时间：2020-11-07 21:39:51 | 栏目：JSP代码 | 点击：次
本文实例讲述了jsp+jdbc实现连接数据库的方法。分享给大家供大家参考。具体如下：
初次尝试JSP+jdbc，按照书上的例子折腾了半天，就是连不上数据库。于是在网上找材料，终于发现，老的jar包与新版数据库直接不兼容。于是下了新的数据库jdbc包，试了一下，果然搞定。这里，把这个程序跟大家共享下，程序实现了网页登录界面上提取用户名与密码，然后与数据库中用户名密码对应，从而决定程序是否通过登录。
inc.jsp文件：
<%@ page import="java.sql.Connection"%> <%@ page import="java.sql.DriverManager"%> <%@ page import="java.sql.Statement"%> <%@ page import="java.sql.ResultSet"%> <%@ page import="java.sql.ResultSetMetaData"%> <% String drv = "com.mysql.jdbc.Driver"; String url = "jdbc:mysql://localhost:3306/demo"; String usr = "nari"; String pwd = "nari"; %>
welcome.jsp文件：
<html> <body> welcome<br> </body> </html>
login_action.jsp文件：
<%@ include file="inc.jsp" %>
<%
String username = request.getParameter("username");
String password = request.getParameter("password");
if(username == null || password == null){
response.sendRedirect("index.jsp");
}
boolean isValid = false;
String sql = "select * from user where username='"+username+"'and password='"+password+"'";
out.println("===>"+sql);
try{
Class.forName(drv).newInstance();
Connection conn = DriverManager.getConnection(url, usr,pwd);
Statement stm = conn.createStatement();
ResultSet rs = stm.executeQuery(sql);
if(rs.next())isValid = true;
rs.close();
stm.close();
conn.close();
}catch(Exception e){
e.printStackTrace();
out.println(e);
}
if(isValid){
response.sendRedirect("welcome.jsp");
}else response.sendRedirect("index.jsp");
%>
<% /*
if(username.endsWith("a"))response.sendRedirect("welcome.jsp");
else response.sendRedirect("index.jsp");
*/%>
index.jsp文件：
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<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="description" content="This is my page">
</head>
<body>
miThis is my JSP page.<br>
</body>
</html>
<form name="form1" action="login_action.jsp" method="post">
<table width="200" border="1">
<tr>
<td colspan="2">登录窗口</td>
</tr>
<tr>
<td>用户名</td>
<td><input type="text" name="username" size="10"/></td>
</tr>
<tr>
<td>密码</td>
<td><input type ="password" name="password" size="10"/></td>
</tr>
<tr>
<td colspan="2"><input type="submit" name="submit" value="登录">
<a href="register.jsp">注册新用户</a></td>
</tr>
</table>
</form>
程序使用tomcat进行发布，myeclipse进行编辑和调试
希望本文所述对大家的jsp程序设计有所帮助。