大概流程：
在java web项目中 导入sqljdbc4的包
在java Resources中完成java代码
在webContent 下建立一个存放自己写jsp的文件夹
将sqljdbc4和jstl-1.2 包粘贴载WEB-INF文件下的lib文件下。
java web 登录界面源代码：
1.Data_uil.java
import java.sql.*;
public class Data_uil
{
public Connection getConnection()
{
try{
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
}catch(ClassNotFoundException e)
{
e.printStackTrace();
}
String user="***";
String password="***";
String url="jdbc:sqlserver://127.0.0.1:1433;DatabaseName=***";
Connection con=null;
try{
con=DriverManager.getConnection(url,user,password);
}catch(SQLException e)
{
e.printStackTrace();
}
return con;
}
public String selectPassword(String username)
{
Connection connection=getConnection();
String sql="select *from login where username=?";
PreparedStatement preparedStatement=null;
ResultSet result=null;
String password=null;
try{
preparedStatement=connection.prepareStatement(sql);
preparedStatement.setString(1,username);
result=preparedStatement.executeQuery();//可执行的 查询
if(result.next())
password=result.getString("password");
}catch(SQLException e){
e.printStackTrace();
}finally
{
close(preparedStatement);
close(result);
close(connection);
}
System.out.println("找到的数据库密码为："+password);
return password;
}
public void close (Connection con)
{
try{
if(con!=null)
{
con.close();
}
}catch(SQLException e)
{
e.printStackTrace();
}
}
public void close (PreparedStatement preparedStatement)
{
try{
if(preparedStatement!=null)
{
preparedStatement.close();
}
}catch(SQLException e)
{
e.printStackTrace();
}
}
public void close(ResultSet resultSet)
{
try{
if(resultSet!=null)
{
resultSet.close();
}
}catch(SQLException e)
{
e.printStackTrace();
}
}
}
2.login_check.jsp:
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>验证用户密码</title>
</head>
<body>
<jsp:useBean id="util" class="util.Data_uil" scope="page" />
<%
String username=(String)request.getParameter("username");
String password=(String)request.getParameter("password");
if(username==null||"".equals(username))
{
out.print("<script language=‘javaScript‘> alert(‘用户名不能为空‘);</script>");
response.setHeader("refresh", "0;url=user_login.jsp");
}
else
{
System.out.println("输入的用户名:"+username);
String passwordInDataBase=util.selectPassword(username);
System.out.println("密码："+passwordInDataBase);
if(passwordInDataBase==null||"".equals(passwordInDataBase))
{
out.print("<script language=‘javaScript‘> alert(‘用户名不存在‘);</script>");
response.setHeader("refresh", "0;url=user_login.jsp");
}
else if(passwordInDataBase.equals(password))
{
out.print("<script language=‘javaScript‘> alert(‘登录成功‘);</script>");
response.setHeader("refresh", "0;url=loginSucces.jsp");
}
else
{
out.print("<script language=‘javaScript‘> alert(‘密码错误‘);</script>");
response.setHeader("refresh", "0;url=user_login.jsp");
}
}
%>
</body>
</html>
3.loginSucces.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<hr size="10" width="26%" align="left" color="green">
<font size="6" color="red" >登录成功 </font>
<hr size="10" width="26%" align="left" color="green">
</body>
</html>
4.user_login.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>登录界面</title>
</head>
<body background="C:\Users\win8\workspace\Login\image\9dcbdc339e72a5663b5c289fb5573c13_10.jpg" >
<center>
<br><br><br><br><br><br>
<h1 style="color:yellow">Login</h1>
<br>
<form name="loginForm" action="login_check.jsp" method="post">
<table Border="0" >
<tr >
<td>账号</td>
<td><input type="text" name="username"></td>
</tr>
<tr>
<td>密码</td>
<td><input type="password" name="password">
</td>
</tr>
</table>
<br>
<input type="submit" value="登录" style="color:#BC8F8F">
</form>
</center>
</body>
</html>
运行结果截图：
时间： 2024-08-27 09:55:51