jsp 实栗 jsp + jdbc 实现登录
实现思路
一个表单页，输入用户登录和密码，然后信息提交到jsp页面进行验证，如果可以服务器跳转到登录成功页，失败，跳转到错误页
跳转的时候窗口的URL地址会发生变化
代码如下
编写登录代码
登录
<!DOCTYPE html>
<html lang="zh_CN">
<head>
<meta charset="UTF-8">
<title>登录</title>
</head>
<body>
<h1>登录操作</h1>
<form action="login_check.jsp" method="post">
<h1>用户登录</h1>
<p>
登录id
<input type="text" name="id"/>
</p>
<p>
登录密码
<input type="password" name="password"/>
</p>
<input type="submit" value="登录"/>
<input type="reset" value="重置"/>
</form>
</body>
</html>
登录处理
<%@ page import="java.sql.*" %>
<%--
Created by IntelliJ IDEA.
User: ming
Date: 19-3-9
Time: 下午5:50
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<%!
// 数据库驱动程序
public static final String DBDRIVER = "com.mysql.cj.jdbc.Driver";
// 数据库连接地址
public static final String DBURL = "jdbc:mysql://47.94.95.84:32786/test";
// 用户名
public static final String DBUSER = "root";
// 密码
public static final String DBPASS = "ABCcba20170607";
%>
<%
// 连接对象
Connection connection = null;
// 操作
PreparedStatement preparedStatement = null;
// 结果
ResultSet resultSet = null;
// 标志位
boolean falge = false;
// 用户真实姓名
String name = null;
%>
<%
try{
Class.forName(DBDRIVER);
// 获得连接
connection = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
// 编写sql验证ID 密码
String sql = "SELECT name FROM user WHERE userid = ? AND password = ?";
// 实例化操作对象
preparedStatement = connection.prepareStatement(sql);
// 设置查询内容
preparedStatement.setString(1, request.getParameter("id"));
preparedStatement.setString(2, request.getParameter("password"));
// 执行查询
resultSet = preparedStatement.executeQuery();
// 如果可以查询到，表示合法用户
if(resultSet.next()){
name = resultSet.getString(1);
// 修改标志位
falge = true;
}
}catch (Exception e){
e.printStackTrace();
}finally {
try{
resultSet.close();
preparedStatement.close();
connection.close();
}catch (Exception e){
e.printStackTrace();
}
}
%>
<%
// 登录成功
if(falge){
// 进行服务器端跳转
%>
<jsp:forward page="./login_sucess.jsp">
<jsp:param name="uname" value="<%=name%>"/>
</jsp:forward>
<%
}else{
%>
<jsp:forward page="./login_failure.html"/>
<%
}
%>
</body>
</html>
登录完成
<%--
Created by IntelliJ IDEA.
User: ming
Date: 19-3-9
Time: 下午10:22
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<h1>登录成功</h1>
<%=request.getParameter("uname")%>
</body>
</html>
登录失败
<%--
Created by IntelliJ IDEA.
User: ming
Date: 19-3-9
Time: 下午10:22
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<h1>登录成功</h1>
<%=request.getParameter("uname")%>
</body>
</html>
效果演示
登录界面
