https://www.heckjj.com/index.php zh-cn https://www.heckjj.com/user-login-validate-filter/ Heck <@hecks.tk> Thu, 09 Sep 2010 17:20:49 +0000 https://www.heckjj.com/user-login-validate-filter/ <filter>     <filter-name>onlineFilter</filter-name>     <filter-class>struts.form.OnlineFilter</filter-class> </filter>    <filter-mapping>     <filter-name>onlineFilter</filter-name>     <url-pattern>*.jsp</url-pattern> </filter-mapping>
Filter的配置：
package struts.form; import java.io.IOException; import javax.servlet.Filter; import javax.servlet.FilterChain; import javax.servlet.FilterConfig; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.*; public class OnlineFilter extends HttpServlet implements Filter { public void init(FilterConfig filterConfig) throws ServletException { } public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {   RequestDispatcher dispatcher = request.getRequestDispatcher("UserLogin.jsp");   HttpServletRequest req = (HttpServletRequest) request;   HttpServletResponse res = (HttpServletResponse) response;   HttpSession session = req.getSession(true);   // 从session里取的用户名信息   String username = (String) session.getAttribute("sessionUserName");   // 判断如果没有取到用户信息,就跳转到登陆页面   if (username == null || "".equals(username))   {    // 跳转到登陆页面    dispatcher.forward(request,response);    System.out.println("用户没有登陆，不允许操作");   }   else   {    // 已经登陆,继续此次请求    chain.doFilter(request,response);    System.out.println("用户已经登陆，允许操作");   } } public void destroy() { } }
Tags - 登陆验证 , 判断用户是否在线 , 判断用户登陆 ]]> https://www.heckjj.com/user-login-validate-filter/#blogcomment <user@domain.com> Thu, 01 Jan 1970 00:00:00 +0000 https://www.heckjj.com/user-login-validate-filter/#blogcomment