过滤器拦截类
package com.ssm.filter; import org.omg.PortableServer.SERVANT_RETENTION_POLICY_ID; import javax.servlet.*; import javax.servlet.annotation.WebFilter; import javax.servlet.http.HttpServletRequest; import java.io.IOException; @WebFilter(urlPatterns = {"/*"}) public class myFilter implements Filter { @Override public void init(FilterConfig filterConfig) throws ServletException { } @Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException { HttpServletRequest httpServletRequest=(HttpServletRequest) servletRequest; System.out.println(httpServletRequest.getRequestURI()); if(httpServletRequest.getRequestURI().equals("/user/login")){ filterChain.doFilter(servletRequest,servletResponse); System.out.println("合法请求"); } Object user = httpServletRequest.getSession().getAttribute("user"); if(user==null){ System.out.println("非法请求"); httpServletRequest.getRequestDispatcher("/login.jsp").forward(servletRequest,servletResponse); }else{ filterChain.doFilter(servletRequest,servletResponse); } } @Override public void destroy() { } }
web.xml文件配置
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd" > <web-app> <display-name>Archetype Created Web Application</display-name> <filter> <filter-name>characterEncodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <!--初始化参数--> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> <!--强制使用UTF-8编码--> <init-param> <param-name>forceEncoding</param-name> <param-value>true</param-value> </init-param> </filter> <filter-mapping> <filter-name>characterEncodingFilter</filter-name> <url-pattern>/</url-pattern> </filter-mapping> <!--中央调度器--> <servlet> <servlet-name>springmvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>
login.jsp页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登陆</title> </head> <body> <div> <form action="/user/login" method="post"> 用户名：<input type="text" name="usercode"/> 密码：<input type="password" name="userpassword"/> <input type="submit" value="登陆"/> </form> </div> </body> </html>
welcome.jsp页面
<%-- Created by IntelliJ IDEA. User: FLC Date: 2019/11/14 Time: 10:00 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %> <html> <head> <title>欢迎</title> </head> <body> 欢迎光临：${user.username} </body> </html>
在没有登录的情况下访问首页，则直接跳转到登录页面，进行登录验证；
