Spring MVC过滤器-登录过滤处理 ，访问页面的权限以及是否登陆

package com.wisdom.management.filter;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.FilterChain;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.springframework.web.filter.OncePerRequestFilter;/**   * 类名称：SessionFilter    * 类描述： 登陆过滤器     * 修改备注：    * @version     */ public class SessionFilter extends OncePerRequestFilter {/* * (non-Javadoc) *  * @see * org.springframework.web.filter.OncePerRequestFilter#doFilterInternal( * javax.servlet.http.HttpServletRequest, * javax.servlet.http.HttpServletResponse, javax.servlet.FilterChain) */@Overrideprotected void doFilterInternal(HttpServletRequest request,HttpServletResponse response, FilterChain filterChain)throws ServletException, IOException {// 不过滤的uriString[] notFilter = new String[] { "login.jsp"};// 请求的uriString uri = request.getRequestURI();// uri中包含pages时才进行过滤if (uri.indexOf("article") != -1) {// 是否过滤boolean doFilter = true;for (String s : notFilter) {if (uri.indexOf(s) != -1) {// 如果uri中包含不过滤的uri，则不进行过滤doFilter = false;break;}}if (doFilter) {// 执行过滤// 从session中获取登录者实体Object obj = request.getSession().getAttribute("loginedUser");if (null == obj) {// 如果session中不存在登录者实体，则弹出框提示重新登录// 设置request和response的字符集，防止乱码request.setCharacterEncoding("UTF-8");response.setCharacterEncoding("UTF-8");PrintWriter out = response.getWriter();String loginPage = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+request.getContextPath();StringBuilder builder = new StringBuilder();builder.append("<script charset=\"UTF-8\" language=\"javascript\" type=\"text/javascript\">");builder.append("alert('网页过期，请重新登录！');");builder.append("window.top.location.href='");builder.append(loginPage);builder.append("';");builder.append("</script>");out.print(builder.toString());} else {// 如果session中存在登录者实体，则继续filterChain.doFilter(request, response);}} else {// 如果不执行过滤，则继续filterChain.doFilter(request, response);}} else {// 如果uri中不包含background，则继续filterChain.doFilter(request, response);}}}

2. 写完过滤器后，需要在web.xml中进行配置：

   <!-- 登陆过滤器 -->   <filter><filter-name>sessionFilter</filter-name><filter-class>com.wisdom.management.filter.SessionFilter</filter-class></filter><filter-mapping><filter-name>sessionFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping>