jap 登陆模块的实现

使用MVC设计模式 此登录模块至少分为以下5个文件： 1.login.jsp:输入用户信息页面； 2.check.mgc(Servlet):用户合法性验证页面； 3.pass.jsp:登录成功欢迎页面； 4.failure.jsp:登录失败提示页面； 5.Member(JavaBean):VO对象类。

结构图如下： -----------------------------------------------------------------------

         -------------> login.jsp          |                       |          |                       |输入用户名、密码          |                       V          |                  check.mgc<------------->Member          |                       |          |                       |验证用户名、密码          |          ----------------------          |          | N                   Y |          |          V                        V          -----failure.jsp           pass.jsp -----------------------------------------------------------------------

Member:

 程序代码

package mgc.bean.mvc.login;

public class Member {

    private String username;     private String password;         public void setUsername(String username) {         this.username=username;     }         public void setPassword(String password) {         this.password=password;     }         public String getUsername() {         return this.username;     }         public String getPassword() {         return this.password;     }         //验证用户是否合法     public boolean isUser() {         boolean isuser=false;         if("magci".equals(this.username) && "123456".equals(this.password)) {             //如果用户名为magci，密码为123456，则用户合法             isuser=true;         }         return isuser;     } }

 

login.jsp:

 程序代码

<%@page contentType="text/html;charset=GB2312" %> <html>   <head>     <title>登录</title>   </head>     <body>       <center>       <h1>登录页面</h1>       <hr>     <form action="check.mgc" method="post">         <table>             <tr>                 <td>用户名：</td>                 <td><input type="text" name="username" /></td>             </tr>             <tr>                 <td>密  码：</td>                 <td><input type="password" name="password" /></td>             </tr>             <tr>                 <td colspan="2" align="center">                     <input type="submit" value="登录" />                     <input type="reset" value="重置" />                 </td>             </tr>         </table>     </form>     </center>   </body> </html>

 

check.java:

 程序代码

package mgc.servlet.mvc.login;

import java.io.*; import javax.servlet.*; import javax.servlet.http.*; import mgc.bean.mvc.login.*;

public class Check extends HttpServlet {         public void doGet(HttpServletRequest request,HttpServletResponse response) throws IOException,ServletException {                 this.doPost(request,response);     }         public void doPost(HttpServletRequest request,HttpServletResponse response) throws IOException,ServletException {                 Member mem=new Member();         //将提交的用户名、密码参数设置到Member对象中         mem.setUsername(request.getParameter("username"));         mem.setPassword(request.getParameter("password"));         //调用方法验证用户是否合法         if(mem.isUser()) {             //合法用户，跳转到欢迎页面             request.getRequestDispatcher("pass.jsp").forward(request, response);         }         else {             //非法用户，跳转到登录失败页面             request.getRequestDispatcher("failure.jsp").forward(request, response);         }     } }

 

web.xml:

 程序代码

  <servlet>     <servlet-name>Check</servlet-name>     <servlet-class>mgc.servlet.mvc.login.Check</servlet-class>   </servlet>

  <servlet-mapping>     <servlet-name>Check</servlet-name>     <url-pattern>/login/mvcbase/check.mgc</url-pattern>   </servlet-mapping>

 

pass.jsp:

 程序代码

<%@page contentType="text/html;charset=GB2312" %> <center>     <h1>登录成功!!</h1>     <hr>     <h3>欢迎<font size="12" color="red">     <%--服务器端跳转，跳转后仍在check.mgc页面，可以继续使用usename参数 --%>     <%=request.getParameter("username") %>     </font>光临！</h3> </center>

 

failure.jsp:

 程序代码

<%@page contentType="text/html;charset=GB2312" %> <div align="center"> <h1>登录失败!!</h1> <hr> <a href="login.jsp">重新登录</a> </div>