解決Shiro 處理ajax請求攔截登錄超時的問題

$.ajaxSetup({
    complete:function(XMLHttpRequest,textStatus){
          if(textStatus=="parsererror"){
               $.messager.alert('提示信息', "登陸超時！請重新登陸！", 'info',function(){
                   window.location.href = 'login.jsp';
               });
          } else if(textStatus=="error"){
              $.messager.alert('提示信息', "請求超時！請稍後再試！", 'info');
          }
    }
});

package com.cnpc.framework.filter;
import org.apache.shiro.SecurityUtils;
import org.apache.shiro.session.Session;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
 * * filter過濾器，獲取項目路徑，設置ajax超時標識
 * @author billJiang QQ:475572229
 */
public class SystemFilter implements Filter {
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException,
            ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        System.out.println(request.getRequestURL());
        String basePath = request.getContextPath();
        request.setAttribute("basePath", basePath);
        if (!SecurityUtils.getSubject().isAuthenticated()) {
            //判斷session裡是否有用戶信息
            if (request.getHeader("x-requested-with") != null
                    && request.getHeader("x-requested-with").equalsIgnoreCase("XMLHttpRequest")) {
                //如果是ajax請求響應頭會有，x-requested-with
                response.setHeader("session-status", "timeout");//在響應頭設置session狀態
                return;
            }
        }
        filterChain.doFilter(request, servletResponse);
    }
    @Override
    public void destroy() {
        // TODO Auto-generated method stub
    }
    @Override
    public void init(FilterConfig arg0) throws ServletException {
        // TODO Auto-generated method stub
    }
}

function ajaxPost(url, params, callback) {
    var result = null;
    var headers={};
    headers['CSRFToken']=$("#csrftoken").val();
    $.ajax({
        type : 'post',
        async : false,
        url : url,
        data : params,
        dataType : 'json',
        headers:headers,
        success : function(data, status) {
            result = data;
            if(data&&data.code&&data.code=='101'){
                modals.error("操作失敗，請刷新重試，具體錯誤："+data.message);
                return false;
            }
            if (callback) { 
                callback.call(this, data, status);
            }
        },
        error : function(err, err1, err2) {
            console.log("ajaxPost發生異常，請仔細檢查請求url是否正確，如下面錯誤信息中出現success，則表示csrftoken更新，請忽略");
            console.log(err.responseText);
            if(err && err.readyState && err.readyState == '4'){
                var sessionstatus=err.getResponseHeader("session-status");
                if(sessionstatus=="timeout"){
                    //如果超時就處理 ，指定要跳轉的頁面
                    window.location.href=basePath+"/" ;
                }
                else{//csrf異常
                    var responseBody = err.responseText;
                    if (responseBody) {
                        responseBody = "{'retData':" + responseBody;
                        var resJson = eval('(' + responseBody + ')');
                        $("#csrftoken").val(resJson.csrf.CSRFToken);
                        this.success(resJson.retData, 200);
                    }
                    return;
                }
            }           
            modals.error({
                text : JSON.stringify(err) + '<br/>err1:' + JSON.stringify(err1) + '<br/>err2:' + JSON.stringify(err2),
                large : true
            });
        }
    });
    return result;
}

var _old_load = jQuery.fn.load;
jQuery.fn.load = function( url, params, callback ) {
    //update for HANZO, 2016/12/22
    if (typeof url !== "string" && _old_load) {
        return _old_load.apply( this, arguments );
    }
    var selector, type, response,
        self = this,
        off = url.indexOf( " " );
    if ( off > -1 ) {
        selector = jQuery.trim( url.slice( off ) );
        url = url.slice( 0, off );
    }
    if ( jQuery.isFunction( params ) ) {
        callback = params;
        params = undefined;
    } else if ( params && typeof params === "object" ) {
        type = "POST";
    }
    if ( self.length > 0 ) {
        jQuery.ajax( {
            url: url,
            beforeSend: function( xhr ) {  
                    xhr.setRequestHeader('X-Requested-With', {toString: function(){ return ''; }});  
            },  
            type: type || "GET", 
            dataType: "html",
            data: params
        } ).done( function( responseText ) {
            //console.log(responseText);
            response = arguments;
            //頁面超時跳轉到首頁
            if(responseText.startWith("<!--login_page_identity-->")){
                window.location.href=basePath+"/";
            }else{
                self.html(selector ?
                    jQuery("<div>").append(jQuery.parseHTML( responseText )).find(selector) :
                    responseText);
            }
        } ).always( callback && function( jqXHR, status ) {
            self.each( function() {
                callback.apply( this, response || [ jqXHR.responseText, status, jqXHR ] );
            } );
        } );
    }
    return this;
};