如何在JSF 2.0中使会话无效? [英] How to invalidate session in JSF 2.0?

问题描述

在JSF 2.0应用程序中使会话无效的最佳方法是什么?我知道JSF本身不处理会话.到目前为止，我可以找到

What is the best possible way to invalidate session within a JSF 2.0 application? I know JSF itself does not handle session. So far I could find

private void reset() {
    HttpSession session = (HttpSession) FacesContext.getCurrentInstance()
            .getExternalContext().getSession(false);
    session.invalidate();
}

1. 此方法正确吗?有没有办法不碰 ServletAPI?
2. 考虑以下情况，其中@SessionScoped UserBean处理 用户的注销登录.我在同一个bean中有此方法.现在 完成必要的数据库后调用reset()方法时 更新，我当前的会话作用域bean将发生什么?自从 甚至bean本身也存储在HttpSession中?

1. Is this method correct? Is there a way without touching the ServletAPI?
2. Consider a scenario wherein a @SessionScoped UserBean handles the login-logout of a user. I have this method in the same bean. Now when I call the reset() method after I'm done with necessary DB updates, what will happen to my current session scoped bean? since even the bean itself is stored in HttpSession?

推荐答案

首先，此方法正确吗?有没有不碰ServletAPI的方法?

您可以使用 ExternalContext#invalidateSession() 使会话无效，而无需获取Servlet API.

You can use ExternalContext#invalidateSession() to invalidate the session without the need to grab the Servlet API.

@ManagedBean
@SessionScoped
public class UserManager {

    private User current;

    public String logout() {
        FacesContext.getCurrentInstance().getExternalContext().invalidateSession();
        return "/home.xhtml?faces-redirect=true";
    }

    // ...

}

---

我当前的会话作用域bean将发生什么?因为甚至bean本身都存储在HttpSession中?

它在当前响应中仍然可以访问，但是在下一个请求中将不再可用.因此，在无效后触发重定向(新请求)非常重要，否则您仍在显示旧会话中的数据.可以通过在结果中添加faces-redirect=true来完成重定向，就像我在上面的示例中所做的那样.发送重定向的另一种方法是使用 ExternalContext#redirect() .

It will still be accessible in the current response, but it will not be there anymore in the next request. Thus it's important that a redirect (a new request) is fired after invalidate, otherwise you're still displaying data from the old session. A redirect can be done by adding faces-redirect=true to the outcome, as I did in the above example. Another way of sending a redirect is using ExternalContext#redirect().

public void logout() throws IOException {
    ExternalContext ec = FacesContext.getCurrentInstance().getExternalContext();
    ec.invalidateSession();
    ec.redirect(ec.getRequestContextPath() + "/home.xhtml");
}

但是，在这种情况下，它的使用值得怀疑，因为使用导航结果更为简单.

Its use is however questionable in this context as using a navigation outcome is simpler.

这篇关于如何在JSF 2.0中使会话无效?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！