实现JSp与数据库连接的登录
====数据库
CREATE TABLE user ( userid VARCHAR(30) PRIMARY KEY, name VARCHAR(30) NOT NULL, password VARCHAR(32) NOT NULL ); INSERT INTO user(userid, name, password) VALUES('admin', 'administrator','admin');
login.jsp界面：
<%@ page language="java" contentType="text/html" pageEncoding="UTF-8"%>
<html>
<head>
<title>www.school.com</title>
</head>
<body>
<h1>登录操作</h1>
<hr>
<form action="login_check.jsp" method="post">
<table border="1">
<tr>
<td colspan="2">用户登录</td>
</tr>
<tr>
<td>登录ID：</td>
<td><input type="text" name="id"></td>
</tr>
<tr>
<td>登录密码：</td>
<td><input type="password" name="password"></td>
</tr>
<tr>
<td colspan="2"><input type="submit" value="登录"> <input
type="reset" value="重置"></td>
</tr>
</table>
</form>
</body>
</html>
login_check.jsp界面：（实现数据库的连接及操作）
<%@page import="java.nio.channels.SeekableByteChannel"%> <%@ page language="java" contentType="text/html" pageEncoding="UTF-8"%> <%@ page import="java.sql.*"%> <html> <head> <title>www.school.com</title> </head> <body> <%!public static final String DBDRIVER = "com.mysql.jdbc.Driver"; public static final String DBURL = "jdbc:mysql://localhost:3306/jsp"; public static final String DBUSER = "root"; public static final String DBPASS = "root";%> <% Connection conn = null; PreparedStatement pstmt = null; ResultSet rs = null; boolean flag = false; String name = null; %> <% try { Class.forName(DBDRIVER); conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS); String sql = "SELECT name FROM user WHERE userid=? AND password=?"; pstmt = conn.prepareStatement(sql); pstmt.setString(1, request.getParameter("id")); pstmt.setString(2, request.getParameter("password")); rs = pstmt.executeQuery(); if (rs.next()) { name = rs.getString(1); flag = true; } } catch (Exception e) { e.printStackTrace(); } finally { try { if (rs != null) rs.close(); if (pstmt != null) pstmt.close(); if (conn != null) conn.close(); if (flag) { request.getRequestDispatcher("login_success.jsp").forward(request, response); } else { response.sendRedirect("login_failure.jsp"); } } catch (Exception e) { e.printStackTrace(); } } %> </body> </html>
login_success.jsp界面：（登录成功界面）
<%@ page language="java" contentType="text/html" pageEncoding="UTF-8"%>
<html>
<head>
<title>www.school.com</title>
</head>
<body>
<h1>登录操作</h1><hr>
<h2>登录成功</h2>
<h2>欢迎<font color="red">
</font>光临！</h2>
</body>
</html>
login_failure.jsp界面：（失败界面）
<%@ page language="java" contentType="text/html" pageEncoding="UTF-8"%>
<html>
<head>
<title>www.school.com</title>
</head>
<body>
<h1>登录失败</h1><hr>
<h2>登录失败，请重新<a href="login.jsp">登录</a>！</h2>
</body>
</html>
