Spring mvc Interceptor 解决Session超时跳转

Spring mvc Interceptor 解决Session超时

1：在spring_xxx.xml里加入相关配置

<mvc:interceptors><mvc:interceptor><mvc:mapping path="/*/*" /><bean class="com.teachmanage.mvc.interceptor.SessionTimeoutInterceptor" ><property name="allowUrls">        <list>          <value>/login</value>          <value>/login/logout</value>        </list>     </property>    </bean></mvc:interceptor></mvc:interceptors><!-- exception handler --><bean id="handlerExceptionResolver" class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver" ><property name="exceptionMappings"><props><prop key="com.teachmanage.mvc.exception.SessionTimeoutException">redirect:/login</prop></props></property></bean>

上述配置里，list中的url为允许访问的url，即从这些url访问的话，不需要判断session是否超时。（为什么这些url能够不判断，是在下述拦截器代码里实现的。）

拦截生效后，会抛出SessionTimeoutException，跳转到/login。这里的redirect:/login是指controller里对应的url，如果想跳转到login.jsp，则直接/login。

2：创建SessionTimeoutInterceptor

public class SessionTimeoutInterceptor implements HandlerInterceptor   {private List<String> allowUrls = new ArrayList<String>();public List<String> getAllowUrls() {return allowUrls;}public void setAllowUrls(List<String> allowUrls) {this.allowUrls = allowUrls;}public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {String requestUrl = request.getRequestURI();for(String url : allowUrls) {if(requestUrl.endsWith(url)) {return true;}}String session = TypeConvertCommon.toString(WebUtils.getSessionAttribute(request, "User_id"));if("".equals(session)) {throw new SessionTimeoutException();} else {return true;}}@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {}@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {}}

该拦截器需要实现HandlerInterceptor接口，否则会报错No matching editors or conversion strategy found。不过postHandle和afterComletion暂时无事可做，空着就可以了。

还需要创建一个SessionTimeoutException类，不过不需要写入代码，空着就行。

3：如果项目使用了iframe，则超时跳转时会造成登陆页面内嵌到当前页面，可以在登陆画面上加上如下js代码：

if (window != top) {top.location.href = location.href;}