    filterChainDefinitionMap.put("/login", "casFilter,authc");
    filterChainDefinitionMap.put("/**", "user");
    shiroFilterFactoryBean.setFilterChainDefinitionMap(filterChainDefinitionMap);
}

这是我的解决办法，把退出改成用Shrio自己的退出过滤器，再里面设置退出后的回调地址，把控制器里的logout去掉。

至少到现在没有出现上面这种问题。

@Bean(name = "shiroFilter")
public ShiroFilterFactoryBean getShiroFilterFactoryBean(DefaultWebSecurityManager securityManager, CasFilter casFilter) {
    ShiroFilterFactoryBean shiroFilterFactoryBean = new ShiroFilterFactoryBean();
    shiroFilterFactoryBean.setSecurityManager(securityManager);
    shiroFilterFactoryBean.setLoginUrl("/login");
    shiroFilterFactoryBean.setSuccessUrl("/main");
    shiroFilterFactoryBean.setUnauthorizedUrl("/403");

    // 添加casFilter到shiroFilter中
    Map<String, Filter> filters = new HashMap<>();
    filters.put("casFilter", casFilter);
    filters.put("authc", new MyFormAuthenticationFilter());

    LogoutFilter logoutFilter = new LogoutFilter();
    logoutFilter.setRedirectUrl(casConfigProperties.getLogoutUrl());
    filters.put("logout", logoutFilter);

    shiroFilterFactoryBean.setFilters(filters);

    loadShiroFilterChain(shiroFilterFactoryBean);
    return shiroFilterFactoryBean;
}

private void loadShiroFilterChain(ShiroFilterFactoryBean shiroFilterFactoryBean) {
    Map<String, String> filterChainDefinitionMap = new LinkedHashMap<>();

    // authc：该过滤器下的页面必须登录后才能访问，它是Shiro内置的一个拦截器org.apache.shiro.web.filter.authc.FormAuthenticationFilter
    // anon: 可以理解为不拦截
    // user: 登录了就不拦截
    // roles["admin"] 用户拥有admin角色
    // perms["permission1"] 用户拥有permission1权限
    // filter顺序按照定义顺序匹配，匹配到就验证，验证完毕结束。
    // url匹配通配符支持：? * **,分别表示匹配1个，匹配0-n个（不含子路径），匹配下级所有路径

    // 1.shiro集成cas后，首先添加该规则
    filterChainDefinitionMap.put("/", "casFilter");
    filterChainDefinitionMap.put("/global/**", "anon");
    filterChainDefinitionMap.put("/logout", "logout");
    filterChainDefinitionMap.put("/passwordResetView", "anon");
    filterChainDefinitionMap.put("/passwordReset", "anon");
    filterChainDefinitionMap.put("/sendPhoneAuthenticationCode", "anon");
    filterChainDefinitionMap.put("/login", "casFilter,authc");
    filterChainDefinitionMap.put("/**", "user");
    shiroFilterFactoryBean.setFilterChainDefinitionMap(filterChainDefinitionMap);
}