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package test;
 
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
@WebServlet("/updateUser")
public class jsplog extends HttpServlet {
    private static final long serialVersionUID = 1L;
 
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // Get user input from the form
        String id = request.getParameter("id");
        String name = request.getParameter("name");
 
        // Database connection parameters
        String jdbcUrl = "jdbc:mysql://localhost:3306/nehal";
        String dbUser = "root";
        String dbPassword = "nehal@123";
 
        Connection conn = null;
        PreparedStatement pstmt = null;
 
        try {
            // Load the JDBC driver
            Class.forName("com.mysql.cj.jdbc.Driver");
 
            // Establish a connection to the database
            conn = DriverManager.getConnection(jdbcUrl, dbUser, dbPassword);
 
            // Prepare SQL update query
            String sql = "UPDATE emp SET name = ? WHERE id = ?";
            pstmt = conn.prepareStatement(sql);
            pstmt.setString(1, name); // Set new name
            pstmt.setInt(2, Integer.parseInt(id)); // Set user ID
 
            // Execute update
            int rowsUpdated = pstmt.executeUpdate();
 
            // Respond to the client
            response.setContentType("text/html");
            PrintWriter out = response.getWriter();
            if (rowsUpdated > 0) {
                out.println("<h1>Record updated successfully for user ID: " + id + "</h1>");
            } else {
                out.println("<h1>No user found with ID: " + id + "</h1>");
            }
 
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                if (pstmt != null) pstmt.close();
                if (conn != null) conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}
//html
<!DOCTYPE html>
<html>
<head>
    <title>Update User</title>
</head>
<body>
    <h2>Update User Information</h2>
    <form action="updateUser" method="post">
        <label for="id">User ID:</label>
        <input type="text" id="id" name="id" required><br><br>
 
        <label for="name">New Name:</label>
        <input type="text" id="name" name="name" required><br><br>
 
        <input type="submit" value="Update">
    </form>
</body>
</html>

Database Connection JSP

@login123

<%@ page import="java.sql.*" %>
<html>
<body>
<%
    String url = "jdbc:oracle:thin:@//localhost:1521/XE";
    String user = "system";
    String password = "abhi";
    Connection conn = null;
    try {
        Class.forName("oracle.jdbc.driver.OracleDriver");
        conn = DriverManager.getConnection(url, user, password);
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT * FROM employee");
        while (rs.next()) {
%>
            <p>User: <%= rs.getString("ename") %></p>
<%
        }
    } catch (Exception e) {
        out.println("Error: " + e.getMessage());
    } finally {
        if (conn != null) conn.close();
    }
%>
</body>
</html>

Login JSP

@login123

<%@ page language="java" %>
<html>
<head>
    <title>Login</title>
</head>
<body>
    <h2>User Login</h2>
    <form action="validateLogin.jsp" method="post">
        <label>Username:</label>
        <input type="text" name="username" required><br>
        <label>Password:</label>
        <input type="password" name="password" required><br>
        <input type="submit" value="Login">
    </form>
</body>
</html>



<%@ page import="java.sql.*" %>
<html>
<body>
<%
    String username = request.getParameter("username");
    String password = request.getParameter("password");
    boolean isValid = false;

    String url = "jdbc:oracle:thin:@//localhost:1521/XE";
    String duser = "system";
    String dpassword = "abhi";
    Connection conn = null;
    try {
    	Class.forName("oracle.jdbc.driver.OracleDriver");
        conn = DriverManager.getConnection(url, duser, dpassword);
        PreparedStatement ps = conn.prepareStatement("SELECT * FROM users1 WHERE username=? AND password=?");
        ps.setString(1, username);
        ps.setString(2, password);
        ResultSet rs = ps.executeQuery();
        isValid = rs.next();
    } catch (Exception e) {
        out.println("Error: " + e.getMessage());
    } finally {
        if (conn != null) conn.close();
    }
    if (isValid) {
        out.println("Login Successful");
        out.println("<h1> hi "+ username+"! </h1>");
    } else {
        out.println("Invalid Credentials");
    }
%>
</body>
</html>

Connect JSP

@login123

<%@ page import="java.sql.*" %>
<html>
<body>
<%
    String url = "jdbc:oracle:thin:@//localhost:1521/XE";
    String user = "system";
    String password = "abhi";
    Connection conn = null;
    try {
        Class.forName("oracle.jdbc.driver.OracleDriver");
        conn = DriverManager.getConnection(url, user, password);
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT * FROM employee");
        while (rs.next()) {
%>
            <p>User: <%= rs.getString("ename") %></p>
<%
        }
    } catch (Exception e) {
        out.println("Error: " + e.getMessage());
    } finally {
        if (conn != null) conn.close();
    }
%>
</body>
</html>

Date JSP

@login123

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8" import="java.util.Date" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
   <p>Current Date and Time: <%= new Date() %></p>
</body>
</html>

Request JSP

@login123

<html>
<body>
    <form action="request.jsp" method="post">
        Name: <input type="text" name="name"><br>
        Age: <input type="number" name="age"><br>
        <input type="submit" value="Submit">
    </form>
</body>
</html>

<html>
<body>
    <p>Name: <%= request.getParameter("name") %></p>
    <p>Age: <%= request.getParameter("age") %></p>
</body>
</html>

Scrollable And Updatable Result Set

@login123

// File: ScrollableAndUpdatableResultSetExample.java
import java.sql.Connection;
import java.sql.Date;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class UpdateScrollResultset {
    public static void main(String[] args) throws ClassNotFoundException {
       
        //Class.forName("oracle.jdbc.driver.OracleDriver");
       //String jdbcURL = "jdbc:oracle:thin:@localhost:1521/XE";
        String jdbcURL = "jdbc:mysql://localhost:3306/jdbcdb"; 
        String username = ""; 
        String password = ""; 

    
        String query = "SELECT emp_id, empname, dob,salary,dept_id FROM employee";

        try (Connection connection = DriverManager.getConnection(jdbcURL, username, password)) {

            
            Statement statement = connection.createStatement(
                ResultSet.TYPE_SCROLL_SENSITIVE,      
                ResultSet.CONCUR_UPDATABLE      
            );

            
            ResultSet resultSet = statement.executeQuery(query);

            
            if (resultSet.last()) {
                System.out.println("Last Employee:");
                printEmployee(resultSet);
            }

            
            if (resultSet.first()) {
                System.out.println("First Employee:");
                printEmployee(resultSet);
            }

            
            if (resultSet.absolute(3)) {
                System.out.println("Third Employee:");
                printEmployee(resultSet);
            }

   
            resultSet.absolute(2); /
            double oldSalary = resultSet.getDouble("salary");
            double newSalary = oldSalary * 1.05; 
            resultSet.updateDouble("salary", newSalary);
            

            resultSet.updateRow();

            System.out.println("Updated Employee (2nd row) Salary: ");
            printEmployee(resultSet);

          
            resultSet.moveToInsertRow(); 
            resultSet.updateInt("emp_id",9);
            resultSet.updateString("empname", "Karthik");
            resultSet.updateDate("dob", Date.valueOf("1990-01-01"));
            resultSet.updateDouble("salary", 500000);
            resultSet.updateInt("dept_id", 15);
            resultSet.insertRow(); // Insert the row in the database
            System.out.println("Inserted a new employee.");
    
            // Delete the newly inserted row
            if (resultSet.last()) {
                resultSet.deleteRow(); // Delete the last row (which was just inserted)
                System.out.println("Deleted the newly inserted employee.");
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    // Utility method to print employee details
    private static void printEmployee(ResultSet resultSet) throws SQLException {
        int empId = resultSet.getInt("emp_id");
        String empName = resultSet.getString("empname");
        Date dob = resultSet.getDate("dob");
        double salary = resultSet.getDouble("salary");
        int deptId = resultSet.getInt("dept_id");

        System.out.println("Employee ID: " + empId);
        System.out.println("Employee Name: " + empName);
       // System.out.println("Date of Birth: " + dob);
        System.out.println("Salary: " + salary);
        System.out.println("Department ID: " + deptId);
        System.out.println("------------------------");
    }
}

Multiple Connection

@login123

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;

public class JdbcMultipleConn{
    public static void main(String[] args) {
        Connection conn1 = null;
        Connection conn2 = null;
        Connection conn3 = null;

        try{
            //Connection no #1
            String url1 = "jdbc:mysql://localhost:3306/jdbcdb"; 
            String user = "root";
            String password = "ramesh";
            conn1 = DriverManager.getConnection(url1, user, password);
            if (conn1 != null) {           
                System.out.println("Connected to the database jdbcdb");
                    }
                String url2 = "jdbc:mysql://localhost:3306/jdbcdb?user=root&password=ramesh";
            conn2 = DriverManager.getConnection(url2);
            if (conn2 != null) {
            System.out.println("Connected to the database jdbcdb");
        }

            String url3 = "jdbc:mysql://localhost:3306/jdbcdb";
            Properties info = new Properties();
            info.put("user", "root");
            info.put("password", "ramesh");
            conn3 = DriverManager.getConnection(url3, info);
                if (conn3 != null) {
                System.out.println("Connected to the database jdbcdb");
        }
        
        }

        catch (SQLException ex) {
            System.out.println("An error occurred. Maybe user/password is invalid");
            ex.printStackTrace();
                }
        }
    }

jsp request 1 page

@wtlab

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<%
    // Initialize variables to hold form data
    String name = request.getParameter("name");
    String age = request.getParameter("age");
    boolean formSubmitted = (name != null && age != null); // Check if form is submitted
%>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Parameter Input Form</title>
</head>
<body>
    <h2>Enter Your Details</h2>

    <!-- Display the form if no data has been submitted -->
    <% if (!formSubmitted) { %>
        <form action="requestjsp.jsp" method="post">
            Name: <input type="text" name="name" required><br><br>
            Age: <input type="text" name="age" required><br><br>
            <input type="submit" value="Submit">
        </form>
    <% } else { %>
        <!-- Display submitted data if form is submitted -->
        <h2>Your Details:</h2>
        <p>Name: <%= name %></p>
        <p>Age: <%= age %></p>
    <% } %>
</body>
</html>

form Parameters

@webtechnologies

Add.java
@WebServlet( urlPatterns={"/add"})
public class Add extends HttpServlet {
    public void service(HttpServletRequest req, HttpServletResponse res) throws IOException {
    	
    	int i=Integer.parseInt(req.getParameter("num1"));
    	int j=Integer.parseInt(req.getParameter("num2"));
    	
    	int k=i+j;
    	PrintWriter out=res.getWriter();
    	out.println(k);
    			
    }

}

index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Add numbers</title>
</head>
<body>
	
	<form action="add" method="get">
		enter num1:<input type="text" name="num1"><br>
		Enter num2:<input type="text" name="num2">
		
		<br>
		<input type="submit" value="Add">
	</form>
</body>
</html>

book (dtd)

@webtechnologies

books.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE bookstore SYSTEM "bookstore.dtd">
<bookstore>
    <book>
        <title>Introduction to XML</title>
        <author>John Doe</author>
        <isbn>978-0-123456-47-2</isbn>
        <publisher>Example Press</publisher>
        <edition>3rd</edition>
        <price>39.99</price>
    </book>
    <book>
        <title>Advanced XML Concepts</title>
        <author>Jane Smith</author>
        <isbn>978-0-765432-10-5</isbn>
        <publisher>Tech Books Publishing</publisher>
        <edition>1st</edition>
        <price>45.00</price>
    </book>
</bookstore>

bookstore.dtd
<!ELEMENT bookstore (book+)>
<!ELEMENT book (title, author, isbn, publisher, edition, price)>
<!ELEMENT title (#PCDATA)>
<!ELEMENT author (#PCDATA)>
<!ELEMENT isbn (#PCDATA)>
<!ELEMENT publisher (#PCDATA)>
<!ELEMENT edition (#PCDATA)>
<!ELEMENT price (#PCDATA)>

16. Write a java based application to demonstrate the Scrollable Result sets.

@webtechnologies

import java.sql.*;

public class ScrollableResultSetExample {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/your_database";
        String username = "root"; 
        String password = "your_password";

        try {
            Connection connection = DriverManager.getConnection(url, username, password);

            String query = "SELECT * FROM your_table";
            Statement statement = connection.createStatement(
                    ResultSet.TYPE_SCROLL_INSENSITIVE, 
                    ResultSet.CONCUR_READ_ONLY);
            
            ResultSet resultSet = statement.executeQuery(query);
            
            if (resultSet.last()) {
                System.out.println(resultSet.getString("column_name"));
            }

            if (resultSet.first()) {
                System.out.println(resultSet.getString("column_name"));
            }

            resultSet.close();
            statement.close();
            connection.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

15. Write a java program to demonstrate the usage of JDBC in performing various DML statements using prepared statements.

@webtechnologies

import java.sql.*;

public class DMLExamples {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/your_database";
        String username = "root";
        String password = "your_password";

        try (Connection connection = DriverManager.getConnection(url, username, password)) {
            System.out.println("Connected to the database.");

          
            String insertSQL = "INSERT INTO your_table (column1, column2) VALUES (?, ?)";
            try (PreparedStatement insertStmt = connection.prepareStatement(insertSQL)) {
                insertStmt.setString(1, "Alice");
                insertStmt.setInt(2, 30);
                int rowsInserted = insertStmt.executeUpdate();
                System.out.println(rowsInserted + " row(s) inserted.");
            }

            
            String updateSQL = "UPDATE your_table SET column2 = ? WHERE column1 = ?";
            try (PreparedStatement updateStmt = connection.prepareStatement(updateSQL)) {
                updateStmt.setInt(1, 35); // New value for column2
                updateStmt.setString(2, "Alice"); // Condition
                int rowsUpdated = updateStmt.executeUpdate();
                System.out.println(rowsUpdated + " row(s) updated.");
            }

          
            String selectSQL = "SELECT * FROM your_table";
            try (PreparedStatement selectStmt = connection.prepareStatement(selectSQL)) {
                ResultSet resultSet = selectStmt.executeQuery();
                System.out.println("Data in the table:");
                while (resultSet.next()) {
                    int id = resultSet.getInt("id");
                    String column1 = resultSet.getString("column1");
                    int column2 = resultSet.getInt("column2");
                    System.out.printf("ID: %d, Column1: %s, Column2: %d%n", id, column1, column2);
                }
            }

          
            String deleteSQL = "DELETE FROM your_table WHERE column1 = ?";
            try (PreparedStatement deleteStmt = connection.prepareStatement(deleteSQL)) {
                deleteStmt.setString(1, "Alice");
                int rowsDeleted = deleteStmt.executeUpdate();
                System.out.println(rowsDeleted + " row(s) deleted.");
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

14. Write a java program to establish a connection to a database and execute simple SQL queries.

@webtechnologies

import java.sql.*;

public class DatabaseConnectionExample {
    public static void main(String[] args) {
      
        String url = "jdbc:mysql://localhost:3306/your_database";
        String username = "root"; 
        String password = "your_password";

        try {
           
            Connection connection = DriverManager.getConnection(url, username, password);
            System.out.println("Connection established!");

            
            Statement statement = connection.createStatement();
            
            
            String query = "SELECT * FROM your_table";
            ResultSet resultSet = statement.executeQuery(query);
            
           
            while (resultSet.next()) {
                System.out.println(resultSet.getString("column_name"));
            }

           
            resultSet.close();
            statement.close();
            connection.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

Make sure local branch matches remote branch

@CarlosR

git reset --hard origin/enhance/logging

#groovy

console_getProjectKey_each

@belleJar

import com.atlassian.jira.component.ComponentAccessor

def allProjects = ComponentAccessor.projectManager

def projects = allProjects.projects

projects.each{ project ->
    log.warn(project.key)
}

#groovy

cloud_console_getAllProjects

@belleJar

// Call the Jira REST API to retrieve all projects
def response = get('/rest/api/3/project')
    .header('Content-Type', 'application/json')
    .asObject(List)

// Check for a successful response
if (response.status != 200) {
    return "Error fetching projects: ${response.status} - ${response.statusText}"
}

// Cast the response body to a List of Maps for static type checking
List<Map> projects = response.body as List<Map>

// Extract project data and map to a simplified structure
return projects.collect { project ->
    [
        id   : project['id'],
        key  : project['key'],
        name : project['name']
    ]
}

Fat Arrows in js

@login123

const add = (a, b) => a + b;
console.log("Addition:", add(5, 3)); 


const greet = () => "Hello, World!";
console.log("Greeting:", greet()); 


const square = x => x * x;
console.log("Square of 4:", square(4)); 


const isEven = num => num % 2 === 0;
console.log("Is 10 even?:", isEven(10)); 


const numbers = [1, 2, 3, 4];
const doubled = numbers.map(num => num * 2);
console.log("Doubled Numbers:", doubled); 


const evenNumbers = numbers.filter(num => num % 2 === 0);
console.log("Even Numbers:", evenNumbers);

Login JSP

@signup1

<%@ page import="java.sql.*" %>
<html>
<body>
<%
    String username = request.getParameter("username");
    String password = request.getParameter("password");
    boolean isValid = false;

    String url = "jdbc:oracle:thin:@//localhost:1521/XE";
    String duser = "system";
    String dpassword = "abhi";
    Connection conn = null;
    try {
    	Class.forName("oracle.jdbc.driver.OracleDriver");
        conn = DriverManager.getConnection(url, duser, dpassword);
        PreparedStatement ps = conn.prepareStatement("SELECT * FROM users1 WHERE username=? AND password=?");
        ps.setString(1, username);
        ps.setString(2, password);
        ResultSet rs = ps.executeQuery();
        isValid = rs.next();
    } catch (Exception e) {
        out.println("Error: " + e.getMessage());
    } finally {
        if (conn != null) conn.close();
    }
    if (isValid) {
        out.println("Login Successful");
        out.println("<h1> hi "+ username+"! </h1>");
    } else {
        out.println("Invalid Credentials");
    }
%>
</body>
</html>


<%@ page language="java" %>
<html>
<head>
    <title>Login</title>
</head>
<body>
    <h2>User Login</h2>
    <form action="validateLogin.jsp" method="post">
        <label>Username:</label>
        <input type="text" name="username" required><br>
        <label>Password:</label>
        <input type="password" name="password" required><br>
        <input type="submit" value="Login">
    </form>
</body>
</html>

Connect JSP

@signup1

<%@ page import="java.sql.*" %>
<html>
<body>
<%
    String url = "jdbc:oracle:thin:@//localhost:1521/XE";
    String user = "system";
    String password = "abhi";
    Connection conn = null;
    try {
        Class.forName("oracle.jdbc.driver.OracleDriver");
        conn = DriverManager.getConnection(url, user, password);
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT * FROM employee");
        while (rs.next()) {
%>
            <p>User: <%= rs.getString("ename") %></p>
<%
        }
    } catch (Exception e) {
        out.println("Error: " + e.getMessage());
    } finally {
        if (conn != null) conn.close();
    }
%>
</body>
</html>

Date JSP

@signup1

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8" import="java.util.Date" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
   <p>Current Date and Time: <%= new Date() %></p>
</body>
</html>

Request JSP

@signup1

<html>
<body>
    <form action="request.jsp" method="post">
        Name: <input type="text" name="name"><br>
        Age: <input type="number" name="age"><br>
        <input type="submit" value="Submit">
    </form>
</body>
</html>


<html>
<body>
    <p>Name: <%= request.getParameter("name") %></p>
    <p>Age: <%= request.getParameter("age") %></p>
</body>
</html>

Jdbc Transaction

@login123

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

public class JdbcTransactionExample {

    public static void main(String[] args) {
        Connection conn = null;
        PreparedStatement pstmt1 = null;
        PreparedStatement pstmt2 = null;

        try {
            // Step 1: Establish database connection
            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/bank", "root", "ramesh");

          
            conn.setAutoCommit(false);

         
            String sql1 = "UPDATE bank_account SET balance = balance - ? WHERE account_id = ?";
            pstmt1 = conn.prepareStatement(sql1);
            pstmt1.setDouble(1, 1000); 
            pstmt1.setInt(2, 1);

            String sql2 = "UPDATE bank_account SET balance = balance + ? WHERE account_id = ?";
            pstmt2 = conn.prepareStatement(sql2);
            pstmt2.setDouble(1, 1000); 
            pstmt2.setInt(2, 2);

         
            pstmt1.executeUpdate();
            pstmt2.executeUpdate();

       
            conn.commit();
            System.out.println("Transaction committed successfully");

        } catch (SQLException e) {
          
            if (conn != null) {
                try {
                    conn.rollback();
                    System.out.println("Transaction rolled back due to error");
                } catch (SQLException rollbackEx) {
                    rollbackEx.printStackTrace();
                }
            }
            e.printStackTrace();
        } finally {
            
            try {
                if (pstmt1 != null) pstmt1.close();
                if (pstmt2 != null) pstmt2.close();
                if (conn != null) conn.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        }
    }
}

Result Set Meta Data

@login123

// File: ResultSetMetaDataExample.java
import java.sql.*;

public class ResultSetMetaDataExample {
    public static void main(String[] args) throws ClassNotFoundException {
   
        String jdbcURL = "jdbc:mysql://localhost:3306/jdbcdb"; 
         //String DB_URL = "jdbc:oracle:thin:@localhost:1521:XE";
   
        String username = "";
        String password = "";

       
        String query = "SELECT * FROM employee"; 
//Class.forName("oracle.jdbc.driver.OracleDriver");

        try (Connection connection = DriverManager.getConnection(jdbcURL, username, password);
             Statement statement = connection.createStatement();
             ResultSet resultSet = statement.executeQuery(query)) {

           
            ResultSetMetaData metaData = resultSet.getMetaData();

           
            int columnCount = metaData.getColumnCount();

           
            System.out.println("Table and Column names:");
            for (int i = 1; i <= columnCount; i++) {
                String tableName = metaData.getTableName(i);
                String columnName = metaData.getColumnName(i);
                System.out.print(columnName + " (" + tableName + ") | ");
            }
            System.out.println();

            System.out.println("\nRow data:");
            while (resultSet.next()) {
                for (int i = 1; i <= columnCount; i++) {
                    Object columnValue = resultSet.getObject(i);
                    System.out.print(columnValue + " | ");
                }
                System.out.println(); 
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

JSP request paramaters

@signup_returns

//form.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
    <title>Input Form</title>
</head>
<body>
    <h2>Enter Your Details</h2>
    <form action="process.jsp" method="post">
        <label for="name">Name:</label><br>
        <input type="text" id="name" name="name" required><br><br>

        <label for="email">Email:</label><br>
        <input type="email" id="email" name="email" required><br><br>

        <input type="submit" value="Submit">
    </form>
</body>
</html>


//process.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
    <title>Form Submission Result</title>
</head>
<body>
    <h2>Submitted Details</h2>
    <%
        // Access request parameters using request.getParameter()
        String name = request.getParameter("name");
        String email = request.getParameter("email");

        // Check if parameters are not null (useful for handling cases when accessed directly)
        if (name != null && email != null) {
    %>
        <p><strong>Name:</strong> <%= name %></p>
        <p><strong>Email:</strong> <%= email %></p>
    <%
        } else {
    %>
        <p style="color:red;">No data received!</p>
    <%
        }
    %>
    <br>
    <a href="form.jsp">Go Back</a>
</body>
</html>

Jdbc Multiple Connection

@login123

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;

public class JdbcMultipleConn{
    public static void main(String[] args) {
        Connection conn1 = null;
        Connection conn2 = null;
        Connection conn3 = null;

        try{
            //Connection no #1
            String url1 = "jdbc:mysql://localhost:3306/jdbcdb"; 
            String user = "root";
            String password = "ramesh";
            conn1 = DriverManager.getConnection(url1, user, password);
            if (conn1 != null) {           
                System.out.println("Connected to the database jdbcdb");
                    }
                String url2 = "jdbc:mysql://localhost:3306/jdbcdb?user=root&password=ramesh";
            conn2 = DriverManager.getConnection(url2);
            if (conn2 != null) {
            System.out.println("Connected to the database jdbcdb");
        }

            String url3 = "jdbc:mysql://localhost:3306/jdbcdb";
            Properties info = new Properties();
            info.put("user", "root");
            info.put("password", "ramesh");
            conn3 = DriverManager.getConnection(url3, info);
                if (conn3 != null) {
                System.out.println("Connected to the database jdbcdb");
        }
        
        }

        catch (SQLException ex) {
            System.out.println("An error occurred. Maybe user/password is invalid");
            ex.printStackTrace();
                }
        }
    }

Hit Counter

@signup_returns

import jakarta.servlet.*;
import jakarta.servlet.http.*;
import java.io.*;
import jakarta.servlet.annotation.*;

@WebServlet("/hitcounter")
public class HitCounterServlet extends HttpServlet {
    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // Set the content type to HTML
        response.setContentType("text/html");

        // Get the writer to send the response
        PrintWriter out = response.getWriter();

        // Get the cookies from the request
        Cookie[] cookies = request.getCookies();
        int hitCount = 0;

        // Check if there's a cookie for 'hitCount'
        if (cookies != null) {
            for (Cookie cookie : cookies) {
                if ("hitCount".equals(cookie.getName())) {
                    hitCount = Integer.parseInt(cookie.getValue());
                    break;
                }
            }
        }

        // Increment the hit count
        hitCount++;

        // Create or update the 'hitCount' cookie
        Cookie hitCountCookie = new Cookie("hitCount", String.valueOf(hitCount));
        hitCountCookie.setMaxAge(60 * 60 * 24 * 7); // 1 week expiry time
        response.addCookie(hitCountCookie);

        // Generate the HTML response
        out.println("<html>");
        out.println("<head><title>Hit Counter</title></head>");
        out.println("<body>");
        out.println("<h1>Page hit count: " + hitCount + "</h1>");
        out.println("</body>");
        out.println("</html>");
    }
}

JSP Database

@signup_returns

<%@ page import="java.sql.*" %>
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
    <title>JSP Oracle Database Connectivity</title>
    <style>
        table { width: 60%; margin: 20px auto; border-collapse: collapse; }
        table, th, td { border: 1px solid black; text-align: center; padding: 8px; }
        th { background-color: #f2f2f2; }
        h2 { text-align: center; }
    </style>
</head>
<body>
    <h2>User Details from Oracle Database</h2>
    <%
        // Oracle database connection details
        String url = "jdbc:oracle:thin:@localhost:1521:xe";
        String username = "system"; // Replace with your Oracle username
        String password = "1234"; // Replace with your Oracle password

        Connection conn = null;
        Statement stmt = null;
        ResultSet rs = null;

        try {
            // Load the Oracle JDBC driver
            //Class.forName("oracle.jdbc.driver.OracleDriver");
            
            // Establish the database connection
            conn = DriverManager.getConnection(url, username, password);
            
            // Create a statement object to execute queries
            stmt = conn.createStatement();
            
            // Execute a query to fetch data from the 'users' table
            String query = "SELECT * FROM users";
            rs = stmt.executeQuery(query);
    %>
    <table>
        <tr>
            <th>User ID</th>
            <th>Name</th>
            <th>Email</th>
        </tr>
        <%
            // Iterate through the result set and display data in the table
            while (rs.next()) {
        %>
        <tr>
            <td><%= rs.getInt("user_id") %></td>
            <td><%= rs.getString("name") %></td>
            <td><%= rs.getString("email") %></td>
        </tr>
        <%
            }
        %>
    </table>
    <%
        } catch (Exception e) {
            out.println("<p style='color:red; text-align:center;'>Error: " + e.getMessage() + "</p>");
        } finally {
            // Close all resources to avoid memory leaks
            if (rs != null) try { rs.close(); } catch (SQLException ignored) {}
            if (stmt != null) try { stmt.close(); } catch (SQLException ignored) {}
            if (conn != null) try { conn.close(); } catch (SQLException ignored) {}
        }
    %>
</body>
</html>

Jdbc Connection

@login123

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.ResultSet;
import java.sql.Statement;


public class JdbcConnectionExample {
	
	
	  public static void main(String[] args)throws ClassNotFoundException {
	    Connection con = null;
        Statement st=null;
	    String url = "jdbc:mysql://localhost:3306/books";
	    String username = "root";
	    String password = "ramesh";

	    try {
	      Class.forName("com.mysql.cj.jdbc.Driver");
	      con = DriverManager.getConnection(url, username, password);

	      System.out.println("Connected!");
            st= con.createStatement();
			System.out.println("Inserting Records into the table");
			int rowupdate=st.executeUpdate("insert into book values(33,'Machine Learning through JavaScript','Anderson','Taylor series',2500)");
		    ResultSet rs1=st.executeQuery("Select * from book");	          
                    //Get the values of the record using while loop from result set
                    while(rs1.next())
                    {
                        int id = rs1.getInt(1);
                        String title = rs1.getString(2);
                        String author = rs1.getString(3);
                        String publisher = rs1.getString(4);
                        int price = rs1.getInt(5);
                        //String totalMarks= rs1.getInt(5);
                        //store the values which are retrieved using ResultSet and print them
                    System.out.println(id + ","+title+ ","+author+ ","+publisher +","+price );
                    }
         
	    } catch (SQLException ex) {
	        throw new Error("Error ", ex);
	    } finally {
	      try {
	        if (con != null) {
	            con.close();
	        }
	      } catch (SQLException ex) {
	          System.out.println(ex.getMessage());
	      }
	    }
	  }
	}

JSP Date

@signup_returns

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
    <title>Simple JSP Program</title>
</head>
<body>
    <h2>Welcome to My First JSP Program!</h2>
    <% 
        // Declaring a simple variable
        String userName = "User";
        // Getting the current date and time
        java.util.Date currentDate = new java.util.Date();
    %>
    <p>Hello, <%= userName %>!</p>
    <p>Current Date and Time: <%= currentDate %></p>
</body>
</html>

Scrollable Updatable ResultSet

@signup_returns

import java.sql.*;

public class ScrollableUpdatableResultSetExample {
    public static void main(String[] args) {
        // Database connection variables
        String url = "jdbc:oracle:thin:@localhost:1521:xe";  // Replace 'orcl' with your DB service name
        String username = "system"; // Oracle username
        String password = "1234";  // Oracle password
        
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;
        
        try {
            // Step 1: Load Oracle JDBC driver
            Class.forName("oracle.jdbc.OracleDriver");

            // Step 2: Establish a connection
            connection = DriverManager.getConnection(url, username, password);

            // Step 3: Create a statement with scrollable and updatable ResultSet
            statement = connection.createStatement(
                    ResultSet.TYPE_SCROLL_INSENSITIVE, // Scrollable
                    ResultSet.CONCUR_UPDATABLE          // Updatable
            );

            // Step 4: Execute the query to retrieve employees
            String query = "SELECT name, salary FROM employee";
            resultSet = statement.executeQuery(query);

            // Step 5: Scroll through the result set and update a record
            // Move to the first record
            if (resultSet.next()) {
                System.out.println("First Employee: " + resultSet.getString("name") + ", " 
                        + resultSet.getDouble("salary"));

                // Move to the second record
                if (resultSet.next()) {
                    System.out.println("Second Employee: " + resultSet.getString("name") + ", " 
                            + resultSet.getDouble("salary"));

                    // Update the salary of the second employee
                    resultSet.updateDouble("salary", resultSet.getDouble("salary") + 500); // Increase salary by 500
                    resultSet.updateRow(); // Apply the changes

                    System.out.println("Updated Salary for Second Employee: " + resultSet.getDouble("salary"));
                }
            }

            // Step 6: Commit changes (optional, if auto-commit is off)
            connection.commit();

        } catch (SQLException | ClassNotFoundException e) {
            // Handle SQL and ClassNotFound exceptions
            e.printStackTrace();
        } finally {
            // Step 7: Clean up resources
            try {
                if (resultSet != null) resultSet.close();
                if (statement != null) statement.close();
                if (connection != null) connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}

ENCRYPT, DECRYPT

@coding1

#include <stdio.h>
#include <string.h>

void encrypt(char *text, int key) {
    for (int i = 0; text[i] != '\0'; i++) {
        // Encrypt uppercase letters
        if (text[i] >= 'A' && text[i] <= 'Z') {
            text[i] = (text[i] - 'A' + key) % 26 + 'A';
        }
        // Encrypt lowercase letters
        else if (text[i] >= 'a' && text[i] <= 'z') {
            text[i] = (text[i] - 'a' + key) % 26 + 'a';
        }
    }
}

void decrypt(char *text, int key) {
    // Decrypt by shifting in the opposite direction
    for (int i = 0; text[i] != '\0'; i++) {
        // Decrypt uppercase letters
        if (text[i] >= 'A' && text[i] <= 'Z') {
            text[i] = (text[i] - 'A' - key + 26) % 26 + 'A';  // +26 to handle negative
        }
        // Decrypt lowercase letters
        else if (text[i] >= 'a' && text[i] <= 'z') {
            text[i] = (text[i] - 'a' - key + 26) % 26 + 'a';  // +26 to handle negative
        }
    }
}

int main() {
    char text[100];
    int key;

    printf("Enter the text to encrypt: ");
    fgets(text, sizeof(text), stdin);
    text[strcspn(text, "\n")] = 0; // Remove trailing newline

    printf("Enter the encryption key (shift): ");
    scanf("%d", &key);

    encrypt(text, key);
    printf("Encrypted text: %s\n", text);

    decrypt(text, key);
    printf("Decrypted text: %s\n", text);

    return 0;
}

DISTANCE VECTOR

@coding1

#include <stdio.h>

struct node {
    unsigned dist[20];
    unsigned from[20];
} rt[10];

int main() {
    int costmat[20][20];
    int nodes, i, j, k, count;

    printf("Enter the number of nodes: ");
    scanf("%d", &nodes);

    printf("Enter the cost matrix:\n");
    for (i = 0; i < nodes; i++) {
        for (j = 0; j < nodes; j++) {
            scanf("%d", &costmat[i][j]);
            rt[i].dist[j] = costmat[i][j]; // Initialize distance
            rt[i].from[j] = (costmat[i][j] != 0 && costmat[i][j] != 1000) ? j : -1; // Set 'from' based on cost
        }
    }

    // Set diagonal to 0
    for (i = 0; i < nodes; i++) {
        rt[i].dist[i] = 0;
        rt[i].from[i] = i;
    }

    // Floyd-Warshall Algorithm
    do {
        count = 0;
        for (i = 0; i < nodes; i++) {
            for (j = 0; j < nodes; j++) {
                for (k = 0; k < nodes; k++) {
                    if (rt[i].dist[j] > rt[i].dist[k] + rt[k].dist[j]) {
                        rt[i].dist[j] = rt[i].dist[k] + rt[k].dist[j];
                        rt[i].from[j] = k;
                        count++;
                    }
                }
            }
        }
    } while (count != 0);

    // Output the final routing table
    printf("\nUpdated routing table\n");
    for (i = 0; i < nodes; i++) {
        for (j = 0; j < nodes; j++) {
            if (rt[i].from[j] != -1) {
                printf("%d ", rt[i].dist[j]);
            } else {
                printf("inf ");  // Use "inf" to indicate no path
            }
        }
        printf("\n");
    }

    return 0;
}

SUBNET

@coding1

#include<stdio.h>
int p,q,u,v,n;
int min=99;
int minCost=0;
int t[50][2],i,j;
int parent[50],edge[50][50];

int main(){
    clrsrc();
    printf("\nEnter the number of nodes");
    scanf("%d",&n);
    for(i=0;i<n;i++){
        printf("%d",i);
        parent[i]=-1;
    }
    printf("\n");
    for(i=0;i<n;i++){
        printf("%c",65+i);
        for(j=0;j<n;j++){
            scanf("%d",&edge[i][j]);
        }
        for(i=0;i<n;i++){
            for(j=0;j<n;j++){
                if(edge[1][j]!=99){
                    if(min<edge[i][j]){
                        min=edge[i][j];
                        u=i;
                        v=j;
                    }
                    p=find(u);
                    q=find(v);
                    
                    if(p!=q){
                        t[i][0]=u;
                        t[i][1]=v;
                        minCost =minCost+edge[u][v];
                        sunion(p,q);
                    }
                    else{
                        t[i][0]=-1;
                        t[i][1]=-1;
                    }
                }
            }
        }
        min = 99;
    }
    printf("Minimum cost is %d\n Minimum spanning tree is\n",minCost);
    for(i=0;i<n;i++){
        if(t[i][0]!=-1 && t[i][1]!=1){
            printf("%c %c %d",65+t[i][0],65+t[i][1],edge[t[i][0]] [t[i][1]]);
            printf("\n");
        }
        getch();
    }
    sunion(int I,int m){
        parent[] = m;
    }
    find(int I){
        if(parent[1]>0){
            I=parent[I];
        }
        return I;
    }
}

DIJKSTRA

@coding1

#include<stdio.h>
#include<stdbool.h>
#include<limits.h>
#define V 9

int minDistance(int dist[] ,bool sptset[]){
    int min = INT_MAX;  
    int min_index;
    for(int v=0;v<V;v++){
        if(sptset[v] == false && dist[v]<=min){
            min = dist[v];
            min_index = v;
        }
    }
    return min_index;
}

void printSolution(int dist[]){
    printf("Vertex\t\tDistance from source\n");
    for(int i=0;i<V;i++){
        printf("%d\t\t\t\t %d\n",i,dist[i]);
    }
}

void dijkstra(int graph[V][V],int src){
    int dist[V];
    bool sptset[V];
    for(int i=0;i<V;i++){
        dist[i] = INT_MAX;
        sptset[1]=false;
    }
    dist[src]=0;
    for(int count=0;count<V-1;count++){
        int u = minDistance(dist,sptset);
        sptset[u]=true;
        for(int v=0;v<V;v++){
            if(!sptset[v] && graph[u][v] && dist[u]!=INT_MAX && dist[u]+graph[u][v] < dist[v])
                dist[v] = dist[u]+graph[u][v];
        }
    }
    printSolution(dist);
}

int main(){
    int graph[V][V] = {{0,4,0,0,0,0,0,8,0},
               {4,0,8,0,0,0,0,11,0},
               {0,8,0,7,0,4,0,0,2},
               {0,0,7,0,9,14,0,0,0},
               {0,0,0,9,0,10,0,0,0},
               {0,0,4,14,10,0,2,0,0},
               {0,0,0,0,0,2,0,1,6},
               {8,11,0,0,0,0,1,0,7},
               {0,0,2,0,0,0,6,7,0}};
    dijkstra(graph,0);
    return 0;
}

SLIDING WINDOW

@coding1

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdbool.h>

#define MAX_SEQ 4 // Maximum sequence number (0 to 7)
#define WINDOW_SIZE 4  // Size of the sliding window

// Packet structure
typedef struct {
    int seq_num;  // Sequence number
    bool ack;     // Acknowledgment flag
} Packet;

// Function prototypes
void sender();
void receiver();
void send_packet(Packet packet);
bool receive_packet(Packet packet);
bool simulate_packet_loss();

int main() {
    // Start sender and receiver (in a real implementation, these would run in separate threads or processes)
    sender();
    receiver();
    return 0;
}

void sender() {
    int next_seq_num = 0; // Next sequence number to send
    int acked = 0; // Last acknowledged packet
    int window_start = 0; // Start of the sliding window

    while (window_start <= MAX_SEQ) {
        // Send packets within the window
        while (next_seq_num < window_start + WINDOW_SIZE && next_seq_num <= MAX_SEQ) {
            Packet packet = {next_seq_num, false};
            send_packet(packet);
            next_seq_num++;
            sleep(1); // Simulate time taken to send a packet
        }

        // Simulate receiving an acknowledgment (in real systems this would be from the receiver)
        for (int i = acked; i < next_seq_num; i++) {
            if (receive_packet((Packet){i, true})) {
                acked++;
            }
        }

        // Slide the window
        window_start = acked;
        next_seq_num = window_start; // Move next_seq_num to the next unacknowledged packet
    }

    printf("Sender finished transmitting all packets.\n");
}

void receiver() {
    for (int i = 0; i <= MAX_SEQ; i++) {
        sleep(1); // Simulate processing time for receiving a packet
        if (simulate_packet_loss()) {
            printf("Receiver: Lost packet with seq_num %d\n", i);
            continue; // Simulate loss
        }
        printf("Receiver: Received packet with seq_num %d\n", i);
    }
}

void send_packet(Packet packet) {
    printf("Sender: Sending packet with seq_num %d\n", packet.seq_num);
}

bool receive_packet(Packet packet) {
    // Simulate acknowledgment logic
    if (packet.ack) {
        printf("Receiver: Acknowledgment for packet with seq_num %d\n", packet.seq_num);
        return true;
    }
    return false;
}

bool simulate_packet_loss() {
    // Randomly simulate packet loss (30% chance)
    return (rand() % 10) < 3;

Basic Web Page of University

@signup_returns

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>University Demo</title>
    <style>
        /* Basic CSS styles for layout and appearance */
        body {
            font-family: Arial, sans-serif;
            margin: 0;
            padding: 0;
            background-color: #f4f4f9;
        }
        header {
            background-color: #4CAF50;
            color: white;
            padding: 20px;
            text-align: center;
        }
        nav {
            background-color: #333;
            overflow: hidden;
        }
        nav a {
            float: left;
            display: block;
            color: white;
            padding: 14px 20px;
            text-align: center;
            text-decoration: none;
        }
        nav a:hover {
            background-color: #ddd;
            color: black;
        }
        section {
            padding: 20px;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 20px;
        }
        footer {
            background-color: #333;
            color: white;
            text-align: center;
            padding: 10px 0;
            position: fixed;
            width: 100%;
            bottom: 0;
        }
    </style>
</head>
<body>
    <header>
        <h1>Welcome to Our University</h1>
        <p>Empowering Future Leaders</p>
    </header>
    
    <nav>
        <a href="#about">About</a>
        <a href="#courses">Courses</a>
        <a href="#contact">Contact</a>
    </nav>

    <section id="about">
        <div class="container">
            <h2>About Us</h2>
            <p>Our University is dedicated to providing world-class education to students from all walks of life. We offer a wide range of academic programs designed to foster growth and leadership in our students.</p>
        </div>
    </section>

    <section id="courses">
        <div class="container">
            <h2>Our Courses</h2>
            <ul>
                <li>Bachelor of Science in Computer Science</li>
                <li>Master of Business Administration</li>
                <li>Bachelor of Arts in History</li>
                <li>PhD in Physics</li>
                <li>Master of Engineering in Civil</li>
            </ul>
        </div>
    </section>

    <section id="contact">
        <div class="container">
            <h2>Contact Us</h2>
            <p>Email: contact@university.com</p>
            <p>Phone: +123 456 7890</p>
            <p>Address: 123 University St, City, Country</p>
        </div>
    </section>

    <footer>
        <p>&copy; 2024 University Demo. All rights reserved.</p>
    </footer>
</body>
</html>

CRC CODE

@coding1

include <stdio.h>
#include <string.h>

#define MAX_LEN 28

char t[MAX_LEN], cs[MAX_LEN], g[MAX_LEN];
int a, e, c, b;

void xor() {
    for (c = 1; c < strlen(g); c++)
        cs[c] = ((cs[c] == g[c]) ? '0' : '1');
}

void crc() {
    for (e = 0; e < strlen(g); e++)
        cs[e] = t[e];
    
    do {
        if (cs[0] == '1') {
            xor();
        }
        
        for (c = 0; c < strlen(g) - 1; c++)
            cs[c] = cs[c + 1];
        
        cs[c] = t[e++];
    } while (e <= a + strlen(g) - 1);
}

int main() {
    int flag = 0;
    do {
        printf("\n1. CRC-12\n2. CRC-16\n3. CRC-CCITT\n4. Exit\n\nEnter your option: ");
        scanf("%d", &b);

        switch (b) {
            case 1: 
                strcpy(g, "1100000001111");
                break;
            case 2: 
                strcpy(g, "11000000000000101");
                break;
            case 3: 
                strcpy(g, "10001000000100001");
                break;
            case 4: 
                return 0;
            default:
                printf("Invalid option. Please try again.\n");
                continue;
        }

        printf("\nEnter data: ");
        scanf("%s", t);
        printf("\n-----------------------\n");
        printf("Generating polynomial: %s\n", g);
        a = strlen(t);

        // Append zeros to the data
        for (e = a; e < a + strlen(g) - 1; e++)
            t[e] = '0';
        t[e] = '\0';  // Null terminate the string

        printf("--------------------------\n");
        printf("Modified data is: %s\n", t);
        printf("-----------------------\n");
        crc();
        printf("Checksum is: %s\n", cs);
        
        // Prepare the final codeword
        for (e = a; e < a + strlen(g) - 1; e++)
            t[e] = cs[e - a];
        printf("-----------------------\n");
        printf("Final codeword is: %s\n", t);
        printf("------------------------\n");

        // Error detection option
        printf("Test error detection (0: yes, 1: no)?: ");
        scanf("%d", &e);
        if (e == 0) {
            do {
                printf("\n\tEnter the position where error is to be inserted: ");
                scanf("%d", &e);
            } while (e <= 0 || e > a + strlen(g) - 1);
            
            t[e - 1] = (t[e - 1] == '0') ? '1' : '0'; // Toggle the bit
            printf("-----------------------\n");
            printf("\nErroneous data: %s\n", t);
        }

        crc();
        for (e = 0; (e < strlen(g) - 1) && (cs[e] != '1'); e++);
        if (e < strlen(g) - 1)
            printf("Error detected\n\n");
        else
            printf("No error detected\n\n");
        
        printf("-----------------------\n");
    } while (flag != 1);

    return 0;
}

BIT STUFFING

@coding1

#include<stdio.h>
#include<string.h>

void bitStuffing(char *str) {
    int i, count = 0;
    char stuffedStr[100] = ""; // initialize an empty string to store the stuffed bits

    for (i = 0; i < strlen(str); i++) {
        if (str[i] == '1') {
            count++;
            if (count == 5) {
                strcat(stuffedStr, "0"); // stuff a '0' bit
                count = 0;
            }
        } else {
            count = 0;
        }
        char temp[2];
        sprintf(temp, "%c", str[i]);
        strcat(stuffedStr, temp);
    }

    printf("Original string: %s\n", str);
    printf("Bit-stuffed string: %s\n", stuffedStr);
}

int main() {
    char str[100];
    printf("Enter a binary string: ");
    scanf("%s", str);

    bitStuffing(str);

    return 0;
}

CHARACTER STUFFING

@coding1

include <stdio.h>
#include <string.h>

#define FRAME_START 0x7E // Start of Frame
#define FRAME_END 0x7E   // End of Frame
#define STUFFING_CHAR 0x7D // Escape character
#define ESCAPED_CHAR 0x20  // Value to append after STUFFING_CHAR

void stuffCharacters(char *input, char *output) {
    int i, j = 0;
    int length = strlen(input);

    // Adding the frame start character
    output[j++] = FRAME_START;

    for (i = 0; i < length; i++) {
        if (input[i] == FRAME_START || input[i] == FRAME_END || input[i] == STUFFING_CHAR) {
            output[j++] = STUFFING_CHAR; // Stuffing character
            output[j++] = input[i] ^ ESCAPED_CHAR; // Escape the character
        } else {
            output[j++] = input[i]; // Normal character
        }
    }

    // Adding the frame end charactera
    output[j++] = FRAME_END;
    output[j] = '\0'; // Null-terminate the output string
}

void unstuffCharacters(char *input, char *output) {
    int i, j = 0;
    int length = strlen(input);

    // Skip frame start
    i = 1; 

    while (i < length - 1) { // Skip frame end
        if (input[i] == STUFFING_CHAR) {
            // Unstuffing character
            output[j++] = input[i + 1] ^ ESCAPED_CHAR;
            i += 2; // Move past the stuffed character
        } else {
            output[j++] = input[i++];
        }
    }

    output[j] = '\0'; // Null-terminate the output string
}

int main() {
    char input[256]; // Buffer for input message
    char stuffed[512]; // Buffer for stuffed message (larger to accommodate potential expansion)
    char unstuffed[256]; // Buffer for unstuffed message

    printf("Enter your message: ");
    fgets(input, sizeof(input), stdin); // Read input from the keyboard

    // Remove newline character if present
    input[strcspn(input, "\n")] = 0;

    printf("Original Message: %s\n", input);

    // Perform character stuffing
    stuffCharacters(input, stuffed);
    printf("Stuffed Message: ");
    for (int i = 0; stuffed[i] != '\0'; i++) {
        printf("%02X ", (unsigned char)stuffed[i]);
    }
    printf("\n");

    // Perform character unstuffing
    unstuffCharacters(stuffed, unstuffed);
    printf("Unstuffed Message: %s\n", unstuffed);

    return 0;
}

CHARACTER COUNT

@coding1

#include<stdio.h>
#include<string.h>

int main(){
    int n,i,j,c=0,count=0;
    char str[100]; 
    printf("Enter the string: ");
    scanf("%s", str); 

    printf("Enter the number of frames:");
    scanf("%d",&n);
    int frames[n];

    printf("Enter the frame size of the frames:\n");
    for(int i=0;i<n;i++){
        printf("Frame %d:",i);
        scanf("%d",&frames[i]);
    }

    printf("\nThe number of frames:%d\n",n);
    c = 0;
    for(int i=0;i<n;i++){
        printf("The content of the frame %d:",i);
        j=0;
        count = 0; 
        while(c < strlen(str) && j < frames[i]){
            printf("%c",str[c]);
            if(str[c]!='\0'){
                count++;
            }
            c=c+1;
            j=j+1;
        }
        printf("\nSize of frame %d: %d\n\n",i,count);
    }
    return 0;
}

Clears keyboard Buffer

@Bantling21

/*
* Clears the keyboard if an invalid input was put in
*/
void clear_keyboard_buffer(void)
{
	char c = 'a';
	while (c != '\n')
	{
		scanf("%c", &c);
	}
	return;
}

Gets a user integer greater than a specified value

@Bantling21

/*
* Gets a user integer greater than a specified value
* @param int val
*		- The value that the user input is to be greater than 
*/
int get_user_greater_int(int val)
{
	int input, noc;
	printf("Enter an Interger Greater than %d: ", val);
	noc = scanf("%d", &input);
	clear_keyboard_buffer();

	while (noc != 1 || !(input >= 0))
	{
		printf("Invalid input\nEnter an Interger Greater than %d", val);
		noc = scanf("%d", &input);
		clear_keyboard_buffer();
	}

	return input;
}

13. Demonstrate Creation of Servlet program using Http Servlet class.

@webtechnologies

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.annotation.WebServlet;

@WebServlet("/hello")
public class HelloWorldServlet extends HttpServlet {
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html");
        response.getWriter().println("<h1>Hello, World!</h1>");
    }
}

Servlet LifeCycle

@webtechnologies

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.ServletConfig;
import javax.servlet.annotation.WebServlet;

@WebServlet("/lifecycle")
public class LifecycleServlet implements javax.servlet.Servlet {
    public void init(ServletConfig config) throws ServletException {
        System.out.println("Servlet Initialized");
    }

    public void service(ServletRequest req, ServletResponse res) throws ServletException, IOException {
        System.out.println("Servlet is servicing the request");
    }

    public void destroy() {
        System.out.println("Servlet Destroyed");
    }

    public ServletConfig getServletConfig() {
        return null;
    }

    public String getServletInfo() {
        return null;
    }
}
web.xml

<web-app xmlns="http://java.sun.com/xml/ns/javaee" version="3.0">
    <servlet>
        <servlet-name>LifecycleServlet</servlet-name>
        <servlet-class>LifecycleServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>LifecycleServlet</servlet-name>
        <url-pattern>/lifecycle</url-pattern>
    </servlet-mapping>
</web-app>

Meta Data

@webtechnologies

import java.sql.*;

public class DatabaseMetadataExample {
    public static void main(String[] args) {
        try {
            Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/your_database", "username", "password");
            DatabaseMetaData metaData = connection.getMetaData();
            
            System.out.println("Database Product Name: " + metaData.getDatabaseProductName());
            System.out.println("Database Product Version: " + metaData.getDatabaseProductVersion());
            System.out.println("Driver Name: " + metaData.getDriverName());
            System.out.println("Driver Version: " + metaData.getDriverVersion());
            
            connection.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

DOM parser

@webtechnologies

import org.w3c.dom.*;
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.validation.*;
import java.io.File;

public class DOMXMLValidator {
    public static void main(String[] args) {
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            Document doc = builder.parse(new File("example.xml"));
            
            SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
            Schema schema = schemaFactory.newSchema(new File("schema.xsd"));
            Validator validator = schema.newValidator();
            validator.validate(new DOMSource(doc));
            
            System.out.println("XML is valid.");
        } catch (Exception e) {
            System.out.println("XML is not valid: " + e.getMessage());
        }
    }
}

5. Write a JavaScript program to demonstrate the working of callbacks, promises, and async/await.

@webtechnologies

function greetUserPromise(name) {
    return new Promise((resolve) => {
        console.log(`Hi ${name}`);  
        resolve();
    });
}

function greetUserCallback(name, callback) {
    callback();
    console.log(`${name}`); 
}

function greetforCall() {
    console.log("Hello");
}

async function greetUserAsync() {
    try {
        await greetUserPromise("Arun");
        console.log("Hello Arun");
    } catch (error) {
        console.error("An error occurred:", error);
    }
}

greetUserAsync();

greetUserCallback("Arun", greetforCall);

User Wishes To Continue && Clear Keyboard Buffer

@Bantling21

int user_wishes_to_continue(void)
{
	char c;
	do
	{
		printf("Do you wish to continue? (Y/N)");
		scanf("%c", &c);
		clear_keyboard_buffer();
	} while (c != 'y' && c != 'Y' && c != 'n' && c != 'N');

	return (c == 'Y');
}

void clear_keyboard_buffer(void)
{
	char c = 'a';
	while (c != '\n')
	{
		scanf_s("%c", &c);
	}
	return;
}

4. Demonstrate Responsive Web Design using Media Queries to create a webpage.

@webtechnologies

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Responsive Web Design</title>
    <style>
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: Arial, sans-serif;
            background-color: #f4f4f4;
        }


        header {
            background-color: #3498db;
            color: white;
            padding: 20px;
            text-align: center;
        }


        .container {
            padding: 20px;
        }


        .content {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 20px;
        }

        .content div {
            background-color: #2980b9;
            color: white;
            text-align: center;
            padding: 20px;
            border-radius: 8px;
        }

        @media (max-width: 768px) {
            .content {
                grid-template-columns: repeat(2, 1fr);

            }
        }


        @media (max-width: 480px) {
            .content {
                grid-template-columns: 1fr;

            }

            header {
                padding: 15px;

            }

            .content div {
                font-size: 14px;

            }
        }
    </style>
</head>

<body>
    <header>
        <h1>Responsive Web Design</h1>
    </header>

    <div class="container">
        <div class="content">
            <div>Item 1</div>
            <div>Item 2</div>
            <div>Item 3</div>
        </div>
    </div>
</body>

</html>

Database connection of servlets

Database Connection JSP

Login JSP

Connect JSP

Date JSP

Request JSP

Scrollable And Updatable Result Set

Multiple Connection

jsp request 1 page

form Parameters

book (dtd)

16. Write a java based application to demonstrate the Scrollable Result sets.

15. Write a java program to demonstrate the usage of JDBC in performing various DML statements using prepared statements.

14. Write a java program to establish a connection to a database and execute simple SQL queries.

Make sure local branch matches remote branch

console_getProjectKey_each

cloud_console_getAllProjects

Fat Arrows in js

Login JSP

Connect JSP

Date JSP

Request JSP

Jdbc Transaction

Result Set Meta Data

JSP request paramaters

Jdbc Multiple Connection

Hit Counter

JSP Database

Jdbc Connection

JSP Date

Scrollable Updatable ResultSet

ENCRYPT, DECRYPT

DISTANCE VECTOR

SUBNET

DIJKSTRA

SLIDING WINDOW

Basic Web Page of University

CRC CODE

BIT STUFFING

CHARACTER STUFFING

CHARACTER COUNT

Clears keyboard Buffer

Gets a user integer greater than a specified value

13. Demonstrate Creation of Servlet program using Http Servlet class.

Servlet LifeCycle

Meta Data

DOM parser

5. Write a JavaScript program to demonstrate the working of callbacks, promises, and async/await.

User Wishes To Continue && Clear Keyboard Buffer

4. Demonstrate Responsive Web Design using Media Queries to create a webpage.

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