过滤器的使用（权限过滤器）
Posted 初夏的一棵歪脖子树
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了过滤器的使用（权限过滤器）相关的知识，希望对你有一定的参考价值。
1.实体类
1 package com.zdsofe.work; 2 3 public class User { 4 5 6 public String userName; 7 public String password; 8 9 public User(String userName, String password) { 10 11 this.userName = userName; 12 this.password = password; 13 } 14 public String getUserName() { 15 return userName; 16 } 17 public void setUserName(String userName) { 18 this.userName = userName; 19 } 20 public String getPassword() { 21 return password; 22 } 23 public void setPassword(String password) { 24 this.password = password; 25 } 26 }
2.web.xml的配置
1 <?xml version="1.0" encoding="UTF-8"?> 2 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"> 3 <display-name>webProject4</display-name> 4 <filter> 5 <filter-name>code</filter-name> 6 <filter-class>com.zdsofe.work.UserFliter</filter-class> 7 </filter> 8 <filter-mapping> 9 <filter-name>code</filter-name> 10 <url-pattern>/pages/*</url-pattern> 11 </filter-mapping> 12 <welcome-file-list> 13 <welcome-file>index.html</welcome-file> 14 <welcome-file>index.htm</welcome-file> 15 <welcome-file>index.jsp</welcome-file> 16 <welcome-file>default.html</welcome-file> 17 <welcome-file>default.htm</welcome-file> 18 <welcome-file>default.jsp</welcome-file> 19 </welcome-file-list> 20 </web-app>
3.主页面
1 <%@ page language="java" contentType="text/html; charset=UTF-8" 2 pageEncoding="UTF-8"%> 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 4 <html> 5 <head> 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 7 <title>Insert title here</title> 8 </head> 9 10 <body> 11 <form action="loginServlet"> 12 用户名：<input type="text" name="userName"/><br/> 13 密码：<input type="password" name="password"/><br/> 14 <button type="submit">登录</button> 15 </form> 16 </body> 17 </html>
4.登录成功页面
1 <%@ page language="java" contentType="text/html; charset=UTF-8" 2 pageEncoding="UTF-8"%> 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 4 <html> 5 <head> 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 7 <title>Insert title here</title> 8 </head> 9 <body> 10 <h1>欢迎您！！！</h1> 11 </body> 12 </html>
5.过滤器
1 package com.zdsofe.work; 2 3 import java.io.IOException; 4 5 import javax.servlet.Filter; 6 import javax.servlet.FilterChain; 7 import javax.servlet.FilterConfig; 8 import javax.servlet.ServletException; 9 import javax.servlet.ServletRequest; 10 import javax.servlet.ServletResponse; 11 import javax.servlet.http.HttpServletRequest; 12 import javax.servlet.http.HttpServletResponse; 13 14 import org.apache.commons.lang.StringUtils; 15 16 17 18 public class UserFliter implements Filter { 19 20 @Override 21 public void destroy() { 22 // TODO Auto-generated method stub 23 24 } 25 26 @Override 27 public void doFilter(ServletRequest arg0, ServletResponse arg1, 28 FilterChain arg2) throws IOException, ServletException { 29 /*//过滤器 30 HttpServletRequest request=(HttpServletRequest)arg0; 31 HttpServletResponse response=( HttpServletResponse)arg1; 32 request.setCharacterEncoding("utf-8"); 33 response.setCharacterEncoding("utf-8"); 34 response.setContentType("text/html charset=utf-8"); 35 arg2.doFilter(arg0, arg1);*/ 36 37 //权限验证过滤器 38 HttpServletRequest request=(HttpServletRequest)arg0; 39 HttpServletResponse response=( HttpServletResponse)arg1; 40 User user= (User)request.getSession().getAttribute("user"); 41 42 43 if(null!=user) 44 { 45 String userName=user.getUserName(); 46 if(StringUtils.isNotBlank(userName)&&userName.contains("admin")) 47 { 48 System.out.println("登录成功"); 49 arg2.doFilter(request, response); 50 } else 51 { 52 response.sendRedirect(request.getContextPath()+"/login.jsp"); 53 } 54 }else 55 { 56 response.sendRedirect(request.getContextPath()+"/login.jsp"); 57 } 58 59 } 60 61 @Override 62 public void init(FilterConfig arg0) throws ServletException { 63 64 } 65 66 }
6.服务器
1 package com.zdsofe.work; 2 3 import java.io.IOException; 4 5 import javax.servlet.ServletException; 6 import javax.servlet.annotation.WebServlet; 7 import javax.servlet.http.HttpServlet; 8 import javax.servlet.http.HttpServletRequest; 9 import javax.servlet.http.HttpServletResponse; 10 import javax.servlet.http.HttpSession; 11 12 13 14 /** 15 * Servlet implementation class loginServlet 16 */ 17 @WebServlet("/loginServlet") 18 public class loginServlet extends HttpServlet { 19 private static final long serialVersionUID = 1L; 20 21 /** 22 * @see HttpServlet#HttpServlet() 23 */ 24 public loginServlet() { 25 super(); 26 // TODO Auto-generated constructor stub 27 } 28 29 /** 30 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) 31 */ 32 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 33 /*String name=request.getParameter("userName"); 34 response.getWriter().print(name);*/ 35 36 //获取用户名 37 String userName=request.getParameter("userName"); 38 //获取密码 39 String password=request.getParameter("password"); 40 //创建用户对象 41 User user=new User(userName,password); 42 //创建session对象 43 HttpSession session=request.getSession(true); 44 session.setAttribute("user", user); 45 response.sendRedirect(request.getContextPath()+"/pages/login1.jsp"); 46 } 47 48 /** 49 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) 50 */ 51 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 52 // TODO Auto-generated method stub 53 } 54 55 }
注意：主页面login.jsp直接在webcontent下，登陆成功页面在webcontent的子目录pages下，防止方法重定向死循环。
以上是关于过滤器的使用（权限过滤器）的主要内容，如果未能解决你的问题，请参考以下文章