Sorry i forget to put my code i got two class. this is the first class print("import javax.swing.*; import java.awt.event.*; import java.util.*;

public class AddressList{ JComboBox combo; JTextField txtBox; private String PersonViewing; private String TelephoneNumber; private String Address; private JFrame Addressframe; Address Alist;

/**
 * Return the name of person that are viewing the property
 */
public String getName()
{
    return PersonViewing;
}    
  /**
 * Return the address of person that are viewing the property
 */
public String getAddress()
{
    return PersonViewing;
}    

/**
 * Return the telephone number of person that are viewing the property
 */
public String getTelephoneNumberOfPerson()
{
    return TelephoneNumber;
}    



public AddressList(){
    JFrame frame = new JFrame("Add-Remove item to  list");
    String items[] = {"", "", "", "", ""};
    combo = new JComboBox(items);
    JButton button1 = new JButton("Add new item");
    txtBox = new JTextField(35);

    button1.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){

                Address Alist = new  Address();
            }
        }); 
    JButton button2 = new JButton("Remove");
    button2.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                if (combo.getItemCount() > 0)
                    combo.removeItemAt(0);
                else
                    JOptionPane.showMessageDialog(null,"the viewing list is empty ");
            }
        });
    JPanel panel = new JPanel();
    JPanel panel1 = new JPanel();
    panel.add(txtBox);
    panel.add(combo);
    panel.add(button1);
    panel.add(button2);
    frame.add(panel);
    //  frame.add(panel1);
    frame.setSize(320, 350);
    frame.setVisible(true);
    frame.setResizable(false);
    boolean resizable = frame.isResizable();
}

}"); abd this is the second class `print("import javax.swing.*; import java.awt.event.*; import java.util.*; import java.awt.*;

public class Address { public Address() { JFrame frame3 = new JFrame("Adding the new propert"); JPanel panel = new JPanel(new GridLayout(4,2,20,30)); panel.add(new JLabel("Name" )); panel.add(new JTextField(5)); panel.add(new JLabel("Telphone")); panel.add(new JTextField(3)); panel.add(new JLabel("Address")); panel.add(new JTextField(3)); panel.add(new JButton("Confirm")); panel.add(new JButton("Cancel"));

frame3.add(panel); frame3.setSize(350,350); frame3.setVisible(true); } }e");`

thanks

Sorry for the previous message

import javax.swing.*;
import java.awt.event.*;
import java.util.*;

public class AddressList{
    JComboBox combo;
    JTextField txtBox;
    private String PersonViewing;
    private String TelephoneNumber;
    private String Address;
    private JFrame Addressframe;
    Address Alist;

    /**
     * Return the name of person that are viewing the property
     */
    public String getName()
    {
        return PersonViewing;
    }    
      /**
     * Return the address of person that are viewing the property
     */
    public String getAddress()
    {
        return PersonViewing;
    }    

    /**
     * Return the telephone number of person that are viewing the property
     */
    public String getTelephoneNumberOfPerson()
    {
        return TelephoneNumber;
    }    



    public AddressList(){
        JFrame frame = new JFrame("Add-Remove item to  list");
        String items[] = {"", "", "", "", ""};
        combo = new JComboBox(items);
        JButton button1 = new JButton("Add new item");
        txtBox = new JTextField(35);

        button1.addActionListener(new ActionListener(){
                public void actionPerformed(ActionEvent e){

                    Address Alist = new  Address();
                }
            }); 
        JButton button2 = new JButton("Remove");
        button2.addActionListener(new ActionListener(){
                public void actionPerformed(ActionEvent e){
                    if (combo.getItemCount() > 0)
                        combo.removeItemAt(0);
                    else
                        JOptionPane.showMessageDialog(null,"the viewing list is empty ");
                }
            });
        JPanel panel = new JPanel();
        JPanel panel1 = new JPanel();
        panel.add(txtBox);
        panel.add(combo);
        panel.add(button1);
        panel.add(button2);
        frame.add(panel);
        //  frame.add(panel1);
        frame.setSize(320, 350);
        frame.setVisible(true);
        frame.setResizable(false);
        boolean resizable = frame.isResizable();
    }
}

import javax.swing.*;
import java.awt.event.*;
import java.util.*;
import java.awt.*;


public class  Address
{
public  Address()
{
  JFrame frame3 = new JFrame("Adding the new propert");
  JPanel panel = new JPanel(new GridLayout(4,2,20,30));
  panel.add(new JLabel("Name"  ));
  panel.add(new JTextField(5));
  panel.add(new JLabel("Telphone"));
  panel.add(new JTextField(3));
  panel.add(new JLabel("Address"));
  panel.add(new JTextField(3));
  panel.add(new JButton("Confirm"));
  panel.add(new JButton("Cancel"));


  frame3.add(panel);
  frame3.setSize(350,350);
  frame3.setVisible(true);
  }
}

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

public class AddRemoveItemFromCombo{
  JComboBox combo;
  public static void main(String[] args){
  AddRemoveItemFromCombo ar = new AddRemoveItemFromCombo();
  }

  public AddRemoveItemFromCombo(){
  final JFrame frame = new JFrame("Add-Remove Item of a Combo Box");
  combo = new JComboBox();
  JButton button1 = new JButton("Add");
  button1.addActionListener(new ActionListener(){
  public void actionPerformed(ActionEvent e){
  final JFrame frame3 = new JFrame("Adding the new propert");
  JPanel panel = new JPanel(new GridLayout(4,2,20,30));
  JButton b1=new JButton("Confirm");
  JButton b2=new JButton("Cancel");
  final JTextField text1=new JTextField(3);
  final JTextField text2=new JTextField(3);
  final JTextField text3=new JTextField(3);
  panel.add(new JLabel("Name"));
  panel.add(text1);
  panel.add(new JLabel("Telphone"));
  panel.add(text2);
  panel.add(new JLabel("Address"));
  panel.add(text3);
  panel.add(b1);
  panel.add(b2);
  frame3.add(panel);
  frame3.setSize(350,350);
  frame3.setVisible(true);

  b1.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){
        frame.setFocusable(true);
        StringBuffer buffer=new StringBuffer();
         buffer.append(text1.getText()).append(", ").append(text2.getText()).append(", ").append(text3.getText());
         String text=buffer.toString();
         System.out.println(text);
         if (!text.equals("")){
            int a = 0;
            for(int i = 0; i < combo.getItemCount(); i++){
               if(combo.getItemAt(i).equals(text)){
               a = 1;
               break;
               }
            }
            if (a == 1)
               JOptionPane.showMessageDialog(null,"Combo has already this item.");
            else
               combo.addItem(text);
         }
         else{
               JOptionPane.showMessageDialog(null,"Please enter text in Text Box");
         }
         frame3.setVisible(false);
         }
       });
     }
  });
  JButton button2 = new JButton("Remove");
  button2.addActionListener(new ActionListener(){
  public void actionPerformed(ActionEvent e){
  if (combo.getItemCount() > 0)
  combo.removeItemAt(0);
  else
  JOptionPane.showMessageDialog(null,"Item not available");
  }
  });
  JPanel panel = new JPanel();
  JPanel panel1 = new JPanel();
  panel.add(combo);
  panel.add(button1);
  panel.add(button2);
  frame.add(panel);
  frame.setSize(400, 400);
  frame.setVisible(true);
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }
}

thanks you i would like ask another question i would like to make a non GUI class of list of address and put on the combox box how i could to do that ?