java – 使用JSF 2.0 / Facelets,有没有办法将全局监听器附加到

Is there a way to attach a global listener to all AJAX calls in JSF? Maybe through a phase listener or something?

是的,PhaseListener可以做到. A SystemEventListener也. A Filter也.

如果您在JSF上下文中,那么可以检查当前请求是否为ajax请求.

if (FacesContext.getCurrentInstance().getPartialViewContext().isAjaxRequest()) {
    // It's an ajax request.
}

如果你不在JSF上下文,例如在一个过滤器中,那么可以检查当前的请求是否是JSF ajax请求.

if ("partial/ajax".equals(request.getHeader("Faces-Request"))) {
    // It's a JSF ajax request.
}

Here is the conundrum… Lets say you’re using f:ajax tags and something like apache shiro and you let your session expire. Then you come back and click a button that has an f:ajax attached to it. The server will respond with a 302 redirect to the login page.

The user sees nothing. They can repeatedly click and invoke the ajax call,but to them the app is just “dead.”

强制ajax请求的重定向需要特殊的XML响应.当您在JSF上下文中时,ExternalContext#redirect()已经将其隐含地考虑在内.所有你需要做的是写这个：

FacesContext.getCurrentInstance().getExternalContext().redirect(url);

如果你不在JSF上下文,例如在筛选器中,您需要自己编写整个XML响应.例如.

response.setContentType("text/xml");
response.getWriter()
    .append("<?xml version="1.0" encoding="UTF-8"?>")
    .printf("<partial-response><redirect url="%s"></redirect></partial-response>",url);