spring mvc 拦截器

拦截器作用：可以用于用户操作的安全检查，如：登录、权限等

package com.tool;

import java.util.List;

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

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

public class SecurityInterceptor implements HandlerInterceptor {
    private List<String> excludedUrls;

    public void setExcludedUrls(List<String> excludedUrls) {
        this.excludedUrls = excludedUrls;
    }

    @Override
    public void afterCompletion(HttpServletRequest arg0,
            HttpServletResponse arg1, Object arg2, Exception arg3)
            throws Exception {

    }

    @Override
    public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1,
            Object arg2, ModelAndView arg3) throws Exception {

    }

    @Override
    public boolean preHandle(HttpServletRequest request,
            HttpServletResponse arg1, Object arg2) throws Exception {
        String requestUri = request.getRequestURI();
        if (excludedUrls == null || excludedUrls.size() == 0)
            return true;        
        for (String url : excludedUrls) {
            if (requestUri.endsWith(url)) {
                return true;
            }
        }
        //这里可以判断用记是否登录、用户权限
        HttpSession session = request.getSession();        
        if (session.getAttribute("user") == null) {
            throw new Exception("我是来自拦截器的方法");
        } else {
            return true;
        }
    }
}

mvc配置

    <!--定义拦截器，验证登录，验证权限都可以在这里玩耍了-->
    <mvc:interceptors>
        <mvc:interceptor>
            <mvc:mapping path="/**" />
            <bean class="com.tool.SecurityInterceptor">
                <!--定义不需要拦截的url集合-->
                <property name="excludedUrls">
                    <list>
                        <!--                        <value>/HelloWorld/myhello.do</value>-->
                    </list>
                </property>
            </bean>
        </mvc:interceptor>
    </mvc:interceptors>