另一个 spring 拦截器

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

import org.apache.log4j.Logger;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

import com.test.entity.Employee;

/**
* Spring 拦截器
*
* @author jhwen
*
*/
public class SessionInterceptor extends HandlerInterceptorAdapter {
  
    private final Logger logger = Logger.getLogger(SessionInterceptor.class);
  
    /**
     * 在业务处理器处理请求之前被调用
     */
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
            Object handler) throws Exception{
      
        //要排除拦截的请求
        String[] ignoreRegexs = new String[]{"login.do","checkCode.do"};
      
        //获取客户端请求URI
        String requestURI = request.getRequestURI();
      
        //获取客户端请求
        if(null!=requestURI && !"".equals(requestURI)){
            //不同的工程，substring(int paramInt1,int paramInt2)的paramInt1不同
            requestURI = requestURI.substring(8, requestURI.length());
        }
      
        for(int i=0; i<ignoreRegexs.length; i++){
          
            String ignoreRegex = ignoreRegexs[i];
          
            /**
             * 如果是login.do 和 checkCode.do, 则不做拦截
             */
            if(ignoreRegex.equals(requestURI)){
                return true;
            }
        }
      
        /**
         * 如果不是login.do(登录) 和 checkCode.do(检验验证码), 则做拦截，
         * 并且，判断是否已经登录
         */
        Employee emp = (Employee)request.getSession().getAttribute("emp");
      
        /**
         * 如果未登录，则不允许操作；
         * 如果已经登录，则允许做其他的操作.
         */
        if(null == emp){
            return false;
        }else{
            return true;
        }
    }  

}

Spring 的核心配置文件 applicationContext.xml：

<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
     <property name="interceptors">
         <list>
                <bean class="com.test.common.core.interceptor.SessionInterceptor" />
         </list>
     </property>
    </bean>