content: package com.ramaguru.amrita.cys.jpl.gui.swing.apps;
  
  import javax.swing.*;
  import javax.swing.table.DefaultTableModel;
  import java.awt.*;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  
  /**
   * Address book application for 21CYS
   * @author Ramaguru Radhakrishnan
   * @version 1.0
   */
  public class U21CYSAddressBook extends JFrame {
  
      private JTable contactTable;
      private DefaultTableModel tableModel;
  
      private JTextField nameField;
      private JTextField phoneField;
      private JTextField emailField;
  
      /**
       * Constructs the U21CYSAddressBook frame.
       * Initializes the GUI components and sets up the layout.
       */
      public U21CYSAddressBook() {
          setTitle("21CYS Address Book");
          setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  
          // Create the table with default table model
          tableModel = new DefaultTableModel(new Object[]{"Name", "Phone Number", "Email"}, 0);
          contactTable = new JTable(tableModel);
  
          // Create the scroll pane and add the table to it
          JScrollPane scrollPane = new JScrollPane(contactTable);
  
  
          // Create the main panel and set layout
          JPanel mainPanel = new JPanel();
          mainPanel.setLayout(new BorderLayout());
  
          // Create the form panel and add labels and text fields
          JPanel formPanel = new JPanel();
  
  
          // Create the button panel and add buttons
          JPanel buttonPanel = new JPanel();
  
  
          // Add scroll pane, form panel, and button panel to the main panel
          mainPanel.add(scrollPane, BorderLayout.CENTER);
          mainPanel.add(formPanel, BorderLayout.NORTH);
          mainPanel.add(buttonPanel, BorderLayout.SOUTH);
  
          // Add the main panel to the content pane
          Container container = getContentPane();
          container.add(mainPanel);
  
          pack();
          setLocationRelativeTo(null); // Center the frame on the screen
      }
  
      /**
       * Validates a phone number.
       *
       * @param phone the phone number to validate
       * @return true if the phone number is valid, false otherwise
       */
      private boolean isValidPhoneNumber(String phone) {
          // Perform validation logic for phone number (e.g., length, format, etc.)
          return true;
      }
  
      /**
       * Validates an email address.
       *
       * @param email the email address to validate
       * @return true if the email address is valid, false otherwise
       */
      private boolean isValidEmail(String email) {
          // Perform validation logic for email (e.g., format, etc.)
          return true;
      }
  
      /**
       * Clears the form fields.
       */
      private void clearFormFields() {
  
      }
  
      /**
       * ActionListener for the Add button.
       * Adds a new contact to the address book.
       */
      private class AddButtonListener implements ActionListener {
          @Override
          public void actionPerformed(ActionEvent e) {
  
          }
      }
  
      /**
       * ActionListener for the Edit button.
       * Edits an existing contact in the address book.
       */
      private class EditButtonListener implements ActionListener {
          @Override
          public void actionPerformed(ActionEvent e) {
  
          }
      }
  
      /**
       * ActionListener for the Delete button.
       * Deletes a contact from the address book.
       */
      private class DeleteButtonListener implements ActionListener {
          @Override
          public void actionPerformed(ActionEvent e) {
  
          }
      }
  
      /**
       * Entry point of the application.
       * Creates and displays the U21CYSAddressBook frame.
       *
       * @param args the command-line arguments
       */
      public static void main(String[] args) {
          SwingUtilities.invokeLater(new Runnable() {
              public void run() {
                  new U21CYSAddressBook().setVisible(true);
              }
          });
      }
  }
  