Create a JDialog to get input for address in Java

import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
/*from ww  w . j  ava 2 s  .  com*/
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;

class AddressDialog extends JDialog {
  JLabel label1 = new JLabel("Address");

  JLabel label2 = new JLabel("City");

  JLabel label3 = new JLabel("State");

  JLabel label4 = new JLabel("Zip Code");

  JTextField addressField = new JTextField();

  JTextField cityField = new JTextField();

  JTextField stateField = new JTextField();

  JTextField zipCodeField = new JTextField();

  String[] address = new String[4];

  public AddressDialog(Frame owner, boolean modal) {
    super(owner, modal);
    init();
  }

  private void init() {
    this.setTitle("Address Dialog");
    this.setLayout(new GridLayout(4, 2));
    this.add(label1);
    this.add(addressField);
    this.add(label2);
    this.add(cityField);
    this.add(label3);
    this.add(stateField);
    this.add(label4);
    this.add(zipCodeField);
  }

  public String[] getAddress() {
    address[0] = addressField.getText();

    address[1] = cityField.getText();
    address[2] = stateField.getText();
    address[3] = zipCodeField.getText();
    return address;
  }
}

public class Main extends JFrame {
  AddressDialog dialog = new AddressDialog(this, false);

  public Main() {
    super();

    this.getContentPane().setLayout(new FlowLayout());
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    final AddressDialog dialog = new AddressDialog(this, false);
    JButton button = new JButton("Show Dialog");
    button.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent ae) {
        dialog.setSize(250, 120);
        dialog.setVisible(true);
      }
    });
    this.getContentPane().add(button);
  }

  public static void main(String[] args) {
    Main frame = new Main();
    frame.pack();
    frame.setVisible(true);
  }
}