springMVC 拦截器 登录管理

一、web.xml

	<servlet>
		<servlet-name>spring-mvc</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath:spring/spring-mvc.xml</param-value>
		</init-param>
		<load-on-startup>1</load-on-startup>
	</servlet>

二、springmvc.xml

	<mvc:interceptors>  
    	<!-- 使用bean定义一个Interceptor，直接定义在mvc:interceptors根下面的Interceptor将拦截所有的请求 -->  
	    <!-- <bean class="cn.picclife.mwx.activity.util.AuthInterceptor"/> --> 
	    <!-- 拦截器配置项  -->
	    <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="/customer_insert_reg"/>
	        
	       	<!-- 不被拦截范围（路径）；例如：后台登录页面 -->
			<mvc:exclude-mapping path="/agent_login"/>
			
	        <!-- 定义在mvc:interceptor下面的表示是对特定的请求才进行拦截的 -->
	        <bean class="cn.picclife.mwx.activity.util.LoginInterceptor"/>
	    </mvc:interceptor>  
	</mvc:interceptors> 

三、java类

import java.io.PrintWriter;

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

import org.apache.commons.lang3.StringUtils;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;



/**
 * 
 * @ClassName: AuthInterceptor
 * @Description: 登陆判断
 * @date 2016年11月9日 下午8:05:10
 *
 */
public class LoginInterceptor extends HandlerInterceptorAdapter {
	// 登陆页面
	private static final String loginPage = "/public/agent_login.html";
	// 微信绑定页
	// private static final String wxBindingPage = "/user/wxbind.jhtml";

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

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

	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object obj) throws Exception {
		request.setCharacterEncoding("UTF-8");
		response.setCharacterEncoding("UTF-8");
		response.setContentType("text/html;charset=UTF-8");
		// session管理和登陆判断
		Boolean isLogin = false;
		
		Agent agent = (Agent) request.getSession().getAttribute("Agent");
		if (agent != null) {
			isLogin = true;
		}
		String openId = (String) request.getSession().getAttribute("openId");
		// String openId = "oO6scvxfO0py5wFlHTRTI8J0JLyc";
		if (!isLogin) {
			String requestType = request.getHeader("x-requested-with");
			boolean isAjax = false;
			if ("XMLHttpRequest".equals(requestType)) {
				isAjax = true;
			}
			// 判断是否是ajax请求
			if (isAjax) {
				PrintWriter out = response.getWriter();
				out.print("{\"code\":\"20000\",\"msg\":\"用户尚未登陆\"}");
				out.flush();
				out.close();
			} else {
				String ctx = request.getContextPath();
				if (StringUtils.isBlank(openId)) {
					// 未登录
					PrintWriter out = response.getWriter();
					StringBuilder builder = new StringBuilder();
					builder.append("<script type=\"text/javascript\" charset=\"UTF-8\">");
					builder.append("alert(\"页面过期，请重新登录\");");
					builder.append("window.top.location.href=\"");
					builder.append(ctx + loginPage);
					builder.append("\";");
					builder.append("</script>");
					out.print(builder.toString());
					out.close();
				} else {
					response.sendRedirect(ctx + loginPage);
				}
			}
			return false;
		}
		return true;
	}
}