06-SrpingMVC拦截器快速入门

执行顺序：preHandle -> 目标方法（类似Controller层里的）-> postHandle ->afterCompletion

public class MyInterceptor1 implements HandlerInterceptor {
    //在目标方法执行之前执行
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("preHandle......");
        //如果为false后边都不执行
        return false;
    }

    //在目标方法执行之后 视图返回之前执行
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle......");
    }

    //在整个流程都执行完毕之后执行
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("afterCompletion");
    }
}