Filter

public class CustomFilter implements javax.servlet.Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        //before
        chain.doFilter(request, response);
       //after
    }

    @Override
    public void destroy() {

    }


}

Interceptor

import org.springframework.web.servlet.HandlerInterceptor;
//第一种 实现接口
public class CustomInterceptor implements HandlerInterceptor {

    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)throws Exception {
        return false;
    }

    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
            ModelAndView modelAndView) throws Exception {
    }

    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
    }

}

import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
//第二种继承Adaptor
public class CustomInterceptor2 extends HandlerInterceptorAdapter {

}

interceptor配置

<mvc:interceptors>  
    <!-- 使用bean定义一个Interceptor，直接定义在mvc:interceptors根下面的Interceptor将拦截所有的请求 -->  
    <bean class="com.host.app.web.interceptor.AllInterceptor"/>  
    <mvc:interceptor>  
        <mvc:mapping path="/test/number.do"/>  
        <!-- 定义在mvc:interceptor下面的表示是对特定的请求才进行拦截的 -->  
        <bean class="com.host.app.web.interceptor.LoginInterceptor"/>  
    </mvc:interceptor>  
</mvc:interceptors>  

执行顺序

Filter.doFilter -->Filter.chain.doFilter() --> Interceptor.preHandle-->

Controller.execute-->

Interceptor.postHandle-->Controller.response-->

Interceptor.afterCompletion-->Filter.chain.doFilter() after;