+ import java.sql.*;
+
+ public class OracleJDBCExample {
+
+ public static void main(String[] args) {
+ try {
+ // Load the Oracle Type 2 driver (OCI driver)
+ // The Oracle OCI driver uses the Oracle Client libraries to connect to the Oracle DB
+ Class.forName("oracle.jdbc.OracleDriver");
+ System.out.println("Driver Loaded Successfully!");
+
+ // Establish a connection using Type 2 driver (OCI)
+ // You must have the Oracle client (OCI) installed and configured
+ Connection conn = DriverManager.getConnection(
+ "jdbc:oracle:oci8:@localhost:1521:orcl", // JDBC URL for OCI driver
+ "username", // Replace with your Oracle username
+ "password" // Replace with your Oracle password
+ );
+ System.out.println("Connection Established Successfully!");
+
+ // Create a statement
+ Statement stmt = conn.createStatement();
+
+ // Execute a query
+ String query = "SELECT id, Name FROM students"; // SQL query to retrieve student data
+ ResultSet rs = stmt.executeQuery(query);
+
+ // Process the result set
+ while (rs.next()) {
+ System.out.println("ID = " + rs.getInt("id") + ", Name = " + rs.getString("Name"));
+ }
+
+ // Close resources
+ rs.close();
+ stmt.close();
+ conn.close();
+ System.out.println("Connection Closed Successfully!");
+ } catch (Exception e) {
+ System.out.println("Something went wrong: " + e.getMessage());
+ }
+ }
+ }
+
+
+
+ Part 1: JSP (Login Page) login.jsp
+
+<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
+ <%@ page import="java.io.*, javax.servlet.*, javax.servlet.http.*" %>
+ <html>
+ <head>
+ <title>Login Page</title>
+ </head>
+ <body>
+ <h2>Login Form</h2>
+ <form action="LoginServlet" method="post">
+ <label for="username">Username:</label><br>
+ <input type="text" id="username" name="username" required><br><br>
+
+ <label for="password">Password:</label><br>
+ <input type="password" id="password" name="password" required><br><br>
+
+ <button type="submit">Login</button>
+ </form>
+ </body>
+ </html>
+
+
+
+Part 2: Servlet (Backend Logic) LoginServlet.java
+
+ import java.io.*;
+import javax.servlet.*;
+import javax.servlet.http.*;
+
+public class LoginServlet extends HttpServlet {
+ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+ // Set response content type
+ response.setContentType("text/html");
+
+ // Get the user input from the login form
+ String username = request.getParameter("username");
+ String password = request.getParameter("password");
+
+ // Logic to validate the credentials (For simplicity, using hardcoded values)
+ PrintWriter out = response.getWriter();
+ if ("admin".equals(username) && "password123".equals(password)) {
+ // If valid, redirect to a welcome page
+ out.println("Welcome, " + username + "!
");
+ out.println("You have logged in successfully.
");
+ } else {
+ // If invalid, send an error message
+ out.println("Invalid login credentials.
");
+ out.println("");
+ }
+ }
+}
+
+
+
+Using Servlet
+
+ import java.io.*;
+import javax.servlet.*;
+import javax.servlet.http.*;
+import java.sql.*;
+
+ public class UserServlet extends HttpServlet {
+ protected void doGet(HttpServletRequest request, HttpServletResponse response)
+ throws ServletException, IOException {
+ response.setContentType("text/html");
+ PrintWriter out = response.getWriter();
+
+ try {
+ // Connect to the database
+ Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb",
+ "root", "password");
+
+ // Fetch the first 5 users
+ String query = "SELECT id, username, password FROM users LIMIT 5";
+ Statement stmt = conn.createStatement();
+ ResultSet rs = stmt.executeQuery(query);
+
+ // Start HTML output
+ out.println("<html><body>");
+ out.println("<h2>User Details</h2>");
+ out.println("<table border='1'><tr><th>ID</th><th>Username</th><th>Password</th></tr>");
+
+
+ // Loop through the result set and display data in a table
+ while (rs.next()) {
+ out.println("<tr>");
+ out.println("<td>" + rs.getInt("id") + "</td>");
+ out.println("<td>" + rs.getString("username") + "</td>");
+ out.println("<td>" + rs.getString("password") + "</td>");
+ out.println("</tr>");
+ }
+ out.println("</table>");
+ out.println("</body></html>");
+
+ // Close resources
+ rs.close();
+ stmt.close();
+ conn.close();
+ } catch (Exception e) {
+ out.println("Error: " + e.getMessage());
+ }
+ }
+ }
+
+
+
+ Using JSP
+
+ <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
+<%@ page import="java.sql.*, java.util.*" %>
+<html>
+<head>
+ <title>User Details</title>
+ <style>
+ table {
+ width: 50%;
+ margin: 50px auto;
+ border-collapse: collapse;
+ }
+ th, td {
+ padding: 8px;
+ text-align: left;
+ border: 1px solid #ddd;
+ }
+ th {
+ background-color: #f2f2f2;
+ }
+ </style>
+</head>
+<body>
+ <h2 style="text-align: center;">User Details</h2>
+ <table>
+ <thead>
+ <tr>
+ <th>ID</th>
+ <th>Username</th>
+ <th>Password</th>
+ </tr>
+ </thead>
+ <tbody>
+ <%
+ // Establish the database connection using the utility class
+ Connection conn = null;
+ Statement stmt = null;
+ ResultSet rs = null;
+
+ try {
+ conn = DBConnection.getConnection(); // Use the DBConnection class
+ stmt = conn.createStatement();
+
+ // Query to fetch first 5 users from the database
+ String query = "SELECT id, username, password FROM users LIMIT 5";
+ rs = stmt.executeQuery(query);
+
+ // Loop through the result set and display user data in the table
+ while (rs.next()) {
+ out.println("<tr>");
+ out.println("<td>" + rs.getInt("id") + "</td>");
+ out.println("<td>" + rs.getString("username") + "</td>");
+ out.println("<td>" + rs.getString("password") + "</td>");
+ out.println("</tr>");
+ }
+ } catch (SQLException e) {
+ out.println("<tr><td colspan='3'>Error: " + e.getMessage() + "</td></tr>");
+ } finally {
+ // Close the database resources
+ try {
+ if (rs != null) rs.close();
+ if (stmt != null) stmt.close();
+ if (conn != null) conn.close();
+ } catch (SQLException e) {
+ out.println("<tr><td colspan='3'>Error closing resources: " +
+ e.getMessage() + "</td></tr>");
+ }
+ }
+ %>
+ </tbody>
+ </table>
+</body>
+</html>
+
+
+
+ Servlet: CookieServlet.java +
+
+ import java.io.*;
+import javax.servlet.*;
+import javax.servlet.http.*;
+import java.util.*;
+import java.text.*;
+
+public class CookieServlet extends HttpServlet {
+
+ private static final String LOG_FILE_PATH = "C:/logs/application.log";
+ // Change this path based on your system
+
+ @Override
+ protected void doGet(HttpServletRequest request, HttpServletResponse response)
+ throws ServletException, IOException {
+ response.setContentType("text/html");
+ PrintWriter out = response.getWriter();
+
+ // Create a new cookie
+ String userId = UUID.randomUUID().toString(); // Generate a unique user ID
+ Cookie userCookie = new Cookie("userID", userId);
+ userCookie.setMaxAge(60 * 60); // Set cookie expiration to 1 hour
+ response.addCookie(userCookie);
+
+ // Log the request information
+ logRequestToFile(request);
+
+ out.println("<html>");
+ out.println("<body>");
+ out.println("<h2>Cookie Created Successfully!</h2>");
+ out.println("<p>Your unique user ID (Cookie): " + userId + "</p>");
+ out.println("<p><a href='log.jsp'>Click here to view the log file</a></p>");
+ out.println("</body>");
+ out.println("</html>");
+ }
+
+ // Method to log request information into a log file
+ private void logRequestToFile(HttpServletRequest request) {
+ try {
+ PrintWriter logWriter = new PrintWriter(new FileWriter(LOG_FILE_PATH, true)); // Append mode
+ String timestamp = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date());
+ String logMessage = timestamp + " - Access from IP: " + request.getRemoteAddr()
+ + " with User-Agent: " + request.getHeader("User-Agent");
+ logWriter.println(logMessage);
+ logWriter.close();
+ } catch (IOException e) {
+ System.out.println("Error logging request: " + e.getMessage());
+ }
+ }
+}
+
+
+ JSP: log.jsp +
+
+ <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
+<%@ page import="java.io.*, java.util.*" %>
+<html>
+<head>
+ <title>Log File and Cookie Information</title>
+</head>
+<body>
+ <h2>Cookie Information</h2>
+ <p>
+ <%
+ Cookie[] cookies = request.getCookies();
+ if (cookies != null) {
+ for (Cookie cookie : cookies) {
+ if ("userID".equals(cookie.getName())) {
+ out.println("Your User ID (Cookie): " + cookie.getValue());
+ }
+ }
+ } else {
+ out.println("No cookies found.");
+ }
+ %>
+ </p>
+
+ <h2>Log File Contents</h2>
+ <pre>
+ <%
+ String logFilePath = "C:/logs/application.log";
+ // Make sure the path is correct for your environment
+ File logFile = new File(logFilePath);
+ if (logFile.exists()) {
+ BufferedReader reader = new BufferedReader(new FileReader(logFile));
+ String line;
+ while ((line = reader.readLine()) != null) {
+ out.println(line);
+ }
+ reader.close();
+ } else {
+ out.println("Log file does not exist.");
+ }
+ %>
+ </pre>
+</body>
+</html>
+
+
+