自定义过滤器：

public class CustomFormAuthenticationFilter extends FormAuthenticationFilter {    @Override    protected boolean onAccessDenied(ServletRequest request, ServletResponse response) throws Exception {        if (isLoginRequest(request, response)) {            if (isLoginSubmission(request, response)) {                return executeLogin(request, response);            } else {                // 放行 allow them to see the login page ;)                return true;            }        } else {            HttpServletRequest httpRequest = WebUtils.toHttp(request);                        if (ShiroFilterUtils.isAjax(httpRequest)) {                                HttpServletResponse httpServletResponse = WebUtils.toHttp(response);                  httpServletResponse.sendError(ShiroFilterUtils.HTTP_STATUS_SESSION_EXPIRE);                                 return false;                } else {                  saveRequestAndRedirectToLogin(request, response);             }              return false;        }    }        /**     * 判断ajax请求     * @param request     * @return     */    boolean isAjax(HttpServletRequest request){        return  (request.getHeader("X-Requested-With") != null  && "XMLHttpRequest".equals( request.getHeader("X-Requested-With").toString())   ) ;    }    }

封装ajax

var Error = function () {        return {        // 初始化各个函数及对象        init: function () {        },                // 显示或者记录错误        displayError: function(response, ajaxOptions, thrownError) {            if (response.status == 404) {
   // 页面没有找到                pageContent.load($("#hdnContextPath").val() + "/page/404.action");            } else if (response.status == 401) {
   // session过期                SweetAlert.errorSessionExpire();            } else if (response.status == 507) {
   // 用户访问次数太频繁                 SweetAlert.error("您的访问次数太频繁, 请过一会再试...");            } else {
   //其他错误                window.location = $("#hdnContextPath").val() + "/page/500.action";              }            console.log(thrownError);        }    };}();jQuery(document).ready(function() {    Error.init();});

JS的引用处如下：

App.blockUI();        $.ajax({        url: $("#hdnContextPath").val() + "/feedback/queryFeedBackDetail.action",        type: "POST",        async: false,        data: {
    "feedbackId": feedbackId, "userId": userId, "status": status},        success: function(data) {            // 忽略        },        error: function (response, ajaxOptions, thrownError) {            App.unblockUI();            Error.displayError(response, ajaxOptions, thrownError);                        }    });