springmvc拦截器

1.定义拦截器

package com.lx.interceptor;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.lx.utils.RequestUtil;public class LoginInterceptor implements HandlerInterceptor {    private List<String> excludeUrls;public List<String> getExcludeUrls() {return excludeUrls;}public void setExcludeUrls(List<String> excludeUrls) {this.excludeUrls = excludeUrls;}public void afterCompletion(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3)throws Exception {// TODO Auto-generated method stub}public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3)throws Exception {// TODO Auto-generated method stub}public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {// TODO Auto-generated method stub// 设置字符编码request.setCharacterEncoding("UTF-8");// 判断是否登录(只拦截前台登录)HttpSession session = request.getSession();String requestUrl = RequestUtil.getRequestPath(request);for (String excludeUrl : excludeUrls) {if (requestUrl.indexOf(excludeUrl) != -1) {return true;}}String s=(String) session.getAttribute("123");System.out.println(s);if("123".equals(s)) {System.out.println("session tong______");return true;}response.sendRedirect(request.getContextPath() + "/login.jsp");return false;}}

2、在spring-mvc.xml中配置

<mvc:interceptors>
   <bean class="com.lx.interceptor.LoginInterceptor">
<property name="excludeUrls">
<list>
<value>/login</value>
</list>
</property>
</bean>
</mvc:interceptors>

3、RequestUtil中的内容

package com.lx.utils;import javax.servlet.http.HttpServletRequest;public class RequestUtil {public static String getRequestPath(HttpServletRequest request) {String requestPath = request.getRequestURI();requestPath = requestPath.substring(request.getContextPath().length());// 鍘绘帀椤圭洰璺緞return requestPath;}private static final String[] PROXY_REMOTE_IP_ADDRESS = { "X-Forwarded-For", "X-Real-IP" };public static String getRemoteIp( HttpServletRequest request ) {    for ( int i = 0 ; i < PROXY_REMOTE_IP_ADDRESS.length ; i++ ) {        String ip = request.getHeader( PROXY_REMOTE_IP_ADDRESS[i] );        if ( ip != null && ip.trim().length() > 0 ) {            return getRemoteIpFromForward( ip.trim() );        }    }    return request.getRemoteHost();} private static String getRemoteIpFromForward( String xforwardIp ) {    int commaOffset = xforwardIp.indexOf( ',' );    if ( commaOffset < 0 ) {        return xforwardIp;    }    return xforwardIp.substring( 0 , commaOffset );}}