java

/*
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 * and open the template in the editor.
 */
package dbconn;
import java.sql.*;
/**
 *
 * @author MYPC
 */
public class DBConn {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        insert();
        select();
        numberPalindrome();
        reverseArray();
        stringPalindrome();


    }
    public static void insert(){
         String dbURL = "jdbc:mysql://localhost:3306/sampledb";
        String username = "root";
        String password = "";
        String query = "INSERT INTO Users(username, password, fullname, email) Values(?,?,?,?)";

        try {
            Connection conn = DriverManager.getConnection(dbURL, username, password);
            if (conn != null) {
                System.out.println("Connected");
            }
              PreparedStatement statement = conn.prepareStatement(query);
              statement.setString(1, "bill2222");
              statement.setString(2, "secretpass22");
              statement.setString(3, "bill gates22");
              statement.setString(4, "bill@gmail.com22");

              int rowsInserted = statement.executeUpdate();
              if (rowsInserted > 0) {
                  System.out.println("Successfully entered");
              }
             conn.close();
        }catch(Exception ex) {
            System.out.println("Error: " + ex);
        }
    }

    public static void select() {
        String dbURL = "jdbc:mysql://localhost:3306/sampledb";
        String username = "root";
        String password = "";
        String query = "SELECT * from Users";

        try {
            Connection conn = DriverManager.getConnection(dbURL, username, password);
            if (conn != null) {
                System.out.println("Connected");
            }
              Statement statement = conn.createStatement();
              ResultSet result = statement.executeQuery(query);

              int count = 0;

              while (result.next()) {
                  String name = result.getString(2);
                  String pass = result.getString(3);
                  String fullname = result.getString("fullname");
                  String email = result.getString(5);
                  String output = "User #%d: %s - %s - %s - %s";

                  System.out.println(String.format(output, ++count, name, pass, fullname, email));

              }

             conn.close();
        }catch(Exception ex) {
            System.out.println("Error: " + ex);
        }
    }

    public static void numberPalindrome() {
        int number = 12345;
        int remainder = 0, sum = 0;
        while(number > 0) {
            remainder = number %10;

            sum = (sum * 10) + remainder;
            number /= 10;
        }
        System.out.println(sum);
    }

    public static void reverseArray() {
        int arr[] = {1, 2,3,4,5};

         for(int i = 0; i < arr.length/2; i++) {
             int temp = arr[i];
             arr[i] = arr[arr.length-1 -i];
             arr[arr.length-1 -i] = temp;
         }
         for(int n : arr) {
             System.out.print(n);
         }
    }

    public static void stringPalindrome() {
        String word = "123";
        String rev = "";
//      for(int i = word.length()-1; i >= 0 ; i--) {
//            rev += word.charAt(i);
//        }
    for(int i = 0; i < word.length();i++) {
            rev += word.charAt(word.length()-i -1);
        }
        System.out.println("\n"+rev);
    }
}