以下实现登录窗口 Login.jsp
<!--Login.jsp--> <%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <head> <title>登录页面</title> </head> <body bgcolor="cccfff"> <form action="Check" method="post"> <table> <tr><td>用户</td><td><input type="text"name="user"></td></tr> <tr><td>密码</td><td><input type="password"name="password"></td></tr> <tr align="center"> <td colspan="2"> <input type="submit"value="登 录"> <input type="reset"value="取 消 "> </td> </tr> </table> </form> </body> </html>
处理登录的Servlet
package ch04;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class Check extends HttpServlet {
/**
* Constructor of the object.
*/
public Check() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
/*
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the GET method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
*/
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String name=request.getParameter("user");//获取用户名
String password=request.getParameter("password");//获取密码
if(("client".equals(name))&&"123456".equals(password)){//设置用户名和密码
//如果用户名和密码相对应，则跳转到学生体质管理页面
RequestDispatcher rd=request.getRequestDispatcher("success.jsp");
rd.forward(request, response);
}else{//账户名或密码不正确则跳转登录失败页面
RequestDispatcher rd=request.getRequestDispatcher("Faile.jsp");
rd.forward(request, response);
}
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
登录成功页面success.jsp
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<html>
<head> <title>成功页面</title> </head>
<body>
<%String Name=request.getParameter("user"); %>
欢迎，<%=Name %>成功登陆！
</body>
</html>
登录失败页面Faile.jsp
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<html>
<head> <title>失败页面</title> </head>
<body>
登陆失败！
<!--获取用户名 -->
<%String Name=request.getParameter("user"); %>
<!--重新跳转到登陆页面 -->
<br><a href="Login.jsp">请重新登录，<%=Name %>同学！
</body>
</html>
配置文件，在web.xml中，添加Check的配置信息，
（注意jsp页面调用Servlet的方法）
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0"
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_3_0.xsd">
<servlet>
<servlet-name>Check</servlet-name>
<servlet-class>ch04.Check</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Check</servlet-name>
<url-pattern>/Check</url-pattern>
</servlet-mapping>
</web-app>