Spring Mvc session拦截器实现

          Spring Mvc拦截器实现session过期跳转到登录页面

• 配置拦截器

    <mvc:interceptors>  
	    <mvc:interceptor>  
	        <mvc:mapping path="/**/*.html"/>  
	        <bean class="com.rrtong.frame.plugins.SecurityInterceptor">
		      <property name="excludedUrls">  
		        <list>  
		          <value>/login.html</value>  
		          <value>/auth.html</value>    
		        </list>  
		      </property>  	       
	        </bean>  
	    </mvc:interceptor>  
	</mvc:interceptors>  

• 实现拦截器

package com.rrtong.frame.plugins;

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;

import com.rrtong.util.Constants;

/*实现登录访问验证拦截器*/
public class SecurityInterceptor implements HandlerInterceptor {
	/*过滤不需要验证的url*/
	private List<String> excludedUrls;  
	
	public void setExcludedUrls(List<String> excludedUrls) {  
	    this.excludedUrls = excludedUrls;  
	}  	
	
	@Override
	public boolean preHandle(HttpServletRequest request,
			HttpServletResponse response, Object handler) throws Exception {
        String requestUri = request.getRequestURI();    
        
        for (String url : excludedUrls) {  
        	if (requestUri.endsWith(url)) {  
        		return true;  
        	}  
        }          
        		
        /*判断是否需要过滤的页面*/
        HttpSession session = request.getSession();  
        
        if(session.getAttribute(Constants.Session.CURRENT_USER_ATTR_NAME) == null){
        	/*跳转到登录页*/
        	request.getRequestDispatcher("/WEB-INF/jsp/login.jsp").forward(request, response);
        	
        	return false;
        }
        return true;
	}

	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response,
			Object arg2, ModelAndView arg3) throws Exception {
	}

	@Override
	public void afterCompletion(HttpServletRequest request,
			HttpServletResponse response, Object arg2, Exception arg3)
			throws Exception {
	}		
}