拦截器:

package sy.Interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

public class MyInterceptor implements HandlerInterceptor {
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object object) throws Exception {
        System.out.println("preHandle");
        return true;
    }

    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object object, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle");
    }

    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object object, Exception exception) throws Exception {
        System.out.println("afterCompletion");

    }
}

在spring mvc配置文件中配置拦截器:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans 
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd 
http://www.springframework.org/schema/context 
http://www.springframework.org/schema/context/spring-context-3.0.xsd 
http://www.springframework.org/schema/mvc 
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
    <!-- 自动扫描controller包下的所有类,使其认为spring mvc的控制器 -->
    <context:component-scan base-package="sy.controller" />
  <!-- 配置拦截器 -->
    <mvc:interceptors>
        <mvc:interceptor>
            <!-- 匹配的是url路径, 如果不配置或/**,将拦截所有的Controller -->
            <mvc:mapping path="/**" />
            <bean class="sy.Interceptor.MyInterceptor"></bean>
        </mvc:interceptor>
    </mvc:interceptors>

    <!-- JSON映射 解决中文乱码问题 -->
    <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
        <property name="supportedMediaTypes">
            <list>
                <value>text/html;charset=UTF-8</value>
            </list>
        </property>
    </bean>

    <!-- 启动Spring MVC的注解功能,完成请求和注解POJO的映射 -->
    <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <ref bean="mappingJacksonHttpMessageConverter" /><!-- json转换器 -->
            </list>
        </property>
    </bean>

    <!-- 对模型视图名称的解析,即在模型视图名称添加前后缀 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" p:prefix="/WEB-INF/pages/" p:suffix=".jsp" />

    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding">
            <value>UTF-8</value>
        </property>
        <property name="maxUploadSize">
            <value>32505856</value><!-- 上传文件大小限制为31M,31*1024*1024 -->
        </property>
        <property name="maxInMemorySize">
            <value>4096</value>
        </property>
    </bean>

</beans>