Code for User Validation using JSP

by gopal krishna on February 22, 2024 in Adv JAVA

index.html


<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Login</title>
</head>
<body>
    <h2>Login</h2>
    <form action="login.jsp" method="post">
        <label for="username">Username:</label>
        <input type="text" id="username" name="username" required><br><br>
        
        <label for="password">Password:</label>
        <input type="password" id="password" name="password" required><br><br>
        
        <input type="submit" value="Login">
    </form>
</body>
</html>



login.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ page import="java.sql.*" %>
<%@ page import="java.io.*" %>
<%
    String un = request.getParameter("username");
    String pass = request.getParameter("password");   
    try {
        Class.forName("com.mysql.jdbc.Driver");
        Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/gk", "root", "");  
        // SQL query to validate user
        String query = "SELECT * FROM login WHERE un=? AND pass=?";
        PreparedStatement pstmt = con.prepareStatement(query);
        pstmt.setString(1, un);
        pstmt.setString(2, pass);        
        ResultSet rs = pstmt.executeQuery();
        if (rs.next())
        {
            // Valid user
            out.println("Welcome " + un);
        } else {
            // Invalid user
            out.println("Invalid username or password");
        }   
        con.close();
    }
    catch (Exception e) {
        out.println("Error: " + e);
    }
%>


Output: