2层架构,JSP+Servlet
login.jsp
<%@ page language="java" contentType="text/html; charset=GBK" pageEncoding="GBK"%> <HTML> <HEAD> <TITLE>2层架构</TITLE> </HEAD> <BODY> <span id="tips"></span> <form name="loginForm" action="doLogin" method="post"> 用户名:<input type="text" id="username" name="username"> 密码:<input type="password" id="password" name="password"> <hr> <input type="button" value="提交" onclick="ok()"> </form> </BODY> <script language="javascript"> function ok(){ var username = document.getElementById("username").value; var password = document.getElementById("password").value; if(username == "" || password == ""){ // alert("用户名或密码不能为空!"); document.getElementById("tips").innerHTML="<font color='red'>用户名或密码不能为空!</font>"; }else{ document.loginForm.submit(); } } </script> </HTML>
web.xml
<?xml version="1.0" encoding="ISO-8859-1"?> <web-app 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_2_5.xsd" version="2.5"> <servlet> <servlet-name>DoLoginServlet</servlet-name> <servlet-class>control.DoLoginServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>DoLoginServlet</servlet-name>
<!--<url-pattern>的值必须以/开头-->
<url-pattern>/doLogin</url-pattern> </servlet-mapping> </web-app>
control.DoLoginServlet.java
package control; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class DoLoginServlet extends HttpServlet { private static final long serialVersionUID = 1L; @Override protected void service(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { String encoding = "GBK"; request.setCharacterEncoding(encoding); response.setCharacterEncoding(encoding); String userName = request.getParameter("username"); String password = request.getParameter("password"); if("黄启庆".equals(userName) && "123456".equals(password)){ request.getRequestDispatcher("success.jsp").forward(request, response); }else{ request.getRequestDispatcher("fail.jsp").forward(request, response); } } }