一個完整的簡單jsp+servlet例項，實現簡單的登入
1、先建立web project，專案名為RegisterSystem，
2、在WebRoot 目錄下建立login.jsp檔案：
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>My JSP 'login.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> This is my JSP page. <br> <form action="login"> username:<input type="text" name="username"><br> password:<input type="password" name="pwd"><br> <input type="submit"> </form> </body> </html>
3、在scr目錄下的com.ht.servlet編寫AccountBean.java檔案，程式碼如下：
package com.ht.servlet;
public class AccountBean {
private String username;
private String password;
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
}
4、在scr目錄下的com.ht.servlet編寫servlet類CheckAccount.java檔案，程式碼如下：
package com.ht.servlet;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
public class CheckAccount extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
doGet(req,resp);
}
@Override
public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
HttpSession session = req.getSession();
AccountBean account = new AccountBean();
String username = req.getParameter("username");
String pwd = req.getParameter("pwd");
account.setPassword(pwd);
account.setUsername(username);
if((username != null)&&(username.trim().equals("jsp"))) {
if((pwd != null)&&(pwd.trim().equals("1"))) {
System.out.println("success");
session.setAttribute("account", account);
String login_suc = "success.jsp";
resp.sendRedirect(login_suc);
return;
}
}
String login_fail = "fail.jsp";
resp.sendRedirect(login_fail);
return;
}
}
5、在WebRoot目錄下編寫success.jsp檔案 成功後跳轉
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@page import="com.ht.servlet.AccountBean"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'success.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<%
AccountBean account = (AccountBean)session.getAttribute("account");
%>
username:<%= account.getUsername()%>
<br>
password:<%= account.getPassword() %>
basePath: <%=basePath%>
path:<%=path%>
</body>
</html>
6、在WebRoot目錄下編寫fail.jsp檔案 失敗後跳轉
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'fail.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
Login Failed! <br>
basePath: <%=basePath%>
path:<%=path%>
</body>
</html>
7、修改web.xml配置檔案
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
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">
<welcome-file-list>
<welcome-file>login.jsp</welcome-file>
</welcome-file-list>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>CheckAccount</servlet-name>
<servlet-class>com.ht.servlet.CheckAccount</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>CheckAccount</servlet-name>
<url-pattern>/login</url-pattern>
</servlet-mapping>
</web-app>
輸入測試路徑：http://localhost:8080/RegisterSystem/login.jsp
注意：
.處理中文亂碼問題
在Sertlet中加
response.setContentType("text/html;charset=utf-8")
在jsp頁面中加
<%@ page language="java" import="java.util.*,java.net.URLEncoder" pageEncoding="UTF-8"%>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
在servlet中
String username=request.getParameter("username");
username=new String(username.getBytes(“ISO-8859-1”),"UTF-8");
reference ：http://blog.sina.com.cn/s/blog_5c5bc9070100z7wb.html
http://lelglin.iteye.com/blog/967503
http://zhidao.baidu.com/link?url=qg1AcsUjhkG4gHBv8GtHDjIQuwgtLto1_eyeinBx-b8TW9HAcYRR1zizL8vTDPTAjLwHPOdz7NcwJun-HyJXeK