一个关于页面访问授权的filter

filter文件：

import java.io.IOException;import javax.servlet.Filter;import javax.servlet.FilterChain;import javax.servlet.FilterConfig;import javax.servlet.ServletException;import javax.servlet.ServletRequest;import javax.servlet.ServletResponse;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;public class FilterAccess implements Filter { public void init(FilterConfig filterConfig) throws ServletException {} public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)throws IOException, ServletException { HttpServletRequest hreq = (HttpServletRequest)request; HttpServletResponse hres = (HttpServletResponse)response; HttpSession session = ((HttpServletRequest)hreq).getSession(); String username = (String)session.getAttribute("username"); if(username == null) { //首页网址 hres.sendRedirect("http://localhost:8080" + hreq.getContextPath() + "/index.jsp"); } else { chain.doFilter(request, response); } } public void destroy() {}}

 

web.xml文件：

<?xml version="1.0" encoding="UTF-8"?><web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" > <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <filter> <filter-name>setEncoding</filter-name> <filter-class>cn.edu.sjzri.filterEncoding.FilterEncoding</filter-class> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> <filter-name>accessControl</filter-name> <!--cn.edu.sjzri.filterEncoding包名不太规范--> <filter-class>cn.edu.sjzri.filterEncoding.FilterAccess</filter-class> </filter> <filter-mapping> <filter-name>setEncoding</filter-name> <url-pattern>/*</url-pattern> <filter-name>accessControl</filter-name> <url-pattern>/admin/*</url-pattern> </filter-mapping> <!-- Standard Action Servlet Configuration --> <servlet> <servlet-name>action</servlet-name> <servlet-class>org.apache.struts.action.ActionServlet</servlet-class> <init-param> <param-name>config</param-name> <param-value>/WEB-INF/struts-config.xml</param-value> </init-param> <load-on-startup>2</load-on-startup> </servlet> <!-- Standard Action Servlet Mapping --> <servlet-mapping> <servlet-name>action</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping></web-app>