1.写一个类实现HandlerInterceptor接口
package com.spring.intercepter; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.servlet.HandlerInterceptor; import org.springframework.web.servlet.ModelAndView; public class LoginIntercepter implements HandlerInterceptor { public void afterCompletion(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3) throws Exception { System.out.println("afterCompletion"); } public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3) throws Exception { System.out.println("postHandle"); //可以通过ModelAndView参数来改变显示的视图,或修改发往视图的方法 arg3.setViewName("home"); arg3.addObject("msg", "这是返回的数据！"); } /* * 返回值 * true 请求继续 * false 请求终止 * arg2 被拦截的请求的目标对象 */ public boolean preHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2) throws Exception { System.out.println("preHandle"); //为请求设置编码 arg0.setCharacterEncoding("utf-8"); //对用户是否登录进行判断 if(arg0.getSession().getAttribute("user") == null){ arg0.getRequestDispatcher("login.jsp").forward(arg0, arg1); return false; } return true; } }2。在spring配置文件注册
<mvc:interceptors> <mvc:interceptor> <mvc:mapping path="/**"></mvc:mapping> <bean class="com.spring.intercepter.LoginIntercepter"</bean> </mvc:interceptor> </mvc:interceptors>