Ajax请求处理Session超时

传统的基于B/S的应用中，Session会话超时后通常是跳转到应用的首页，但Ajax请求的处理方式有些不同，下面简单介绍一下Ajax请求的Session超时处理(超时后返回首页)

1.首先创建一个Filter

[java]  view plain copy

1. import java.io.IOException;  
2.   
3. import javax.servlet.Filter;  
4. import javax.servlet.FilterChain;  
5. import javax.servlet.FilterConfig;  
6. import javax.servlet.ServletException;  
7. import javax.servlet.ServletRequest;  
8. import javax.servlet.ServletResponse;  
9. import javax.servlet.http.HttpServletRequest;  
10. import javax.servlet.http.HttpServletResponse;  
11.   
12. public class AjaxSessionTimeoutFilter implements Filter {  
13.   
14.     public void destroy() {  
15.   
16.     }  
17.   
18.     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {  
19.         HttpServletRequest req = (HttpServletRequest) request;  
20.         HttpServletResponse res = (HttpServletResponse) response;  
21.         // 判断session里是否有用户信息  
22.         if (req.getSession().getAttribute("SPRING_SECURITY_CONTEXT") == null){  
23.             // 如果是ajax请求响应头会有，x-requested-with；  
24.             if (req.getHeader("x-requested-with") != null && req.getHeader("x-requested-with").equalsIgnoreCase("XMLHttpRequest")){  
25.                 res.setStatus(911);//表示session timeout  
26.             }else{  
27.                 chain.doFilter(req, res);  
28.             }  
29.         }else{  
30.             chain.doFilter(req, res);  
31.         }  
32.     }  
33.   
34.     public void init(FilterConfig chain) throws ServletException {  
35.   
36.     }  
37. }  

2.在web.xml中增加以下配置

[html]  view plain copy

1. <filter>  
2.     <filter-name>ajaxSessionTimeout</filter-name>  
3.     <filter-class>org.tshark.framework.web.filter.AjaxSessionTimeoutFilter</filter-class>  
4. </filter>  
5. <filter-mapping>  
6.     <filter-name>ajaxSessionTimeout</filter-name>  
7.     <url-pattern>/*</url-pattern>  
8. </filter-mapping>  

3.设置Ajax调用全局参数

[javascript]  view plain copy

1. $.ajaxSetup({  
2.     contentType : "application/x-www-form-urlencoded;charset=utf-8",  
3.     complete : function(xhr, textStatus) {  
4.         //session timeout  
5.         if (xhr.status == 911) {  
6.             window.location = "/";//返回应用首页  
7.             return;  
8.         }  
9.     }  
10. });