1、目的：拦截器的配置主要是对请求进行相应的处理（在登录和session过时的时候是一个很好的方式）
2、由于Spring容器的优越性，在配置的时候全部交给容器管理是一个很不错的方式
3、配置拦截器：
1）在对应的方式类中实现HandlerInterceptor接口，会要求实现3个方法
@Override
public void afterCompletion(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3)
throws Exception {
// TODO Auto-generated method stub
}
@Override
public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3)
throws Exception {
// TODO Auto-generated method stub
}
public boolean preHandle(HttpServletRequest request, HttpServletResponse response,Object obj) throws Exception {
return true;
}
2）所有的请求都会在拦截器里面经过，这样在做登录拦截的时候会起到数据的保护和相关的展示限权
在preHandle方法里面加入自己的逻辑
public boolean preHandle(HttpServletRequest request, HttpServletResponse response,Object obj) throws Exception {
//获取判定登陆的session是否存在
String token = (String) request.getSession().getAttribute("token");
String postId = (String) request.getSession().getAttribute("postId");
if(token == null || token == ""){
String XRequested =request.getHeader("X-Requested-With");
if("XMLHttpRequest".equals(XRequested)){
response.getWriter().write("IsAjax");
}else{
response.sendRedirect("/m-web/");
}
return false;
}
if(postId == null || postId == ""){
String XRequested =request.getHeader("X-Requested-With");
if("XMLHttpRequest".equals(XRequested)){
response.getWriter().write("IsAjax");
}else{
response.sendRedirect("/m-web/");
}
return false;
}
return true;
}
里面存在ajax请求拦截的处理详情见：http://www.cnblogs.com/ll409546297/p/6203403.html
3、在Spring的配置文件里面加入
<mvc:interceptors> <mvc:interceptor> <mvc:mapping path="/**"/> <mvc:exclude-mapping path="/user/login"/> <mvc:exclude-mapping path="/user/loginOut"/> <mvc:exclude-mapping path="/user/setPostId"/> <mvc:exclude-mapping path="/user/getPostId"/> <mvc:exclude-mapping path="/resources/**"/> <mvc:exclude-mapping path="/assets/**"/> <mvc:exclude-mapping path="/css/**"/> <mvc:exclude-mapping path="/fonts/**"/> <mvc:exclude-mapping path="/images/**"/> <mvc:exclude-mapping path="/img/**"/> <mvc:exclude-mapping path="/js/**"/> <mvc:exclude-mapping path="/pic/**"/> <mvc:exclude-mapping path="/plugins/**"/> <mvc:exclude-mapping path="/static/**"/> <mvc:exclude-mapping path="/ui/**"/> <bean class="com.troy.ai.web.Interceptors.LoginInterceptor"/> </mvc:interceptor> </mvc:interceptors>
解释：
<mvc:mapping path="/**"/> //是对所有路径进行过滤 <mvc:exclude-mapping path="/user/login"/> //是对该路径进行放行 <mvc:exclude-mapping path="/ui/**"/> //是对静态资源加载放行 <bean class="com.troy.ai.web.Interceptors.LoginInterceptor"/> //指定处理拦截的相关类
4、拦截器的配置相对简单，但是在实际的应用过程却非常常见，逻辑处理方面需要根据实际来处理